GRAY HERBARIUM OF HARVARD UNIVERSITY CONTRIBUTIONS Nos. 198-202 1969-1971 _ Wisgsour! BoTANICam Gareden LigsaRge ‘ ANCHESTER, INDIANA CONTRIBUTIONS FROM THE GRAY HERBARIUM OF HARVARD UNIVERSITY Edited by Reed C. Rollins and Robert C. Foster No. cxcvil ~ 202 A REMARKABLE NEW CRUCIFER FROM MEXICO By Reep C. ROLLINS PETAL COLOR POLYMORPHISMS IN LEAVENWORTHIA (CRUCIFERAE) By Davip G. LLoyp THE GENUS KALLSTROEMIA (ZYGOPHYLLACEAE ) By DuncAN M. PorTER PUBLISHED BY THE GRAY HERBARIUM OF HARVARD UNIVERSITY CAMBRIDGE, MASS. U. S. A. IssuED OcroserR 1, 1969 CAL Missouri BOTAN! - CONTRIBUTIONS FROM THE GRAY HERBARIUM OF HARVARD UNIVERSITY Edited by Reed C, Rollins and Robert C. Foster No. CXCVIII A REMARKABLE NEW CRUCIFER FROM MEXICO By Reep C, Roiwins PETAL COLOR POLYMORPHISMS IN LEAVENWORTHIA (CRUCIFERAE) By |. Davi G. Lioyp THE GENUS KALLSTROEMIA ( ZYCOPHYLLACEAE) By . Duncan M. PorrTer PUBLISHED BY THE GRAY HERBARIUM OF HARVARD UNIVERSITY ~CAMBRIDGE, MASS. U. S.A. ~ 1969 Migs Bors, f TERS ye Tenia, OCT: 2 0869 ~ A REMARKABLE NEW CRUCIFER FROM MEXICO REED C. ROLLINS For over sixty years, the monotypic genus Ornithocarpa (Cruci- ferae) has been known from a single collection made in the state of Jalisco by C. G. Pringle in 1902. That collection was an ample one, and specimens were adequately disseminated so that the uniqueness of Ornithocarpa fimbriata Rose has been fully recog- nized and the authenticity of the species has never been ques- tioned. But the only published information on this unusual species is the rather terse description by Rose (1905) and the somewhat more expanded account in Die Pflanzenfamilien by Schulz (1936). No really new knowledge could be gained without either new collections or from observations on the growing plants in the field. From time to time, I have encouraged collectors working in Mexico to look for O. fimbriata and several attempts have been made to find the plants at the original locality near Constancia Station, east of Guadalajara. The most recent, unsuccessful attempt was that of Dr. Rogers McVaugh of the University of Michigan, who reported that much of the area where the plants might be expected to be found is now under cultivation. Because of the destruction of the original habitat, we had resigned our- selves to the possibility that this highly distinctive and most remarkable genus might never be more adequately known than was possible from the single collection made many years ago. Fortunately for those of us interested in the Cruciferae, a speci- men of Ornithocarpa showed up in a collection sent for identifica- tion by Dr. Peter H. Raven. The specimen, collected by Dr. Dennis E. Breedlove, was in early flower but the unmistakable fimbriate petals and the close match in over-all characteristics to specimens of O. fimbriata clearly placed it in the genus Ornitho- carpa. However, the young ovaries of the flowers had several ovules present instead of two, as in O. fimbriata, and the shapes of the very young siliques suggested a fruit quite unlike that of O. fimbriata as well. Even with flowering material only, we were nearly certain that an undescribed species was represented by the new collection, which came from the state of Durango. It was added good luck that Dr. Breedlove was returning to Mexico in the summer of 1967, and that he was willing to cooperate to 4 REED C. ROLLINS de. 1-3. Ornithocarpa torulosa. Breedlove 15888 from Durango, Mex. greenhouse grown plant showing rhizomes with young plantlets hore Fic. 2, chromosomes of ec cell, no 100 2° MM-yellow-centered uniflora _ sc >100 1 MM-yellow-centerec crassa cl si 8 6 QM-yellow-centerec i c2 si 8 M-yellow-centerec : c3 si 8 6 PM-yellow-centered + yellow c4 si 4 5 M-yellow-centerec ei c5 sc 9 4 PM-yellow-centered + yellow 6 c6 sc 1 1 MM-yellow-centere * c7 ie 2 3 PM-yellow-centered + yellow sf c8 sc 1 3 PM-yellow-centered + yellow i c9 sc 1 1 MM-yellow-centerec , cl0 sc 1 2 PM-yellow-centered + yellow sd cell sc 1 1 MM-yellow-centerec “i cl2 sc 1 ‘ M-yellow ° cel3 sc 2 1 MM-yello ef cl4 sc 1 1 MM-yellow-centered el5 sc 13. 1 MM-yellow alabamica a si 17 3 QM-yellow-centerec sc 14 3° MM-yellow-centerec . a3 sc ] 1 MM-yellow-centerec % a4 sc 11 1 MM-yellow-centerec . Russellville sc 1 2 PM-yellow-centered + orange-centered ns uscumbia sc 3. 1 MM-yellow-centerec exigua var. laciniata sc 1 1 MM-yellow-centerec . var. exigua sc >50 1 MM-yellow-centered “ var. lutea sc 5 1-~ MM-y aurea sc 10 1 MM-yellow 1 si = self-incompatible, sc = self-compatible. ? For those races of which only one or two populations were examined, these are the only known popula- -— = quasimorphic, PM = polymorphic, MM = monomorph = ai except one or two populations were strictly sr iN OE text. PETAL COLOR POLYMORPHISM IN LEAVENWORTHIA 15 but represent readily distinguishable ranges of flower color fre- quencies. MONOMORPHIC RACES: Seventeen races, distributed among all species except L. stylosa, are completely uniform, or almost so, in flower color (Table 2). Twelve races have yellow-centered flowers and five races have yellow flowers. More than three hun- dred populations of monomorphic races have been examined and only three contained any variation in flower color. In one popula- tion of L. torulosa, Rollins (1963) observed a few yellow-flowered plants among the plants with yellow-centered flowers. One of the fourteen counted populations of race a2 of L. alabamica con- tained a single plant with eye-intermediate flowers among the yellow-centered plants and another contained two plants with cream-pigmented flowers. QUASIMORPHIC RACES: Six races of L. stylosa, L. crassa and L. alabamica contain some populations which are strictly mono- morphic while others have the same morph in high frequency, but also include plants of one or more additional morphs in low frequencies. These races are described here as quasimorphic. The predominant flower color in five of these races is yellow-centered, but in the yellow-flowered race of L. stylosa the predominant color is yellow (Tables 2 and 3). Altogether, 44 of the 66 popula- tions of quasimorphic races examined contained more than one morph. In 41 of these, one color occurred in frequencies between 98 and 100 per cent. The predominant color occurred in less than 98 per cent of the plants in only three populations, which con- tained up to 24.6 per cent of the otherwise rare orange-pigmented morph. Thus, populations of the quasimorphic races characteristically contain two or more morphs, but only one of these is common. The occurrence of strictly monomorphic populations in these races shows that the quasimorphic races are not sharply distinct from the monomorphic races. Conversely, the three populations of the quasimorphic races c2 and c4 of L. crassa in which orange- pigmented flowers are relatively common may be described as polymorphic. But, in contrast to the polymorphic races, the pres- ence of two morphs in intermediate frequencies is not character- istic of races c2 and c4. In addition to the common morph, populations of the quasi- morphic races contain up to four rare flower colors. Most of the 16 DAVID G. LLOYD six morphs have been found in one or more populations of all six quasimorphic races (Table 3), but different populations of one race contain different rare morphs. Almost every possible combi- nation of the presence and absence of the rare colors occurs in the quasimorphic races, and their relative frequencies vary irregu- larly. A rare morph may arise periodically as a mutant, and persist for an indefinite time, depending on chance and the balance of selective forces operating on it. POLYMORPHIC RACES: All populations of six races contained two morphs in frequencies of at least three per cent, and usually more than 20 per cent. In five of these polymorphic races (c3, c5, c7, c8 and cl0 of L. crassa) the yellow and yellow-centered morphs were common (Tables 2 and 3). Some of the polymorphic L. crassa populations also contained one or more rare morphs in low frequencies. In the only known population of the Russellville race of L. alabamica, the yellow-centered and orange-centered morphs are common (Table 3). Except for races c3 and c5 of L. crassa, the polymorphic races are known from only one or a few populations. The frequencies of the morphs in races c3 and c5 were counted in populations occupying glade, pasture, roadside and corn-field sites. Many more populations of these races were observed than were actually counted. All of these consisting of more than a few dozen plants contained the yellow and yellow-centered morphs in considerable frequencies. The polymorphism in these races, therefore, persists in a wide variety of habitats. In many populations of the poly- morphic races, the morph frequencies were similar in 1961, 1962 and 1964. In the only polymorphic population in which exactly the same area was counted in two years, the ratios of yellow- centered to yellow to eye-intermediate morphs were determined from approximately one thousand plants, and were similar in both years (68.3:28.3:3.31 in 1961; 70.0:26.8:3.25 in 1962). The glade populations of the polymorphic races never occupy an area more than about 30 meters long, and the frequency of the morphs varies little throughout a glade. On secondary sites, populations which are more or less continuous for several acres contain the yellow and yellow-centered morphs throughout, but their relative frequency is locally variable. Such populations may change from predominantly yellow to predominantly yellow- centered over a distance of 20 meters or less. Two populations of TABLE 3. The ranges of morph frequencies in populations of quasimorphic and polymorphic Range of morph frequency (percentage) races No. popula- Yellow- ye-inter- Strip-inter- Orange- Cream- Species Race tions counted centered Yellow diat mediate pigmented pigmented stylosa white-flowered 12 99.0-100 0-0 0-0.3 0-0.5 01 0 tylosa yellow-flowered 14 0-0.7 99.0-100 0-0.7 0-0.5 0 -0.5 — rassa cl 8 98.9-100 0-0.9 GO. =. 061% O01 v3 morphic | crassa c2 ll 94.3-100 0-0.6 0-0.5 0-05 0-51 ue ete crassa c4 4 75.4-99.8 0-0.1 0-0.7 0 0-24, va alabamica al 17 8.2-100 0-1.6 0-0.2 0 0 0 crassa c3 8 41.8-91.3 7.9-58.2 0-3.3 + + ob Pol crassa c5 9 3.0-94. 4.6-97.0 0-0.9 0 0 ae = .. crassa c7 2 78.2-94.3 20.7-5.0 1.1-0.7 0 0 0 morphic ) cras c8 1 52.2 47.6 3 0 0 0 races lore cl0 1 69.1 30.9 0 0 0 alabamica Russellville 1 86.4 0 0 13.6 0 1 A zero indicates a morph has not been found in a race; a plus sign indicates a morph did not exceed 0.05 per cent in any of the populations d counted. VIHLYOMNAAVAT NI WSIHCHOWATOd HOTOO TV.Lad LI 18 DAVID G. LLOYD race c5 on uncultivated land in 1962 were divided into numerous, more or less discrete, sub-populations of varying size. The fre- quency of the morphs in these sub-populations varied from all yellow to all yellow-centered in an irregular pattern. Both of these populations were on formerly cultivated land and were probably continuous in previous years. Reduction of these populations to small scattered patches of plants may have resulted in genetic drift of allele frequencies and to loss of one allele in some sub- populations. us, within the limits described, pure populations of each of the 29 Leavenworthia races exhibit a restricted range of flower color frequencies. Six types of races can be distinguished (Table Monomorphic yellow (five races). Monomorphic aap (twelve races). Quasimorphic yellow (on Quasimorphic valet’ (fiv es). Polymorphic yellow plus Valltvecentered (five races). Polymorphic yellow-centered plus orange-centered (one race). 2 Om fe There is some overlap in morph frequencies between populations of different race types, but the six race types each have a charac- teristic, limited spectrum of morph frequencies. SECONDARY POLYMORPHISM Polymorphic populations of a different kind from those de- scribed above have recently arisen in L. crassa and L. stylosa, following the removal of forest and spread of populations from the original glade sites onto cultivated and waste land. The ‘white- flowered’ and ‘yellow-flowered’ races of L. stylosa were com- pletely, or almost completely, allopatric before the removal of forest, but glade populations of the two races approach each other over a broad front in the Central Basin of Tennessee (Rol- lins, 1963). Since the advent of agriculture, the two races have formed polymorphic populations in three areas in Wilson Co., Tenn. Although the micro-distribution of the two morphs in the hybrid areas is complex, there are a number of short clines where populations change from about 98 per cent yellow-centered to about 98 per cent yellow-flowered plants within a few hundred meters. In Morgan Co., Alabama, eleven races of L. crassa and two races of L. alabamica, each originally confined to one or a PETAL COLOR POLYMORPHISM IN LEAVENWORTHIA 19 few cedar glades, occur within an area of approximately ten square miles (Lloyd, 1965). Many of these races have now spread onto cultivated land, and on at least ten occasions have formed mixed, polymorphic populations. In both species, the secondary polymorphic populations contain the yellow and yellow-centered morphs. But, in contrast to the racially pure populations, the mixed populations show a complete gradation from yellow to yellow-centered populations, with all frequencies of the two morphs represented. DISTRIBUTION OF THE RACE TYPES The six racial types distinguished on the basis of petal color frequencies are not randomly distributed among the Leaven- worthia species or among the races in the complex species L. crassa and L. alabamica (Table 2). The most important factor influencing the petal color diversity of the races is the breeding system. The primitive breeding system in Leavenworthia is self- incompatibility with some pseudo-compatibility, as found at present in seven races of L. stylosa, L. crassa and L. alabamica [Tables 1 and 2, from data in Rollins (1963) and Lloyd (1965) J. The remaining 22 races are self-compatible, giving equally fre- quent fruit set on self- and cross-pollination. Self-compatibility has evolved at least six times in the genus and has been accom- panied by evolutionary trends in more than fifteen characters. The extent of evolution in these characters varies considerably in self-compatible races. In L. crassa and L. alabamica, the amount of spontaneous autogamous pollination in an insect-free greenhouse is least in the self-incompatible races and highest in races which show the greatest number of characters associated with self-compatibility (Lloyd, 1965). In general, the percentage of self-fertilization in natural populations of the races probably increases with increasing expression of characters associated with self-compatibility. There is a marked tendency for the number of flower color morphs found in a race to decrease as the adaptations to self- pollination and, presumably, the amount of inbreeding increase (Table 2). This trend is evident in the whole genus, but is more regular when the species or species groups are considered separ- ately. In the species with 15 chromosome pairs, the two races of 20 DAVID G. LLOYD L. stylosa, which are self-incompatible, have up to four and five flower colors per population respectively. The self-compatible species L. torulosa has two morphs, one of which was present in only one population. The species with flowers best adapted to autogamy, L. uniflora, has only plants with yellow-centered flowers. In L. alabamica (n=11), the only self-incompatible race, al, has up to three morphs in each population. Race a2 is self- compatible, but does not show any of the floral features usually associated with self-compatibility (Lloyd, 1965). Most popula- tions of race a2 are strictly monomorphic, as described above. The remaining self-compatible races have reduced flowers and other adaptations to self-pollination and are monomorphic, except for the one known population of the Russellville race. The four self-incompatible races in L. crassa (n=11), each have five or six petal color morphs. Race c5, which shows the least adaptation to autogamy among the self-compatible races, has four morphs. Races c6 to cl0, which show an intermediate loss of adaptations to cross-pollination and a gain of characters facilitat- ing self-pollination, have between one and three morphs. Races cll to cl5 are best adapted to self-pollination and are also strictly monomorphic. The four races of L. exigua (n=11) and L. aurea (n=—24), which have lost more of the adaptations to cross-pollination than any of the races of L. crassa or L. alabamica, are all strictly mono- morphic. In several phyletic lines, therefore, the number of morphs found in a race decreases as the facility for autogamous pollination increases. But it is noteworthy that all except one of the six poly- morphic races, the populations of which contain two common morphs, are self-compatible. Moreover, all of the glade popula- tions of the polymorphic races are small, usually containing less than two thousand plants. The polymorphic races therefore often exist in their natural habitat in small, inbred populations. The most extreme case of the maintenance of a polymorphism under such adverse conditions is the single existing population of race cl0 of L. crassa. This population is not only self-compatible, but has introrse anthers and automatically self-pollinates itself with considerable frequency in an insect-free greenhouse (Lloyd, 1965 ). In 1962 the polymorphic population consisted of 127 flow- PETAL COLOR POLYMORPHISM IN LEAVENWORTHIA 21 ering plants, which produced an estimated average of 1.68 flowers per plant. In 1964, the population contained about 60 small plants at the beginning of the flowering period. The yellow-centered plus orange-centered polymorphism is restricted to the Russellville race of L. alabamica, which is known from, and may well exist as, a single population. The other five polymorphic races, which have the yellow and _ yellow- centered morphs in all populations, are races of L. crassa and occur within a single area approximately three miles long by one mile wide in Morgan Co., Alabama (Lloyd, 1965). These races are distinguishable by minor, but consistent, morphological char- acters and each occupies one or a few cedar glades from which they have spread onto cultivated land. The polymorphism has the same genetic basis in at least three of the races (see below) and is restricted to this area. It is therefore probable that the yellow plus yellow-centered polymorphism in L. crassa has evolved only once and has been retained in the differentiation of the five polymorphic races. Six other races of L. crassa occur in the same small area. They are either monomorphic yellow or monomorphic yellow-centered and are, in general, more adapted to inbreeding than the polymorphic races. These monomorphic races have probably been derived from polymorphic ancestors by loss of one of the alleles. GENETICS Plants of several races of L. crassa, race al of L. alabamica and both races of L. stylosa, were grown in a greenhouse from seed collected from natural populations. In addition, the natural prog- eny of several plants of the rare morphs of races cl, c2 and c3 of L. crassa and race al of L. alabamica were grown. A number of crosses were made, and the F, plants grown. Many plants died and only small numbers from some of the families flowered. Very few families were taken to the second generation. CROSSES WITHIN POPULATIONS. Yellow-centered versus yellow: In the quasimorphic yellow- centered races cl and c2 of L. crassa, the natural progeny of yellow-centered plants were all yellow-centered. The natural prog- eny of four yellow-flowered plants were a mixture of plants with 22, DAVID G. LLOYD yellow flowers and plants with yellow-centered flowers, in approxi- mately equal numbers. F, and F, families from yellow-centered < yellow-centered crosses in race c2 consisted entirely of plants with yellow-centered flowers (Table 4). The families from yellow X yellow and yellow x yellow-centered crosses segregated for yellow and yellow-centered morphs. These results suggest that the difference between yellow and yellow-centered is determined at a single locus, that yellow is dominant to yellow-centered, and that the rare yellow-flowered plants are heterozygous. In the polymorphic races c3, c5 and c8 of L. crassa, yellow- centered & yellow-centered and yellow-centered yellow crosses produced F;, and F, families in which the plants were either all yellow-centered or segregated for both morphs (Table 4). Yellow * yellow crosses produced only yellow-flowered plants. The results indicate that the alleles of one locus determine the differ- ence between the two flower colors, that the three genotypes occur in nature, and that yellow-centered is dominant to yellow. Although the genetic analysis of yellow-centered versus yellow flowers in these races is incomplete, it is clear that the genetic basis of the two color patterns is different in the quasimorphic and polymorphic races. Also, it may be noted that neither of the intermediate pigment patterns appeared in any cross, so these patterns are not produced by heterozygotes for alleles determin- ing the uniform and centered patterns. Intermediate patterns: The natural seed of four strip-intermedi- ate and two eye-intermediate plants of the quasimorphic yellow- centered races of L. crassa and L. alabamica were collected. The progeny were grown and in each case contained approximately equal numbers of yellow-centered plants and intermediate plants of the same type as the seed parent. A strip-intermediate yellow-centered cross in race c2 produced four yellow-centered and four strip-intermediate plants. This information suggests that the intermediate patterns, like yellow, may be dominant to yellow- centered in the quasimorphic races. It is not known whether the two intermediate patterns are determined by alleles of the same locus or if homologous loci are involved in all quasimorphic races of L. crassa and L. alabamica, The natural progeny of three eye-intermediate plants of the polymorphic races c3 and 5 of L. crassa and the F, progeny of a yellow-centered eye-intermediate cross (race ¢3) were in each PETAL COLOR POLYMORPHISM IN LEAVENWORTHIA 23 TaBLE 4. The genetics of yellow-centered versus yellow flowers in four races of L. crassa. Race Parents First generation Second generation Number Number Number umber Cross Description ¥.C. yellow Cross yc. yellow eX 3 0 c2 623-1 « 621-8 yellow X y.c. 16 14 +yellow x ia 4 8 .c. x yellow 12 9 621-8 x 621-9 y.c. X y.c. 17 0 621-17 x 621-16 wc. X yc. 16 0 623-1 «x 623-1 ella selfed 3 1 1290 «x 1291 y.c. X yellow 13 13 is SL Ve ll 2 c3 121-7 121-12 ——-y.c. X yellow 23 0 ae eo : 121-7 x 121-7 y.c. selfed 8 0 121-12 x 121-12 yellow selfed 0 9 Oe SVs 19 4 635-14 x 635-9 y.c. X yellow 14 12 Fellow’ x aioe 6 9 635-13 x 635-14 LX Ye. 20 0 635-9 x 606-15 pen X yellow 0 32 605-6 x 602-2 yellow X yellow 0 19 635-17 635-19 5 4 c5 632-6 x 632-1 y.c. X yellow 5 3 632-8 « 632-6 yc; X Y.c. 9 3 632-6 x 632-6 y.c. selfed 3 0 632-1 x 632- yellow selfed 0 13 c8 631-12 «x 631-21 y.c. X yellow 10 6 631-21 x 631-21 y.c. selfed 1 2 case a mixture of the yellow, yellow-centered and eye-intermedi- ate morphs. The eye-intermediate phenotype may be controlled by a dominant gene at a separate locus from, and epistatic to, the alleles controlling the yellow plus yellow-centered polymorph- 1sm. CROSSES BETWEEN RACES. A number of crosses between plants of different races were made, using only plants with yellow or yellow-centered flowers. Flowering F, plants were obtained in 13 families from crosses between L. crassa races and three families from crosses between the two L. stylosa races. The outstanding feature of the crosses between races is that, in most families, some or all of the hybrids had flowers with neither the centered nor the uniform pigment patterns of the parents, but with an intermediate pattern; that is, dominance was often incomplete. In both species, there was a marked tendency for the intermediate flowers to resemble the dominant pigment pattern least in families in which the propor- tion of plants with intermediate pigment patterns was highest. In 24 DAVID G. LLOYD TABLE 5. Petal and a8 measurements of yellow-centered and yellow flowers of seven . crassa races! Difference between morphs? Av. pistil Av. notch Av. petal length length length Pistil: Notch: Pistil: Notch: mm mm mm Petal Petal Petal Petal Race Population (1) (2) (3) (1) + (3) (2) +(3) cl 171 5.34 1.32 12.20 438 .1083 — .014 — .006 5.35 1.35 11.83 452 .1139 954 5.48 1.03 11.89 461 .0868 — .058 + .016 5.54 0.75 10.67 519 .0707 c2 354? 5.45 0.95 12:13 449 .0789 — .009 — .006 5.25 0.97 11.46 .458 .0849 354 4.81 1.05 11.60 Al4 .0902 — .031 +.011 4.88 0.87 10.98 445 .0794 368 4.61 1.16 11.07 A17 .1050 — .046 +013 4.66 0.93 10.06 463 .0923 c3 89° 5.97 1.39 12.46 .480 1122 — .064 + .021 6.34 1.06 11.66 544 .0909 89 5.65 1.33 IL .507 .1195 — .062 + .027 5.67 0.92 9.95 .569 .0924 61 6.46 1.26 12.47 .518 .1014 — .080 + .009 6.82 1.06 11.41 598 0925 792 6.52 0.97 11.80 DOG .0828 —.091 + .010 7.03 0.80 10.93 .644 .0732 cd 100 6.18 1.47 12.43 497 .1184 — .063 + .016 6.25 1.14 11.16 .560 .1025 58 6.26 1.45 12.71 A492, 1143 — .074 + .024 6.32 1.00 A117 .566 .0899 96 6.18 LZ 11.49 538 .1021 — .058 + .002 6.67 |e | 11.18 .596 .0997 86 5.91 Le i315 .530 .1005 — 074 + .009 6.04 0.92 10.00 .604 .0912 c7 361 3.92 0.84 9.28 422 .0899 — .044 + .025 3.95 0.55 8.48 466 .0648 927 4.18 0.83 10.03 A17 .0824 — .052 +.014 4.26 0.62 9.09 .469 0684 c8 ys y 5.16 0.76 9.45 546 .0804 — .088 + .030 5.45 0.44 8.61 634 .0508 WZ 5.16 0.93 10.04 514 .0929 — .077 + .026 5.31 0.60 .98 591 .0672 cl0 698 5.03 0.88 10.03 501 .0884 — .065 + .012 5.04 0.68 8.93 .566 .0760 1 The measurements and ratios ~ E droseiede centered flowers of each sample are shown above the corre- sponding figures for yellow flower ? Ratio for yellow-centered flo Owers minus ratio for yellow oe 3 Populations 354, 89 and 72 were sampled in 1962 and 1 PETAL COLOR POLYMORPHISM IN LEAVENWORTHIA 25 the L. crassa crosses, the intermediate flowers resembled the naturally occurring eye-intermediate pattern, but in L. stylosa the intermediate flowers resembled the strip-intermediate pattern. The greatest variability in the pigment pattern of hybrids between races was noted when a heterozygous yellow-centered plant of the polymorphic race c3 of L. crassa was crossed with a heterozygous yellow plant of the quasimorphic race c2. The F, family of 15 plants consisted of four plants with yellow-centered flowers, one yellow-flowered plant, six plants with eye-intermedi- ate flowers (the extent of pigmentation varied between plants) and four plants with variable flower colors. The variable plants produced yellow-centered, yellow and a full range of intermedi- ate flowers throughout their flowering period, and in some flowers the extent of pigmentation varied among the four petals (Fig. 2). Scapose flowers were mostly yellow-centered or nearly so. Most racemose flowers were uniformly or almost uniformly yellow. FLOWER MEASUREMENTS Yellow-centered and yellow flowers of seven races of Leaven- worthia crassa were compared to determine whether there were any differences between the flowers in addition to the pigment patterns. Eighteen samples from 15 natural populations (Table 5) were collected by taking one flower from 25 plants of each morph. The pistil length, the length of one petal and the length of one petal notch (the difference between the petal length and the petal length to the base of the terminal notch) were measured. The averages for the three measurements were calculated for the two morphs of each sample. The two morphs differ almost consistently in all three measure- ments (Table 5, Fig. 3 and 4). Yellow-centered flowers have longer petals in all 18 samples, longer petal notches in all but one sample of race c2, and shorter pistils in all but one sample of race cl and one sample of race c2. Despite the differences between the two morphs and the variation between samples of the same race, the points for both morphs of a race tend to cluster, as shown in Fig. 4 and 5 and to separate from those of other races. That is, there are racial differences in the three measurements, which are often greater than the differences between morphs of the same 26 DAVID G. LLOYD Fic. 2. Four flowers of one hybrid plant with variable flower color from a cross between a yellow Phot: plant of race c3 of L. crassa and a yellow plant of race c2. Note the variation between petals distribution, in the lower right flower n pigment PETAL COLOR POLYMORPHISM IN LEAVENWORTHIA 27 L Hi | PISTIL LENGTH (mm.) PETAL NOTCH LENGTH (mm.) 3 T ow FIG, 4 FIG, 3 Od 4 n 4 1 eS 1 B ; = 7 12 3 ° n 12 : PETAL LENGTH (mm.) w w T uw o T 1 g T § nh FIG.6 PISTIL LENGTH + PETAL LENGTH DIFF. BETWEEN FORMS (PISTIL + PETAL) 4 s ' i i ” L i 04 +06 “08 “10 12 “14 sae ° +01 +02 703 NOTCH LENGTH + PETAL LENGTH DIFF. BETWEEN FORMS (NOTCH + PETAL) 3 to 6. Floral measurements and derived ratios of yellow and yllow-centered flowers in seven L. crassa races. In Figs. 3 to 5, lines connect ints for the mo from the same collection; the figures, indicating e poi r ye . d yellow-centered flo - _ “ae ye i am the difference in pistil length divided by 28 DAVID G. LLOYD race. Races cl and c2 have similar measurements in all three characters. Races c3 and c5, which are morphologically very sim- ilar, are also indistinguishable in the three measurements. There are, therefore, parallel differences between the morphs in the seven races, despite considerable evolution in the characters measured. Moreover, the genetical basis of yellow versus yellow- centered variation is different in the quasimorphic and poly- morphic races. The morph differences in floral measurements probably represent pleiotropic effects of the alleles determining pigment pattern, rather than the effects of genes closely linked to the loci determining pigment pattern. It is also apparent in Fig. 3 and 4 that the three measurements are positively correlated. To obtain characters which are inde- pendent of flower size, the average pistil length divided by average petal length, and the average notch length divided by average petal length were calculated for both morphs of each sample (Table 5). The pistil:petal ratio is consistently greater for yellow flowers than for yellow-centered flowers in all seven races. The notch:petal ratio is smaller for yellow flowers than for yellow-centered flowers in all but two of the samples—again, one sample of race cl and one of race c2 are anomalous. When the two ratios are graphed against each other ( Fig. 5) the points for a race again tend to separate from points for other races. That is, the differences between the morphs in the ratios are common to all races, although the ratios themselves vary considerably een races. The differences between the morphs in the two ratios are graphed in Fig. 6. The races do not separate from each other completely, but it is apparent that the amount of the difference tween the morphs also varies between races, The points for the quasimorphic races cl and c2 are generally closer to the TaBLe 6. Average number of pollen grains in yellow and yellow-centered flowers of L. crassa Number of pollen grains « 1000 ace c5 Race c3 ace c5 Race c8 Flower color Popn. 37 Popn. 58 Popn. 100 Popn. 72 Yellow-centered 53.0 31.6 37.4 41.0 Yellow 43.8 29.4 35.0 25.2, origin than are the points for the polymorphic races. Thus the differences between yellow and yellow-centered flowers are less PETAL COLOR POLYMORPHISM IN LEAVENWORTHIA 29 in the quasimorphic races, although the flowers are larger in these than in the polymorphic races. The average number of pollen grains per flower in five yellow and five yellow-centered flowers was estimated for four popula- tions of the polymorphic races c3, c5 and c8 (Table 6). In all four populations, the average number of pollen grains was found to be higher in yellow-centered flowers than in yellow flowers. The yellow and yellow-centered morphs in L. crassa differ in average measurements affecting three floral organs: the petals, pistils, and stamens, as well as in the pattern of petal pigmenta- tion. There are, however, no consistent differences between the two morphs in the number of ovules per flower, anther length, or the percentage of successful self-pollinations (Lloyd, 1965 and unpublished thesis ). NUMBER OF FLOWERS The number of flowers produced by naturally growing plants with yellow and yellow-centered flowers was compared in 13 samples, taken from nine populations of the closely related poly- morphic races c3 and c5 of L. crassa. The samples consisted of 50 plants of both morphs taken from a transect across a population at the end of the flowering season. The average numbers of flowers produced by the two morphs and the combined average were TABLE 7, The average and relative numbers of flowers produced by plants with yellow- centered and yellow flowers in samples from natural polymorphic populations Average number of flowers* Rel. no. flowers Yellow- si entered Yellow Y-centered + yellow Race Year Hstdgas’ ae 7 (1) (2) and yellow (=) 3 1961 61 glade 2.59 3.18 2.89 0.816 c3 1962 61 glade 3.74 KY f 0.802 c3 1962 OL P 5.24 5.46 1.084 c3 1962 89 glade 5.72 5.78 5.15 0.990 c3 1962 89 lade 8.10 7.38 0.822 1961 70 roadside 8.28 7.28 7.78 1.138 c5 1961 36 pasture 8.97 8.88 8.92 1.010 c3 1961 89 glade 10.66 12.46 11.56 0.856 cd 1962 948 cornfield 34 14.98 14.66 0.957 cd 1962 944 cornfield 19.20 19.54 19.37 0.983 1962 36 P e 21-72 18.98 1.144 cS 1962 58 cornfield 28.68 21.28 24.98 1.348 c3 1962 88 cornfield 41.42 35.18 38.30 1.177 1 The samples are listed in the order of increasing average number of flowers per plant. 30 DAVID G. LLOYD calculated for each sample (Table 7). The samples were taken from a variety of habitats and the combined averages vary widely, from 2.89 to 38.30 flowers per plant. The fruits of all plants of one morph in a sample were mixed together, so it is not possible to compare statistically the flower production of the morphs in a sample. The relative number of flowers produced by the morphs has been compared by calculat- ing the number of yellow-centered flowers divided by the number of yellow flowers (Table 7). This varies from 0.80 to 1.35. Thus, there is no consistent difference between the morphs in flower production. But when the logarithm of the relative number of flowers is plotted against the logarithm of the average num- ber of flowers per plant (F ig. 7), the points for the thirteen samples have a bivariate normal distribution and are significantly correlated (r = + 0.67, P = .02-.01). The regression of the logarithm of the relative number of flowers (Y) on the logarithm of the average number of flowers (X) was calculated. When the plants produce an average of three flowers each (near the lower limit of the samples), the relative number of flowers, reconverted from log- arithms, has an estimated average of 0.84, with 95 per cent confidence limits of 0.73 and 0.98. That is, plants with yellow- centered flowers produce significantly fewer flowers and the reduction is estimated to be 16 per cent of the flower production of the yellow morph. When the plants produce an average of 30 flowers each (near the upper limit of the samples ), the average relative number of flowers is estimated at 1.16, with 95 per cent confidence limits of 1.02 and 1.38. That is, plants with yellow- centered flowers produce significantly more flowers than yellow- flowered plants and have an estimated advantage of 16 per cent of the flower production of the yellow morph. In races c3 and c5, therefore, under poorer growing conditions the yellow morph produces more flowers, but under more favor- able conditions the yellow-centered morph produces more flowers. The estimates of the relative number of flowers suggest that the advantage of each morph under opposite extremes is considerable. INsEcT Visits Observations were made to determine whether the insects visiting Leavenworthia flowers are equally attracted to the most PETAL COLOR POLYMORPHISM IN LEAVENWORTHIA 31 a ° ) RELATIVE NO. OF FLOWERS (y.c. + yellow) : (2) 0-70 1 l 6 10 AVERAGE NO. OF FLOWERS Fic. 7. Regression of the relative number of flowers produced by yellow and yellow-centered morphs (Y) on the average number of flowers produced both morphs (X) in polymorphic populations of races c3 and c5 of L. crassa. The scale of both axes _is logarithmic. The vertical lines show the 95 per cent confidence limits of Y when X = 3.0 and 30.0. a2 DAVID G. LLOYD common petal colors, yellow, yellow-centered and eye-intermedi- ate. The visits of insect species to the three morphs were compared with the frequencies of these morphs in four plots on two popu- lations of the polymorphic race c3 of L. crassa. Population 89 occupied a pre-agricultural glade site in which the yellow- centered morph was more common than the yellow morph, and plants with eye-intermediate flowers were more common than in any other Leavenworthia population. Population 88 occupied an adjacent corn field in which yellow-flowered plants were most common, and plants with eye-intermediate flowers were absent. In both populations, the plants were small and rarely produced more than one or two flowers at a time, and the morphs appeared to be randomly dispersed. Plots were marked out, by a string line between pegs, to form squares enclosing a thousand or more flowers. The frequencies of e flower colors were recorded in diagonal transects across the plots (Table 8). Insect visits to the morphs within a plot were recorded on the same day as the flowers were counted. HONEY BEES: On both Populations 88 and 89, honey bees (Apis mellifera L.) were the most frequent flower visitors, comprising about 70 per cent of the insects on these populations in both 1961 and 1962. The percentages of their visits to the morphs are similar to the flower frequencies in the four plots. Considering yellow- Taste 8. The frequencies of morphs and of insect visits to the morphs in four plots Plot Number No. insect Totalno. Population Flowers indi- visits or and year and insects viduals flowers centered Yellow 89, 1961 Flowers ~ 126 60.3 ney S 9 214 62.6 30.8 Bombylius oS: 185 94.1 89, 1962 wers - 74.7 23.0 Honey bees 9 353 74.2 22.7 Solitary bee-1 5 168 73.2 21.4 Solitary bee-2 oie 74.1 23.5 Solitary bee-3 4 79 70.9 24.1 Sol. bee-total 14 409 73.1 22.7 Bombylius 3 122 100.0 0.0 Anthocaris I 147 68.0 26.5 89, 1962 wers -_ 2 65.7 30.2 Honey bees 4. Ws 60.8 28.4 Anthoca 2 70.4 26.0 88, 1961 Flowers - 1031 41.8 58.2 Honey 1 40.0 60.0 Bombylius Ss 26 85.3 14.7 Percentages of flowers and visits Eye- inter- medtate PETAL COLOR POLYMORPHISM IN LEAVENWORTHIA 33 centered and yellow flowers only, the proportions of flowers and honey bee visits did not differ significantly in any of the four plots (x?<0.50, P>.05 in all plots). The x? tests can be combined by the relationship d =3/\/d.f. (Simpson et al., 1960), giving d = 0.17, P>.05. In contrast, the frequency of honey bee visits to eye-intermediate flowers exceeds that of the frequency of these flowers in all three plots containing this morph. The excess of visits to eye-intermediate flowers, compared with visits to yellow and yellow-centered flowers combined, is significant in Plot 3 (x? = 10.81, P<.01) and in the three plots combined (d = 2.42, P<.01). SOLITARY BEES: Twenty species of solitary bees, the natural pollin- ators of Leavenworthia flowers, were collected on Populations 88 and 89 and nearby populations (Lloyd, 1965). These com- prised about 15 per cent of the insect visitors to Populations 88 and 89. The visits of the three most common species were re- corded in Plot 2 (Table 8). The proportions of visits to yellow and yellow-centered flowers are not significantly different among the three bee species (? = 0.02, d.f. = 2, P>.05). Combining the counts from the three species, the relative number of visits to yellow and yellow-centered flowers did not differ significantly from the frequency of the flowers (x? = 0.005, P>.05). All three species visited eye-intermediate flowers in frequencies above that of the morph in the plot. The higher frequency of visits to eye- intermediate flowers is not significant (7 = 2.52, P>.05), but the total number of solitary bee visits recorded on eye-intermediate flowers was only 17. piPTERA: Eight Dipteran species were collected on Leavenworthia flowers in the vicinity of Populations 88 and 89. Bombylius major L., one of the most common of these, is the only fly species which moves from flower to flower rapidly enough for visits to the morphs to be counted. The visits of several Bombylius individuals were recorded on Plots 1, 2 and 4 (Table 8). Bombylius flies visit very few yellow flowers. In Plot 2, three individuals did not visit any yellow flowers, but in Plots 1 and 4 Bombylius individ- uals visited. a few yellow flowers. The preference of Bombylius for yellow-centered instead of yellow flowers is highly significant in all plots (x? = 48.28, 34.10, 150.00 in Plots 1, 2 and 4 respective- ly, P<.001 in all tests). Bombylius also visited very few eye- intermediate flowers. The visits of Bombylius individuals to 34 DAVID G. LLOYD yellow-centered and eye-intermediate flowers were compared with the flower frequencies by exact 2 x 2 contingency tests. The proportion of visits to eye-intermediate flowers was significantly below the proportion of the flowers themselves, in both Plot 1 (P = .014) and Plot 2 (P = .034). Thus Bombylius individuals favor yellow-centered flowers over both yellow and eye-intermedi- ate flowers. This preference was noted on many occasions other than those of the exact counts described here, and seems to be a constant feature of Bombylius visits to polymorphic Leaven- worthia populations. No counts were made of the visits of other Diptera species (Syrphidae and Stratiomyidae) to the Leavenworthia morphs. But they appear to visit the morphs indiscriminately and certain- ly do not show a marked preference for yellow-centered flowers. LEPIDOPTERA: Several species of Lepidoptera occasionally visit Leavenworthia crassa flowers. The visits of the most common species, Anthocaris genutia (Pieridae), to the three morphs were recorded in Plots 2 and 3 (Table 8). Considering the yellow and yellow-centered flowers only, the relative numbers of the flowers and the visits of A. genutia did not differ significantly in either Plot 2 (x? = 1.25, P>.05) or Plot 3 (x? = 0.48, P>.05). More- over, the relative numbers of eye-intermediate flowers and yellow plus yellow-centered flowers did not differ significantly from the relative numbers of A. genutia visits in either Plot 2 by? ox BS). P>.05) or Plot 3 (P = 1.00, since the frequencies of flowers and visits could not be closer). A. genutia, therefore, appears to visit the three morphs at random. Discussion Within the limits described, the populations of a Leavenworthia race are similar in the kinds and frequency of the petal colors they contain. However, the spectrum of morph frequencies differs greatly between races. Many factors interact to determine racial differences in morph frequencies. These include breeding systems, environmental variation, allelic differences, pleiotropy or linkage relationships of the alleles and the genetic background. The difference between races in morph frequencies may be due, in part, to the genes determining petal color. There is little infor- mation indicating whether a petal color is determined by the same PETAL COLOR POLYMORPHISM IN LEAVENWORTHIA 35 allele in different races. In L. crassa, yellow is dominant to yellow- centered in the quasimorphic races, but recessive to yellow- centered in the polymorphic races. The incomplete dominance of the yellow and yellow-centered forms in crosses between races indicates that dominance relation- ships in each population are not intrinsic properties of the alleles, but depend on polygenic modifiers, which differ between races (cf., Harland, 1936; Clarke and Sheppard, 1963). The canalized developmental pathways, leading to one or another of the pigment patterns, are disturbed in the mixed genetic background of hy- brids. The appearance, in the hybrids, of intermediate pigment patterns, similar to those occurring in natural populations, raises the question of the relationships of the intermediate patterns to the more common centered and uniform patterns. The results of progeny tests and crosses indicate that in L. crassa the intermedi- ate patterns are produced by different alleles, and probably at a different locus, from the yellow versus yellow-centered variation. Moreover, in both quasimorphic and polymorphic races, the fre- quency of the intermediate morphs varies independently of the ratio of yellow to yellow-centered plants. These results suggest that the intermediate morphs are not directly involved in variation in the frequency of yellow and yellow-centered morphs, and that the resemblance between the intermediate hybrids and the naturally occurring intermediate patterns is fortuitous. The breeding systems of the populations have had a pervasive effect on genetical variability at loci which determine flower color. The evolution of monomorphism from a polymorphic or quasi- morphic condition has occurred in a number of phyletic lines, together with the evolution of characters facilitating self-fertiliza- tion. The loss of all but one morph in these races of Leavenworthia may be attributed to increased inbreeding (cf., Baker, 1953; Grant, 1958; Jain and Marshall, 1967). The breeding systems can account for many of the racial differ- ences in the numbers of morphs, but not which morphs are present or their frequencies. Moreover, few of the differences between races can be explained by environmental variation. Populations of the same race have similar morph frequencies, even when they occupy a diversity of habitats. Conversely, races with different morph frequencies occupy similar habitats. In the yellow plus yellow-centered races of L. crassa, the poly- 36 DAVID G. LLOYD morphism has persisted through the differentiation of five races, despite frequent self-fertilization and the small size of glade populations. In the quasimorphic races, the repeated occurrence of the rare petal colors in numerous populations indicates that they frequently persist for long periods in a population. Thus, in both quasimorphic and polymorphic populations, there is a bal- ance of mutation and selective forces controlling the frequency of the alleles which determine petal color variation. Ford (1964) defined a polymorphism as “the occurrence together in the same locality of two or more discontinuous forms of a species in such proportions that the rarest of them cannot be maintained by re- current mutation.” If Ford’s definition is applied strictly, almost all populations which have genetically determined discontinuities would be described as polymorphic. There is no non-arbitrary frequency for two forms beyond which they can be said to be polymorphic. However, in Leavenworthia, the distinction between the population structures of quasimorphic and polymorphic races can be recognized by defining a polymorphism as the occurrence of two or more discontinuous forms in intermediate frequencies in a population. A lower limit of three per cent for two poly- morphic petal colors almost consistently separates the populations of quasimorphic and polymorphic races, and allows the two types of races to be conveniently distinguished. The recognition of a polymorphism, based on this definition, is arbitrary. However, it is the criterion generally used to decide whether or not the pres- ence of two or more allelic forms in a population constitutes a polymorphism. Some of the selective forces maintaining two alleles in inter- mediate frequencies in the yellow plus yellow-centered poly- morphism in L. crassa are known. Differences between the morphs in flower production probably contribute toward the mainte- nance of the polymorphism, since flower production is a direct component of fitness, and the morphs are each favored under opposite conditions. In both glade and secondary populations, the size of the plants varies considerably throughout a population and from year to year (Lloyd, 1965). Disruptive selection for the two alleles may help to keep them both in a population, but the spatial and temporal heterogeneity of the environment is probably too erratic for this alone to maintain the polymorphism, especially in the small glade populations of the more inbred races. PETAL COLOR POLYMORPHISM IN LEAVENWORTHIA 37 There is no clear association between the size of the plants and morph frequencies in polymorphic populations. Glade popula- tions usually have much smaller plants than populations on culti- vated fields, but the yellow and yellow-centered morphs are equally common in both habitats. Two factors may prevent a close association between average plant size and morph frequency. The two morphs, and not the three genotypes, were compared in flower production. The numbers of flowers produced by the dom- inant homozygote and the heterozygote, which are phenotypically indistinguishable, may have a major effect on morph frequencies. Secondly, the spatial and yearly variations in plant size probably prevent uniform, stable equilibrium frequencies from being main- tained throughout a population. In extreme cases, reductions in plant number and plant size in a population may allow random genetic drift in allele frequencies. The relative flower production of the yellow and yellow- centered morphs may determine which of them has been selected in monomorphic races. In L. crassa, three yellow-centered races and three yellow races have a monomorphic condition which is probably derived from a previous polymorphism. In general, the monomorphic yellow-centered races are less well adapted to au- togamy than the yellow races. Similarly, in L. exigua, the yellow- flowered var. lutea has a more advanced breeding system than the two races with yellow-centered flowers. In general, the more inbred races occupy poorer glade sites than those less well adapt- ed to autogamy (Lloyd, 1965). The yellow-centered races may have become monomorphic under relatively favorable conditions, when the yellow-centered morph has a higher flower production. The monomorphic yellow races may have become so under harsh- er conditions which favor the yellow morph, and a regular in- breeding system of reproduction. The visual appearance of the yellow and yellow-centered flow- ers does not seem to play an important role in maintaining the polymorphism, or in determining morph frequencies. The two color patterns appear to be equally attractive advertisements for bees, the only important pollinators of Leavenworthia flowers. However, the possibility exists that one or another morph may be preferred under other conditions than those prevailing when the counts were made. Bees may also visit a morph excessively when it is uncommon; the preference of bees for the infrequent 38 DAVID G. LLOYD eye-intermediate flowers may contribute to the persistence of this morph in many populations. The preponderance of Bombylius visits to yellow-centered flowers is not an important factor con- trolling morph frequencies, since Bombylius is a minor visitor and an ineffective pollinator. The differences between yellow and yellow-centered flowers in floral measurements are unlikely to have appreciable direct effects on the reproductive success of the morphs. They indicate, how- ever, that the morphs differ in a number of physiological proc- esses, either through pleiotropic action of the alleles or linkage to other loci, which may affect the relative fitness of the genotypes. The yellow plus yellow-centered polymorphism of L. crassa races has persisted through the differentiation of five races in small glade populations whose plants are frequently self-fertilized. Regular inbreeding, genetic drift, and fluctuations in the relative flower production of the morphs would eventually lead to the fixation of one allele. There must be a selective force operating on the alleles which maintains them both under a variety of environ- mental conditions. Overdominance, at or near the loci responsible for petal color polymorphism in Leavenworthia, may explain the persistence of the two alleles in intermediate frequencies. Hayman (1953) has demonstrated that two alleles can persist in intermedi- ate frequencies, in a population which reproduces by a mixture of self-fertilization and random mating, if the selection coefficients of the two homozygotes are not too dissimilar. Allard and co- workers (e.g., Jain and Allard, 1966) have explained persistent polymorphism in regularly inbreeding species on the basis of heterozygote advantage associated with segments of chromo- somes. The distribution and frequency of the morphs in Leavenworthia races cannot be fully explained by the results described above. But it is apparent that many factors interact to determine the floral diversity of Leavenworthia populations. The persistence of a polymorphism in some regularly inbreeding races, and the esti- mates of the relative number of flowers produced by the morphs, indicate that powerful selective forces are operating to maintain the polymorphism. SUMMARY In natural populations of the 29 geographic races of seven Leavenworthia species, three pigments and four patterns of pig- PETAL COLOR POLYMORPHISM IN LEAVENWORTHIA 39 ment distribution are found in the petals. The range of frequencies of the petal colors (morphs ) in each race is described, and three types of race are recognized—monomorphic, quasimorphic (one morph predominates and one or more additional morphs occur in low frequencies in some populations) and polymorphic (two morphs common in all populations). The number of morphs in a race tends to decrease as the adaptations to cross-pollination decrease and those to self-pollination increase; that is, genetical variability decreases as inbreeding increases. In polymorphic races of L. crassa, yellow flowers are recessive to yellow-centered flow- ers; in quasimorphic races yellow is dominant. In crosses between races, but not in crosses between plants of the same population, the yellow and yellow-centered morphs often show incomplete dominance. In one cross, some of the hybrid plants are variable in flower color. In Leavenworthia crassa, yellow and yellow-centered flowers differ in average petal, petal notch and pistil lengths, and derived ratios and in the average number of pollen grains per flower. In polymorphic races of L. crassa, plants with yellow-centered flow- ers produce fewer flowers under adverse conditions, and more flowers under favorable conditions than yellow-flowered plants. The visits of several insect species to three morphs are compared with the frequencies of the morphs in natural polymorphic popu- lations. Some insect species visit one or another petal color exces- sively, but this is probably not an important factor controlling morph frequencies. The roles of breeding systems, flower production, and spatial and temporal heterogeneity of the habitat in determining morph frequencies are discussed. None of the known selective forces adequately explain the persistence of polymorphism in small inbred populations. Overdominance, at or near loci controlling polymorphic variation, may maintain the polymorphism. ACKNOWLEDGEMENTS Professor Reed C. Rollins provided invaluable assistance and encourage- ment throughout this study, part of a Ph.D. thesis at Harvard University. Drs. R. S. Bigelow and J. B. Hair kindly read and criticized a draft of the cript. manus LITERATURE CITED Baker, H. G. 1953. Race formation and reproductive method in flowering plants. Symp. Soc. Exp. Biol. 7: 114-145. 40 DAVID G. LLOYD CiarkE, C, A. a . M. SHEPPARD. 1963. Interactions between major genes cae in the determination of the mimetic patterns of Papilio ardanus Evolution 17: 404 Danay, H. . Gene frequencies in wild populations of Trifolium repens. VV. Mechanism of natural selection. sng 20: 355-365. Epuinec, C., H. Lewis anp € M. Batu. 1960. The re aoe. and seed storage: . study in population penriey Evolution - Forp, E. B. 1964. Ecological Genetics. Methuen a Lo an Grant, v. 1958. The regulation of recombination in Seats Cold Spring Harbor r Symp. a Biol. 23: 337-363. Harvanp, S. C. 1936. The genetical conception of the species. Biol. Rev. Camb. Phil. Soe, ‘Li: 83-1 Hayman, B. I. 1953. Mixed selfing and random mating when homozygotes -192. Hovanitz, W. 1953. 3. Polymorphism and evolution. Symp. Soc. Exp. Biol. 7: 238-253, seam & ve 1955. er er and evolution. Heredity Jain, S. ND R. W. Atiarp. 1960. Population fidion in ne self- vs ted species. I. Evidence for on "oe in a closed population of barley. Proc. Nat. Acad. Sci. 46: Jatn, S. K. anp D. R. MarsHALL. idl Population peat in ‘predominant ‘celt-qcllingted species. X. Variation in natural populations of Aven fatua and A, barbata. Amer. Rtas. 101: 19-33. JONEs, D. A. 1966. On the polymer iis of cyanogenesis in Lotus cornicu- latus. I. Selection of animals. Canad. Jour. Genet. and Cytol. 8: 556-567. 967. pebcocslanid plants and natural populations. Science Progress 55: 379-400. Josui, B. C. anp S. K. Ph - 1964. Clinal variation in natural populations of Justicia simplex.‘ r. Natur. 98: -125. Rotuins, R. C. . The evolution and coi ca of Leavenworthia i : 1-98. Smupson, G. G., A. Roz aNp R. C. Lewontin. 1960. Quantitative Zoology. Harcourt, Brace and Co., New York. THE GENUS KALLSTROEMIA (ZYGOPHYLLACEAE ) Duncan M. Porter! My interest in the Zygophyllaceae dates from 1959 (at Stanford University ), when I began a taxonomic study of the family as it occurs in Baja California, Mexico. As I became more familiar with the family, it became increasingly obvious that the genera under investigation were badly in need of taxonomic revision, although their species in Baja California were relatively distinctive. I chose to study Kallstroemia because it appeared to be the New World genus most in need of revision. In addition, it is the largest genus of the Zygophyllaceae in the New World, elsewhere being sur- passed in number of species only by Fagonia, Tribulus, and Zygophyllum. Such statements as: “Serd necessario hacer una revisién minuciosa de las especies centro y norteamericanos para estab- lecer el valor de ellas.” (It will be necessary to do a thorough revision of the Central and North American species in order to establish their validity.) (Descole, et al., 1939, p. 221); “There is some difference of opinion as to how the species of this genus should be defined, and the characters for separating them are usually rather vague and unsatisfactory.” (Standley & Steyermark, 1946, p. 397); and “. . . revision of the genus is needed.” (Mac- bride, 1949, p. 397), showed a realization of the need for revision. In the following study, I have attempted to do my part in reduc- ing the taxonomic chaos hitherto present in Kallstroemia. The conclusions arrived at are based on the examination of herbarium specimens, and the collection and field observation of about half the species. The observations of wild populations throughout much of the range of the genus have yielded valuable information. In addition, four of the species were studied in green- house plantings, which provided information as to seed germina- tion, seedling morphology, and compatibility relationships in- volving the breeding system. At the beginning of the investigation, it was planned to obtain chromosome numbers for as many of the species as possible, and to attempt crossing experiments between different species. Un- fortunately, these goals proved to be impossible to achieve, be- ‘ Present address: Missouri Botanical Garden, St. Louis, Mo. 42 DUNCAN M. PORTER cause most of the preserved cytological material did not contain the requisite meiotic stages. In addition, there was an inadequate amount, and only sporadic flowering, of the greenhouse material. Chromosome numbers for species of the genus remain unknown, as no countable configurations were found in approximately 250 field collections of buds examined for meiosis. Although morphological analyses provided a basis for inter- preting certain natural relationships between the species, the in- formation at hand is not adequate to provide more than the barest outline of phylogenetic relationships within the genus. Future studies utilizing additional field observations, breeding experi- ments on a large scale, and information regarding chromosome numbers, while perhaps not changing the basic concepts regard- ing the species of the genus, undoubtedly will permit a more natural classification of Kallstroemia than is given in the present work. GENERIC RELATIONSHIPS The most recent synopsis of the Zygophyllaceae (Scholz, 1964) follows Engler’s (1890, 1915, 1931) placement of Kallstroemia in the tribe Tribuleae Rchb. of the subfamily Zygophylloideae along with Kelleronia Schinz, Neoluederitzia Schinz, Sisyndite E. Mey. ex Sond., and Tribulus L. Engler (1931) further divided the Tribuleae into two subtribes, the Neoluederitziinae Engl. (in- cluding Neoluederitzia and Sisyndite) and the Tribulinae (with Kallstroemia, Kelleronia, and Tribulus ). These five genera were considered to be closely related and to have arisen from a “single primitive stock” (Engler, 1915, 1931). Comparative morphology and palynology, however, indicate that whereas Kallstroemia, Kelleronia, and Tribulus form a natural group, Neoluederitzia and Sisyndite have affinities elsewhere in the family. In addition to the differences segregating the Tribulinae, stated by Engler and others (e.g., herbs versus shrubs or trees: inde- hiscent mericarps versus dehiscent capsules; lack of endosperm versus its presence; lack of staminal appendages versus their presence), pollen grain morphology has been utilized more re- cently as an additional criterion of separation. Descole, et al., (1940) were the first to distinguish the Tribuleae from the Zygophylleae on the basis of polyforate versus tricolporate pollen, THE GENUS KALLSTROEMIA 43 and Erdtman (1952) and Agababian (1964), in surveys of pollen grain morphology in the family, have indicated the homogeneity of the Tribulinae and the lack of similarity to the rest of the family. The latter author concludes (p. 44) that, “the determina- tion of the relationships of this group of genera appears to be difficult” [translation by Dr. G. K. Brizicky]. Another genus that should be included in this assemblage is Tribulopis R. Br., which some consider to be a synonym of Kallstroemia, while others include it in Tribulus. Kallstroemia, Kelleronia and Tribulopis have each, at one time or another, been considered synonyms of Tribulus, but there is good evidence supporting their position as separate genera, which constitute a natural group deserving recognition as a major subdivision of the family. Kallstroemia is composed of 17 species native to the New World: Kelleronia has about ten species in Ethiopia, the Had- hramaut, and Somaliland: Tribulopis some half-dozen species in tropical and subtropical Australia; and Tribulus a number of species native to the Old World. Like most members of the family, they are to be found mainly in arid and semiarid areas. Specimens of Tribulopis and Tribulus, as well as Kallstroemia, have been examined morphologically and anatomically. However, no material of Kelleronia has been seen. Morphological details of the latter genus have been taken from Schinz (1895), Baker (1898), Engler (1915, 1931), Chiovenda (1916, 1917, 1929), Erdtman (1952), and Agababian (1964). These four genera differ from other Zygophyllaceae in that they are mostly prostrate to ascending annual herbs, with opposite, even-pinnate leaves and inequilateral, ovate (rarely linear) leaf- lets. They have ten stamens with unappendaged filaments in two unequal series, and each filament of the outer whorl is adnate at the base to the basal portion of the petal opposite. Nectariferous tissue is present between the stamens and perianth, pollen is poly- forate, and they all have indehiscent mericarps. Vegetatively, the members of this alliance are rather similar, differing mainly in details of flowers and fruits. The five sepals are herbaceous, more or less ovate, concave, pubescent, and scarious-margined in all, deciduous in Kelleronia, Tribulopis, and Tribulus, being persistent in all species of Kallstroemia except K. californica. The five petals are free, white 44 DUNCAN M. PORTER to orange, obovate to truncate, as long as to longer than the sepals, prominantly veined, and hemispherically spreading. They are marcescent only in Kallstroemia. All four genera have five bilobed, nectariferous glands between each of the inner whorl of stamens and the sepals. These glands project downward and outward between the adjacent petals into the concave sepal base. In addition, Tribulopis and Tribulus have a second whorl of nectaries between stamens and Ovary opposite the outer whorl of stamens. It is unknown whether Kelleronia has this second set of nectaries, but they are absent from Kallstroemia. In Tribulus, the interior nectaries are triangular and free [T. alatus Del., T. macropterus Boiss., T. terrestris L. (Schweickerdt, 1937) ], or connate into a five-lobed urceolate ring surrounding the base of the ovary [T. cristatus Presl, T. excrucians Wawra, T. pterocarpus Ehrenb., T. pterophorus Presl, T. zeyheri Sond. (Schweickerdt, 1937); T. cistoides L. (Brown, 1938)]. They are bilobed and connate at the base in Tribulopis solandri R. Br. The ovary is five-carpellate in the four genera and is five-lobed and five-loculed in Kelleronia, Tribulopis, and Tribulus. In Kallstroemia it is ten-lobed and ten-loculed. Locule number is mirrored by the style and stigma, both being respectively five- ridged and five-lobed in Kelleronia, Tribulopis, and Tribulus, and ten-ridged and ten-lobed in Kallstroemia. There is a single ovule per locule in Kallstroemia and Tri- bulopis, while Kelleronia has two or more, and Tribulus has two to five, arranged in two vertical rows on the placentae. In the two latter genera, each locule becomes two- to five-compart- mented through the formation of transverse septae between the ovules. Therefore, in all four genera the ovules originally are pendulous, but ontogenetically they become horizontally arranged one above the other in Kelleronia and Tribulus. Consequently, Kallstroemia forms ten one-seeded mericarps, Tribulopis five one-seeded mericarps, and Kelleronia and Tribulus five two- to five-seeded mericarps in which the seeds are separated by trans- verse partitions. In Kelleronia and Tribulus the seeds are de- pressed and nearly horizontal, while those of Kallstroemia and Tribulopis are pendulous and obovoid. The number of seeds formed has been used in the separation of Tribulopis from Tribulus, but abortive ovules, resulting in reduced seed formation, are present in species of both these genera and in Kallstroemia, and probably result from inadequate pollination. THE GENUS KALLSTROEMIA 45 When the mericarps separate in Kallstroemia, they leave a persistent, styliferous axis that is topped by the persistent style, which forms a beak on the fruit. In Tribulus this axis is absent, and the style does not persist. It does persist to form a beak on the fruit of Tribulopis, but whether it does so following separation of the mericarps is unknown. Likewise, the situation in Kelleronia is unknown. Virtually nothing is known of the reproductive biology of Kelleronia and Tribulopis, but there are some basic differences between Kallstroemia and Tribulus. In Kallstroemia individual flowers open for only a part of one day. Pollen and the stigma mature simultaneously. The petals are marcescent and fold con- volutely together around the style following anthesis, appressing the anthers to the stigma and effecting self-pollination in all species but K. perennans. In Tribulus, flowers usually last about two days. Tribulus cistoides is protandrous (Robertson & Good- ing, 1963), with pollen shed the first day and the stigma receptive the second, while T. terrestris is protogynous (Goldsmith & Hafenrichter, 1932), with the stigma receptive the first day and pollen shed the second. Self-pollination may take place, and it occurs most frequently by the stamens curving upward and appressing their anthers to the stigma unaided by the petals. It is probable also that insects aid in some selfing. Certain differences in seed germination are found between Kallstroemia and Tribulus. In the former, germination is epigeal, the entire mericarp being carried upward by the expanding cotyledons. In Tribulus the cotyledons force their way upward to above ground level, but the mericarp remains in the ground. Usually only one seed germinates, but more than one may do so in some cases (Johnson, 1936). Cotyledons in Kallstroemia are bright green, simple, entire, concave on the abaxial surface, and have three well-marked palmate veins. They are ovate in outline and pubescent. Those of T. cistoides and T. terrestris differ in being rectangular, shiny-green, slightly tinged with yellow, parallel veined and glabrous. It can be seen from the above discussion that evidence from comparative morphology supports the recognition of four genera in this alliance. However, evidence for the elucidation of phylo- genetic relationships is lacking. More information is needed re- garding the morphology of Kelleronia, and cytological and genetical data are needed before one can knowingly discuss the 46 DUNCAN M. PORTER natural relationships of Kallstroemia, Kelleronia, Tribulopis, and Tribulus. MORPHOLOGY This section contains a general review of vegetative, floral, fruit, and seed morphology in Kallstroemia. A more detailed comparison of morphological differences between species will be found in the section titled morphological characters and _ tax- onomic criteria. VEGETATIVE MORPHOLOGY Habit. The diffusely branching herbaceous to suffrutescent stems of Kallstroemia spread radially from a stout, annual ( peren- nial in K. boliviana and K. perennans and perhaps occasionally so in K. hintonii and K. rosei) root and branch primarily from the basal nodes. In most species, stems are prostrate to decumbent in mature plants, but in K. grandiflora, K. parviflora, and K. peren- nans they may be ascending. Stems of seedlings and young in- dividuals of most species also are upright at first, but they soon fall over from their own weight and become prostrate or de- cumbent. Occasional individuals of K. grandiflora growing under exceptionally favorable conditions (e.g., along roadsides and in low places where rainwater has collected) may reach a height of one meter and a diameter of several meters. Size ranges from these large globose individuals of K. grandiflora, which may cover 16 square meters or more (Cannon, 1911), down to prostrate plants of K. curta and K. hirsutissima with a diameter of one to two feet. Roots. The root system consists of a thick, fibrous, deeply penetrating, conical tap root with a relatively stout crown, that may reach a length of several decimeters. The slender, filamentous lateral roots are mainly parallel and close to the soil surface. In the Sonoran Desert near Tucson, Arizona, Cannon (1911) found that roots of Kallstroemia grandiflora may penetrate as deeply into the ground as those of some perennials in the same area, with the tap root reaching a length of 22 centimeters, and the longest lateral root being over 21 centimeters long. This deeply penetrat- ing root system enables Kallstroemia to resume growth following THE GENUS KALLSTROEMIA 47 the normal growing season if an unseasonal rain should occur before the plant succumbs during the dry season. Stems. Stem growth is sympodial, the apical meristem changing from a vegetative to a floral meristem at each successive node. Therefore, a flower terminates the stem, further growth taking place from a vegetative bud in the axil of one of the pair of leaves at the last node. This new stem axis crowds the terminal flower of the preceding axis aside, so that the stem has a charac- teristic zig-zag appearance with seemingly axillary flowers on alternate sides at the usually more or less swollen nodes. Branch- ing occurs when the axillary bud of the opposite leaf grows out as well. This type of growth is characteristic of the Zygophyllaceae (Engler, 1890). When fresh, the stems are terete, somewhat succulent, flexible, fibrous, and tough. Upon drying, they shrink in diameter and become brittle and striate, the striations being outward mani- festations of a ring of cortical fibers. They are green, yellow- green, or reddish, drying to yellow. Like the foliage, the stems usually are densely covered with un- branched, white, gray, or yellow nonglandular trichomes. These are unicellular outgrowths of epidermal cells which may be bulbously swollen basally. They are especially prevalent at the nodes. Tri- chomes are appressed toward the stem apex and usually also spreading in all species except Kallstroemia peninsularis and a few individuals of K. pubescens from Peru, where they are retrorse. There is a correlation between amount, but not type, of pubes- cence and various climatic and edaphic factors. The specimens from drier situations are the most pubescent, while at the other extreme individuals growing under mesophytic conditions are almost glabrous. Also, specimens from alkaline soils are much more pubescent than the average. Stipules. A pair of free stipules is found on the stem at the base of the petiole. They are foliaceous, ciliate, persistent, narrowly to broadly falcate, acuminate, erect or spreading from the stem, and shorter than the petioles. The pubescence is the same as that on the stems. Leaves. Vernation is imbricate, and the leaves are opposite, one of each pair alternately smaller than the other or sometimes abortive. They are slightly succulent and abruptly even-pinnate, with the petioles usually shorter than the leaflets. Seedling leaves 48 DUNCAN M. PORTER are less divided than those of the mature plant and grade grad- ually into them. Both petiole and rachis have the same type of pubescence as the stem, and the rachis is terminated by a folia- ceous, subulate, pubescent, and apiculate mucro about one mille- meter long. Leaflets vary in number from two to ten pairs. They are usually somewhat unequal in size, those on one side of the rachis being slightly smaller than the other. The basal pair are markedly un- equal, and the terminal pair more falcate and pointed forward than the lower pairs. The leaflets are opposite, basally oblique to inequilateral, entire, acute to obtuse, mucronate, apiculate, pube- scent to glabrate, ciliate, and their margins may be flat or inrolled. Venation is reticulate. Pubescence varies from heavy (especially on younger leaflets ) to almost glabrate. Trichomes are similar to those on the stem. They are appressed toward the leaf apex and are found on both abaxial and adaxial surfaces of the blade and along its margins, being more numerous on the abaxial surface. Marginal trichomes may be so profuse as to give leaflets a whitish outline. Likewise, the petiole and rachis usually appear whitish because of numerous trichomes. The leaves show marked nyctotropic movements, the leaflets rising soon after dark and adpressing their adaxial surfaces to- gether. They return to their normal horizontal position before dawn. This movement is also readily observable within a short time after the plant is pulled from the ground. Nyctotropic move- ments have been observed to occur in all species of Kallstroemia grown in the greenhouse (K. grandiflora, K. maxima, K. pubes- cens, and K. rosei), and also in Tribulus cistoides and T. ter- restris. Under very hot and dry conditions, the leaves will fold up during the day. FLorRAL MorPHOLOGY Peduncles. The peduncles are pseudo-axillary, shorter to longer than the leaves, more or less thickened distally (becoming more so in fruit), and have the same type of pubescence as the stems and leaves. They are reflexed in bud, and erect during anthesis. Following anthesis, they usually elongate and recurve under the leaves, becoming curved, straight, or sharply bent at the base and straight above. Flowers. Flowers are solitary, pentamerous (occasionally hex- THE GENUS KALLSTROEMIA 49 amerous in Kallstroemia tribuloides), polypetalous, syncarpous, perfect, regular, and hypogynous. They appear to be alternate, but through sympodial branching of the stem they are borne terminally. Because of this seemingly alternate arrangement, the genus has been described as having a cincinnus as an inflores- cence, but this is not the case. The flowers occasionally have been described as being tetramerous, but specimens of this type have not been seen. Calyx. The five sepals are imbricate in bud. They are concave, free, lanceolate to broadly ovate in flower, foliaceous, pubescent, acute, apiculate, scarious margined, and inserted at the base of the receptacle. Trichomes may be the same or different from the type on the vegetative parts. They are not found on the scarious margins, but only on the green central portion of the abaxial sur- face, and occasionally on the adaxial surface. However, sepal margins usually appear ciliate, because the scarious margins nearly always fold involutely inward following anthesis, whether the remainder of the sepal does so or not. After anthesis the sepals may appear subulate or linear-lanceolate due to the involutely inward folding of their margins. They are persistent in all species except Kallstroemia californica. Corolla. The five petals are convolute in bud. They are free, alternate with the sepals, elliptical to broadly obovate, rounded or truncate, and irregularly notched to entire at the apex, glabrous, as long or usually longer than the sepals, fugaceous, and usually marcescent. They have prominent veins, spread hemispherically, and are inserted at the base of a fleshy, obscurely ten-lobed disc. At the base, each petal is adnate to the base of the filament of the stamen in the outer whorl opposite it. Petal color varies from white through yellow to bright orange, and also may be basally green to red, the base being darker than the remainder of the tal. Aedes The androecium is obdiplostemonous, there being two whorls of five stamens each. Filaments are inserted in the disc; they usually are filiform to subulate, but are winged at the base in Kallstroemia hintonii. Those of the two whorls are of different lengths, the ones opposite the petals being longer than the inner whorl, but shorter than the petals. Filaments are the same color as the base of the petal, varying from green to red. They are generally long enough to reach the top of the style, but in K. perennans they are only about two-thirds the length of the 50 DUNCAN M. PORTER style. The connectives often contain druses that are presumably composed of calcium oxylate. Between the base of each filament of the inner whorl and the opposite sepal is a small, ovoid, bilobed nectary. It projects downward and outward between the bases of the adjacent petals into the concave sepal base. The anthers are globose to ovoid or occasionally linear, yellow to red, bilobed, bilocular, tetrasporangiate, sub-basifixed to versatile, introrse, and longitudinally dehiscent. Those of the inner whorl occasionally are small and sterile. The pollen grains are spherical, yellow to red, and have a polyforate exine. They are shed singly. Gynoecium. The superior, sessile, ten-lobed, ten-loculed, glo- bose to ovoid or occasionally conical ovary is glabrous to sparsely or densely pubescent with straight to curved, white or gray, uni- cellular trichomes. Placentation is axile, and the ovules are one per locule, pendulous, and anatropous, with a superior micro- pyle. Sometimes one or more is abortive, especially in individuals which have been self-pollinated. The gynoecium has been described as five-carpellate, with two ovules per carpel which spuriously are divided in ontogeny by a vertical septum, thus only being secondarily ten-loculed with a single ovule per locule (Wight & Arnott, 1834; Torrey & Gray, 1838). However, ten locules are present throughout the growth of the ovary, and the change to this condition is not only onto- genetical, but is an evolutionary culmination of a phylogenetical trend. The style arises from the summit of the ovary and is cylindri- cal or conical, with a more or less conical base. It varies from glabrous to variously pubescent, is more or less ten-ridged, and terminates in as many stigmatic bands as there are locules. It persists to form a beak on the mature fruit. The clavate to capitate stigma is papillose (coarsely pubescent in Kallstroemia perennans), silvery, simple and basally lobed, or with distinct ridges. In K. peninsularis the stigmatic surfaces extend downward almost to the base of the style, but in all other species the stigma is terminal. Fruir AND SEED MORPHOLOGY Fruit. The fruit is a ten-lobed, glabrous or variously pubescent, ovoid or occasionally conical to pyramidal capsule which, upon THE GENUS KALLSTROEMIA 51 maturation, septicidally divides and separates into ten unilocular, one-seeded mericarps. However, there may be fewer than ten through abortion of some ovules. Both the beak (the persistent style) and the styliferous axis persist on the peduncle following this separation. Mature mericarps are hard and nut-like, obliquely triangular, broadly wedge-shaped, and vary from whitish to black. The glossy, variously pitted lateral faces slope into a thin straight, curved, or angled adaxial edge. The abaxial surface is rounded and thicker, may be slightly keeled or cross-ridged, and usually bears a series of rounded to elongate tubercles. This surface varies from thickly pubescent to glabrous. Seed. The oblong-ovoid seed is obliquely pendulous from the apex of the central angle of the mericarp and lacks endosperm. The testa is smooth, white, and membranaceous. It completely surrounds the embryo at maturity and is free from the mericarp wall. The embryo is straight, with ovoid, foliaceous cotyledons, a superior, conical radicle, and a rudimentary epicotyl. The only information concerning embryology in the genus is Mauritzon’s (1934) observation in “Kallstroemia maxima” that the suspensor consists of a single row of cells. REPRODUCTIVE BIOLOGY This section discusses general aspects of flowering, pollination, and seed germination in the genus. An account of suspected inter- specific hybridization will be found in the section on interspecific relationships. FLOWERING Prior to anthesis, the peduncle in Kallstroemia is reflexed, with the developing bud lying beneath the herbage. As the flowering period is approached, it becomes erect, carrying the bud into an upright position. Following pollination, the peduncle elongates and usually once more becomes reflexed, forcing the developing fruit back below the leaves. This takes place in a single day. Pollen is fully formed by the time the bud is about one milli- meter in diameter, when the anthers are essentially still sessile 52 DUNCAN M. PORTER and before filament elongation has taken place. Meiosis in the microsporocyte is of the simultaneous type, no wall forms after the first division and the two divisions are almost simultaneous. Therefore, four free nuclei are found in the microsporocyte pro- toplast before cytokinesis takes place. This is followed in the developing pollen grains by the formation of a tetrahedral tetrad. The microsporocyte cell wall disappears late in pollen maturation, and the polyforate nature of the grains can be seen prior to the disintegration of this wall. By the time the pollen grains are fully formed, the petals still consist only of primordial bumps on the receptacle. Their princi- pal period of growth takes place after the anthers reach mature size. Both the petals and filaments accelerate their growth rate immediately prior to anthesis, exceeding the sepals only at this time. Flowers in most species usually open only in the morning, closing about midday, except in cloudy weather, when they open later or remain closed. Flowering is accomplished by the con- volute petals unfolding, spreading hemispherically, and forcing the sepals backward. Sloane (1696, 1707), Don (1831), and Macfadyen (1837) have commented on the floral fragrance of Kallstroemia maxima. How- ever, I have not detected any odor in the flowers myself. This trait is not reported for any other species of the genus. POLLINATION Species of Kallstroemia so far examined in the field or grown in the greenhouse are not self-pollinated prior to anthesis. Pollen is shed after the flower has opened, at which time the stamens are appressed to, or very near the spreading petals, and the stigma is held erectly above them. The stigma is receptive to pollen at this time. Although the stamens are differentiated into two series, the anther size is only exceptionally different in the two whorls, and all ten anthers dehisce more or less simultaneously. The genus appears to be one which is pollinated promiscuously, being visited by various Diptera and Hymenoptera for pollen, and by these and Lepidoptera for nectar. Very few reports of the types of insects visiting the flowers have been recorded. According to notations accompanying herbarium specimens, Kallstroemia THE GENUS KALLSTROEMIA 53 grandiflora is visited by “bees and wasps” in Sonora and Colima, Mexico, and K. maxima by “honeybees and small flies” in Costa Rica. In Jamaica the latter species is sought out by small butter- flies for its nectar. The only pollinators of Kallstroemia to have been positively identified are bees of the genus Perdita, usually found in the deserts of the southwestern United States and northwestern Mexico on various Compositae. Perdita pectidis has been taken from “Tribulus maximus” (Kallstroemia californica or K. parvi- flora) in New Mexico (Cockerell, 1896). P. echinocacti has been found a number of times on K. grandiflora in Arizona and Sonora (Timberlake, 1954, 1960), and P. euphorbiae is known from the same species in Sonora (Timberlake, 1960). When a honeybee lands on a flower of Kallstroemia maxima, it thrusts aside the stamens, while standing over them and the style in order to reach the nectar at the bases of the sepals. In this way pollen is transferred from the anthers to the bee, and from the bee to the stigma. The bee circles clockwise on the flower until it has sampled all the nectaries, then moves on to another flower, not uncommonly returning later to the original flower, either to repeat the previous performance or to reject the flower. The bee, therefore, may act not only as an agent in cross-pollination, but also may effect self-pollination by transferring pollen from anthers to stigma in the same flower. This is accomplished in either the initial visit or upon return of the bee to a flower previously visited. Self-pollination also takes place through the following novel method. During the flowering period the filaments slowly curve upward, moving the anthers upward and appressing them to the style and stigma just before the petals close, which further ap- presses the anthers to the stigmatic surface. The clockwise, convolute twisting of the petals around the style as they close helps insure self-pollination in the absence of insect visitors. Al- though the petals are fugaceous, they usually are marcescent also and may persist twisted around the style until the fruit is mature. Greenhouse plantings of Kallstroemia grandiflora, K. maxima, K. pubescens, and K. rosei all have exhibited this phenomenon, and they have set seed following it as well. Most of the remaining species display this behavior also, for herbarium specimens of all species but K. perennans have revealed anthers appressed to stig- mas and marcescent petals. In K. perennans the stamens are 54 DUNCAN M. PORTER only two-thirds as long as the style and do not reach the stigma, and the petals are fugaceous but not marcescent. The only other member of the Zygophyllaceae known to be self-compatible is Larrea tridentata (DC.) Cov. (Raven, 1963). SEED GERMINATION Seeds of Kallstroemia are viable for at least three years, and Ernst (1876) claimed that seeds of K. maxima, among those of other weeds, retained their viability after having lain dormant in the soil for more than 30 years. However, there is some question as to whether the seeds were acually in situ for such a time, or whether they were introduced later upon exposure of the surface during excavation of the area in Caracas, Venezuela, where his observations were made. Germination of the seeds proved difficult when mericarps were placed on moist filter paper in petri dishes and these placed in the dark at room temperature. Even if the mericarp wall was broken, germination was virtually nil. These mericarps also were more liable to fungal attack than those planted in three-inch pots in a 1:1 mixture of loam and peat-moss. Here the percentage of germination was high, regardless of whether the mericarp wall was broken or not. The percentage of germination was much lower for mericarps placed in pure sand, probably because it dried out much faster than the above mixture. Germination takes place through the abaxial surface of the mericarp, which splits vertically down the center. It is epigeal, the entire mericarp being carried up into the air by the unfolding cotyledons. Following germination, rapid elongation of the pri- mary root takes place, with the aerial parts growing more slowly. The first leaves, other than the cotyledons, have two pairs of leaf- lets, anda gradual increase in leaflet number takes place until that of the mature plant is reached. Flower buds generally begin to appear with the fifth or sixth leaf. The pattern of germination exhibited by Kallstroemia maxima, K. pubescens, and K. rosei in greenhouse plantings is that termed “intermittent” by Salisbury (1961). Here the seeds germinate at irregular intervals. Following an initial burst of germination during the second week after the mericarps had been sown and first watered, seeds of a given planting were still intermittently THE GENUS KALLSTROEMIA 55 germinating over one year later. This pattern was independent of whether or not the mericarp wall had been broken, although seed- lings from scarified mericarps did begin to sprout on the ninth day following planting, one day before those from non-scarified meri- carps. According to Salisbury, intermittency is frequently caused by diversity in the permeability of the seed coat. Whether this is true for Kallstroemia can be determined only through further experi- mentation. Another possible explanation is that growth inhibitors may be present in the seed coat or mericarp which must be leached out by rainwater or soil moisture. A water-soluble in- hibitor of germination has been found in the fruit wall of Zygo- phyllum dumosum Boiss. (Koller, 1955), and the seeds of Larrea tridentata (Runyon, 1930) and of Tribulus terrestris (Johnson, 1936) exhibit dormancy, a phenomenon frequently caused by growth inhibitors (Evenari, 1949). DISTRIBUTION AND ECOLOGY Fossils of plants purported to belong to the Zygophyllaceae have been reported a number of times in the literature. However, with the exception of a single instance, all of these fossils are of extant shrubby genera with no discernable close relationships to Kallstroemia. The exception (Martin, 1963) is a report of pollen of Kallstroemia itself from southeastern Arizona, southwestern New Mexico, and northeastern Chihuahua. All of the localities from which Kallstroemia pollen was reported were alluvial deposits of less than 10,000 years of age. Unfortunately, the only information this gives us is that the genus was present at that time in an area in which it is still to be found. SPATIAL DISTRIBUTION There are four species of Kallstroemia in North America that, with justification, can be termed primarily of the warm desert, even though three of them also occur outside the desert proper. These four species are Kallstroemia californica, K. grandiflora, K. hirsutissima, and K. perennans. The first three may at times be found growing in the same locality. 56 DUNCAN M. PORTER Of the four, Kallstroemia perennans has the most restricted distribution (Map 15). This rare perennial of the Chihuahuan Desert is known only from Brewster, Presidio, and Val Verde counties in southwestern Texas. It appears to be the only species of the genus to be confined to a single type of substratum, having been collected only on limestone soils. Rainfall occurs mainly from June to September in the Chihuahuan Desert (Shreve, 1942), and K. perennans is known to flower in May, June, and September. It is found at elevations from about 650 to 1000 meters. The most common Kallstroemia in the North American deserts is K. grandiflora (Map 14), which is found throughout the Sonoran and Chihuahuan deserts except in Baja California, Mexico. It occurs also in the mesquite-grassland formation! between these two warm deserts, as do K. californica and K. hirsutissima. Kallstroemia grandiflora ranges south of the desert proper along the west coast of Mexico from southern Sonora to the valley of the Rio Balsas and in northern Guerrero as well. In its southern ex- tension, this species is found in thorn forest and tropical deciduous forest from southern Sonora to Colima and in arid tropical scrub in Michoacan and Guerrero. This area is characterized by arid vegetation types and marked wet and dry seasons (Shelford, 1963). Kallstroemia grandiflora is a typical summer annual over most of its range. It flowers mainly from July through October, following the heavy summer rains that usually fall during this time in the Sonoran and Chihuahuan deserts (Shreve, 1942, 1951), and south along the semiarid west coast of Mexico (Shelford, 1963). Flowering may take place sporadically at other times if conditions are adequate for seed germination and plant growth. Further south, from Jalisco to Guerrero, the scanty information available indicates that growth and flowering takes place sporadi- cally from August to March, presumably following fall and winter rains, although Shelford (1963) states that most of the precipita- tion in this area falls from June to September. The species occurs from sea level to about 2000 meters and is found mainly on sandy soils, being particularly common on the sandy expanses of the Sonoran Desert. A number of specimens from the easternmost part of its range in Texas and Mexico have been collected on limestone and gypsum soils. * Except where noted, the terms used for Mexican vegetation types are those of Leopold (1950). THE GENUS KALLSTROEMIA | Kallstroemia californica (Map 10) is another primarily warm desert species. It occurs over much of the same area as K. grandi- flora, but is distributed more widely in all directions except to- ward the south. Like that species, it continues in the thorn forest southward along the Mexican west coast. However, it extends only as far south as southern Sinaloa. Unlike K. grandiflora, K. cali- fornica is found in the westernmost extension of the Sonoran Desert in Baja California, where it also ranges southward into the tropical deciduous forest of the Cape Region. It occurs in the Mojave Desert of California as well, where, similar to K. grandi- flora in the Sonoran and Chihuahuan deserts, it “may carpet the desert for miles after a rainy summer” (Munz, 1962, p. 97). Kallstroemia californica is found eastward through the mesquite- grassland formation and across the northern sections of the Chihuahuan Desert, where its distribution is rather spotty, to southern Texas and northeastern Mexico. In the northern area of its distribution and east of the desert, this species becomes more abundant in the various arid grassland formations it inhabits. It is common within the mesquite-grassland of southern Texas, and occurs less frequently in the Acacia-grassland (fide Shelford, 1963) both in Texas and the south and southwest in the Mexi- can states of Coahuila, Nuevo Leon and Tamaulipas. Throughout most of its range, K. californica grows and flowers from July through October, following the summer rains. Exceptions are in Texas, where flowering may begin in May or occasionally as early as March, and in Baja California. In the latter area, the plants behave as winter annuals, growing and flowering from August through March, following fall and winter rains. Such a growth cycle is unusual for the genus, but it is not particularly so for the area, as the Sonoran Desert in Baja California is extremely poor in summer annuals (Shreve, 1951). Like K. grandiflora, K. californ- ica is to be found mainly in sandy disturbed areas, where it occurs mainly at lower elevations, but extends from sea level to about 1600 meters. This species apparently has increased its range east- ward in recent times, concomitant with the invasion of the grass- lands by arid scrub. The fourth species of the warm desert group, Kallstroemia hirsutissima (Map 7), is distributed most commonly in the Chi- huahuan Desert, but it extends northwestward through the mes- quite-grassland formation to that portion of the Sonoran Desert PORTER DUNCAN M. Mt wena \/ a oa 2 MAN We q Ay) Agee aot irk See hs } ‘ \ ’ » ma. Map 4. New World distribu- i 1a max exclusive of Ecuador andPerti (see Mar 5). . ibution of Kallstroem Map 1. tion of Kallstroemia pubescens, THE GENUS KALLSTROEMIA 59 in southeastern Arizona that Shreve (1951) has called the Arizona Upland. As is true of K. californica, K. hirsutissima occurs to the east in the mesquite-grassland and Acacia-grassland formations of southern Texas and northeastern Mexico. However, it has not been collected often in the latter area. It is a summer annual, known to germinate, grow, and flower only from June to October, but mostly from July through September. Kallstroemia_hirsutis- sima is found from sea level to about 1700 meters, mainly at higher elevations. Perhaps, as is suggested for K. californica, it has recently spread eastward into the semiarid grasslands. There is a fifth species which ranges to some extent into the North American warm deserts, but in contrast to the others, it appears to be the only Kallstroemia that is indigenous to areas characterized by various grassland formations. Kallstroemia parvi- flora (Maps 5, 16) has been collected from Illinois south to the central Mexican states of Guanajuato, Querétaro, and Hidalgo. It occurs from California east to Mississippi and has been intro- duced into Peru as well. In Mexico, K. parviflora is almost entirely confined to the mesquite-grassland, but it has been collected sporadically in the Chihuahuan Desert also. To the northwest, it has been found occasionally in the United States in the Sonoran and Mojave deserts and beyond. The species is most common in Texas, from whence it ranges northward through New Mexico and Oklahoma to Colorado and Kansas, mainly occurring west of 96° longitude. Kallstroemia parviflora occurs sporadically to the east into Missouri and Illinois, where it has been introduced along the railroads, and it is also known from a single collection in Mississippi. In the United States this species is to be found mainly in the mesquite-grassland, and the different grasslands characterized by short-grass, mixed-grass, and tall-grass (fide Shelford, 1963). It occurs sporadically outside of these areas. Flowering is mainly from July to September throughout this vast range. Germination and growth follow the summer rains, which decrease in amplitude toward the north. However, growth and flowering may take place at other times as well if conditions of moisture and temperature are adequate. It is interesting to note that this species remains a summer annual where it has been introduced in Peru, flowering from November through April. There it has been collected in localities characterized by different communities of subtropical scrub receiving summer rainfall ( Tosi, PORTER DUNCAN M. foceet 4 i] i i i iad maxima 1 Map 2. Distribution of Kallstroem Distribution of Kallstroemia cu ornica, Map 14. Distribution of Kallstroemia grand calif. THE GENUS KALLSTROEMIA 61 1960). Kallstroemia parviflora is to be found usually in sandy disturbed areas, but in a report on the desert gypsum flora of western Texas and adjacent New Mexico, Waterfall (1946) in- dicated that this species (reported as K. brachystylis) grew well on gypsum. However, he thought that the plants observed were probably gypsum tolerant, rather than gypsophilous. There are six species of Kallstroemia that occur in Mexico in addition to three of the four species discussed above. Of the six, four are endemic to Mexico, and three of these endemics have a restricted distribution. Kallstroemia standleyi appears to have the narrowest distribution of the Mexican endemics, but further in- vestigation will undoubtedly prove it to have a wider range than is known at present. Kallstroemia standleyi has been collected only at the type locality, on sand dunes near the beach, one-half mile east of Salina Cruz, Oaxaca (Map 11). Leopold (1950) and Shel- ford (1963) characterize the vegetation of this general area as savannah, but from personal observation I would say that the coastal area in the immediate vicinity of Salina Cruz is better termed arid tropical scrub. It is possible that the presence there of a xerophytic vegetation type may be a secondary phe- nomenon due to man’s interference through cutting and grazing. This species is known to flower in July. The second Mexican endemic with a restricted distribution is Kallstroemia hintonii, known only from elevations of from 300 to 400 meters in the general region of Apatzing4n, Michoacan (Map 11). Although K. hintonii has been collected only a half- dozen times, it does not appear to be rare where it is found. Leavenworth (1940) states that it may be seen “coloring whole fields at times,” and I have found a population which stretched for about two miles along both sides of the road between Apatzingan and Aguililla, Michoacan. The vegetation of the Apatzingan area is tropical deciduous forest and arid tropical scrub. Summer rains predominate and occur from June to Septem- ber (Shelford, 1963). Kallstroemia hintonii is known to flower in August, September, and December. The southern part of the Mexican territory of Baja California Sur contains the endemic Kallstroemia peninsularis (Map 15). This species is found mainly in low sandy areas and sandy beaches in the tropical deciduous forest of the Cape Region, but it also occurs occasionally to the west and north in the Sonoran Desert. 62 DUNCAN M. PORTER : a ne 2 Wns nro get i a ioe si Distribution of Kallstroemia rosei. ae 7; st ipa “ns Kall- hirsutissima. Map 11. Distribution of Kallstroem i (tri angle) a K. hintonii. Mar 15. Distribution of re ali peninevlésie K. perennans (triangles), THE GENUS KALLSTROEMIA 63 The Cape Region of Baja California differs from the adjacent desert area in that the more copious rains usually fall during the summer months, although winter rains are not unknown (Shreve, 1937). Kallstroemia peninsularis is known to flower from August through March, following both summer and winter rains. The most widespread Kallstroemia endemic of Mexico is also the one found in the most mesophytic vegetation type. Kall- stroemia rosei (Map 3) appears originally to have been restricted to open disturbed sites in the pine-oak forest of central and north- eastern Mexico, but man has distributed it into lower and more xerophytic habitats, especially Guerrero and Michoacan. At pres- ent, it occurs from 200 to 3150 meters, mainly at higher elevations. Kallstroemia rosei ranges from the Sierra Madre Oriental in Nuevo Le6n to the Sierra de Oaxaca and Sierra Madre del Sur in central Oaxaca, and from Jalisco to Puebla in the mountains of central Mexico. It is very common also in the Rio Balsas basin and is found sporadically at lower elevations elsewhere. The pine-oak forest area of Mexico has a rainy season that generally extends from June through September (Shelford, 1963), and K. rosei usually flowers during this time, although scattered instances of flowering until March are known. The Caribbean region has three species of Kallstroemia, two of which have a very wide distribution, both occurring outside of this area. In contrast to their more temperate congeners, these more tropical species may be found flowering thoughout the year. Seed germination and growth appear to be almost wholly dependent upon the presence of adequate moisture—at least this appears to be true in their native habitats. The island of Hispaniola seems to be the original area oc- cupied by Kallstroemia curta. It has probably been introduced into Cuba and the Netherlands Antilles islands of Aruba, Bonaire, and Curagao (Map 8). This species is the most restricted of the Caribbean members of the genus. It occurs from sea level to 1300 meters but is found mainly at lower elevations. One of the most widespread species of Kallstroemia is K. maxima (Map 1). It is commonest in the islands of the Caribbean and in western Central America. This species also ranges across northern South America and northward along both coasts of Mexico to the Tropic of Cancer and beyond. In the southeastern United States it occurs as far north as South Carolina, and it has 64 DUNCAN M. PORTER (squares) in Ecuador and outh America. Map 6. 12. Distribution of Kall- troemia tribuloides. . em: AP stroemia boliviana. Mar 13. Distribution of Kalls THE GENUS KALLSTROEMIA 65 been introduced into Brenham County, Texas, where it persists. This weedy species of sandy disturbed soils has been collected at elevations ranging from sea level to about 1350 meters, but it is especially prevalent along roadsides and in cultivated areas at lower elevations. Kallstroemia maxima rarely is to be found out- side of areas that are frost-free the year around. A species that occurs sympatrically with Kallstroemia maxima over much of its range is K. pubescens ( Maps 4, 5). Although the two are found growing in the same locality occasionally, they appear to be at least partially isolated ecologically. Kallstroemia pubescens tends to be found in sandier situations at slightly higher elevations than K. maxima. It occurs from sea level to 1400 meters, being most common at lower elevations. It is commoner than K. maxima in the Lesser Antilles and is almost completely absent from the Greater Antilles. Kallstroemia pubescens is found in disturbed areas through western Central America as far north as Yucatan on the southeastern coast of Mexico, while on the west coast it reaches southern Sinaloa. It is less common through this area than K. maxima. However, K. pubescens ranges further south than the latter species, occurring in the xerophytic coastal area (fide Svenson, 1946a) of Ecuador and northern Peru. It is also known from a single locality in western Florida. This species flowers the year around, except in Ecuador and Peru, where it flowers during the rainy season from February to April. It is the only Kallstroemia known outside of the New World, having been introduced to coastal Ghana and Nigeria (Keay, 1955) and West Bengal, India (Bennet, 1965). Five species of Kallstroemia are endemic to South America. Of these, two have been found growing in the same localities, and mixed collections of herbarium specimens are sometimes found. These two species, K. tribuloides and K. tucumanensis, have the southernmost distributions in the genus (Maps 6, 13). Both of them are native to a region characterized by xerophilous scrub- lands (Cardenas, 1945; Cabrera, 1951) which stretch along the eastern base of the Andes from southern Bolivia to central Argen- tina. They have been collected at elevations from 300 to 1800 meters in this area. This arid and semiarid region is similar to those of North America where the genus is found, and summer rain predominates (Cabrera, 1951). Seed germination and plant growth take place following these rains. Kallstroemia tucuman- 66 DUNCAN M. PORTER Map 9. Distribution of Kallstroemia adscendens. Mar 16. Distribution of roemia parviflora in North America (see Map 5 for South American distribution ). THE GENUS KALLSTROEMIA 67 ensis flowers from November to April, and K. tribuloides from November to May. The former has been found farther north and south than K. tribuloides, but the latter also is known from north- eastern Brazil (Map 13) in an area dominated by deciduous scrub forest (Smith & Johnston, 1945). Kallstroemia tribuloides is thought to have been introduced to Brazil from Argentina ( Descole, et al., 1939). The Brazilian collections that I have seen were mainly from sandy places along the Rio Sao F rancisco, the largest river in the area. This species is also found in similar situations in Argentina. Another species which occurs in Bolivia is Kallstroemia bolivi- ana. It is found in the semiarid valleys of the eastern slopes of the Cordillera Oriental at elevations from about 1100 to 2800 meters (Map 12). A single Peruvian collection is known from a compa- rable area at an elevation of 1300 to 1400 meters where the vegeta- tion is subtropical spiny shrubland (Tosi, 1960). Kallstroemia boliviana flowers from October through April. The interandean region of Bolivia, where it is to be found generally, receives summer precipitation from November through April (Franze, 1927), The Peruvian Kallstroemia pennellii is known only from the type locality along the Rio Marafion above Balsas, Cajamarca, at an altitude between 700 and 900 meters ( Map 5). The vegetation of this area is tropical spiny forest (Tosi, 1960), a hot semiarid formation of northern Peru. This locality is characterized by sum- mer rains and very high temperatures. The single collection known flowered in April. The fifth, wholly South American Kallstroemia, is K. adscen- dens, an endemic of the Galapagos Islands, Ecuador (Map 9). It is known from the islands of Charles, Chatham, Duncan, Gardner, and Hood. It has been collected on beaches and lower slopes of the arid coastal zone, where the vegetation is predominantly xerophytic shrubs and subshrubs (Robinson, 1902). According to Svenson (1946a), sporadic rains occur in the islands from February to June. Flowering of K. adscendens is known to take place from April through June. Based on a broad scope of information, a certain correlation may be seen between the occurrence of Kallstroemia and regions with high summer temperatures and summer precipitation, al- though the genus is by no means restricted to such areas. Those 68 DUNCAN M. PORTER tropical species occurring in regions where rainfall and high temperatures may be found throughout the year grow and flower at any time. However, where the tropical representatives of the genus are encountered in areas with definite wet and dry seasons, they show the same periodicity in seed germination and plant growth as the temperate species found under similar circum- stances. HABITAT Species of Kallstroemia are invariably found in open, disturbed habitats. These habitats may be natural, as in desert areas, or artificial, such as those provided by man in his rapid destruction of the natural vegetation. Plants of open natural habitats in deserts and sparsely occupied sand dunes, beaches, etc., have the greatest facility for spreading into and colonizing artificially created hab- itats (Salisbury, 1942, 1961). Open desert land, sand dunes, and beaches were undoubtedly the prime habitats of Kallstroemia prior to the invasion of the New World by European man. Since then, and perhaps to a limited extent even before, the resulting deterioration of the natural vegetative cover and the concom- itant increase of disturbed habitats have provided numerous new areas into which species of Kallstroemia could migrate. At present, the most common situations where species of the genus are to be found as weeds are roadsides and cultivated areas. Clements (1920) has stated that the presence of K. californica (listed as K. brachystylis), K. grandiflora, K. hirsutissima, and K. parviflora is an indication of overgrazing in the arid grasslands of the south- western United States. Kallstroemia parviflora became a trouble- some weed in southern Kansas soon after the beginning of cultiva- tion in that area (Carleton, 1892: Holzinger, 1892). DispersAL MECHANISMS Species of the genus inhabiting desert areas probably are dis- persed through the action of rain wash. However, sea water dispersal probably does not take place in Kallstroemia. I have observed that the mericarps of two Caribbean species, K. maxima and K. pubescens, like those of Tribulus cistoides (Guppy, 1906), will not float in sea water. Unlike most of Tribulus, the mericarps of Kallstroemia lack appendages that would allow them to cling THE GENUS KALLSTROEMIA 69 to the outer surface of an animal, with the exception of those with rough tubercles as in K. californica and K. standleyi, and those with hispid trichomes as in K. perennans. However, animal dispersal may take place because of the mucilaginous sheath secreted by the mericarps when they are wet. This sheath could allow them to adhere to an animal and in drying bind them temporarily to skin, fur, or feathers. Mucilage produced by the wetted mericarps may not only increase chances of dispersal, but it could act to anchor the mericarps to the soil, providing a de- cided advantage for the small disseminules of species growing in open situations. Dispersal of disseminules through formation of an adherent mucilage is well documented (e.g., Salisbury, 1961). The hard pericarp of the mericarps also may allow them to be eaten and passed through the digestive tract of an animal un- harmed. This ingestion could act to break seed dormancy as well. There is no concrete evidence for internal transport by animals, but it is known that in Arizona Kallstroemia grandiflora seeds are fed upon by quail (Griner, 1940) and the herbage is eaten by herbivores (McGinnies, 1922). In Peru, K. parviflora is browsed by livestock (Macbride, 1949). Similarly, K. tribuloides and K. tucumanensis are browsed in Argentina (Ruiz Leal, 1947, 1951). Today the animal most important in dispersal of the genus is man. The southward spread of Kallstroemia tucumanensis has been facilitated through man’s action, probably by the mericarps being imbedded in mud attached to vehicles (Ruiz Leal, 1951). Undoubtedly, man has been instrumental in carrying K. maxima to Texas, K. parviflora to Peru, and K. pubescens to West Africa and India. In the latter case, K. pubescens was discovered along a railroad right-of-way (Bennet, 1965). Railroads appear to have played a leading role in the spread of K. parviflora north and east from its presumed original area of occupation in North America. Early collections show this species to have advanced mainly along railroad rights-of-way. But now, like most other species in the genus, it is primarily dispersed by the automobile. This is so often the case that species of Kallstroemia are frequently to be found in disturbed areas along roads and highways. Vegetative dispersal probably does not take place. There is no evidence for vegetative reproduction in the genus. This is not unexpected in a group of plants that mostly are ephemeral an- nuals. 70 DUNCAN M. PORTER DIsTRIBUTION AND SELF-COMPATIBILITY The prevelance of self-compatibility in desert annuals and particularly in weedy plants is well documented (cf., Stebbins, 1950; Baker, 1955; Salisbury, 1961). From observations on the reproductive biology of Kallstroemia, it can be inferred that all species of the genus, with the probable exception of K. perennans, are self-compatible. There are three situations under which self- compatibility proves to be advantageous in the survival and spread of a species: (1) Individuals may resort to self-pollination if conditions are unfavorable for outcrossing, as in the absence of pollinators (Stebbins, 1950 )—this situation also could arise where individuals are so widely spaced that the frequency of outcrossing is restricted (Fryxell, 1957); (2) In cases of long distance dis- persal, only a single disseminule is necessary for the establishment of a new colony if the species is self-compatible (Baker, 1955); (3) In the colonization of temporary habitats, such as those in- habited by weeds, there is a premium placed on species that can rapidly build up populations of individuals that are as well adapted as their parents to these temporary situations (Stebbins, 1950). This can be accomplished most successfully by relatively homozygous individuals belonging to self-fertilizing lines (Steb- bins, 1957). The above processes undoubtedly have occurred in the past and are presently ocurring in Kallstroemia. Absence of polli- nators and wide separation of individuals (ie., as weeds along roadsides ) are surmounted through selfing. Isolated individuals invariably set seed in the field. The presence of self-compatibility has probably been a factor in the introduction and persistence of K. maxima in Texas, K. parviflora in Peru, K. pubescens in West Africa and India, and K. tribuloides in northeastern Brazil. In addition, it has aided in the rapid spread of most species to disturbed environments. Direct evidence for rapid build-up through preadaptation is lacking because nothing is known con- cerning the genetics of the genus. Self-compatibility permits self-fertilization, but it does not in- sure it. This insurance is provided in Kallstroemia by the stamen and petal movements which act to appress pollen to the receptive stigma. However, self-fertilization is facultative, and outcrossing probably predominates under many circumstances. Stamen and petal movement occur whether outcrossing has taken place or not. THE GENUS KALLSTROEMIA 71 It would be interesting to know whether there is any differential pollen tube growth between selfed and crossed pollen. Biotic RELATIONSHIPS Occasional individuals of Kallstroemia hirsutissima, K. maxima, . parviflora, and K. tucumanensis have been encountered in which the nodes or fruits had been attacked by insect larvae. Some Central American populations of K. maxima examined in the field were highly infested with these larvae to the extent that practically every fruit had been attacked. A small black aphid is commonly found on the herbage of many species of Kallstroemia. North American specimens of the introduced Tribulus terrestris commonly are covered with a similar aphid. Two insects that have been introduced into the western United States for the biological control of Tribulus terrestris may prove harmful to indigenous species of Kallstroemia, and perhaps to Larrea tridentata, also. It has been reported by Andres and Angalet (1963) that adults of these insects will feed on the leaves and stems of Kallstroemia californica, K. grandiflora, Larrea tridentata, and Zygophyllum fabago (an introduced weed in California), as well as Tribulus terrestris. Microlarinus lareynii (Jacquelin du Val), a seed weevil, will oviposit on fruits of both K. californica and K. grandiflora, but larvae develop to maturity only in the latter. Microlarinus lypriformis (Wollaston), a stem weevil, will not oviposit on Kallstroemia. A discussion of insect pollen vectors of Kallstroemia is found above in the section on reproductive biology. At least two species of Kallstroemia are parasitized by other plants. I have seen specimens of K. grandiflora from Arizona and Sonora, Mexico, and K. maxima from Puerto Rico and Yucatan, Mexico, that were host to Cuscuta umbellata HBK. Tribulus terrestris is commonly parasitized by this species, also. Yuncker (1965) reports C. erosa Yunck., a species of southern Arizona and northern Mexico, on an unidentified species of Kallstroemia. MORPHOLOGICAL CHARACTERS AND TAXONOMIC CRITERIA The only previous work of a revisional nature on the genus is that of Rydberg (in Vail & Rydberg, 1910). In this and subse- f2 DUNCAN M. PORTER quent publications, the main criteria used in species delimitation were flower size, sepal shape, type and distribution of ovary and fruit pubescence, shape and length of the persistent style, and amount and type of pubescence on the herbage. These characters were not consistently given the same importance in every Case. In the present study, it has been found that such additional characters as spatial relationship of the persistent sepals to the mature fruit, mericarp morphology, stigma shape, and leaf shape are im- portant also. The criteria utilized by Rydberg were found in the main to be useful, albeit not always in the same context that he had used them. The fallacies of relying on single characters or those of a purely vegetative nature in classification have been clearly indicated (Rollins, 1952, 1957). Accordingly, the species are delimited herein by constellations of character combinations (fide Rollins, 1957). As may be seen in the following discussion, these character combinations provide the basis for a certain number of inferences concerning natural relationships in the genus. There is a great deal of variation in the absolute size of the vegetative structures in plants of Kallstroemia. Size and the amount of pubescence on these parts appear to depend mainly upon the conditions under which the plants have developed. A high degree of variation in the vegetative parts is encountered fre- quently in plants of arid and semiarid regions. This in turn can be attributed to concomitant variation in climatic and edaphic conditions (e.g., Schweickerdt, 1937). There is also a certain amount of variation in flower and fruit size in species of Kall- stroemia that appears to be somewhat influenced by conditions during the growth of the plant. Robust individuals have longer internodes, stems, and peduncles, and larger leaves, leaflets, flow- ers, and fruits, in comparison with depauperate individuals which grew under conditions of inadequate moisture, excessive disturb- ance, or highly alkaline soils. The latter are much smaller in all aspects, both vegetative and floral. However, the quantitative dif- ferences traceable to the influences of local environmental factors do not transcend the qualitative differences that serve to distin- guish the species. VEGETATIVE CHARACTERS Stems. The stems of most species of Kallstroemia are prostrate to decumbent in mature individuals. Exceptions are the ascending THE GENUS KALLSTROEMIA 73 stems of occasional plants of K. grandiflora and K. parviflora and most individuals of K. perennans. In K. curta and K. hirsutissima the stems are prostrate only. The taxonomic value of the stem habit itself is limited, but it can be utilized in concert with other morphological traits. Lengths of the stems and internodes at times have been used to help delimit species, but these characters, like most others of a quantitative nature, may be very variable within a species. Presence, absence, or amount of stem striation are frequently given in taxonomic descriptions for each species, but striate stems are found throughout the genus. Striations are due to a ring of cortical fibers and are not seen in the somewhat succulent stems of living plants. They become evident only after the stem has dried and shrunk. The most useful taxonomic character of the stems is found in their pubescence. The trichomes are antrorse (directed apically ) in all species but Kallstroemia peninsularis and a few specimens of K. pubescens from Peru, where they are retrorse. In most species, the stems are hirsute and sericeous, but exceptions are to be found in K. californica (hirsute and strigose), K. penin- sularis (hirsute and hirtellous), K. perennans (hispid and strigose), K. pennellii (strigose), and K. tribuloides (sericeous ). The same type pubescence as that of the stem is to be found on stipules, peduncles, petioles, and rachises. Stipules. There is little difference in the stipules from species to species. Whether they are persistent or deciduous in mature individuals has been used in some taxonomic descriptions, but the stipules are absent only if they have been lost in the process of collecting, drying, and mounting the herbarium specimens. Leaves. There are two distinct shapes of leaves in the genus. In one type, the terminal pair of leaflets is the largest, conse- quently the leaf shape is obovate. This leaf type is found in Kall- stroemia boliviana (Fig. 10b), K. curta (Fig. 6b), K. hirsutissima (Fig. 5b), K. maxima (Fig. 1b), K. pubescens (Fig. 3b), K. rosei (Fig. 2b), and K. tucumanensis ( Fig. 4b). In the second type, one of the lower pairs of leaflets is the largest, and leaf shape is ellipti- cal. This type is found in K. adscendens (Fig. 7b), K. californica (Fig. 8b), K. grandiflora (Fig. 13b), K. hintonii (Fig. 17b), K. parviflora (Fig. 16b), K. peninsularis (Fig. 14b), K. pennellii (Fig. 12b), K. perennans (Fig. 15b), K. standleyi (Fig. 9b), and K. tribuloides (Fig. 11b). The species with obovate leaves have fewer leaflets, on the average, than the species with elliptical 74 DUNCAN M. PORTER leaves. This difference in leaf shape does not indicate the presence of two basic groups of related species in the genus, however. Sev- eral closely related species of Kallstroemia differ in leaf shape, and K. californica usually has elliptical leaves, but individuals occasionally are partially or wholly obovate-leaved. Leaf size may vary more within some species following changed environmental conditions than it does between the species. Also, there is no correlation between flower size and leaf shape or leaflet number. Leaflet number differs somewhat from species to species, but in several instances (i.e., Kallstroemia californica, K. grandiflora, K. maxima, K. parviflora, and K. tribuloides) there may be a sizeable difference in number from individual to individual within a species. Leaflet number in de- pauperate specimens is lower than usual. There is insufficient difference in leaf or leaflet size from species to species for either to play a major role in the discrimination of taxa within the genus. Leaflet pubescence in most species is appressed-hirsute on both surfaces of the blade. The abaxial surface is usually more pubes- cent than the adaxial surface. The main vein and margins are usually sericeous. Exceptions are Kallstroemia boliviana, K. pen- nellii, and K. standleyi, in which the pubescence of the leaflets is entirely sericeous, and K. hintonii, where it is wholly appressed- hirsute. FLORAL CHARACTERS Flowers. There are substantial differences in flower size and color between different species of the genus. Flower size and color are relatively stable characters in some species, while in other species they may be quite variable. Depending upon the situation, they may be of more or less diagnostic value. There are certain correlations between flower color and size in that those species with small flowers, less than one centimeter in diameter (Kallstroemia adscendens, K. californica, K. curta, and K. hirsutissima) always have yellow petals. But petal color in the larger-flowered species varies from white through yellow to bright orange with the basal portion varying from green to red. In these latter species the petal base is usually somewhat darker than the distal portion. In some populations of K. grandiflora, K. hintonii, and K. maxima the base is a bright red. Calyx. Following anthesis, there are three basic configurations THE GENUS KALLSTROEMIA 75 Fic. 1. Kallstroemia maxima: a, leaf, b, fruit, of Porter 1035. Fic. 2. Istroemia rosei: a, leaf, b, fruit, “of Porter 1375. Fic. 3. Kallstroemia pube- a, leaf, b, fruit, of Stewart 1166. Fic. 6. Kallstroemia curta: a, leaf of Leonard & Leonard 13322; b, fruit of Ekman — Fic. 7. Kallstroemia adscendens: a, leaf, b, fruit, of Snodgrass & Heller 7. 76 DUNCAN M. PORTER of the sepals which are very useful taxonomically. They may clasp the base of the mature fruit, with only the scarious margins folding involutely under, if at all, as in Kallstroemia boliviana (Fig. 10a), K. hintonii (Fig. 17a), K. hirsutissima (Fig. 5a), K. maxima (Fig. la), K. pennellii (Fig. 12a), and K. tribuloides (Fig. lla). They may spread from the base of the mature fruit, occasion- ally curving upward, with the margins sharply folding involutely upon one another and making the sepals appear linear or linear- lanceolate to the naked eye, as in K. adscendens (Fig. 7a), K. californica (sepals usually deciduous; Fig. 8a), K. curta ( Fig. 6a), K. pubescens (Fig. 3a), K. rosei (Fig. 2a), K. standleyi (Fig. 9a), and K. tucumanensis (Fig. 4a). Instead of spreading, the sepals may curve upward around the mature fruit, shriveling and turn- ing brown, as in K. grandiflora (Fig. 13a), K. parviflora (Fig. 16a), K. peninsularis (Fig. 14a), or K. perennans (Fig. 15a). A further character is the type of pubescence present on the sepals (see above figures). The indument may be _ hirsute (Kallstroemia curta, K. hintonii, K. hirsutissima, and K. maxima , hirsute and strigose (K. adscendens, K. boliviana, K. rosei, and K. tribuloides), hispid and strigose (K. grandiflora, K. parviflora, and K. perennans), hispid and hirtellous (K. peninsularis), hispidulous (K. pubescens and K. tucumanensis), sericeous (K. pennellii and K. standleyi), or strigose to hirsutulous and strigillose (K. califor- nica). There is an evident correlation between the presence of hispid and strigose pubescence and the upwardly turned sepals which ultimately shrivel and turn brown Corolla. See the discussion above under flowers. Androecium. The filaments are filiform or subulate in all species except Kallstroemia hintonii, where they are winged at the base. They are sufficiently long to extend the anthers upward and appress them to the stigma except in K. perennans, where the filaments reach only two-thirds up the length of the style. Fila- ment color is correlated with the color of the petal base. Because the colors of the two are always the same, they are assumed to be genetically linked. In a given flower, anther and pollen color are the same. How- ever, the color may differ both between and within species. The color range is from yellow to red. In Kallstroemia adscendens, K. californica, K. curta, K. hirsutissima, K. parviflora, K. peninsularis, K. standleyi, and K. tucumanensis the color is yellow; in K. boliv- THE GENUS KALLSTROEMIA Tt iana, K. hintonii, K. perennans, and K. tribuloides it is orange or red. In the remaining species, populations of individuals may have anthers and pollen that are some shade of either yellow, orange, or red. Kallstroemia maxima and K. pubescens may be either yellow or red; K. grandiflora and K. rosei usually are orange or red, rarely yellow. The anther and pollen color of K. pennellii is unknown. Yellow-flowered individuals usually have yellow anthers and pollen as well, but this is not invariably the case (e.g., as in K. hintonii). There is a correlation and presumably genetic linkage between a red petal base and red anthers and pollen in K. grandiflora, K. hintonii, and K. maxima. These color differences usually are reliable criteria only in fresh material, because of fading and color changes which accompany the drying of specimens. Anthers in Kallstroemia standleyi and K. tribuloides are reg- ularly linear-oblong; otherwise they are ovoid or globose through- out the remainder of the genus. However, occasional specimens of K. grandiflora, K. maxima, K. parviflora, K. rosei, and K. tribuloides have been seen in which one whorl of stamens has linear anthers. Occasionally, one whorl of stamens has abortive anthers. Gynoecium. The ovary is ovoid or globose in most species of Kallstroemia, but in K. boliviana, K. rosei, and K. tribuloides it is conical, and pyramidal in K. pubescens. It is almost always pubescent, being glabrous only in K. hintonii, K. maxima, and K. tribuloides, but it is occasionally strigose in K. maxima. As with all other floral structures, ovary size varies with overall flower size, being correspondingly large or small. Style length, like ovary size, differs with the flower size, smaller- flowered species having shorter styles. There may be a certain amount of variation of style length within a species, but in Kall- stroemia grandiflora, K. hintonii, K. maxima, K. parviflora, K. peninsularis, K. pennellii, K. perennans, K. rosei, K. standleyi, and K. tribuloides it is nearly always longer than the ovary. In the other species, it is equal to or shorter than the ovary. Style shape in the genus is mostly cylindrical above and conical below, but K. adscendens, K. boliviana, K. californica, K. curta, K. hirsutissi- ma, K. pubescens (rarely cylindrical above), K. rosei, and K. tucumanensis all have more or less stout conical styles. Therefore, one can see a definite correlation between style length and 78 DUNCAN M. PORTER eaf, b stroemia t eaf, b, fruit, of Schreiter s. n. Fic. 12. Kallstroemia peut ii: a, leaf, b, fruit, of Palak 15185 we Fic. 13. Kallstroemia ee i a, leaf, b, fruit, of Gentry 1 THE GENUS KALLSTROEMIA 79 shape, stout, conical styles generally being shorter than the ovary. There are differences in the amount, type, and distribution of stylar pubescence. Most species are glabrous to strigose in this character, but the style is hirsute in K. perennans. In K. hirsutis- sima and K. rosei it is surrounded at the base by a ring of hirsute pubescence, a feature that is especially pronounced in the latter species. There appear to be three fundamental stigma types in Kall- stroemia. The stigma may be capitate and obscurely ten-lobed, as in K. maxima (Fig. la), K. pubescens (Fig. 3a), and K. rosei (Fig. 2a). The stigma may be oblong and ten-ridged, as in K. boliviana (Fig. 10a), K. parviflora (Fig. 16a), K. pennellii (Fig. 12a), K. perennans (Fig. 15a), K. standleyi (Fig. 9a), K. tribuloides (Fig. lla), or K. tucumanensis (Fig. 4a). It may be clavate and ten-ridged, as in K. adscendens (Fig. 7a), K. californica ( Fig. 8a), K. curta (Fig. 6a), K. grandiflora (Fig. 13a), K. hintonii (Fig. 17a), K. hirsutissima (Fig. 5a), and K. peninsularis (Fig. 14a). There are no general correlations between stigma type and flower size or style length. The stigmatic surface is papillose in all species but Kallstroe- mia perennans, where it is coarsely canescent (Fig. 15a). It extends downward almost to the stylar base in K. peninsularis (Fig. 14a) but is terminal in all other species. Fruir CHARACTERS Peduncles. The length of the peduncle in fruit is of some tax- onomic significance. In Kallstroemia californica, K. curta, K. hirsutissima, K. perennans, K. pubescens, K. rosei, and K. tucum- anensis it is usually shorter than the subtending leaf. In all other species, with the exception of K. peninsularis, it is usually longer. The fruiting peduncle of K. peninsularis may be longer or shorter than its subtending leaf. Shape of the peduncle in fruit differs from species to species. In Kallstroemia boliviana, K. rosei, K. standleyi, and K. tribu- loides it is curved. In K. adscendens, K. californica, K. grandiflora, K. peninsularis, and K. perennans the fruiting peduncle is bent sharply at the base and is straight above. Kallstroemia parviflora may be as the latter species, or the peduncle is completely straight. It is straight in K. hintonii and K. pennellii and may be DUNCAN M. PORTER leaf of Turner 3779; b, fruit fl Fic. 17. Kallstroemia hintonii: a, leaf, b, fruit, of Hin- 8 fruit of Pollard 1295. ton 12106 (type). THE GENUS KALLSTROEMIA 81 either straight or curved in K. curta, K. hirsutissima, K. maxima, K. pubescens, and K. tucumanensis. Fruit. The body of the fruit in most species of the genus is ovoid and three to six millimeters in diameter, but it is broadly ovoid in Kallstroemia hintonii (Fig. 17a), K. hirsutissima ( Fig. 5a), K. perennans (Fig. 15a), and K. standleyi (Fig. 9a), being four to six millimeters high and six to ten wide. It ranges from glabrous [K. hintonii (Fig. 17a), K. maxima (Fig. la), and K. tribuloides (Fig. 1la)] to strigillose [K. californica (F ig. 8a), K. curta (Fig. 6a), K. hirsutissima (Fig. 5a), K. peninsularis (F ig. 14a), and K. pennellii (Fig. 12a)] or strigose [K. adscendens (Fig. 7a), K. boliviana (Fig. 10a), K. grandiflora (Fig. 13a), K. parviflora (Fig. 16a), K. rosei (Fig. 2a), K. standleyi (Fig. 9a), and K, tucumanensis (Fig. 4a)], to occasionally appressed short- pilose [K. pubescens (Fig. 3a)], or both hispid and strigose [K. perennans (Fig. 15a) ]. The length and shape of the beak on the fruit (the persistent style) differs greatly between species. In Kallstroemia adscendens (Fig. 7a), K. curta (Fig. 6a), K. hirsutissima (Fig. 5a), and K. tucumanensis (Fig. 4a) the beak is conical and shorter than the fruit body, and in K. californica (Fig. 8a) and K. standleyi (Fig. 9a) it is cylindrical above with a conical base, but it is shorter than the body. In all other species [K. boliviana (Fig. 10a), K. grandiflora (Fig. 18a), K. hintonii (Fig. 17a), K. maxima (Fig. la), K. parviflora (Fig. 16a), K. peninsularis (Fig. 14a), K. pen- nellii (Fig. 12a), K. perennans (Fig. 15a), K. pubescens (Fig. 3a), K. rosei (Fig. 2a), and K. tribuloides (Fig. lla)], it is cylindrical above with a more or less conical base and as long as to longer than the body. Species such as K. grandiflora, K. hin- tonii, K. parviflora, K. peninsularis, K. perennans, and K. rosei may have the beak becoming two to three times the length of the fruit body. There is a rough correlation between beak length and flower size. Pubescence of the beak of the fruit mostly is glabrous or strigose, being usually the same as that on the body of the fruit. Kallstroemia hirsutissima and K. rosei are unique in that there is a ring of hirsute pubescence surrounding the base of the beak. This pubescence is quite marked in K. rosei. The entire beak is hirsute in K. perennans. Another taxonomically useful character of the fruit is the 82 DUNCAN M. PORTER mericarp. In most species the mericarps are three to five milli- meters high and about one millimeter wide, but in Kallstroemia hintonii, K. perennans, and K. standleyi they may reach a width of from two to two-and-one-half millimeters. The most useful characteristic of the mericarps is in the differences found in their abaxial surfaces. This surface differs from tubercled [K. curta (Fig. 6a), K. grandiflora (Fig. 13a), K. hirsutissima (Fig. 5a), and K. peninsularis (Fig. 14a)] to tubercled or rugose [K. parvi- flora (Fig. 16a)], tubercled or rugose, and cross-ridged [K. pubescens (Fig. 3a) ], tubercled and cross-ridged, [K. adscendens (Fig. 7a) and K. rosei (Fig. 2a)], tubercled, cross-ridged and slightly keeled [K. maxima (Fig. la)], cross-ridged and more or less keeled [K. hintonii (Fig. 17a), K. pennellii (Fig. 12a), and K. perennans (Fig. 15a)], tubercled and laterally grooved [K. tucumanensis (Fig. 4a)], rugose and margins flattened [K. boliv- iana (Fig. 10a)], or rugose and margins flattened and slightly keeled [K. tribuloides (Fig. 1la)]. Four to five oblong, blunt or fungoid tubercles are present in K. californica (F ig. 8a) and K. standleyi (Fig. 92) which may become one-and-one-half to two millimeters long and become more prominent as the fruit matures. The pubescence of the abaxial surface is the same as that of the fruit body. The amount and pattern of pitting on the sides of the mericarp is variable even within the same specimen and is of no diagnostic value. However, there is a certain amount of difference in the shape of the adaxial edge of the mericarp, mirroring the shape of the styliferous axis which persists on the peduncle after the meri- carps have fallen. This edge is straight in Kallstroemia perennans and K. standleyi, curved in K. tribuloides, and more or less angled in all the remaining species but K. pennellii, where it has not been seen. HYBRIDIZATION, INTERSPECIFIC RELATIONSHIPS, AND EVOLUTION HYBRIDIZATION In addition to comparative morphology, a commonly used criterion to discern natural relationships in plants is that of hy- bridization between taxa. Such hybridization may occur in the field, or it may be artificially induced, through crosses in the THE GENUS KALLSTROEMIA 83 experimental garden. The latter type of experimentation has not been done in Kallstroemia, but there are two cases of suspected interspecific hybridization in the genus. Evidence for this hybridi- zation occurs in areas where man has transported the parent species and has modified the environment to create new habitats that can be utilized by any resulting hybrids. The majority of instances in which hybridization and introgression have been discovered in plant populations have been detected under such circumstances (Stebbins, 1950). The first case involves Kallstroemia maxima and K. pubescens. These two species are sympatric over a wide area of their ranges (Maps 1 and 4), but they appear to be at least partially isolated ecologically. Kallstroemia pubescens usually is found at slightly higher elevations and in sandier soils than K. maxima, but mixed populations of them have been seen. There is evidence for hy- bridization between the two only in their southernmost region of overlap, in Colombia and Venezuela (Map 2). Certain herbarium specimens (cited under K. maxima) from this area appear to be intermediate between the above species in sepal and fruit characteristics (the two species are very similar vegetatively), and I suspect that these specimens are of hybrid origin. Examination of the sepals and fruits of Kallstroemia maxima and K. pubescens with magnification shows these structures to be quite different in the two species (Fig. lb and 3b). The sepals of K. maxima are ovate and clasp the mature fruit, only the scarious margins becoming involute. The sepal trichomes are hirsute, of one length, and usually are appressed toward the sepal apex. The fruit in this species is ovoid and usually is glabrous, occasionally being strigose with short, rigid, curved trichomes. By contrast, in K. pubescens the sepals spread from the base of the mature fruit, the margins become sharply involute, and consequently the sepals appear to be linear or linear-lanceolate. The sepal trichomes are hispidulous, spreading stiffly, and of two lengths. They are much finer than those of K. maxima. The fruit of K. pubescens is more pyramidal than in K. maxima, and it is densely pubescent with fine, straight, appressed-pilose trichomes. These sepal and fruit characters are more or less intermediate in the suspected hybrids. In the latter specimens, the sepals either clasp the mature fruit or spread from it. The amount of involution of the sepal margins is moderate, but it does not reach either 84 DUNCAN M. PORTER extreme found in one species or the other. Trichomes are variable in length on the same sepal and usually are spreading, not ap- pressed. The sepal trichomes are not as fine or as short as those of Kallstroemia pubescens, and not as stout as those of K. maxima, but they may be as long as those of the latter species. The shape and tuberculation of the fruit approaches that of K. maxima, but fruit pubescence is of the same type as that found in K. pubescens. This pubescence is much denser than that sometimes found in K. maxima. Microscopic examination of pollen grains stained with acetocarmine following removal from unopened flowers of both the species and the suspected hybrids revealed less than nine per cent malformed grains in collections of each of the three from the same general area. When the pollen was treated with methylene blue, all of the grains were stained, even if malformed. Specimens of the putative hybrids are listed in the taxonomy section follow- ing the discussion of K. maxima. In contrast to the above situation where hybridization only is suspected, there is evidence of both hybridization and introgres- sion between Kallstroemia maxima and K. rosei where their ranges overlap in southwestern Mexico ( Maps 1 and 3). However, no plants that could be considered intermediates between the two species have been seen. Kallstroemia maxima and K. rosei both apparently have been transported to this area during his- torical times. This introduction, at least in the case of K. rosei, presumably is still taking place. The latter species is native to open, disturbed habitats in the pine-oak forests of central Mexico at elevations above about 1000 meters, while K. maxima is a more tropical species from the lower elevations of the Caribbean and Central American region. The two species have been brought together mainly in the region of the Rio Balsas Basin, where in- creased cultivation and other disturbances have provided suitable habitats for these species to overlap in their distributions. Before man’s intervention, they undoubtedly were allopatric. The two species are rather similar vegetatively, differing mainly in flower and fruit characters, although Kallstroemia rosei tends to be larger in vegetative characters. Characteristically, the fruits of the latter (Fig. 2b) are densely pubescent, the fruit body being strigose with short curved trichomes and with longer, stouter, straight trichomes forming a ring of white, hirsute pubescence around the base of the beak. This ring may be quite striking to THE GENUS KALLSTROEMIA 85 the naked eye. In specimens from this area of overlap, however, the fruits on some individuals are almost glabrous. On others, the fruits vary markedly in the amount of pubescence on the same individual, a situation unknown elsewhere in the range of K. rosei. There is also some variation in the amount of involution of the sepal margins in these specimens. Following anthesis, the sepals usually spread from the base of the fruit, and their margins be- come sharply involute. However, in the suspected introgressants, the margins may fold under, but not nearly to the extent normal for the species. The sepals also occasionally clasp the mature fruit, rather than spread from it. The fruits of Kallstroemia maxima (Fig. 1b) are almost always glabrous, but most of the collections of this species, from its area of overlap with K. rosei, are strigose to a greater or lesser extent. However, none of these specimens has the ring of hirsute pubes- cence surrounding the base of the beak that is found in K. rosei. The sepals of K. maxima in this area also vary toward those of K. rosei. They generally fail to extend beyond the mature mericarps, but here they may reach to the top of the beak. The sepal margins are more involute in these specimens than is true elsewhere, usually only the scarious margins become involuted. However, involution of the sepal margins in K. maxima never reaches the extreme of that found in K. rosei. Although the information summarized above suggests the pres- ence of interspecific hybridization in the genus, experimental proof of its existence is lacking. Such proof concerning the com- patibility of these species and the isolating mechanisms present between them is desirable, as is more information concerning the geographical relationships of both the species and their sus- pected hybrids. This vital information, along with cytological studies, undoubtedly will help in interpreting the morphological data at hand. In the absence of genetical evidence, it is thought best to consider these individuals only as suspected hybrids. INTERSPECIFIC RELATIONSHIPS The geographical distribution of the genus suggests that it has arisen somewhere in North America, probably Mexico, which is its present center of diversity and abundance. However, with al- most complete lack of a fossil record, it cannot be certain that the 86 DUNCAN M. PORTER genus did not originate in an area where it is now absent. Al- though all known members of the Zygophyllaceae now inhabit arid or semiarid habitats, it does not necessarily follow that the ancestors of Kallstroemia did so as well. It is still open to question whether the ancestors of the present-day species ranged through- out the tropics, evolving species independently in North and South America, or whether they gradually adapted to more arid conditions in the north and have since invaded both arid South America and dry, open, disturbed habitats in the tropics. This question is complicated not only by a lack of knowledge of the genetics and cytology of the genus, but also by the lack of a species or a group of species that can be definitely regarded as primitive. Comparative morphology reveals that the species of North America are more closely related to each other than to any species of South America. Each continental grouping of species shows certain relationships to those of the tropics. The evidence derived from comparative morphology regarding species relationships in the genus discussed above may be sum- marized as follows. In North America, Kallstroemia grandiflora, K. parviflora, K. peninsularis, and K. perennans form a group of closely interrelated species. Kallstroemia hirsutissima, K. cali- fornica, and K. standleyi make up another group in which the latter two species appear to be most closely related. However, K. hirsutissima shows close relationships to the Caribbean K. curta, and K. californica to K. adscendens of the Galapagos Islands. The Mexican K. rosei is closest to the Caribbean K. maxima, while K. hintonii does not appear to be closely related to any other species. In South America, K. boliviana and K. tribuloides are closely re- lated to one another and show relationships to K. pennellii. On the other hand, K. tucumanensis is very close to the Caribbean K. pubescens. The morphological bases for these relationships are discussed under the relevant species. EVOLUTION There is paleobotanical evidence for the presence of semiarid vegetation in both the northern and southern hemispheres of the New World during the late Eocene and early Oligocene, but evi- dence for desert floras in North America before the Pliocene is lacking (Axelrod, 1950, 1958). Desert vegetation types appear to THE GENUS KALLSTROEMIA 87 have developed during the latter epoch through the appearance of more arid communities in the rain shadows of the rising mountain systems in the western area of the continent. Likewise, the desert vegetation of Argentina is surmised to have developed late in the Cenozoic, concomitant with the elevation of the Andean system (Berry, 1928, 1932). The ecological effects of the Andean orogeny began in the Miocene and reached their present maximum in the Quaternary (Simpson, 1965). A rapid evolution of herbaceous plants during the late Tertiary and Quaternary has coincided with this differentiation and spread of arid and semiarid communities (Stebbins, 1947, 1949; Axelrod, 1950). This great expansion and diversification of herbs appears to have been a direct response to the factors causing a com- paratively rapid change toward a warmer, drier climate. Modern desert species have been derived by the gradual adaptation of more mesic ancestors to lowered yearly rainfall, shifting seasonal distribution of rain, and increasing ranges and extremes of temper- ature (Axelrod, 1950). As has been the case with a number of herbaceous genera, the ancestors of the present-day species of Kallstroemia adapted to this increasingly more xerophytic en- vironment by evolving annuals which inhabit areas marked by high summer temperatures and summer rainfall. A principal ad- vantage of the annual habit for these plants has been their ability to pass through the dry season unfavorable to growth as drought- resistant seeds. The rapid evolution associated with these large climatic changes has involved not only the development of adaptations to drier conditions and the rise of the annual habit, but also has been greatly aided and diversified by the alternate isolation and merg- ing of populations, providing opportunities for increase in genetic diversity through hybridization and introgression (Stebbins, 1949, 1952). Furthermore, the population structure of species in arid and semiarid regions is likely to be more favorable for evolution than that of species in more mesic habitats (Stebbins, 1952). The frequent isolation of small populations offers many situations for genetic change through natural selection and chance fixation. Occasional migration between populations further increases their genetic diversity and offers new gene combinations to the selec- tive action of the environment. Such a population structure is that most favorable to rapid evolution ( Wright, 1940). 88 DUNCAN M. PORTER Populations of Kallstroemia characteristically are local and dis- continuous. They rarely cover extensive areas, although individ- uals usually are numerous where found. Exceptions to this pattern are at times found in K. californica, K. grandiflora and K. hintonii, but such extensive masses of the plants are exceptional. This pop- ulation structure helps to explain the small amount of phenotypic diversity to be found in most local populations, and the percep- tible differences seen between such populations. The genetic makeup of the seed or seeds founding a new population, random genetic drift, and chance interpopulational hybridization, along with vigorous environmental selection, have all acted to produce these differences. On a larger scale, they have led to speciation. ECONOMIC IMPORTANCE Although by no means a genus of great economic importance, Kallstroemia, and especially K. maxima, finds many uses in the native materia medica of the areas where it is to be found. It is also a minor forage plant. In Sonora, Mexico, Kallstroemia californica (presumably the herbage) is used in the cure of insect and reptile bites (Rose, 1891). According to McGinnies (1922), the forage value of Kall- stroemia grandiflora is excellent, and it is chiefly grazed in the summer. However, another source (Anonymous, 1963, p- 72) states that, it “has very little forage value due to its rough foliage,” but it “is a good summer cover crop.” The seeds are eaten by quail in the summer and fall (Griner, 1940). These reports are from Arizona. Watson (1889, p. 43), writing of specimens from Sonora, Mexico, states that the pollen of this plant is injurious to the eyes, and therefore the plant is called Mal de Ojos (bad for the eyes). Kingsbury (1964) cites a report of Kallstroemia hirsutissima poisoning cattle under natural conditions, and sheep and goats under experimental conditions. The toxic principle is unknown. As mentioned above, Kallstroemia maxima has a number of medicinal uses throughout its range. In Jamaica, a salve is made of the plant by mixing it with suet, which is effective against ringworm (Sloane, 1707). A poultice is used for various cutaneous THE GENUS KALLSTROEMIA 89 afflictions in Cuba (Baillon, 1875; Gomez de la Maza, 1889) and Surinam (Westroiien van Meetenen, 1883). In Venezuela (Perez Arbelaez, 1956) and Costa Rica, this is used also to bring boils and similar sores to a head. In the latter country, the infusion and decoction purportedly is effective against paralysis, tetanus, and spasms ( Pittier, 1957), and in Colombia the infusion is used as a diuretic (Perez Arbelaez, 1956). Kallstroemia maxima is eaten by herbivores in Jamaica ( Browne, 1756) and Cuba (Richard, 1845) and is the only species in the genus reported to be eaten by man. According to Standley (1928), the plant sometimes is cooked and eaten as a potherb in El Sal- vador, and Perez Arbeldez (1956) reports this use in Colombia. This may be the case, but it probably results from the close re- semblance of K. maxima, at least to the native user, to Portulaca oleracea L. (Portulacaceae), a common potherb throughout Latin America. These plants grow under the same conditions and are found together. They superficially resemble one another vegeta- tively, and are known universally throughout their ranges in Latin America by the same common name, Verdolaga. In New Mexico, “the Spanish New Mexicans say that the powdered roots [of Kallstroemia parviflora—reported as “K. brachystylis”], when soaked in warm water, make a good wash for sore eyes and swollen gums. Also if taken as a tea it is an ex- cellent remedy for fever, stomach trouble and dysentary” (Anon- ymous, 1963, p. 72). Perhaps the root infusion would be efficacious in the case of K. grandiflora pollen in the eyes! Lopez (1948), writing from Chihuahua, Mexico, states that this species “es buena para el estomago” (is good for the stomach). In Peru K. parviflora is used as forage by stock (Macbride, 1949). According to Standley (1940), Kallstroemia pubescens in Guatemala is utilized as a remedy for kidney stones. The species also is appreciated in Ghana, Africa, where it was long ago in- troduced: “The leaves are used to cure constipation. They are powdered in a morter with palm nuts and drunk as soup in 3 doses. This is also believed to induce conception. The leaves are put into water, salt is added, and when they have been boiled, the liquor is drunk as another cure for constipation” (Irvine, 1930, p. 419). In Argentina both Kallstroemia tribuloides and K. tucumanen- sis are eaten by herbivores (Ruiz Leal, 1947, 1951). The former 90 DUNCAN M. PORTER species apparently is the only one in the genus, except perhaps for K. grandiflora, which has been raised as an ornamental: “The seeds of this plant may be raised on a hot-bed, and when the plants have grown 2 or 3 inches, they may be planted out in the open border in a sheltered situation, in the month of May” (Don, 1831, p. 769). ACKNOWLEDGEMENTS I am particularly indebted to the generous counsel provided by Dr. Reed C. Rollins, Asa Gray Professor of Systematic Botany and Director of the Gray Herbarium, Harvard University, who guided me during the course of the present study. His helpful suggestions and criticisms, and his assistance in obtaining funds for research and field studies are gratefully acknowledged. Innumerable questions have been answered and assistance and suggestions offered by many persons associated with the Harvard University Herbarium during my tenure there, including Dr. J. H. Beaman, the late Dr. G. K. Brizicky, Mr. M. A. Canoso, Dr. W. R. Ernst, Dr. R. C. Foster, Mr. P. S. Green, Dr. T. G. Hartley, Dr. R. A. Howard, Dr. K. R. Khanna, the late Dr. C. E. Kobuski, Dr. L. I. Nevling, Jr., Mrs. L. Riidenberg, Dr. H. P. van der Schijff, Dr. B. G. Schubert, Dr. O. T. Solbrig, Dr. L. M. Srivastiva, Dr. A. F. Tryon, Dr. R. M. Tryon, and Dr. C. E. Wood, Jr. Mrs. Lazella Schwarten was most helpful in locating and obtaining bibliographical ma- terial. Collections for cytological study have been supplied by Dr. Nevling; Dr. Beaman, Dr. S. K. Harris of Boston University, Dr. Howard, Mr. J. D. Porter of Ventura, California, and Drs. J. H. Thomas and I. L. Wiggins of Stanford University have provided herbarium specimens of their collections. Dr. Foster has kindly written the Latin diagnoses for the new species. The drawings of the leaves and fruits were made by Mr. Arnold Clapman. My sincere appreciation is offered to those persons cited above and also to the officers of those institutions which loaned materials for my study, or provided facilities during my visits to the herbaria in their charge. Finally, many individuals, too numerous to mention, have my gratitude for their assistance during the field studies, supplying either information, transportation, facilities, or companionship, and sometimes all four. Field studies (June and July, 1962, in the southwestern United States; and from August, 1963, through January, 1964, in Jamaica, Colombia, Cen- THE GENUS KALLSTROEMIA 91 TAXONOMIC History Since the the foundation of the genus by Scopoli in 1777, most of the pub- lished material on Kallstroemia has been concerned with either distributional and ecological information or the description of new wer ies. The most recent work of a revisional nature was done by mr a in 1910 and covered North America only. It is now very much out of dat The following list is a chronological ta ae history of | the gen 1696: ipl ne published the first notice of the plant later to bets ed Kallstroemia maxima, “Tribulus terrestris major flore maximo odorato.” Thus, epithe bs svineenite is based not on floral size, as many have assumed (e.g., eat 1837), but on floral odor 1707: The first illustration of a Kallstroemia (K. maxima) was published Sloan , 1753: ‘Lin nnaeus described Tribulus maximus (= Kallstroemia maxima) from Jamaica, citing Sloane in the protologue. 1777: Scopoli published Kallstroemia, basing it on Satu maximus = Tri am ne Loefl.” (= Tribulus maximus L.). The derivation of the e was never explained. Some authors gest it was compoun om “Greek Kallos, autiful, ia, a genus of Capparidaceae” (Jepson, 1936, p. 4 while o believe it to be “in honor roem, obscure contemporary of Scopoli” (Munz, 1959, p. 159). Scopoli made no combinations in the genus. 1818: Nuttall described Tribulus trijugatus (= Kallstroemia maxima) from rgia. 1855: The fundamental differences between fruits of Tribulus maximus and those of the other known species of Tribulus were recognized by A. Jussieu. He stated that perhaps a new genus should be based on the former species, apparently unaware that Scopoli already had done so on the same basis 48 years previously. 1826: The genus Ehrenbergia was described by von Martius from Brazil. 1827: Von Martius published Ehrenbergia tribuloides (= Kallstroemia tribuloides), correctly ergtinges its affinities with Tribulus, but rig boners” f he was unaware that it was actually the second known species of stroemia. 1827: Sprengel published Tribulus brasiliensis (= Kallstroemia tribuloides) from Brazil, basing it on Ehrenber, a tribuloides. Ehrenbergia Mart. is a later homonym for a genus erected by x 5a in the com ea 1828: Reichenbach Nveay the first to recognize use the name Kallstroe- mia since its publica 1831: George I Don. ‘destrod Tribulus pubescens (= Kallstroemia pubescens) from the “Cape Coast,” now Ghana. This is the only species of Ilstroemia ate: to occur outside the New World, also being introduced to ip eria and India. ? : Wight and Arnott scree that — was distinct from Tribulus but they made no new combinations in the gen 1835: The inecias Heterozygis was erected by — who based it on Tribulus maximus lished no new panera 1836: The ~ combination was made in Kallstroemia, K. cistoides, by Endlicher. However, the species is actually a Tribulus, T. cistoides 1837: Macfadyen published Tribulus decolor (= Kallstroemia | maxima) from Jamaica. 1837: Meisner published Kallstroemia tribulus (= Kallstroemia maxima), basing it on Tribulus maxi 92 DUNCAN M. PORTER 1838: Hooker and Amott were the first to correctly place a species, K. maxima, in Kallstroemi 1840: Rafinesque published Tribulus dimidiatus (= Kallstroemia maxima), based on T. t trijugatus. 18 The combination Kallstroemia a aeisiong was published by Steudal, who wrongly attributed it to Wi ight and 1841: Steudal published Tribulus pibesunss an n orthographic error for T. trijugatus. 1849: Robert Brown a = basic differences in the fruits of Kallstroemia, Tribulopis, and Tribu 1849: J. D. Hooker published Ealiveccenia minor (=K. pubescens) from Ghana, basing it on the same type as Tribulus pubescens Tribulus adscendens (= Kallstroemia adscendens) was described from the Galapagos Islands, Ecuador, by Ander 1859: G ee divided Tribulus into sections, Eutribulus and ee basing the division on characters of the fru ay i ae published the combination Tribulus 1 maximus var. ad- fers ak (= Kallstroemia adscen 1862: J. D. Hooker treated Kallstroemia and Tribulopis as subgenera of Tribulus 1867: Hooker now placed Kallstroemia and Tribulopis as sections of Tribulus. 1868: Tribulus oe var. minor (= Kallstroemia pubescens) was described by Olive 1872: Baillon deca that the differences between Kallstroemia and i were not sufficient to warrant the separation of the former from Tribulus 1876: Tribulus californicus (= ne californica) was described by Watson cis Baja California, Mexi 1876: Brew aad Watson pu ublishe 2 the combination Tribulus grandi- Hea ‘foc abrtinacs grandiflora) erroneously ascribing it to Bentham and Hooker. 1877: Kellogg ae Tribulus fisheri (= Kallstroemia grandiflora) from Scere, exic er ne trea ating them as genera separate from Tribulus, Gray now indicated that Kallstroemia and Tribulopis should be considered as — of Tri d Kallstroemia californica. 1890: Engler divided Kallstroemia into two sections, Eukallstroemia and nozygium, the former with nine species, the | ith two species. He also placed Tribulopis as a synonym of Kallstroemia, and seven of the species lstroemia and both those in Thamnozygi new combinations from this I — Tribulus. The rayon tw cies in section Eukall- was Sip alin Cuba. 1895: Vail ba ean the combination Kallstroemia californic 1897: Kallstroemia brachystylis (= K. californica) was Saceiad by Vail from New M exico. 1897: Gray recognized three sections in Tribulus, two of which con- stituted Kallstroemia, the other being Tribulus s. str 1897: Robinson published the combination Tribulus brachystylis (= Kallstroemia californica). THE GENUS KALLSTROEMIA 93 1898: Kuntze one Tribulus maximus var. roseus (= Kallstroemia boliviana) from 1898: ew see ia sallef ra was described from Texas by Norton 1900: Cockerell i Kallstroemia grandiflora var. arizonica te = granifora from 902: The ae Kallstroemia adscendens was published by Robin- son, reversing OM aaa belief that Kallstroemia should be considered a synonym of Tri. 1903: Vail sacibel Kallstroemia hirsutissima from New Mex 1910: Rydberg, in the most complete revision of Zalisteouenlat ee date, serrat, West Indies; K. . glabrata (aK. seeps Sa oan Guerrero, Mexico; intermedia (= K. parviflora) from Texas; = s (= K. pubescens) om Sinaloa; and K. rosei from Morelos, Mexic 1913: Britton and Brown chose Tribulus maximus as the lectotype species of oo : Kallstroemia laetevirens (= K. parviflora) was described from New “ees ‘by Thornber 1913: Rydintg described Kallstroemia curta from Curacao, West Indies. 1924: Kallstroemia incana (= K. curta) was described by Rydberg from Hispaniola, West Indies. : Engler maintained his subgeneric classification of Kallstroemia, with the exception that 18 species were now included in section Eukall- stroemia and two in section Thamnozy 1935: L. O. Williams described 4s eae hirsuta (=K. perennans) from Texas, not realizing that the name was a later homonym of a combina- tion made by Engler in 1890. 1936: Standley déatriienk Kallstroemia boliviana from Bolivia. Although Standley was considered to be an expert on the Zygophyllaceae, this was the only species he ever published i in this genus : Ka ia tucumanensis was ‘described from Argentina by Descole, O’Donell, and Lourteig. 1939: Kearney and Peebles A eee - combination Kallstroemia californica var. brachystylis (= K. cali 1950: eats published lento sspeaeet a new name for William’s K. poe 1955: “The combination Kallstroemia pubescens was published by Dandy. MATERIAL EXAMINED The first set of sch collections has been deposited in the Gray Herbarium of Harvard University. Specimens from 31 institutions have been studied f ad GN Ministerio vi Agricultura y Ganaderia, Man agua, Nicaragua. usMc Universidad de San Marcos, Guatemala City, Guatemala. TAXONOMIC TREATMENT Kallstroemia Scop., Introd. 212. 1777. TYPE SPECIES: Tribulus maximus L. [Kallstroemia maxima (L.) Hook. & Arn.]. 94 DUNCAN M. PORTER Ehrenbergia Mart., Nov. Gen. Sp. Brasil. 2:72. 1826. Not Ehrenbergia Spreng., Neue Entdeck. 2:129. 1821. TPE species: Ehrenbergia tribuloides Mart. [Kallstroemia tribuloides ( Mart.) Spreng.]. Heterozygis Bunge, Mem. Acad. Sav. Etr. St. Petersb. 2:82. 1835. TyPE species: Tribulus maximus L. A diffusely branched, prostrate to decumbent or ascending; spreading radially from a thick, fibrous central tap root to 1 m or mor and about 1 m high, branching from basal nodes; terete, somewhat ent, coming striat ing, ow-green to reddish, drying yellow, fibrous ing in a foliaceous, subulate, apiculate, pubescent mucro ca. 1 mm long; petiole and rachis pubescence as on stem. Leaflets 2-10 pairs, opposite, entire, elliptical to broadly oblong or obovate, apex acute to obtuse, mucronate, o 2. wide, somewhat unequal in size, those on one side of rachis slightly smaller, lowest i i orward and more falcate; sharply at base and straight above in fruit. Flowers solitary, hypogynous, pentamerous or rarely hexamerous, perfect, regular, polypetalous, syncarpous, 7-60 mm in di ( om base of mature fruit; persistent or rarely caducous. Petals 5(-6), free, th t base, same color as petal base. Anthers globose or ovoid to linear-oblong or rarely linear, bilobed, sub-basifixed to versatile, yellow THE GENUS KALLSTROEMIA 95 through comes ee ni less than 1-2 mm in diame r 2-4 mm long; spherical, nF Sc cee through orange to red. Ovary superior, ‘sessile, and -loculed, globos id and 1-3 i p ati aborting. Style 1, cylindrical to broadly conical, less than 1-8 mm long, more or less 10(—12)-ridged, ag pe pica to form beak on fruit. Stigma capitate, oblong, or oo less than 1-7 mm long, terminal or rarely extending down st to bas style, 10-rid “tg or -lobed, papillose or rarely coarsely canescent, chen F je 10 (-12)-lobed, ovoid, occasionally scueak pyramidal, mm n diameter or 3-6 mm high and 3-10 mm wide; gla- ous epigeal; testa smooth, white, membranaceous; embryo straight, cotyledons ovoid, radical conical, let epicotyl rudimentary; endosperm none. KEY To THE SPECIES OF KALLSTROEMIA’ Information are age geographical distribution is approximate only i is poet rimarily for the convenience of user of the key. The pubesce ng ie as used in the are 1. Leaves obovate, Aes tae of mature leaves largest 2. Mature mericarps with 4-5 blunt elongate tubercles to 1.5 mm long; sepals ly deciduous; stems hirsute and strigose (southwestern United States and northern Mexico; Fig. 8a, 8b) a ca et eee ee CD eben cy car gee eens alifornica. 2. Ma’ mericarps rugose to —. cross-ridged, or keeled, tubercles never elongate; — rsistent; stems hirsute and sericeous. 3. Ov wed , style and beak “ae or oe eal strigose hirsute piehies, i a eastern coastal United States, tropical Mexico to northern South 1 America; Fig. 1a, BO ce ee oe ee 3. Ovary an y pubescent, style and beak glab Papp stigma clavate, Tr or if ca bell then style hirsute body appr short-pilose; sepals hirsute and ous. 4. Flowers 2-3.5 cm in diameter, style as long or longer than conical ovary, beak as long or ‘ue than fruit body. 96 DUNCAN M. PORTER OU - Sepals clasping and almost entirely covering mature mericarps, only scarious margins becoming involute; beak ca. as long as fruit bod , stri = stigma oblong; peduncles longer than ot gS gs, lies ae wn” Z o ae) Ou @ EF fe) oy . 5 ou pt) n & 9 a 5 5 Au re = ' ober ree ha a eig Pah poner ee eed ee te K. rosei. 4. Flowers 1.5 cm or less in diameter, style as long or usually shorter than globose, ovoid, or pyramidal ovary, beak shorter than fruit od ad 6 se . Sepals clasping mature fruit, only scarious margins becoming involute; fruit broadly ovoid, 4-5 mm high, 6-8 mm wide, beak hirsute (southwestern United States and northern Mexico; Fig. 5. K. hirsutissima. : Sepals icladant from base of — fruit, margins becoming strongly involute; fruit ovoid, mm in diameter, beak strigose, appresse short-pilose, or eben 7. Sepals hirsute and strigose; stigma cl avate; fruit strigillose, eak 1.5-2 mm long and widely eae (Cuba, Hispaniola, and Netherlands Antilles; Fig. 6a, 6b) ................ ssw ae Aces oepib han’ Siw Sire cee annem eae a 6. K. 7. Sepals hispidulous with trichomes of two lengths; stigma ee fruit appressed short-pilose or strigose, beak narrowly conical or cylindrical above. 8. ints 9-15 mm in diameter, petals 6-11 mm long and wide; ovary pyramidal, 3-5 mm ~~ gen Eo Sey fruit x vadbiteat appressed short-pilose, long (Caribbean region, tropical Mexico to Pail West ica, India; Fig. 3a, 3b)............ 3. K. pubescens. 8. Flowers 4-8 mm in diameter, petals 3-5 mm long and 2-3 mm wide; ovary bt ca. 1 mm in diameter, style 1 mm long; fruit strigose, beak 2-3. . mm long (Argentina and Bolivia; Fig M6, So ee pee Os eet eel ec aii K. tucumanensis. E Bg te elliptical, middle leaflets of agama" leaves largest . Stem Snag 5 retrorse; s ending from along upper 1/3 ca. entire length = a gon: eu papillose (southern Baja 2 California, rei Pie. AOR SO 14. K. peninsu ubescence fvineas stigma usually terminal and surface papillose, ory yee. along ye ue of style then surface coarsely canescent with gray tri hom 10. Flowers 1 cm or less in Sak. style stout, conical, shorter than : 11. Leaflets 2-3 pairs; sepals LU aeag ua peduncles longer than subtending leaves in fruit; stems hirsute and sericeous (Gala- pagos Islands, Ecuador; Fig. Oe OD od ee a or Bes 7. K. adscendens Leaflets 3-7 pairs; sepals usually deciduous; pence shorter than subtending leaves in fruit; stems hirsute and strigose eects United States and northern Mexico Fig, 8a, 8b) cali ifornica. ~~ i THE GENUS KALLSTROEMIA 97 10. Heian ws cm or more in diameter, style conical to cylindrical, ae r th vary. rae wand fruit glabrous. Flowers 3-6 cm in diameter: tals white, agin i " base yeliow-ghens or rarely ais filaments Pet ge ; stems hirsute and sericeous, leaflets 5-7 pairs ( vig eee Mexico; Fig:.17aj:17b) cases aug, asa is 7. K. hintonii. 13. Flowers 1.5-2.5 cm in diameter; petals orange, base sometimes darker; filaments filiform to subulate; stems —— leaflets 3-6 pairs eg i Bolivia, and Fig. lla, en sear ats . K. tribuloides. 12. Goa. re fruit pubesc Sepals sericeous, so ait from base of myn fruit, sg becoming strongly involute; beak from 1/2 as lon as long as t body; mature Goren s with gt several elongate blunt or slightly ‘fungoid tubercles to 2 ong (Oaxaca, Mexico; Fig. 9a, 9b) .............. my ORS Bre | aa ee eae ane 9. ps ng 14. Sepals hispid and strigose, or if sericeous ‘i ys mature mericarps and margins not becoming involute; beak from as long as fruit y to three times as long; mature mericarps rugose to phones or cross-ridged and ee tubercles never elongate. 15. Fruit densely hispid and strigose; — pat ae upper 1/3 of style, surface coarse with short gray trichomes a Stes ie. Lila; 3500 iss he ae K. perennans. 1 pe . Fruit strigose or strigillose; stigma terminal, papillose, silve pont Ol 16. Sepals se niger clasping mature mericarps, mar- gins not becoming involute; stems strigose ( Peru; Fig. 12a, 1 3b) URS ee (a eee 12. K. pennellii. Sepals hispid and_ strigose, beyond mericarps, shriveling and turnin ng brown, —_ > sass ns K grandiflora 17. Flowers 125, cm in ge ‘petals 5- ] mm wide; stigma sista ca. 1 mm aes peduncles 1-4 cm long i fruit (central and southwestern United States, northeastern and 1 Mexico, Peru; Fig. 16a, 16b) .................--- 16. K. parviflora 1. Kallstroemia maxima (L.) Hook. & Arn., Bot. Beechey 282. 1838 The author combina uted to “Torr. & Gray,” Fl. N. Amer. 1:213. 1838. pabbeein noes fi the “ois Part 2, pp. 185-360, however, 98 DUNCAN M. PORTER took place in October, 1838 A cane gs 1893), while Part 6, pp. 241-288, of Hooker and Arnott was published before August, 1838 (Marshall, 1950). The an Peas also occasionally is attributed to “Wight & Arn., Prodr. They wrote, “Kallstroemia, oe: _( containing Trib. i tinct frome 7 a te Mart , thus recognizing K allstroemia as dis- pee tribulus Meisn., Pl. Vasc. Gen. 2:43. 1837. nom. superfl. Based on “Tribulus maximus Loefl .”, cited as a synonym. Tribulus decolor Macfad., F). Jamaica 186. 1837. nom. superfl. Based on T. maximus L., cited as a synonym. Tribulus dimidiatus Raf., prs Bot. 176. 1840. nom. superfl. Based on Tribulus trijugus Steud., a Bot. Js 2. 2:699. 1841. nom. superfl. Tribulus tuberculatus Ses. & Moc., F1. Mex. Ed. 2. 109. 1894. type: Cuba, near Havana, Martin Sessé Shoiotyne presumably at Ma, not se Kallstroemia cane scens Rydb. in Vail & Rydb., N. Amer. FI. 25:113. 1 1910. TYPE: Mexico, Sinaloa: Rosario, 7 July 1897. J. N. Rose 1547 (us, holotype; GH, NY, iso ual; seine prostrate to o decumbent, t to 1 m or more Wk sericeous and gly hirsut patra stipules 3-5 mm : ca. 1 mm wide; leaves pred 1-6 cm 15-5 diameter; sepals ovate, 3-8 mm long, 2~3 mm wide, as long or little shorter as long as an , hirsute, trichomes appressed to spreading, i in flower ca. style, in fruit clasping but not entirely covering mature mericarps and shorter an only scarious mar becoming eters persistent; petals white THE GENUS KALLSTROEMIA 99 FLOWERING DATES. Flowers year around, whenever sufficient moisture is available for seed germination and plant growth. DISTRIBUTION AND HABITAT. Disturbed areas from sea level to about 1350 m, usually at lower elevations, from northern South America north through the Caribbean to South Carolina and through western Central America to Sinaloa on the west and Tamaulipas on the east coast of Mexico, also introduced into Texas (Map 1). Sympatric with Kallstroemia curta, K. hintonii, and K. standleyi, and over much of its range with K. pubescens; to the northwest overlapping slightly with K. californica, K. grandiflora, K. hirsutissima, and K. parviflora, and more so with K. rosei. DISTINGUISHING CHARACTERISTICS. Kallstroemia maxima is easily recognized by its combination of obovate leaves, usually three to four pairs of leaflets, white to pale orange flowers (the petal bases are white to green or rarely red) 7-25 mm in diameter, hirsute sepals which clasp the mature mericarps, only the scarious mar- gins of the sepals becoming involute, usually glabrous ovaries and fruits, and a capitate obscurely ten-lobed stigma. Kallstroemia pubescens and K. rosei are the only species from the same area with which it is likely to be confused. However, in the latter species, the sepals spread from the base of the mature fruit, and the sepal margins become sharply involute, thus the sepals appear to be linear or linear-lanceolate. The sepal pubescence in K. pubescens is hirsutulous, in K. rosei hirsute and strigose; and both have pubescent fruits. There is some overlap in flower diameter be- tween these three species, but the flowers in K. maxima on the av- erage are larger than in K. pubescens and smaller than in K. rosei. The same relationship holds for overall plant size, and K. maxima also tends to be less decumbent than K. rosei. In addition, in areas where K. maxima and K. rosei overlap in their distributions, and in localities where both K. maxima and K. pubescens are to be found, petal color is yellow to orange in K. maxima and white in the other two species. RESENT. SPECIMENS EXAMINED. UNITED STATES. TEXAS. Washington Co.: Brenham, Lehmann, 10 July 1934 (GH, TEX). SOUTH CAROLINA. Charleston Co.; Charleston, Elliott s. n. (PH). GEORGIA. n. (PH : Doboy I. ? “ MO, NY, US). . Es 0.: waste places, Pensacola, Mohr, July 1874 (F). Duval Co.: Jacksonville, Williamson, Aug 100 DUNCAN M. PORTER 1894 (PH). St. Johns Co.: St. Augustine, seg a etc., Curtiss 6424 (GH, MO, NY, SMU, UC, US). Hillsborough Co. Tampa, waste ground, Barnhart 2235 ( NY). Monroe Co.: Ke ey West, low waste places, Curtiss 416 (BM, F, MO; NY, PH, US). MEXICO. SINALOA: Mazatlan, Gonzdlez Ortega 7295 (CAS, F, MEXU, US); near Rosario, sand dunes, Rose, Standley & Russell 14641 (GH, NY, US). NUEVO ag a Monterrey, Black 39-7458 (NY). ico, ca. 15 m, Palmer 116 (BM, CAS, F, GH, MO, NY, US). NAYARIT: near eaters pee rile fields, Rose, ‘Standley & Russell 14400 (F, GH, NY); near San Blas, Ferris 5388 (DS, GH, M hes JALISCO: outskirts of Am meca, roadside, 1225 m, MeVaugh 18579 MICH); Puerto Vallarta, Howell 10352 (CAS, cinch rere) LIMA: ee print 98 (US); Manzanillo, edge of dus ne a treet, hing 1481 - Rose, Painter & Rose 9436 (US); near Yautepec, pedregal, Rose, Painter & Russell 8598 (MEXU, gos US). VE Cuitldhuac, Matuda 1420 (DS, GH, MICH, MO, NY); Mocambo, in ro each, Porter 1461 (CAS, PH, US). CHIAPAS: between Mazapa and Motozintla, 1200 m, Matuda 4831 (GH, LL). CAMPECHE: Ciudad del Carmen, Mell 2074 (NY, US); Tuxpena, some 1217 (ARIZ, DS, F, GH, LE, MEXU, MICH, MO, NY, UC, US). YUCATAN: Chichen Itz, Steere 1022 (BM, MEXU, MICH, MO, NY); Izamal, Gaumer 462 (BM, CAS, DS, F, GH, MICH, MO, NY, PH, SMU, UC, US, WIS). OUINTANA ROO: Chichankanab, Gaumer 1780 (BM, CAS, DS, FF, UC, ated GUATEMALA. PETEN: ear La Libertad, Aguilar H. 175 (F, MICH, MO). HUEHUETENANGO: near Cuilco, thickets along Rio Cuilco, 1350 m, ge yes 50759 (F, bs QUICHE: without locality, Aguilar G. 492 (F). 1 L: near Puerto Barrios, open bank, sea ‘vel Standley 25147 (GH, oeey et MARCOS: Océs, sands, 1-2 m, Steyermark 37853 (F). RETALHULEU: Champerico, Kellerman 4978 (US). SUCHITEPEQUEZ: Tiquisate, 100 m, Steyermark 47630 (F). SOLOLA: Guatalén, 190 m, : u rG (F). ZACAPA: Gualan, waste places and st ego 620 ft, Deam 6288 (F, GH, MICH, MO, NY, US). AMATITLAN: Rio Amatitlan, 3900 ft, J. D. Smith 1936 (GH, US). ESCUINTLA: near P bag , ey roadside, sea level, Standley 64062 (F, NY). SANTA ROSA: Cerro Gordo, 3500 ft, Heyde & Lux 3958 (F, PH, US). JUTIAPA: near Jutiapa, Decale open slope, ca. 850 m, Standley 74980 (F BRITISH HONDURAS. COROZAL: Santa . Rita, occupied cared Lundell 4773 ( ARIZ, DS, F, er MEXU, MICH, MO, NY, TEX). CAYO El Cayo and vicinity, Chanek 159 (F, MICH THE GENUS KALLSTROEMIA 101 EL Scere eben gece ee Santa Ana, Porter 1280 (GH, aera’ SONSONATE: r Armenia, dry field, Standley 23538A (DS, US). LIBERTAD: La Se, ctr we Porter 1260 (DS, GH, ITIC). Are SALVADOR: San Salvador, Calderén 349 (GH, MO, NY, US). LA PAZ: Potrero Santo, ca. 60 m, Tucker 892 (F, UC, Cane LA A UNION: La Unidén, eer cece on edge of forest, Grant 706 (F, GH). URAS. CORTES: Finca Zapote, near a Lima, 30 m, lige & Ps a 4 12458 (F, GH). COMAYAGUA: near + Comaya gua Standley & Chacén P. 5614 (F). MORAZAN: ar Zamorano, ie along Rio de la Orilla, 850 m, Molina R. 261 (F, CH. ‘MO. . EL PA RAISO: Yascaraén, open be nk, 930 m, Standley 25790 (F). CHOLUTECA: near Pespire, 160-200 m, Standley 27259 ARAGUA. CHINANDEGA: Goad Green n ¢ Greenman 5828 (GH, MO). MANAGUA: Managua, railroad track oe 1190 (DS, GH) M YA: Masaya, Baker 211 ie , , MO, NY, ). CA ae: near PANAMA: near ZONE: between Panama and Corozal, 20-30 m, Pittier 4443 (F, GH, NY, U BAHAMA ISLANDS. FORTUNE: Hitchcock, Nov 1890 (MO). NEW PROVIDENCE: hill S of Lyford Cay, Degener 18742 (GH, NY, PH). CUBA. PINAR DEL RIO: near Mariel, sandy flat ground set coast, Palmer & Riley 711 (NY, US). HAV. VANA: Havana, Schott 97 (BM). TA : : Auaras, banks of Rio Arimao, Gonzales 539 (A, BM, IJ, MICH, NY). > ORIENTE: Hicotea Estate, banks of Rio Cafias, Bro. Clemente 5699 (GH, CAYMAN ISLANDS. GRAND CAYMAN: Bosun Bay, near Hell, pasture, M, MO). JAMAICA. HANOVER: Lucea, Hitchcock, 9 Jan 1891 (MO). WEST- MORLAND: New H a Ww Proctor 11202 ). SI. JAMES: Montpelier, Churchill, 16 Mar 1897 (GH). ST. ELIZABETH: Giddy Hall, Maxwell, Apr 1926 (B M). CLARENDON: halfway — “Amity Hall and Portland Cottage, roadside at edge of pe tings. Porter 1039 (GH). ST. oS ATHERINE: Spanish Town 00 ft : Campbel 6298 (BM, UCWI). ST. ANDREW: Mona, weedy fd, Crosby, H espenheide & Anderson 69 (F, aH MSC, UC). ST. THOM- AS: Albion, Orcutt 1421 (UC). HAITI. NORD: Bayeux, dry str streambed, sea level, Nash 92 (F, NY). and waste places, Leonard 5194 (GH, US). DOMINICAN ee MONTE CRISTI: Santiago, margins o Yaque, Jiménez 1844 (U eos Rose, Fitch & Russell 4012 ne US). BARAHONA: near (Oe Fr. Fuertes 1574 (BM, F, GH, NY, US). PACIFICADOR: omen sme railroad, near sea level. Abbott 102 DUNCAN M. PORTER 643 (US). SANTO ee ae Santo Domingo, seashore, von Tiirckheim 2547 (BM, GH, MO, US). MACORIS: 20 km W of San Pedro de Macoris, limestone neg Howard %& Howard 9496 (GH, NY, PUERTO RICO. AGUADILLA: Camuy, Underwood & Griggs 197 (NY, US). MAYAGUEZ: near Yauco, Heller 6296 (CAS, F, GH, MO, NY, PH, US). ARECIBO: near Manati, cultivated area, Sintenis 6731 (BM, F, GH, MO, NY, US). PONCE: Cayo Muertos, waste grounds, Britton, Cowell & Brown 4985 (F, MO, NY, US). SAN JUAN: Cataiio, waste ground, Heller & Heller 114 va NY, Us). GUA YAMA: ragesnes Kuntze 578 (NY). y, VIRGIN ISLANDS. 24 gf THOMAS: Eggers 8 (F, NY). TORTOLA: Ex- periment Station, waste places, Fishlock 131 (NY, PH). ST. CROIX: road- side, Ricksecker 138 (F, GH, MO, NY, UC, US). WARD ISLANDS. ANGUILLA: near Blowing Point, roadside, Proctor 18685 (BM, IJ). ST. BARTHELEMY: Gustavia, 2 m, Questel 193 US). ST. EUSTATIUS: Orangestiid, along roads, Stoffers 3905 (A). ST. KITTS: near Basseterre, roadside, Britton & Cowell 137 (NY, US). AN- TIGUA: Cedar Valley, cultivated lands in drier districts, Box 871 (GH). yr bilengenaeese Basse-Terre, Fr. Duss 2427 (US). DESERADE: Grand Anse, roadside, 1 m, Proctor 21294 (IJ). DOMINICA: Grand Savannah, pony coastal xerophytic shallow-soiled areas, Hodge & Hodge 3762 (GH, NDWARD ISLANDS. MARTINIQUE: St. ie Hahn 987 (BM, ee ST. VINCENT: sandy land or cultivated fields, Smith & Smith 584 (GH). BARBADOS: near Combermere School, Dash py tF. NY, US). GRENADA: St. George’s, ditch, Broadway, 2 Apr 1905 (NY). COLOMBIA. ATLANTICO: Cabica, eo in Rio Magdalena, Bro. Elias 1218 (F). MAGDALENA: Santa Marta, 2 50 ft, H. H. Smith 572 (MICH, TEX, UC, WIS). BOLIVAR: near leat ca. sea level, Killip & Smith 14039 (COL, F, GH, NY, US). CORDOBA: Monteria, riverbank, 20-50 m Pennell 4706 (F, GH, MO, NY, US). VENEZUELA. ZULIA: Maxacailo: s. coll. (CAS). TRUJILLO: La Con- cepcién, 2500 ft, Reed 1005 ( MICH). DISTRITO FEDERAL: Blandin, waste places, Pittier 11618 (NY, US). ANZOATEGUI: Guanta, roadside, ca. sea level, Potter 5149 (US). BOLIVAR: Ciudad Bolivar, near river, ca. msl Holt &G pg as fiche Socata and labeled sat D. sk 7 May 1948. Kern Co.: Kern River Canyon, munication). There is also _ specimen of Tribulus cistoid CAS bearing Skoss’ name and the same ity data. I apt ndiated evidesly ( Porter, 1963) that this latter alsa as made in ut it, too, appar- ently was collected in the Dominican Republic or Cr Crafts, COMMON NAMES. Many common names have been applied to Kallstroemia maxima. This is to be expected with a plant that is so frequent and widespread among peoples who often utilize their natural flora and its products. The names reported in the litera- THE GENUS KALLSTROEMIA 103 ture, or noted on herbarium labels, are Abrojo (Cuba, Nicaragua, Puerto Rico); Chax-chauxnuc (Quintana Roo, Mexico); Cresson Courant (Guadeloupe); Golondrina, Guia de Parra, Hierba de Parra (El Salvador); Hierba de Pasmo (Venezuela); Hierba de Pollo (Colombia, El Salvador, Panama); Maconcherie (Dominica); Mata (Costa Rica); Pale-flowered Turkey-blossom (Jamaica); Parsley (Grand Cayman); Patagon (Martinique); Police Macca (Jamaica); Pourpier Batard (Guadeloupe); Pourpier Courant, Pourpier Rampant (Martinique); Shanap- mucui (British Honduras); Talcacao (Costa Rica); Taraya (El Salvador); Verdolaga (Costa Rica, El Salvador, Venezuela); Verdolaga Blanca, Verdolaga del Caballo, Verdolaga del Monte, Verdolaguita (El Salvador); Xichiak (Quintana Roo); Xichilak (Yucatan, Mexico); Yerba de Gallina (Honduras); and Yerba de Paloma (Guerrero, Mexico). The prevalence of Verdolaga or its derivatives as a common name for this species throughout much of Latin America is ex- plained by its resemblance to the Verdolaga Vera (true verdo- laga), Portulaca oleracea L. (Portulacaceae). The latter is another weedy plant common to the same area as Kallstroemia maxima, superficially similar to it, and much used by the native popula- tions as a potherb. It should be noted that the name Caltrop is often given to various members of the genus in manuals and floras, but it is to be doubted that anyone but a botanist would apply this common name to a Kallstroemia. It is more aptly applied to the spiny- fruited species of Tribulus, which show a decided resemblance to their namesake, a medieval weapon used to impede charging cavalry. TAXONOMY. The name Kallstroemia canescens has been applied to specimens of K. maxima from southwestern Mexico with strigose fruits. Whereas the fruits of K. maxima usually are glabrous, individuals with strigose fruits are found occasionally. They come from scattered places throughout the range of the species, and taxonomic recognition on the basis of this single character is not warranted. VARIATION. In Kallstroemia maxima there is a noticeable amount of variation in stem color, in flower size and color, in anther and pollen color, and in peduncle length and the amount of peduncle curvature at fruiting time. Variation is particularly striking in this 104 DUNCAN M. PORTER species because these morphological characters may vary within the local population. Other species of the genus may be equally variable with respect to the same characteristics, but the variation occurs between populations, apparently never within them. This interpopulation variation is especially common in Central America. In Costa Rica, for instance, where Kallstroemia maxima was observed in the town of Puntarenas the populations con- sisted of two morphological types. One type had yellow-orange flowers 1-1% cm in diameter with yellow anthers and pollen, the sepals were about two-thirds as long as the petals, and the ped- uncles were 2-2% cm long, bent strongly at the base and straight above. The second type had pale yellowish-white flowers 7-8 mm in diameter with red anthers and pollen; the sepals were as long as the petals, and the peduncles were 6-14 mm long and curved through their entire length. An accurate count of the two types in the populations was not taken, but they were estimated to be present in approximately equal numbers. Intermediates were not seen. Progeny of collections of both types (Porter 1135, 1136) proved to be self-compatible when grown in the greenhouse. The situation discussed above in Kallstroemia maxima is similar to that described by Lewis (1963) for Gayophytum “taxon B” (Onagraceae). Discontinuous phenotypic variation in popula- tions of the latter autogamous taxon could have a simple genetic basis, and if so such differences do not warrant formal taxonomic recognition. The same conclusion is applicable in this instance to K. maxima, especially in light of the populations reviewed below, although data concerning cytology and breeding behavior (i.e., the extent of outcrossing) are lacking. Populations of Kallstroemia maxima examined in Managua, Nicaragua, and Ilopango and San Salvador, El Salvador, displayed all combinations of flower size and color, as well as anther and pollen color found in the two Puntarenas types. Stem color here varied independently as well, being either yellow-green or red- dish. In one Managua population, some plants were also prostrate with smaller leaves, and the others were decumbent with larger leaves, additional characters that appeared to vary independently. This same population yielded individuals with yellow anthers and pollen and with flowers which had a few red pollen grains on their stigmas. Others possessed flowers with red anthers and pol- len, and with a few yellow grains on their stigmas. This information THE GENUS KALLSTROEMIA 105 suggests that these characters are under simple genetic control. Further evidence in support of this conclusion, at least for anther and pollen color, is provided by greenhouse plantings of the prog- eny of Porter 1489, an individual of K. maxima from Mazatlan, Sinaloa, with red-orange anthers and pollen. Some of the progeny plants had red-orange anthers and pollen, as in the parent, others had yellow anthers and pollen. Another variation in flower color in this species is found in some populations in Guerrero and Michoacan. Here, the petals are proximally cream with a red spot at the base. Specimens with this red spot also have red anthers and pollen. As mentioned above, there is some variation in this species with respect to fruit pubescence. Classically, the presence of a glabrous fruit has been used as the key character for the recognition of Kallstroemia maxima. This is true for the majority of individuals, but there are exceptions. Specimens with a varying pattern of strigose fruit pubescence have been found at scattered localities throughout the range of the species, some fruits being strigose only at the base, but others across the abaxial surfaces of the mericarps to the base of the style. The only area where the fruit pubescence presents a more consistent pattern is in southwestern Mexico where K. maxima overlaps with K. rosei. The sepals of individuals of K. maxima in this region also vary toward those of K. rosei. They extend further beyond the mature mericarps and the margins are more involute than is true for specimens from other parts of the species range. This variation possibly is due to the introgression of genes from K. rosei. Despite the great range of variation in certain morphological characters in Kallstroemia maxima, it appears best not to give formal taxonomic recognition to the variants. The evidence in- dicates that they have a simple genetic basis, and there are no established ecological or geographical correlations present. More information, particularly of a cytogenetical nature, may lead to a more precise interpretation of the variability present. RELATIONSHIPS. This species is most closely related to Kall- stroemia pubescens and K. rosei. A discussion of the three species will be found above. Millspaugh (1916, p. 428), in a discussion of Tribulus alacra- nensis, a species supposedly endemic to the Alacran Shoals off the northern coast of Yucatan, Mexico, wrote of its “probable 106 DUNCAN M. PORTER parent T. maximus [= Kallstroemia maxima].” This undoubtedly was a slip of the pen, as he earlier ( Millspaugh, 1900) indicated T. alacranensis as being a close relative of T. cistoides. It is prob- ably conspecific with the latter, although a recent survey of the flora of these small islands (Bonet & Rzedowski, 1962) recognized T. alacranensis as a distinct species. However, T. alacranensis has no closer affinities to Kallstroemia than does any other species of Tribulus. Kallstroemia maxima K. pubescens? As has been indicated in the introductory material, under “Hybridization,” there are a number of collections of the genus from Colombia and Venezuela which appear to be morphologi- cally intermediate between Kallstroemia maxima and K. pubes- cens (Map 2). Comparative morphology suggests that these specimens may be the result of hybridization between the species indicated above, but there is no genetical evidence that this is the case. Until this becomes available, either through further field studies or crossing experiments, it is thought best to consider these specimens only as putative hybrids. SPECIMENS EXAMINED. COLOMBIA. LOCALITY UNKNOWN: Magda- ena, 600 m, Triana, 1851-1857 (BM). ATLANTICO: Barranquilla, Bro. US). HUILA: talus at base of dry eroded river bluffs, Rio AmbicA just above confluence with Rio Cabrera, F, osberg 19334 (COL, US). VENEZUELA. TRUJILLO: La Concepcién, 2500 ft, Reed 1005 in part (US). 2. Kallstroemia rosei Rydb. in Vail & Rydb., N. Amer. Fl. 25:113. 1910 TYPE: Mexico, Morelos: near Yautepec, 27 August 1903, J. N. Rose ¢ Jos. H. Painter 6562 (US, holotype; NY, isotype). THE GENUS KALLSTROEMIA 107 hirsute, veins and margins sericeous, 12-26 mm long, mm niet terminal pair largest; peduncles usually shorter than leaves, thickened distally, 2-5 cm long, more or less curved in fruit; flowers pentamerous, 2-3.5 cm in diameter; sepals pea ovate, 6-10 mm long, 2-3 mm wide, hirsute and e a mm wide, marcescent; stamens as long as style; anthers ovoid, rarely linear, ca. 1 mm in diameter, they and pollen red-orange, rarely yellow; ovary conical, 1-2 mm high, what conical and hirsute; mericarps 4 mm high, abaxially tubercled and cross-ridged, sides slightly pitted, adaxial edge angled. Fig. 2a, 2b. Map. 3. FLOWERING DATES. Mainly from June through September, fol- lowing the summer rains, but occasionally flowering until March. DISTRIBUTION AND HABITAT. Disturbed areas in the pine-oak forests of the mountains of northeastern, central, and southern Mexico, and occasionally spreading to lower elevations (Map 3). Found from 200 to 3150 m, mainly above about 1000 m. Sympatric with Kallstroemia parviflora to the north and K. maxima to the southwest, and slightly overlapping with K. californica, K. grandi- flora, K. hirsutissima, and K. pubescens in parts of its range. DISTINGUISHING cHARACTERISTICS. Kallstroemia rosei may be recognized by the combination of its obovate leaves, usually three pairs of leaflets, flowers 2-34 cm in diameter, hirsute and strigose sepals which spread from the base of the mature fruit and curve upward, sharply involute sepal margins making the sepals appear linear or linear-lanceolate, usually white petals, usually red-orange anthers and pollen, conical ovary, strigose fruit, ring of white hirsute pubescence at the base of the beak, the latter being about twice as long as the fruit body, and a capitate obscurely ten-lobed stigma. The only other species from the same area with which it is likely to be confused is Kallstroemia maxima. The latter is easily distinguished from K. rosei by its flowers of from 7-25 mm in diameter, hirsute sepals which clasp the base of the mature fruit, only their scarious margins becoming involute, and usually gla- brous ovaries and fruits. In those rare individuals of K. maxima with pubescent ovaries and fruits, these organs are sparingly 108 DUNCAN M. PORTER strigose. Kallstroemia maxima tends also to be smaller in overall plant size and less decumbent than K. rosei. In areas where the two overlap in distribution, petal color is white in K. rosei and yellow to orange in K. maxima. REPRESENTATIVE Soup EXAMINED, MEXICO. DURANGO: Trancas Canyon, ca. 7 m of Chocolate, among limestone boulders, 1350 m Correll & [linen 2001 4 (LL). NUEVO LEON: Cerro del Obispado, along sad 1500 ft, Lacds 36 (F); Son 1800 ft, Fisher 41 in part (CAS, S, F ). TAMAULIPAS: 5 km S of Hoja Verde, up arroyo, Stanford, Lauber 2 Taylor 2219 (DS, GH, MO, NY, RSA Ade 4 mi S Jaumave, ditch bank, Stanford, Lauber ¢ Taylor 2283 (GH, N Y, US); mountain top 7 km SW of Miquihuana, forest floor of low vegetation i in forest of large pines, 3150 m, Stanford, Retherford & sat'y craft 917 (ARIZ, DS, GH, MO, NY). SAN LUIS POTOSI: 10 km S of Cardenas, nee 1100 m, Rzedowski 4588 (TEX); Rio Verde, Piet 3 (F, GH, MO, NY, US). AGUASCALIENTES: 43 W of Aguascalientes, gentle S slope in xeric matorral, 2045 m, Det- ling 8737 (MICH); 9 mi E of Aguascalientes toward Ojuelos, brush-covered hills, 2000 m, McVaugh 16627 iaricaerre fs JALISCO: Jaday, Davis, 6 July 1959 (TEX); La Palma, M. E. Jones 109 (MO, MSC, POM, US). GUANA- H, M barren Jan : at “hillside. akg Painter & Rose 9617 (one HIDALGO: Jacala, wooded untain ravin , 4500 ft, Chase 7200 (F); Zimapan, Coulter 780 in part (GH. NY, PH). MICHOACAN: ca. 7 mi N of Ciudad Altamirano, Porter 1373 (DS, GH, MEXU); Coalcoman, Ilano, 1000 m, Hinton 13981 (GH, — 13050 (ARIZ, myo LL, MICH, NY, TEX, US). pntemagre Km between Axochiapan and fetes dione Hest fill at bpadlide Porter 1457 (DS, ‘CH, MEXU); 5 mi NW of Tehuacan toward Puebla, edge of highway, P O ‘ . 5789 (GH, LL, NY, PH, US); 10 mi Ww of a toward Teloloapan, road- MO, US). OAXACA: Cuicatlin, Pg; . C. Smith 494 (GH): wear Oaxaca, 1550 m, Conzatti 1832 CF GH, MEXU). CHIAPAS: Tuxtla Gutiérrez, vacant lot, 1800 ft, Breedlove 10619 (DS, GH). VARIATION. Fruit pubescence in Kallstroemia rosei varies from dense to sparse. Lightly pubescent fruits appear most commonly in the area south of the volcanic cordillera of south-central Mexico where this species is sympatric with K. maxima. This variation in fruit pubescence may be due to the introgression of genes from K. maxima. There is also some evidence that older fruits tend to be less pubescent than younger ones because of the loss of trichomes. RELATIONSHIPS. Kallstroemia rosei is most closely related to K. maxima. A discussion of their differences will be found above. THE GENUS KALLSTROEMIA 109 3. Kallstroemia pubescens (G. Don) Dandy in Keay, Kew Bull. :138. 1955 Tribulus ne G. Don, Gen. Syst. 1:769. akg TYPE; Cape Coast [Accra, Ghana], G. Don s. n. (BM, pc not s Kallstroemia minor Hook. "bd n Hook., Niger FI. 269. 1849. nom. superfl. Based on Tribulus i eeoomgee G. Dib, cited as a synonym Tribu 4 Ne ag var. minor Oliver, Fl. Trop. Afr. 1:284. 1868. Tyre: Cape C i Vo el. Ka Niesidida caribaea Rydb. - Sa es be Ae N. Amer. FI. 25:111. 1910. TYPE: West Indies, Montserrat creeping in seg patch, fis. yellow; 5 February 190 907, J. A Shofer 388° (ss Saletrie isotypes ). The : var. caribaea (Ryd "hg in ‘Vail & Rydb.) m Ballet Gurnee Rydb. in i : Rydb., op. cit. 114. 1910. TYPE: Mexico, arr 0a: Rosario; 22 July 7, J. N. Rose 1829 (ny, holotype; MEXU, MO, iso ual; bo prostrate to decumbent, to 1 m or more long, sparsely to densely hirsute and sericeous with apically-directed or rarely retrorse fine white se wae a mm long, 1-2 m glbnionss eaves obovate, 1-6 rf in fruit variable; rae pentamerous, Te the mm in omega! se 4 slisibsaiooe: heak 5-8 met ee ca. as ee as “fruit body, s sie : maior — base he eensioak a 3-4 mm high, ca FLOWERING DATES. Apparently flowering throughout the year whenever sufficient moisture is available for seed germination mit plant growth ON AND HABITAT. The Lesser Antilles, Puerto Rico, wa Jamaica; across northern South America and north through Central America to Yucatan on the east and Sinaloa on the west 110 DUNCAN M. PORTER coast of Mexico; south through Colombia and Ecuador to northern Peru (Maps 4 and 5). Introduced into Florida, Ghana and Nigeria, Africa (Keay, 1955), and West Bengal, India (Bennet, 1965). Disturbed areas from sea level to 1400 m, most common at lower elevations. Sympatric with Kallstroemia hintonii and K. standleyji, and over most of its range with K. maxima. Extending into the ranges of K. curta in the Caribbean and K. californica, K. grandi- flora, and K. rosei in western Mexico. ics. Kallstroemia pubescens may be recognized by its combination of obovate leaves, usually three pairs of leaflets, usually white flowers 9-15 mm in diameter, hispid- ulous sepals spreading from the base of the mature fruit, the sepals appearing linear or linear-lanceolate through the sepal margins becoming sharply involute, usually red-orange anthers and pollen, pyramidal ovary, densely appressed short-pilose fruit, with the beak about as long as the fruit body, and a capitate obscurely ten-lobed stigma. Kallstroemia maxima is the only species from the same area with which K. pubescens is likely to be confused. The two are readily distinguishable to the naked eye because of fruit and sepal differences. In K. maxima, the sepals are hirsute, clasp the mature mericarps, and only their scarious margins become involute; the fruit is usually glabrous, rarely being strigose. In localities where the two species grow together, the herbage of K. pubescens tends to be lighter in color and less succulent than that of K. maxima. In such areas, the petals of K. pubescens invariably are white, while those of K. maxima are yellow to orange. ENTATIVE SPECIMENS EXAMINED, vane a eer FLORIDA. F; toring Co.: Apalachicola, Chapman s. n. (MO), 40 re A a paige Rosario, Rose 1830 in part NY} ARIT Jestis Maria, dry woodland, Feddema 1329 (eG JALISCO: Bolafios, Rose 3080 in eal (NY). MICHOACAN: El] Capire, 15 mi SSW of Apat- zingan, moist open, often by standing water, Leavenworth 439 (ARIZ, F, GH, MICH. MO, NY); pass grassy hill, 350 m, Hinton 12097 (DS, GH, MICH, NY, US). GUERRERO: Atoyac, shrubby plain, eg 14543 _G ot a NY, PH, US); Placeres to Pinzon Morado, Ilano, 400 m, Hinton 9119 (ARIZ, GH, LL, NY, US). OAXACA: Puerto aa, Orcutt 5017, 5029 (DS); 4 km NNE of Tehuantepec, gravelly roadside, flat grazed areas, King 1315 (MICH, NY, SMU, TEX, UC, US). CHIAPAS: 8 mi E of Cintalapa on Highway 190, wooded slope, 2200 ft, Breedlove 10315 (DS, GH). YUCATAN: Valladolid, Steere 1693 (F, mpi MICH). QUIN- TANA ROO: Chichankanab, Gaumer 1570 in part (BM GUATEMALA. ZACAPA: near coven damp field, ca, 200 m, Standley 73599 (F, US). THE GENUS KALLSTROEMIA 111 oe arr sila LA PAZ: Bosque la Herradura, 100 m, Lagos, 28 Sept Lit HONDURAS. SANTA BARBARA: San Pedro Sula, 1000 ft, Thieme 5170 (F, GH, US). COMAYAGUA: W of Comayagua near El Tala dro, savannahs and roadside, 650 m, Molina R. 14287 (F). VALLE: San Lorenzo, 20 m 3449 NICARAGUA. CHINANDEGA: E base of Volcin Cosegiiina, ae ll 10269 (CAS). MATAGALPA: just N of Las Maduras, rocky roadside em- pen henens Porter 1215 (GH). MANAGUA: E of Tipitapa toward ae m 43, edge of highway, Porter 1213 (DS, GH, IJ). MASAYA: pee Baker 211 (ARIZ, POM), 665 (US). CHONTALES: near Juigalpa, wa: ground, ca. 160 m Spey 9316 COSTA RICA. GUA ACASTE: Catalina, forest, Stork 2769 (F, MICH). PUNTARENAS: Mata . Limon, along railroad track, 7 m, Porter 1187 (CR, GH). PANAMA. PANAMA: near beach at Nueva Gorgona, Duke 4499 (MO). JAMAICA. ST. ANDREW: St. Benedict’s S School, E of Harbour View, PUERTO RICO. GUAYAMA: near Salinas. sandy plain, Britton, Britton ¢é> Brown 6045 (NY). VIRGIN ISLANDS. ST. THOMAS: ene road, Eggers, June 1887 (US). TORTOLA: Experiment Station, waste places, F ishlock 131A (NY). f Proctor 19029 (BM, IJ). GUADELOUPE: Viux Habitants, 10 m, Ques stel 2167 (US). WINDWARD ISLANDS. bath tan oi eonpeente Vert, dry thicket, 350 m, Stehlé ¢ Stehlé 4784 (US). ST. VINCENT: sandy soil near Poss i i ns VENEZU OATEGUI: Guanta, roadside, ca. sea level, Potter 5149 (GH, US). ‘NUEVA ESPARTA: El Valle, mot sae L., Miller & John- ag Be ige-agi Asplund 5063 (CAS, F, NY, US). LOJA: Rio Guayabas 5 Catama ee dry brushy Giler HE! (COL, US). ERU. PIURA: Parifias Valley, Haught F-51 (F), 147 (F, GH, NY, PH, us). CHANA: Accra, near beach, Enti, 31 May 1964 (GH). 112 DUNCAN M. PORTER Two specimens of Kallstroemia pubescens have been seen that were supposedly collected in the southwestern United States. These are “Walter H. Evans, 23 June 1891, Ft. Hancock, Texas” (Mo) and “Dr. Woodhouse, 29 Sept. 1851. N. M. Camp No. 6, Little Colorado” (pH), the latter from Apache County, Arizona. These collections are sufficiently removed from the known range of the species, which is essentially tropical, to cast doubt on the authenticity of the label data. The problem of the wrong label being applied to a specimen also has been encountered in K. grandiflora and K. maxima. A mixed collection of Kallstroemia pubescens and K. maxima from Georgia, Beyrich s. n. (mo), probably is a product of a mis- applied or lost label. A collection of this species from Florida, Chapman s.n. (Mo), is labeled “Cult.” COMMON NAMES. Most of the common names applied to Kall- stroemia pubescens are identical to those used in the same area to designate the superficially very similar K. maxima. Common names of which I am aware are Abrojo (Colombia); Angglo Boobo (Bonaire, Curagao); Anglo Bobo (Aruba, Bonaire, Curagao ); Cocli (Colombia); Golondrina (Costa Rica); Huistolo- huetzli (Guerrero, Mexico); Pourpier Batard (Guadeloupe, Mar- tinique ); Pourpier Jaune Courant (Martinique); Pourpier Marron (Guadeloupe); Verdolaga (Colombia, El Salvador); and Verdo- laguilla (Nayarit, Mexico). In addition, Irvine (1930, p. 419) reports that in Ghana the plant is called Akwamfanu, and that “the vernacular name comes from ‘Okwan afanu,’ which means ‘on both sides of the road,’ probably because it is a common weed along bush paths.” TAXONOMY. The name Kallstroemia longipes has been given to somewhat larger than average specimens of K. pubescens from southwestern Mexico. However, specimens at this extreme in variation are found scattered throughout the range of K. pube- scens and probably are due to optimum growth conditions. As has been indicated above, this species was first described from Africa, 80 years before being recognized as distinct from K. maxima in the West Indies, where it is indigenous. It undoubtedly was introduced into West Africa very early, as is attested by its wide use in the native materia medica (cf., Irvine, 1930). Intro- duction probably came about through the activities of the slave THE GENUS KALLSTROEMIA 113 trade between West Africa and the West Indies, which began in the first half of the sixteenth century (Penrose, 1952). VARIATION. This species is rather constant in its morphological characters, especially for one of such a wide geographical range, except for the quantitative variation in size mentioned above. Almost all specimens seen had stem trichomes that were antrorse, but in Haught F-161 (F) and Haught 262 (NY) from Peru, these trichomes were retrorse, similar to those in K. peninsularis. The anther and pollen color in most populations is red, but popula- tions in which it is yellow occasionally are found. RELATIONSHIPS. Kallstroemia pubescens is most closely related on the one hand to K. maxima, and on the other to the southern South American K. tucumanensis. Morphological comparison of K. maxima and K. pubescens will be found above. The initial recognition of the close relationship between Kall- stroemia pubescens and K. tucumanensis was by Svenson (1946b ), who considered that specimens of the former from Ecuador and Peru were conspecific with those of the latter from Argentina. However, K. tucumanensis may be easily distinguished from K. pubescens by its usually two to three pairs of leaflets, pale yellow to yellow-orange flowers 4-8 mm in diameter, yellow anthers and pollen, ovoid ovary, strigose fruit, and capitate ten-ridged stigma. 4. Kallstroemia tucumanensis Desc., O’Don. & Lourt., Lilloa 218. 1939 TYPE: Argentina, Tucuman: Tapia to Vipos, elev. 750 m; 4 February 1939, C. A. O’Donell ¢> A. Lourteig s. n. (LIL, holotype, not seen; Ds, F, GH, NY, UC, iso “A ; stems prostrate to decumbent, 1-6 dm long, hirsute and sericeous with apically-directed white trichomes; stipules 2.5-3 mm long, ca. 1 mm wide; leaves obovate, 3—-5.5 cm long, 15-3 cm wide; leaflets P nD e. 2 —l ide, ultimate usually largest; ——. shorter than subtending mm or curved in fruit; flowers pentamerous, 4-8 mm in diameter; sepals subulate, 4-5 mm long, 1-2 mm wide, ca. as long as petals, hispidu- lous with fine white trichomes of two lengths, longer than style in flower, spreading from base of mature fruit and little — than mericarps, margins ing sharply involute, persistent; petals pale yellow to yellow-orange, narrowly obovate, 3-5 mm long, 2-3 mm wide, marcescent; stamens as long 114 DUNCAN M. PORTER long, papillose; fruit ovoid, 5 mm in diameter, radia beak 2-3.5 mm long, stout, ie strigose to stigma base; mericar m high and 1 mm wide, abaxia ly m more or less tubercled tutntally istic ae aan slexiel! edge angled. Fig. 4a, 4b. Map 6 FLOWERING DATES. November through April following summer rains. DISTRIBUTION AND HABITAT. Semiarid southern Bolivia and northwestern Argentina (Map 6). Disturbed areas, sandy river- banks, railroad embankments, and roadsides from 420 to 1250 m. Sympatric over much of its range with Kallstroemia tribuloides. DISTINGUISHING CHARACTERISTICS, Kallstroemia tucumanensis is easily recognized by its combination of obovate leaves, usually two to three pairs of leaflets, pale yellow to yellow-orange flowers 4-8 mm in diameter, hispidulous sepals spreading from the base of the mature fruit and appearing linear or linear-lanceolate through the margins becoming sharply involute, yellow anthers and pollen, ovoid ovary, capitate ten-ridged stigma, and strigose fruit with a stout conical beak shorter than the fruit body. Kall- stroemia tribuloides, the only other species in the genus known from the same area as K. tucumanensis, is not likely to be confused with the latter. It differs in having elliptical leaves, three to six pairs of leaflets, orange flowers 14-2% cm in diameter, hirsute and strigose sepals clasping and almost entirely covering the mature mericarps, sepal margins not becoming involute, orange anthers and pollen, a conical ovary, an oblong ten-ridged stigma, and a glabrous fruit with a cylindrical beak as long or longer than the fruit body. IMENS EXAMINED. BOLIVIA. SANTA CRUZ: Cabezas, 420 m, Peredo 250 (A). Ly Villamontes, ges 4041 Termas, Legname 5 (CAS). CORDOBA: Km 969, Dept. Ischilin, Brizuela 897 (SMU). MENDOZA: Rancho de Tofora, 500 m, Ruiz Leal 9021 ARIZ). This species also has been reported from the Argentinean states of La Rioja sad hanes Rios (penacke. et al., 1939) and San Luis (Ruiz Leal, 1947). THE GENUS KALLSTROEMIA 115 TAXONOMY. Svenson (1946b) considered Kallstroemia tucuma- nensis to be conspecific with K. adscendens, but the two are distinct. The latter is endemic to the Galapagos Islands, Ecuador. RELATIONSHIPS. Kallstroemia tucumanensis is most closely related to the more northerly K. pubescens. The latter differs from K. tucumanensis in having mostly three pairs of leaflets, flowers 9-15 mm in diameter, obovate petals 6-11 mm long and 5-8 mm wide that are usually white, anthers and pollen only occasionally yellow, a pyramidal ovary, a densely appressed short-pilose fruit with a beak 5-8 mm long, and an obscurely ten-lobed stigma. 5. Kallstroemia hirsutissima Vail in Small, Fl. SE. U. S. 670. 1903 type: New Mexico, Dona Ana Co.: plains S White Sands, elev. 4200 ft, 28 August 1897, E. O. Wooton 564 (ny, holotype; MO, NY, US, isotypes). ; ostrate, 1.5-7 dm long, copiously sericeous an hirsute Annual; stems pr ( with white or gray apically-directed trichomes, forming a dense carpet- like mat; stipules 3-6 mm long, ca. 1 mm wide; leaves obovate, 1-4 cm ts 3-4 ong, m wide, copiously and conspicuously ubescent; pairs, broadly elliptical to oblong-ovate or broadly ovate, densely hirsute and conspicuously ciliate, veins and mar, ins sericeous, 12-19 mm long, mm wide, inal pair largest; peduncles shorter than subtending leaves, thickened distally, 5-12 mm long, i : ers penta: erous, less than 1 cm in diameter; sepals subulate, 2.5-4 mm long, ca. mm wide, hirsute and sparingly strigose, in flower ca. as long as style, in fruit clasping mature meric and ca. 1/2 as long as them, only scarious margins becoming involute, persistent; petals yellow, fading white or orange, obovate, 2-4 mm long, ca. 1.9 mm wide, marcescent; stamens as long as style; anthers ovoid, less than 1 mm in diameter, they and pollen ye ef > above, base broadly conical; prominently tubercled, sides p FLOWERING DATES. Following the summer rains from June to October, but mainly from July to September. DISTRIBUTION AND HABITAT. Chihuahuan Desert and adjacent areas of semiarid grassland from southeastern Arizona to Tamau- lipas and southern Texas (Map 7). Found from sea level to about 1700 m, mainly at higher elevations. Sympatric with Kallstroemia californica, K. grandiflora, K. parviflora, and K. perannans, and slightly overlapping with K. maxima and K. rosei in Nuevo Leon and Tamaulipas DISTINGUISHING cHARACTERISTICS. Kallstroemia hirsutissima has 116 DUNCAN M. PORTER copiously pubescent stems which form a dense carpet-like mat, obovate leaves, three to four pairs of conspicuously ciliate leaflets, yellow flowers less than 1 cm in diameter, hirsute and sparingly strigose sepals which clasp the mature mericarps, only their scarious margins becoming involute, a stout broadly conical very short style that is 4% as long as the ovary, the more or less clavate ten-ridged stigma appearing almost sessile on the ovary, a broadly ovoid strigillose fruit 4-5 mm high and 6-8 wide, and a conical beak 14 mm long, hirsute with a ring of short white trichomes. K. hirsutissima is unlikely to be confused with any other species of the genus growing in the same area. ENS EXAMINED. UNITED ST tags diay og Pima Co.: Tucson, ruz Co. ie creek bottom 6 mi. LE of ates sray-brown Siok areo ik SI inners 30833 (SMU). Bexar Co.: San Antonio, Ball 908 ee Cook, 1906 (LL), porte 1704 (MO), Schulz 783 (US). Duval Co.: Diego, Croft 198 NY). Cameron Co.: Brownsville, open grounds and i fields, clay soil, 10 m, Runyon 1857 (oe Santa Ana National Wildlife Refuge, gravel pile, Fleetwood 3839 (TE ME OCALITY UNKNOWN: Limpia Valley, Edwards 78 in part (MICH). CHIHUAHUA: 10 km. E of Barre eal, dry sandy hillsides, Stewart 662 (GH); a mi. SE of Pare ie 4500 ft, Shreve 8874 ( ARIZ. Cp. be- oO MICH US); Chihu aha, LeSeuer 353 (CH, SMU); hills and plains near Chihuahua, Pringle 679 (BM, CAS, F, MICH, NY, PH, RSA, US); 5 mi. E of Ciudad oes ca. 4500 ft, S. S. White 2143 (GH, MICH); Susskind: LeSeuer 253 (F, TEX); broad soles 25 km. NW of Jaco toward Victoria, silty flat, Stewart 678 (GH); 5.5 mi, S of Ojinaga toward Alamos Chapo, 0 “ese from saline shales, Johnston 8004 (GH). COAHUILA: arroyo ciate Villa Garcias SW of Saltillo, ca. 5500 ft, Bell ¢+ Duke 16578 : MO): age UC); is valley floor 10-15 km. E of San Antonio toward Buenavista, savanetta, Johnston, 31 ‘ions 1941 (GH); 5 mi. NW of Zenzontle toward THE GENUS KALLSTROEMIA 117 San José, sabaneta, Johnston & Muller 971 (GH). NUEVO LEON: Monter- rey, Edwards s. n. (NY); near Monterrey, Edwards 140 in part (MICH); desert or mi. W of Monterrey, along arroyo, Waterfall & Wallis 13182 (SMU); along highway 40 mi. S of Monterrey, Drushel 9327 (NY). TAMAULIPAS: 0.5 mi. S of Htedacleal Stanford, Lauber & Taylor 2172 (GH, NY, US); near Victoria, ca. 320 m, Palmer — in part (MO). SAN LUIS POTOSI: Las Palmas, Rose & Hough 4877 COMMON NAME. Carpetweed. RELATIONSHIPS. Kallstroemia hirsutissima is most closely related to K. curta, a species of Hispaniola and the southern islands of the Netherlands Antilles. The latter differs in having usually three pairs of leaflets, the sepals spreading from the base of the mature fruit, and their margins becoming sharply involute, white to yellow-orange petals, a style about as long as the ovary, and the ovoid fruit 4-5 mm in diameter with the strigose beak 14-2 mm long. 6. Kallstroemia curta Rydb. in Boldingh, Fl. Nederland. West-Ind. Eilanden 230. 1913 : West Indies, Curacao: rocky coastal hill, St. pe Fae! prostrate ibasttes 8 dm long; 20-27 March 1913, N. L. Britton & Shafer 3 is confirmed to be the vers otype. Kallstroemia incana Rydb. in Britt., Bull. Torr. Bot. Club 51:3. 1924, TYPE: West Indies, Dominican Republic: Barahona, sea level, flower yellow, July 1910, Fr. Miguel Fuertes 418 (NY, reared i GH, IJ, MO, US, iso ; rostrate, 2-3 dm (rarely to 1 m) long, hirsute and seri ith white apically-directed trichomes, usuall g a dense Cc -like mat; stipules 2-4 mm long, ca. m ; jhe os ebowath 1-4 cm long. wide, usually appearing grayish because of dense pubes- cence; leaflets 3( pairs, ovale: densely ‘appressed-hirsute, veins mar, oming glabrate, 9-15 mm long, 5-10 mm wide, ter- minal pair largest; peduncles shorter than leaves, 2-3 mm long in r, in 13 curved or straight; flowers pentamerous, less 1 cm in di sepals subulate, 2.5—4 mm long, 1-2 wide, hirsute and strigose, longer than style in flower, shorter th an reading i ming petals white to yellow-orange, elliptical to obovate, 3-4 mm long, ag stamens as long as style; anthers globose, much less ~ 1 mm in diameter * sens and pollen polio ovary ovoid, ca. 1 mm in diam sae sty . as long as ovary, stout, conical, strigose; caoas clavate ea ai 1 mm long, papillose; fruit ovoid, 4-5 mm in diameter, stri 1.5-2 mm long, stout, conical above, base widely ek strigose; mericarps 118 DUNCAN M. PORTER 3 mm high, ca. 1 mm wide, abaxially tubercled, sides pitted, adaxial edge angled. Fig. 6a, 6b. Map 8. FLOWERING DATES. Known to flower in March in Curacao and in July in Cuba, but flowering from January through October in Hispaniola. As in the other Caribbean species, seed germination, plant growth, and flowering probably take place at any time of the year following sufficient rainfall and appropriate temperatures. DISTRIBUTION AND HABITAT. Disturbed areas from sea level to 1300 m, mainly at lower elevations. Apparently native to Hispa- niola and introduced into Cuba and the Netherlands Antilles (Map 8). Sympatric with Kallstroemia maxima in Hispaniola and Cuba, and with K. pubescens in the Netherlands Antilles. DISTINGUISHING CHARACTERISTICS. Kallstroemia curta may be recognized by its stems forming a dense carpet-like mat, which appears grayish because of the dense pubescence, obovate leaves, usually three pairs of densely pubescent leaflets, white to yellow- orange flowers less than 1 cm in diameter, hirsute and strigose sepals which spread from the base of the mature fruit and have sharply involute margins, clavate ten-ridged stigma, and ovoid strigillose fruit with a conical beak 14-2 mm long. This species is apt to be confused with Kallstroemia pubescens in the southern- most part of its range. The latter may be distinguished by its more upright open habit, peduncles 1-34 cm long in fruit, usually white flowers 9-15 mm in diameter, hispidulous sepals, pyramidal ovary, capitate obscurely ten-lobed stigma, and densely appressed short-pilose fruit with a beak 5-8 mm long. SPECIMENS EXAMINED. CUBA. ORIENTE: Estacién Naval de Caimanera, Bro. Hioram 3958 (US). HAI rd Ekman H4038 (US). ARTIBONITE: Cap St. Marc, railroad track near lighthouse, Ekman H6652 (A); road SE of Gros Morne, ca. m, Leo 9972 (GH, NY, UC, US); near Ennery, Puilboreare road, Leonard 8813 (GH, NY, UC); Hinche, Savane-Papaye, 225 m, Ekman H6011 (IJ, US). Oo : Port-au-Prince, Plaine de Léogane, Buch 1173 (IJ). MINICAN REPUBLIC. SANTIAGO: Hato del Yaque, fields, Ekman H15981 (US); Valverde, Uniola savannah, ca. 100 m, Ekman H13107 (US). A: San Juan, fields, Ekman H13395 (A, US). BARAHONA: Rincon, 25 m, Fr. Fuertes 1352 (NY, US); near Rincon, 1300 m, Fr. Fuertes 1353 i et Salina, decomposed salt rock, Howard ¢> Howard 8410 (GH, CURACAO. Without locality, Read s.n. (PH). THE GENUS KALLSTROEMIA 119 Boldingh (1914) reports Kallstroemia curta from the island of Aruba, and Arnoldo (1964) records it from this island and also from Bonaire, but the only specimens I have seen from the southern Caribbean are those from Curacao cited above. COMMON NAMES. No common names have been recorded for this species in Cuba or Hispaniola. However, in Aruba, Bonaire, and Curacao it is known by the same names as is Kallstroemia pubescens: Angglo Boobo or Anglo Bobo. TAXONOMY. In publishing Kallstroemia incana, Rydberg indi- cated its affinities with K. curta, but stated that it differed in being “more canescent, more branched, with shorter internodes and smaller leaves, and the beak different, not at all swollen.” Except for the beak, these differences all are of vegetative char- acters that prove to be very plastic in all species of the genus where environmental conditions vary. Upon examination of the specimens cited above, all differences given by Rydberg and others, both of a vegetative and floral nature, overlap between the populations in Hispaniola and Cuba and those from Curagao. The more northerly collections tend to be more pubescent than those from Curacao, but this single difference hardly makes them worthy of taxonomic recognition, even at the subspecific level. RELATIONSHIPS, Kallstroemia curta is most closely related to K. hirsutissima, a species of northern Mexico and the southwest- ern United States. Kallstroemia hirsutissima differs in having three to four pairs of leaflets, hirsute and sparingly strigose sepals which clasp the mature mericarps, with only their scarious margins be- coming involute, yellow petals, a very short stout broadly conical style that is 4% as long as the ovary, the stigma appearing to be almost sessile on the ovary, and a broadly ovoid strigillose fruit that is 4-5 mm high and 6-8 wide, with a 14 mm long beak which is hirsute with a ring of short white trichomes. 7. Kallstroemia adscendens (Anderss.) Robins., Proc. Amer. Acad. 38:156. 190 Tribulus adscendens Anderss., Svensk. Vet-akad. Handl. 1853:245. 1854. type: Ecuador, Galdpagos Islands: “Hab. locis inosis, siccis regionis inferioris insularum Chatham et Charles . N. J. Andersson s. n. (holo’ resumably at s, not seen; GH, iso ‘ THeoal nected ey endens Rader). Anderss., op. cit. 1857: 107. 1861. I follow Rose (1892) and Robinson (1902) in assuming that Anders- son intended to make this combination, although his citation might lead one to the conclusion that he considered T. adscendens to be a synonym of T. 120 DUNCAN M. PORTER maximus. This is a ess assumption, as Andersson Jater mainte referred to this taxon as “T. maximus var. A.”, A. indicating “of An n.” Annual; stems setasteate to decumbent, to several dm aes sericeous and hieeins with apically-directed white trichomes; stipules 3-4 mm long, ca. mm w wide; leaves a ata to ca. 2 cm lon and 1 cm Lot leaflets 9-3 ae less than 1 cm in diameter; seal subulate, 3-3.5 mm long, ca. m wide, littl er petals, hirsute and strigose, longer than n er but not extending beyond tops o ture mari s in fruit, ing persistent oie yellow, obovate, ca. 4 mm long, 2-3 mm wide, marcescent; m sta ong as style; anthers globose, much less than 1 mm in n diameter, they fad voles yellow; ovary ovoid, ca. 1.5 mm in diameter, strigose; style mm long, stout, conical, strigose; stigma clavate, ‘L0-ri dged, less than 1 mm long, papillose; fruit ovoi , 3-4 mm in diameter, strigose; eak ca. 2mm we a. 1/2 as long as fruit body, conical, strigose; mericarps ca. 3 mm high and 1 mm wide, abaxial See and tubercled, sides pitted, adaxial pis angled. Fig. 7a, 7b, Map 9 FLOWERING DATES. Known to flower from April through June, during the last half of the rainy season. DISTRIBUTION AND HABITAT. Endemic to the Galdpagos Islands, Ecuador (Map 9). Found on the beaches and lower slopes of the arid coastal zone of the islands. DISTINGUISHING CHARACTERISTICS. Kallstroemia adscendens may be recognized by its elliptical leaves, two to three pairs of leaflets, fruiting peduncles longer than the subtending leaves, yellow flowers less than 1 cm in diameter, hirsute and strigose sepals spreading from the base of the mature fruit, with the margins becoming sharply involute, and tubercled strigose fruit with the beak about % as long as the fruit body. SPECIMENS EXAMINED. LOCALITY UNKNOWN. Andersson s. n. (NY), 1852 (MO). BARRINGTON ISLAND. Bahia de Barrington, NE part of island, stony ground, ca. 325 ft, Snow 113 (DS). Along intermittent water course ee mi inland to SW from NE comer of island, Wiggins & Porter 587 AS). CHAMPION ISLAND. Without locality, Wiggins & Porter 513 (CAS). CHARLES ISLAND. he Office Bay, beach and environs at E end, Wiggins & Porter 558 (CAS CHATHAM ISLAND. Punti Pitt, Snow 244 pine b Along road from Wreck Bay to El Progreso, Wiggins & Porter ud (CAS). DUNCAN ISLAND. Without locality, Agassiz, 2 Apr 1891 (GH, US). Lower slopes, middle eastern part of island, Hosted 9819 (CAS, GH). tT THE GENUS KALLSTROEMIA 121 GARDNER ISLAND. Without locality, Snodgrass & por. 615 (DS, . Common over much of island, Wiggins & Porter 473 (C HOOD ISLAND. Without locality, Snodgrass & Heller 758 (GH). On beach, Gardner Bay, Howell 8653 (CAS). Along S side of Punta Suarez, Wiggins & Porter 489 (CAS). W end inland from Punta Suarez, Wiggins Porter 457 (CAS) VARIATION. Although Andersson described Kallstroemia ad- scendens as having a five-carpellate fruit with two single-seeded locules per carpel, examination of available material shows this species to be a typical Kallstroemia with ten one-seeded meri- carps. RELATIONSHIPS. Robinson (1902) was the first to suggest the close relationship of Kallstroemia adscendens and the North American K. californica (as K. brachystylis). The latter may be distinguished from K. adscendens by its hirsute and strigose stems, three to seven pairs of leaflets, fruiting peduncles shorter than the subtending leaves, usually deciduous sepals, strigillose fruit with prominent tubercles that may reach 1% mm in length, and cylin- drical beak that is little shorter than the fruit. 8. Kallstroemia californica (S. Wats.) Vail, Bull. Torr. Bot. Club 22:230. 1 Tribulus californicus 5; eas pit Proc. Amer. Acad. 11:125. 1876. TYPE exico, Si. California: side of the peninsula, Pil Palmer s. n. (cu, holotype). As i indicted ‘aleve (Porter, 1963), the type probably was collected in Jan 1 February, 1870, in southern Baja California. ee Drachystylis Vail, Bull. Torr. Bot. Club 24:206. 1897. TyPE: ew | a Co.: a near Las Cruces, alt. 3900, 12 August 1895, E. ‘0. Woo n. (NY, holotype; GH, isotype ). ve etibulus brdenipieiiis (Vail) Robins. in Gray, Syn. Fl. N. Amer. 1:354. emia californica var. brachystylis (Vail) Kearn. & Peeb., Jour. "Kallstro Wash. Acad. Sci. 29:485. 1939. ; stems prostrate to decumbent, 1-6.5 dm long, hirsute and nh, with apically-directed white trichomes, becoming glabrate; stipules 1.5-5 mm long, ca. 1 mm wide; leaves elliptical to occasi ionally obovate, 1.5-6 cm P leaves, thickened distally, to 15 mm long in flower, in fruit diameter; sepals lanceolate, 2—4 L wide, igose or ir- s strigi : sete involute, usually decidyous, if of mature mericarps; petals yellow, drying white or orange, obovate, 4-6 mm long, 2.5-3 mm wide, marcescent; stamens as long as style; anthers ovoid, 192 DUNCAN M. PORTER less than 1 mm in diameter, they and pollen yellow; ovary ovoid, ca. 1 mm in diameter, pubescent; style shorter than ovary, stout, conical, strigillose; stigma clavate, 10-ridged, less than 1 mm long, papillose; fruit ovoid, 3-5 mm wide including tubercles, to 4 mm high, strigillose; beak 2-4 mm long, shorter than fruit body, cylindrical, base conical, glabrous or base sparingly trigillose; mericarps ca. 3 mm high an mm wide, abaxially with 4-5 blunt oblong tubercles that may reach 1.5 mm long, tubercles becoming more prominent as fruits mature, sides pitted or smooth, adaxial edge angled. Fig. 8a, 8b. Map 10. FLOWERING DATES. Following summer rains (mainly July through October) through most of the range, but occasionally beginning in March in Texas, and August through March (follow- ing both fall and winter rains) in Baja California. DISTRIBUTION AND HABITAT. Flat sandy and disturbed areas of the Sonoran Desert across the northern Chihuahuan Desert to the semiarid grasslands of Tamaulipas and southern Texas; also along the west coast of Mexico to southern Sinaloa and the Tres Marias Islands, and extending into northern Arizona and southern Baja California (Map 10). Found from sea level to about 1600 m, mainly at lower elevations. Sympatric with Kallstroemia grandi- flora, K. hirsutissima, K. parviflora, K. peninsularis, and K. peren- nans, and slightly overlapping in the southwest with K. maxima and K. pubescens and in the southeast with K. maxima and K. rosei. CHA ics. Kallstroemia californica is easily recognized by the combination of its hirsute and strigose stems, usually elliptical leaves, three to seven pairs of leaflets, fruiting peduncles shorter than the subtending leaves, yellow flowers less than one centimeter in diameter, usually deciduous sepals, strigil- lose fruit with prominent tubercles that may reach 1% mm in length, and a cylindrical beak that is little shorter than the fruit body. Although there may be some overlap in these characteristics with other species in the same geographical area, in combination they readily distinguish Kallstroemia californica from its congen- ers. REPRESENTATIVE FORNIA. San Bernardino Co.: Conrise Valley, sands, Jaeger, 15 Sept 1925 (POM); 8 mi W of Ludlow, Ferris 1326 (DS). Riverside Co.: hay fields, Jones, 7 Sept 1925 (DS). San Diego Co.: SW part of Colorado Desert, 4002 , THE GENUS KALLSTROEMIA 123 Coconino Co.: Havasupai re fields and waste places, pe 7065 er 1.5 mi below 1608 (NY). Yuma Co.: near r Moha wk, slat; Rents & Kea (ARIZ, US); Yuma, mesas and domcaiien Thornber, 24 a 1912 (ARIZ, pad Maricopa Co.: Litchfield, Peebles, Harrison & Kearney 4525 (ARIZ). nal Co.: near Sect roadsides, Kearney 123 (US); Sacaton, Peebles 10507 (ARIZ, POM, US). Pima Co.: 4 mi W of Mission San Xavier, near shallow arroyo, Wiggins & Rollins 57 (ARIZ, DS, GH, MICH, MO, NY, US); Tucson, 2400 ft, Meise! 234 (ARIZ, DS, MO, NY, POM, UC). Graham Co.: Clifton, Davidson 1 7 (DS). Santa Cruz Co.: hills near Nogales, earne i : Cabez Eggleston 16262A (US). Dona Ana Co.: Mesilla Valley, ca. 3850 ft, Wooton & seri 3189 (ARIZ, DS, F), 27249 (WIS); Organ Mts., ice 422 (DS, MO, NY, POM, UC, US). Eddy Co.: sandhills near ing, Standley * 40387 (US). Notes El Paso Co.: desert near El Paso, Knobleoh 199 (MSC). aye oe between Nulo and Harris Siding, Ferris & Duncan 2449 in ( MO). "Presidio Co.: Presidio, Trelease 311 MO). Brewster ag near San Vicente, muddy ban of Rio Grande, Young, 26 Aug 1915 the X). Kerr Co.: Kerrville, Cook 20 (LL), 20A (LL, NY). Kinney Co.: mi E of Del Rio, San Antonio, alae 2541 in part (WIS). Lavaca Co.: Hallettsville, Fisher 109 (US). Atascosa Co.: 13.6 mi S of Jordanton, silty clay roadside, Shin- ners 16953 (SMU). La hg Co.: US Highway 81, 13 m i N of Encinal, orange-brown sand, Solis 56 (S SMU). Live Oak Co.: Choe West, sandy me Schiller 950 (US). San Patricio Co.: 7.5 mi S of Taft, sandy loam, B. Jones 491 (SMU). Aransas Co.: Aransas Refuge, Blakey 43 (GH). =i Co.: Laredo, Palmer 131 in art (F, MICH, NY). - mena Creek, saline soil, Correll & Tohats 19737 (LL). corr Co.: Kings- ville, dry neglected at in disturbed areas, Bogush 11845 (ARIZ, US). Zapata Co.: San Ygnac Tharp 3517 (TEX, US). Jim Hogg Co.: State repel y 359, 5 mi W - Hebronville, loose pale orange sand, Ramirez, Alva & McCart 8717 (SMU, TEX). a9 Co.: US Highway 83 below Falcon Dam, fine sandy silt, Garza Gong ; , TEX). ap sat Co.: Rio Grande Valley, Walker 67 poco LL. TEX, VG). R Willacy Co.: Sauz Ranch, sandy loam senior & D 23 Nov 1953 ( ). Cameron : Brownsville, o ound, Resa "3021 (F), 5804 (LL); Rio Hondo, Chandler 7067 (CH, MO, NY, UC MICH, M 11 Sept 1903 ( POM): Ram pen grass 4800 COAHUILA: Monclova, paar i ISA (US); Sabinas, Kenoyer 32 (F). 124 DUNCAN M. PORTER TAMAULIPAS: — de Mirandena, prairie on sandy loam shallowly overlying caliche, tchfield & Johnston 5552 (MEXU, MICH, TEX); near Victoria, ca. os m, Palnech 218 in part (F, GH, NY, UC, US). SIN- ALOA: rocky areas 12-15 km SE of Mazatlan, wet soil along road, 25 m, Worth ¢- Morrison 8812 (GH, MO, UC, US); Porvenir ee bot hebe 10 m, Gonzalez Ortega 5889 (DS, GH, PH, US). DURANGO: 3m of Durango, Hevly, Martin & Arms, 1 Aug 1960 (ARIZ). NAVARIT: te Maria Madre, edge of beach near penal colony, Ferris eg eee US): SAN LUIS POTOSI: locality unknown, Schaffner, 1876 (N COMMON NAME. Golondrina (Nayarit, Sinaloa, and Sonora, Mexico ). TAXONOMY. The name Kallstroemia brachystylis has been ap- plied to those specimens with fewer leaflets and less pronounced tubercles on the fruits than is usual for this species. However, Kearney and Peebles treating K. brachystylis as a variety of K. californica, pointed out that there was much intergradation in these characters. An examination of a number of collections made throughout the range of K. californica shows that variation in these characters is continuous, and there is no real justification for the recognition of two taxa. In the past, confusion has led to the recognition of two taxa. This confusion arose largely from the determination of a number of collections (usually immature or depauperate specimens) of Kallstroemia parviflora as K. brachystylis. Such determinations include at least two specimens (at NY and US) with the same locality and date as the type specimen of K. brachystylis. VARIATION. As indicated above, there may be considerable vari- ation in leaflet number (three to seven pairs) and fruit tubercles (blunt, oblong, and 1% mm long to less prominent), but this variation is of a continuous nature. Another character which occasionally shows marked variation is leaf shape. Although the overwhelming number of specimens have elliptical leaves, with the middle leaflets largest, some individuals have obovate leaves, with the terminal leaflets largest, and still others may have leaves of both shapes. Watson (1876); Brewer et al. (1876); and Gray (1887) have stated that Kallstroemia californica has five two-loculed and two-seeded carpels and a deeply five-lobed fruit. These statements undoubtedly are due to the only fruit on the holotype specimen (at least the only one now present) having the alternate carpels abortive and superficially appearing five-lobed. Close inspection shows it to be ten-lobed, typical for the genus. All the mature THE GENUS KALLSTROEMIA 125 mericarps of this species examined proved to be one-seeded, also typical for the genus. RELATIONSHIPS. Kallstroemia californica appears to be closely related to K. adscendens from the Galapagos Islands, Ecuador, and perhaps to K. standleyi from Oaxaca, Mexico. Kallstroemia adscendens differs in having hirsute and sericeous stems, two to three pairs of leaflets, fruiting peduncles longer than the subtend- ing leaves, persistent sepals, a strigose fruit with much less prom- inent tubercles, and a conical beak about % as long as the fruit body. Kallstroemia standleyi may be distinguished by its densely sericeous and sparingly hirsute stems, fruiting peduncles longer than the subtending leaves, persistent sepals, yellow-orange petals 10-12 mm long, linear-oblong anthers, style longer than the ovary, oblong stigma, and broadly ovoid strigose fruit 5-6 mm high and 7-10 wide, including the elongate blunt or slightly fungoid tubercles, which may be to 2 mm long. 9. Kallstroemia standleyi D. M. Porter, sp. nov. TYPE: Mexico, Oaxaca: sand dunes along beach, 0.5 mi E of Salina ruz, petals elle cea, 10-12 ms mm ine 16 July 1946, Thomas Morley 681 (cH, holotype; F. , UC, US, iso s). This species is named in honor of Paul Carpenter Standley (1884- 1963), prolific writer on the flora of the Aumarices and student of the Zygophyllaceae nua; caules prostrati, 1.5-2 dm longi, dense sericei, sparse hirsuti, ie aaes alba, antrorsa; stipulae 3-4 mm longae, 1-1.5 mm latae; folia elliptica, 2-3 cm longa, 1-1.5 cm lata; foliolorum pares , elliptica vel anguste ovata, sericea, 8-11 mm lon : , pares in medi a e maxima; pedunculi quam folia subtendentia longiores, ad apicem incrassati, ad anthesin 2.5-3 cm longi, in fructu 2 et curvati; sepala anguste ovata, 5-8 mm longa, lata, in fructu -mericarpia longiora, quam rostrum breviora, in fructu e basi patentia, margines deinde involuti, persistentia; petala luteo-aurantiaca, 10-12 mm longa, late obovata; amina et stylus aequilongus; antherae lineari-oblongae, 4 mm longae, antherae et pollen luteum; ovarium ovoi ide 1.5-2.5 diametro, pubescens; stylus 3-3.5 mm longus, cylindricus, ad basin strigosus; stigma oblongum, 1 mm longum, 10-porcatum, papillosum; fructus late ovoideus, 5-6 mm altus, 7-10 mm latus (tu ong bee geen strigosus; rostrum 4—5 mm longum, quam fructificatio 1/2 brevius, cylindricum, ad basin conicum trigosumque; mericarpia 5 mm alta, ca. ms mm lata, nga pluritubercu- re tubercula ad 2 mm longa, obtusa ad _— elongata, in maturitate ; stems prostrate, 1.5-2 dm long, oe sericeous and sparingly a with white apicall irected — anand — lon ong, 1-1.5 pens elliptical to narrowly ovate, sericeous, 8-11 mm n Jon ng, mm wide, middle pairs largest; uncles longer than subtending ——s« “thickened Y 9-2.5 em long in flower, 2.5-3 cm long and curved in fruit; sepals narrowly 126 DUNCAN M. PORTER ovate, 5-8 mm long, 2-3 mm wide, sericeous, spreading from base of mature fruit and longer than mericarps but shorter than beak, margins becoming involute, persistent; petals yellow-orange, 10-12 mm long, broadly obovate; ens a ow; n diameter, pubescent; style 3-3.5 mm long, cylindrical, base strigose; stigma oblong, 1 mm long, 10-ridged, papil- lose; fruit broadly ovoid, 5-6 mm high, 7-10 mm wide including tubercles, strigillose; beak 4-5 mm long, ca. 1/2 to as long as fruit body, cylindrical, base conical and strigose; mericarps 5 mm high, ca. 1 mm wide, abaxially with several elongate blunt to slightly fungoid tubercles to 2 mm long, coming more pronounced as fruit matures, sides pitted, adaxial edge straight. Fig. 9a, 9b. Map 11. FLOWERING DATES. Known to flower in July. DISTRIBUTION AND HABITAT. Known only from the type locality (Map 11). Both Kallstroemia maxima and K. pubescens are known from the same general area. DISTINGUISHING CHARACTERISTICS. Kallstroemia standleyi may be distinguished by its elliptical leaves, four to six pairs of leaflets, fruiting peduncles longer than the subtending leaves, sericeous sepals which spread from the base of the mature fruit, their margins becoming involute, yellow-orange petals 10-12 mm long, linear-oblong anthers 4 mm long, cylindrical style longer than the ovary, oblong ten-ridged stigma, broadly ovoid strigose fruit 5-6 mm high and 7-10 wide, including the prominent elongate blunt to slightly fungoid tubercles, which may become 2 mm long, and beak % to as long as the fruit body. RELATIONSHIPS. Kallstroemia standleyi appears to be most closely related to the more northerly K. californica. The latter differs in having hirsute and strigose stems, fruiting peduncles shorter than the subtending leaves, yellow flowers to 1 cm in diameter, usually deciduous sepals, conical style shorter than the ovary, ovoid strigillose fruit up to 4 mm high and 3-5 wide, including the prominent elongate blunt tubercles, which become 1% mm long, and the beak shorter than the fruit body. 10. Kallstroemia boliviana Standl., Field. Mus. Nat. Hist. Publ. Bot. 11:161. 1936 TYPE: Bolivia, Cochabamba: Cerro San Pedro, Cochabamba, elev. 2600 m, 25 December 1928, José Steinbach 8784 (Fr, holotype; BM, GH, MO, NY, US, isotypes ). Tribulus maximus var. roseus O. Ktze., Rev. Gen. Pl. 3(2):30. 1898. TYPE: Bolivia, Cochabamba: Parotani, elev. 2400 m, 20 March 1892, Otto Kuntze s. n. (Ny, holotype; ny, i : Perennial; stems prostrate to decumbent, to 5-8 dm long and several dm THE GENUS KALLSTROEMIA 127 high, hirsute and sericeous with white apically-directed trichomes; stipules 3-6 mm long, 2-3 mm wide; leaves obovate, 2.5-3 cm long, to ca. 2 cm wide; leaflets 2-3(—4) pairs, broadly ovate, sericeous, 12-23 mm long, 7-14 mm wide, terminal pair largest; peduncles longer than subtending leaves, thickened distally, 7-35 mm long in flower, 8-41 mm long and curved in fruit; flowers pentamerous, 2-3 cm in diameter; sepals ovate, 6-9 mm long, c m wide, ca. 1/2 as long as petals, hirsute and strigose, longer than style in flower, in fruit clasping and almost entirely covering ma i carps but shorter than beak, scarious m y or not become invol- e S > stigma oblong, 10-ridged, 1-2 mm long, a fruit ovoid, cyli stigma base; mericarps mm high, ca. 1 mm wide, abaxially rugose and g margins flattened, sides pitted, adaxial edge angled. Fig. 10a, 10b. Map 12. FLOWERING DATES. October through April, following summer rains. DISTRIBUTION AND HABITAT. Disturbed areas in the semiarid val- leys on the eastern face of the Cordillera Oriental of Bolivia, and known from a single similar locality in Peru (Map 12). Occurring from about 1100 to 2800 m. DISTINGUISHING CHARACTERISTICS. Kallstroemia boliviana may be distinguished by the combination of its perennial habit, obovate leaves, usually two or three pairs of sericeous leaflets, yellow to orange flowers (bases darker) 2-3 cm in diameter, hirsute and strigose sepals that clasp and almost entirely cover the mature mericarps, the scarious margins may or may not become involute, red anthers and pollen, conical ovary, oblong ten-ridged stigma, strigose fruit, with the beak longer than the fruit body, and the mericarps abaxially rugose with flattened margins. SPECIMENS EXAMINED. PERU. Se eae (eh Rio Mantaro Valley, S). NE of Pampas, 1300-1 m, Weberbauer 6516 BO WITHOUT LOCALITY: Mandon s. n. (F). LA am m, Buchtein 97 (GH), 2400 m, 671 (BM, F, MO, NY), 3198 (GH, NY, US); San Pedro, near Sorata, 2 2700 m, Ma (GH), 899 (BM, NY). COC AMBA: Cerro San Pedro, near Cochabamba, sandy p Cardenas 2260 (GH), hard-pac 128 DUNCAN M. PORTER beyond Rosario, dry bank, 8400 ft, Brooke 5228 (F, NY); Samaipata, sandy soil, 1120 m, Cardenas 3130 (US); Tako Tako, farm near Mizque, edge of ee land, 2035 m, Brooke 5889 (F, NY); Las Yungas, 6000 ft, Rusby 739 (MICH, NY). SANTA CRUZ: Puente Pilato (Morochata), sandy soil, 2600 m, Cardenas 4446 (US). TARIJA: Padcaya, 2100 m, Fiebrig 2511 (GH); outskirts of Tarija, semiarid plain, 1900 m, West 8290 (GH, MO, Cc ber a collection was made w Pampas,” sale that of K. Wetliianh was made “northeast of Peiapai RELATIONSHIPS, Kallstroemia boliviana is most closely related to the more southerly K. tribuloides and perhaps to the more north- erly K. pennellii. Kallstroemia tribuloides differs in its annual habit, sericeous stems, elliptical leaves, three to six pairs of leaflets, occasionally hexamerous orange flowers 12-24% mm in diameter, broadly ovate sepals, with the margins not becoming involute, linear-oblong anthers, and glabrous fruits. Kallstroemia pennellii has an annual habit, strigose stems, elliptical leaves, three to four pairs of leaflets, fruiting peduncles about 8 cm long, sericeous sepals 15 mm long, with the margins not becoming involute, and longer than the beak in fruit, yellow petals 3 cm long, the fruit strigillose, with a glabrous beak, and the mericarps abaxially cross- ridged and slightly keeled. 11. Kallstroemia tribuloides ( Mart.) Steud., Nomencl. Bot. ed. 2. The n “Kallstroemia tribuloides (Mart.) Wight & Arn., Prodr. 1:145. 1834.” poe a used for this taxon, but as sersmgove under ee: maxima and pointed out by Pore (1958) the combin made by Wight and arte St euda ] was the first to validly pabak the - eoea bination ott. ype din pow aI Mart., Nov. Gen. Sp. Brasil. 2:73. 1827. Type: presumably at Br or M, not seen). There can be no doubt as to the application of this pare far to von Martius’ excellent colored illustration of the me (his p Tribul asiliensis tie g., Syst. Veg. ed. 16. 4(2):343. 1827. nom. ee Based on Ehrenbergia ‘ribuloides, cited as a synon ems prostrate to decumbent, to 6 dm long, densely sericeous with spicaliy teed white trichomes, becoming glabrate; stipules 4-8 mm long, 1-2 mm wide; leaves elliptical, 3-7 cm long, 2-3 cm wide; leaflets THE GENUS KALLSTROEMIA 129 than beak, margins not becoming involute, persistent; petals orange, basally sometimes darker, obovate, 7— m lon ide, marcescent; stamens as long as style; anthers linear-oblong, rarely linear, 1 mm long, they pollen orange; ovary conical, 2-3 mm high, glabrous; style 3 mm long, cylindrical, base conical; stigma oblong, 10(-12)-ridged, ca. 1 mm long, papillose; fruit ovoi mm in diameter, glabrous; beak 3-10 mm long, glabrous, cylindrical, base conical; mericarp. FLOWERING DATES. November through May following summer rains. DISTRIBUTION AND HABITAT. Semiarid northeastern Brazil, south- ern Bolivia, and northwestern Argentina (Map 13). Apparently native to Argentina and Bolivia and introduced into Brazil. Open sandy places, riverbanks, railroad embankments, and roadsides from 300 to 1800 m. Sympatric over much of its range with Kallstroemia tucumanensis. DISTINGUISHING cHARACTERISTIcs. Kallstroemia tribuloides is easily recognized by its combination of densely sericeous stems, elliptical leaves, three to six pairs of leaflets, rarely hexamerous orange flowers 1%-2% cm in diameter, broadly ovate hirsute and strigose sepals which clasp and almost entirely cover the mature mericarps, the margins not becoming involute, linear-oblong anthers, conical ovary, oblong ten-ridged stigma, glabrous fruit, with the beak usually longer than the fruit body, and the meri- carps abaxially rugose with flattened and slightly keeled margins. Kallstroemia tribuloides is commonly found growing with (but is not likely to be confused with) the obovate-leaved, small, yellow- flowered, and strigose-fruited K. tucumanensis. SPECIMENS EXAMINED. BRAZIL. PIAUI: Boa Esperanga, Gardner 2084 (BM, GH, NY). BAHIA: Joazeiro, Curran 252 (GH, US). ALAGOAS: Ilha Sao Pedro, Rio do Sao Francisco, open sandy places, Gardner 1264 (BM, eins TARIJA: Villamontes, Pflanz 2001 (US). ARGENTINA. SALTA: Burela, Luna 979 (CAS); Metan, O’Donell 2488 50 107 Tapia, 820 ex ) MO, UC); Tapia to Cadellal, 500 m, Schreiter 1028 (DS, F, GH, NY, UC); Tapia to Vipos, 750 m, O’Donell & Lourteig, 4 Feb 1939 (DS, F, GH, 130 DUNCAN M. PORTER NY, UC); Vipos, fields, Lillo 7896 (F, GH), 786 m, art ( Schreiter 1910 (F), 24 Jan 1926 in DS, F, GH, NY, UC). CATAMARCA: Campo del In addition, collections aha have not been seen have been reported from the states of Rio Grande do Norte, Brazil (von Luetzelburg, 1923), and Jujuy (Descole, et al., 1940) and Mendoza (Ruiz Leal, 1947), Argentina. COMMON NAME. Rosa do Campo (Brazil). VARIATION. Ruiz Leal (1947) reports that specimens of Kall- stroemia tribuloides from Mendoza, Argentina, had flowers half the size (ca. 1 cm in diameter) and were more reduced in height than those from farther north. These differences probably were due to environmental factors. The collections which he cited have not been seen. RELATIONSHIPS. Kallstroemia tribuloides is most closely related to the more northerly K. boliviana and perhaps to K. pennellii. Kallstroemia boliviana differs in its perennial habit, hirsute and sericeous stems, obovate leaflets, usually two to three pairs of sericeous leaflets, yellow to orange flowers 2-3 cm in diameter, globose anthers, and strigose fruits. Kallstroemia pennellii has strigose stems, three to four pairs of leaflets, fruiting peduncles about 8 cm long, sericeous sepals 15 mm long, longer than the beak in fruit, yellow petals 3 cm long, strigillose fruits, and the mericarps abaxially cross-ridged and slightly keeled. 12. Kallstroemia pennellii D. M. Porter, sp. nov. TYPE: Peru, Cajamarca: along Rio Marafion, above Balsas, Amazonas, river bank, west shore, elev. 700-900 m; herb, petals yellow (lemon-chrome), 15 April 1948, Francis W. Pennell 15185 (PH, holotype). This species is named for-Francis Whittier Pennell (1886-1952), longtime Curator of Plants at the specimen. Annua; caules ad 3 dm longi vel longiores, strigosi, trichomata antrorsa, alba, deinde , ca. 1mm glabrati; stipulae 4-5 ca. 2 cm i; ite €rosa, marcescentia; stamina et stylus aequilongus; stylus ca. 10 mm longus; stigma oblongum, 2 mm longum; fructus Grckdeon, THE GENUS KALLSTROEMIA 131 strigillosus; rostrum 8 mm longum, cylindricum, ad basin conicum, glabrum; mericarpia 5 mm alta, abaxialiter rugosa et subcarinata. Annual; stems to 3 dm long or longer, strigose with white apically-directed ichomes, becoming glabrate; stipules 4-5 mm long, ca. 1 mm wide; leaves elliptical, 2-4 cm long, to ca. 2 cm wide; leaflets 3-4 pairs, broadly elliptical to ovate, sericeous, 9-14 mm long, 3-6 mm wide, middle pairs largest; peduncles longer than subtending leaves, thickened distally, To and ca. 8 cm long in fruit; sepals ovate, 15 mm long, 3-4 mm wide, 1/2 as long as petals, sericeous, scarious margins not becoming involute, lon _ than style arly notched, i 1 t cylindric , glabro rp. ined se slightly rasa Fig. 12a, 12b. ap 5. FLOWERING DATES. Known to flower in April. DISTRIBUTION AND HABITAT. Know only from the type locality (Map 5). DISTINGUISHING CHARACTERISTICS. Kallstroemia pennellii is char- acterized by its strigose stems, elliptical leaves, three to four pairs of sericeous leaflets, fruiting peduncles about 8 cm long, sericeous sepals 15 mm long, longer than the beak in fruit, the scarious margins not becoming involute, yellow petals 3 cm long, strigillose fruit, the beak glabrous and longer than the fruit body, and the cross-ridged and slightly keeled mericarps. RELATIONSHIPS. Kallstroemia pennellii perhaps is most closely related to the more southerly K. boliviana and K. tribuloides. Kall- stroemia boliviana differs by its hirsute and sericeous stems, obovate leaves, usually two to three pairs of leaflets, fruiting peduncles to about 4 cm long, hirsute and strigose sepals 6-9 mm long and shorter than the beak in fruit, yellow petals 12-19 mm long, strigose fruit, and abaxially rugose mericarps with flattened margins. Kallstroemia tribuloides has densely sericeous stems, three to six pairs of appressed-hirsute and sericeous leaflets, occa- sionally hexamerous orange flowers 1-2% cm in diameter, broadly ovate hirsute and strigose sepals shorter than the beak in fruit, glabrous fruit, and abaxially rugose mericarps with flattened and slightly keeled margins. 13. Kallstroemia grandiflora Torr. ex Gray, Pl. Wright. 1:28. 1852 type: Arizona, Graham Co.: Bese of the Gila,” 28 October 1846, 132 DUNCAN M. PORTER 1848), on this date he was in what is now Graham Co ounty, Arizona, and collected along need near the Gila River. This specimen speci 2 is the syntype cited by t was panei selected as the lectotype by Ryd- erg (in Vail & Rpts 1910, p. 114), who wrote “Type locality: ae of the Gila River, Arizona otwithstandin Gray’s citation of the author- ship of this species (cf., Gray, 1853) as “Kallstroemia grandiflora Pl. Wright.”, the correct citation undoubtedly is “Torr. ex Gray” rather than Torr. in Gray,” although Torrey himself used the latter ie Torr rey, 1859). The original publication reads “Kallstroemia grandiflora (Torr. in herb. Hook.),” which leads one to conclude that this was a name taken by Gray from an annotation by Torrey on a specimen in W. J. Hooker’s a rather than a name and description provided by Torrey. F evidence is provided by Gray’s original comment that, “Orders or genera | elaborated by Dr. Engelmann, Dr. Torrey, Mr. B entham, or others fos =| thes case that I can discover is a species pub- Gray. Gray probably came upon this name on his visit to Scotland in 1838- ; ao i i pi F Kallstroem ndiflora detonsa Gray, op. TYPE: Texas, “Near El Paso? Sept 1849, Chaves Wright 75 (on Toi oe NY, holotype photograph; cu, Tribulus aati. (Torr. ex Gray) Brew. & Wats. in Brew., Wats. & Gray, Bot. Calif. 1:91. 1876. Brewer and Watson erroneously attributed this to be a ae of Tribul Tribulus fisheri Kell., Proc. Calif, Acad. 7:162, 1877. ipod Mexico, Son- ora: Agiabampo, 15 Sept. 1876, Wm. J. Fisher s. n. (uc, h Kallstroemia grandiflora var. arizonica Cockll., Bull. Torr. “Bot. Club 27:87. 1900. rye: Arizona, Maricopa Co.: Phoenix, 9 Oct. 1899, T. D. A. Cockerell sn. { Helotype presumably at COL, not seen; NY, sotypes ). Annual; stems decumbent to ascending, to over ie m iki and ca. 1 m nie ensely sericeous with white and hispid with white or yellow — % pega trichomes, rarely becoming glabrate; rae 4-10 mm long, 1 wide; leaves ellipti tical, 1.5-7 cm long, 2-3 cm wide; leaflets roe per a = = 8 - mm long, 7-22 mm wide, marcescent; stamens as lon le; anthers ovoid or oblong, rarel linear, 2-3 mm eg they hey pollen red, orange, or rarely yellow, same color as petal base; ovary o mm in diameter, pa style 6-8 mm long, a oeinical base ‘slightly conical, strigose at or to stigma base; stigma clavate, 2-3 mm long, 10-ridged, papillose; fruit ovoid, 4-5 mm in diameter, strigose; beak 6-18 mm long, ca. 3 times THE GENUS KALLSTROEMIA 133 length of fruit body, cylindrical, base conical, strigose at base or to stigma base; mericarps ca. 3.5 mm high and 1 mm wide, abaxially turbercled, sides slightly pitted, adaxial edge angled. Fig. 13a, 13b. Map 14. FLOWERING DATES. In the north flowering mainly from June through October after the summer rains, and in the southwest (Jalisco to Guerrero) from August to March. DISTRIBUTION AND HABITAT, Common in flat sandy areas through- out the Sonoran (except for Baja California) and Chihuahuan deserts from sea level to about 2000 meters; continuing southward through the semiarid lowland formations from Sinaloa to north- ern Guerrero and sparingly northward in Arizona (Map 14). In the north sympatric over much of its range with Kallstroemia californica, K. hirsutissima, K. parviflora, and K. perennans, and in the southwest overlapping with K. hintonii, K. maxima, K. pubescens, and K. rosei. DISTINGUISHING CHARACTERISTICS. Kallstroemia grandiflora is easily recognized by its combination of decumbent to ascending stems, elliptical leaves, four to ten pairs of leaflets, fruiting peduncles longer than the subtending leaves and extending the flowers well above the herbage, white to bright orange flowers (the petal bases from green to red) 2-6 cm in diameter, lanceo- late hispid and strigose sepals that much surpass the mature mericarps but are shorter than the beak, shriveling and turning brown and the margins becoming strongly involute making them appear linear, cylindrical style about three times as long as the ovary, clavate ten-ridged stigma, and strigose fruit with the beak about three times as long as the fruit body. Kallstroemia parviflora and K. perennans are the only species from the same area with which K. grandiflora is likely to be confused. Kallstroemia parvi- flora differs in its having three to six pairs of leaflets, fruiting peduncles 1-4 cm long, orange flowers 1-2% cm in diameter, the anthers less than 1 mm in diameter, always yellow anthers and pollen, and oblong ten-ridged stigma; only depauperate individ- uals of K. grandiflora will be confused with this species. Kall- stroemia perennans differs in having a perennial habit, densely hispid and strigose stems 1-2 cm long, four to five pairs of densely pubescent leaflets, fruiting peduncles shorter than the subtending leaves, fugaceous but not marcescent orange petals, the stamens only two-thirds as long as the style, oblong ten-ridged coarsely canescent stigma extending along the upper one-third of the 134 DUNCAN M. PORTER style, broadly ovoid hispid and strigose fruits 5-6 mm high and 8-10 wide, the beak hirsute at the base, and the mericarps abaxi- ally cross-ridged and more or less keeled and 24 mm wide. REPRESENTATIVE SPECIMENS EXAMINED. UNITED STATES. CALI- _ FORNIA. Riverside Co.: Chuckawalla Valley near Desert Center, open ground near roadside, sandy soil, 900 ft, Clary — (POM). ARIZONA. Coconino Co.: Bill Williams ig Anderson, July 1864 (MO). Navajo Co.: McNary-Globe road near White River, Gunning 3183 (ARIZ). Yavapai Co.: Beaver Creek, Rusby, Aug 1883 (F, 7, Fe ; mi above co) roadside, J. D. Porter, 30 Aug 1962 (GH); Sentinal, M. E. Jones 24962 (CAS, GH, MO, NY, POM, UC). Gila Co.: near Globe, Peebles, Harrison ¢ Kearney 4391 ( ARIZ, US); mesa near Rock & Rye Creeks, 990-1050 m, Collom 187 (GH, MICH, MO, NY, US); San Carlos, 2500 ft, Rothrock 777 (F, GH, RSA, US). Pinal Co.: desert mesa near Ap ache Junction, Gillespie 8442 (DS, GH, UC, US); Oracle, 4500 ft, Doris, 9-13 Sept 1905 ( ARIZ, ge Sacaton, Gilman s. n. (MO), 271 (DS, MO), 283 (CAS). Graham Davidson 14 (UC), 758 (DS). Pima aboquivari Canyon, Gilman 22 (DS, F, MO, NY); Continental, Shreve 6600 ( ARIZ, DS, MICH); Tucson, 2400 ft, Thornber 263 (ARIZ, : : : , UC). Santa ruz Nogales, E. Jones 22312 (F, MO, POM); near Ruby, ca andy soil, 4300 ft, Benson 738 4 (PO M). Luna Co.: near as. sd alert OT ITA (SMU); Florida Mts., Mulford 1073 (MO, NY). Dona Ana Rio Grande near Ft. Selden, Rusby 56 (F, MICH, MO, NY, PH); Rio ‘Gaal pa below Dona Ana, Parry, et al. 139 (NY, PH, US). TEX- El Paso Co.: El Paso, alluvial hills, sige m, Fosberg $3898 (GH, LL, et SMU); Franklin Mts., limestone soil, 4300 ft, Lath gia 8226 (LL, MICH, SMU, TEX). Hud ispeth Co.: neraott en Nulo and Harris Siding, Ferris & Duncan 2447 (DS); 5 mi W of Van Hom, gravelly soil along high- way, Warnock 13619 (LL, TEX). Loving Co.: ca. 3 mi W of Mentone, Brewster Co.: Big Bend Natl. Park, 6 mi N of Rio ago dry swat. 3000 ft, Rollins ¢ Chambers 2768 (DS, GH, UC, US); B Deel Nong Meaeh 53 (GH, SMU, TEX); arroyos near Hot Springs, Warnock, 17 tal 1937 (ARIZ, GH, >. MEXICO. SONORA: Guaymas, hills and valleys, Palmer 177 (BM, DS, THE GENUS KALLSTROEMIA 135 GH, NY, PH, UC, US), stony slopes, 225 (BM, GH, MICH, NY, US); ano 27 mi W of Hermosillo toward Kino Bay, Wiggins & Rollins 129 ( ARIZ, , GH, Tg MO, ad? San wince Sage mesas and milpas, sont f 1667 X 1 H. oO, poviny TEX, UC); Hacien a San Miguel, near elective Palmer 108 (BM, CAS, GH, MICH, NY, PH, rea COAHUILA: 2 km NE of Las Delicias, caliche slopes, Stewart 2958 (GH); dry valley between La Vibora and Matrimonio Viejo, gypsum beds, Johnston 9338 (GH). SINALOA: tacts. i 1440 (F, GH, NY, US); low hills 8 mi N of Mazatlan, Waterfall 12751 (ARIZ, GH, MICH, ge: ae mae, Rosario, Lamb 471 (DS, GH, MICH, MO, MSC, NY, US). D NGO: base of hills 2 mi W na ype yes me toward Palmito Dam, silty oe Tolnston 7749 (GH); 27 mi of Cuencame toward Torreén, desert scrub, among ft, hd & Forman 1520 (MICH, RSA). NAYARIT: Keigooea Lamb 530 (GH, MO, MSC, NY, US), 534 (DS, GH, MSC, NY, US); Cajion de Jesus Maria, bottom lands along Rio Jesus Maria, 1000 ft, Goldsmith 141 (F, GH, MO, UC, US). JALISCO: between La Venta and Ixtlan, 1100 m, Reko 4491 (US). COLIMA: Colima, Palmer 83 (ARIZ, MICH, UC, US), 1110 GUERRERO: Pungarabato, bank of Rio Cutzamala, "Hinton 6480 {F. GH, are NY, US). A specimen at PH labeled “Moore’s Flat, Sierra Nevada, Nevada Co., Cal. July 1867.” could not have been collected in this locality, far from the range beach.”, was Siebede switched with a specimen 0 occurs in that locality. This collection of K . grandiflora Mac ci is ae Arizona, where Schott also collected. COMMON NAMES. Like many other plants with conspicuous flowers, Kallstroemia grandiflora is graced with a number of com- mon names. However, surprisingly, it is not known by nearly as many names as is the much less conspicuously flowered K. max- ima. This undoubtedly is due to the latter’s wide use in the native materia medica, while the former is utilized, if at all, only as an ornamental. Common names that have been reported for K grandiflora are Abrojo de Flor Amarillo (Chihuahua, Durango); Arizona Poppy (Arizona); Baiburin (Sinaloa, Sonora); Desert Poppy (T ey Mal de Ojos (Sonora); Manrubio (Colima); Mexican Poppy, Ojo Mal, Poppy (Arizona); San Miguelito (Son- ora); and Summer Poppy (Arizona). Prevalence of the word “poppy” as part of the common name in much of the southwest- ern United States reflects the superficial resemblance of the flowers in size and color to the California Poppy, Eschscholzia 136 DUNCAN M. PORTER californica Cham. (Papaveraceae), commonly grown in the same area as an Ornamental. VARIATION. Variation in the color of trichomes on the vegetative parts of the plants is sometimes quite striking. If the larger, hispid trichomes are yellow, as is normally the case, individuals have a decided yellowish cast. If these trichomes are white, the plants appear gray. Specimens from the Sonoran Desert and its environs tend to be yellow, and those from the Chihuahuan Desert tend to be gray, but this criterion is too variable to be utilized in the recognition of subspecific entities. Flower color in Kallstroemia grandiflora is rather variable, but that of individual populations appears to be remarkably stable. It ranges from yellow to distally orange with a dark orange basal spot, or dark orange with a red basal spot. Occasional populations are found in which the petals are white with a red basal spot. There appears to be genetic linkage between the color of the petal base and filament, anther, and pollen color. All are the same in an individual. This color variation is not such that subspecific taxa can be recognized, in that it appears to have no ecological or geographical correlation. RELATIONSHIPS. Kallstroemia grandiflora appears to be the cen- ter of a group of interrelated species also involving K. parviflora, K. peninsularis, and K. perennans. The characters distinguishing K. parviflora and K. perennans from K. grandiflora are summa- rized above. Kallstroemia peninsularis differs in having hirsute and hirtellous stems with retrorse pubescence, two to five pairs of leaflets, yellow to orange flowers 1-3% cm in diameter, hispid and hirtellous sepals, yellow anthers and pollen, and a clavate stigma that extends along the upper one-third to almost the entire length of the style. 14. Kallstroemia peninsularis D. M. Porter, sp. nov. TYPE: Mexico, Baja California Sur: granitic hills 10 mi SE of La Paz on road to Los Planes, elev. 725 ft; petals golden yellow, 1 December 1959, Tra L. tt 15686 (cu, holotype; ps, GH, TEX, isotypes Annua; caules prostrati vel decumbentes, decimetra aliquot longi, albi- vel lutei-hirsuti et hirtelli, trichomata retrorsa; stipulae 2-4 mm longae, 1-2 mm latae; folia elliptica, 1.5-6.5 cm longa, 2-4 cm lata; foliolorum pares 2-5, ror la elliptica vel ‘oblonga, appresse hirsuta, — venaeque sericeae, longa, mm lata, pares in medio laminae maxima; unculi quam fla folia puting ag longiores vel fase ad os cem incrassati, an- esin 10—5: ongi, in fructu 19-64 mm longi, ad basin acute flexi et sursum - ‘ean pentameri, 1-3.5 cm in diametro; sepala subulata, 5-8 THE GENUS KALLSTROEMIA 137 mm longa, 1-2 mm lata, quam petala 1/2-1/3 breviora, Jutei-hispida et albi- hirtella, ad anthesin ech stylus longiora, in fructu mericarpia matura multo excedentia sed quam rostrum breviora, margines deinde perinvoluti et quasi- apice centia; stamina et stylus aequilongus; antherae ovoideae, 1-2 mm in diametro, antherae et pollen luteum; ovarium ovoideum, 1-3 mm in diametro, pube- m | scens; stylus ngus, anguste cylindricus, ad basin leviter conicus, ad basin stigmatis stekeceriay” > gm vatu ongitudine subae- quans vel 2/3 brevius, 10-porcatum papillosum; fructus iailies in diametro, strigillosus; chorea _ dricum, ad basin conicum, ad stigmatam strigosum; mericarpi ca. 1 mm Jata, abaxialiter phecdate-tiberoalats, fence foveolata, adaxialiter Pee. gay Annual; stems prostrate to dec umbent, to sev eral dm g, hirsute with white or yellow oo hirtellous with white retrorse trichomes; piles 2-4 mm long, 1-2 mm wide; leaves elliptical, 1.5-6.5 cm lon ng, 2-4 cm wide; leaflets 2-5 pairs, elliptical to Bh gence ir pressed-hirsute, veins and margins sericeous, 8-34 mm lon wit, middle pairs largest; need longer or shorter than apy richie thickened distally, 1 mm ong in flower, 19-64 mm long in fruit and ‘bent sharply at base a straight strongly involute making them appear almost linear, Aimar petals yellow d to orange, broadly obovate, apex broadly roun rregularly notched, 11-20 mm long, m e, marcescent; ai style; ares ovoid, 1-2 in diameter, they and pollen yellow; ovary ovoid. m di ubescent; style mm long, narr lindrical, owly c bee slightly Sata strigose to stigma base; stigma clavate, extending along upper 1/3 to ca. entire length of style, lo-tidged, papillose; fruit ovoid, 3. mm in diameter, sasmginsah e mm long, ~~ cal, base conical, strigose to stigma base ees ag h, ca. 1 mm wide, abaxially 1g with — tubercles, sida pitted, adaxial edge ‘slightly angled. Fig. 14a, 14b. Map FLOWERING DATES. August through March, following both sum- mer and winter rains. DISTRIBUTION AND HABITAT. Endemic to the southern part of the territory of Baja California, Mexico (Map 15). Found mainly in low sandy areas and sand dunes near beaches from sea level to perhaps 1000 meters or higher. Kallstroemia californica also extends into this area. DISTINGUISHING CHARACTERISTICS. Kallstroemia peninsularis is easily recognized by its combination of hirsute and hirtellous stems with retrorse trichomes, elliptical leaves, two to five pairs of leaflets, yellow to orange flowers 1-32 cm in diameter, hispid and hirtellous sepals which are longer than the mature mericarps but shorter than the beak, shriveling and the margins becoming 138 DUNCAN M. PORTER strongly involute and making them appear almost linear, yellow anthers and pollen, narrowly cylindrical style about three times as long as the ovary, a clavate stigma extending along the upper one-third to almost the entire length of the style, and strigillose fruit with the beak about three times as long as the fruit body. SPECIMENS EXAMINED. MEXICO. BAJA CALIFORNIA: Arroyo Salado, Purpus 409 (UC); near Arroyo Salado, margin of ocean sand dunes, Ham- merly 189 (CAS, DS); Cabo San Lucas, Xantus 14 (GH, NY, US); 3 km N of Cabo San Lucas, flat area, Moran 7040 (DS); 14.4 km SW of Comondt, steep slope in canyon, Carter, Alexander ¢> Kellogg 2122 (DS, US); 0.5 mi of SW base of Los Frailes, sandy dunes, Porter 318 (CAS, DS): arroyo Oo Paz, rocky sand at roadside, Porter 438 (DS); ca. 15 mi W of La Paz. coarse granitic sand on bluff, Hammerly 222 (CAS, DS, US); gulch in granitic hills 15.5 mi SE of La Paz toward Las Cruces, 570 ft, Wiggins 15669A (DS); near 1 gsm of roads to Punta Arenas and Bahia de los Muertos. roc mi N of San Lucas, sandy decomposed granite in road, Porter 341 (DS); yi 12.8 km N of Santiago, granitic sand, Carter, Alexander ¢> Kellogg 2181 (DS, US). COMMON NAME. Patagallina. TAXONOMY. In a previous publication (Porter, 1963), this taxon was confused with Kallstroemia grandiflora and K. pubescens. However, a more adequate knowledge of the genus has revealed that it is a new species. RELATIONSHIPS. Kallstroemia peninsularis is most closely related to K. grandiflora. The latter differs in having densely sericeous and hirsute decumbent to ascending stems, four to ten pairs of leaflets, fruiting peduncles 3-10% cm long that extend the flowers well above the herbage, the flowers from 2-6 cm in diameter, hispid and strigose sepals, the petals basally darker in color than the distal portion, the anthers and pollen rarely yellow, a clavate ten-ridged stigma less than one-third as long as the style, and strigose fruits. 15. Kallstroemia perennans Turner, Field & Lab. 18:155, 1950 TYPE: Texas, Val Verde Co.: Langtry, May 1913, C. R. Orcutt 6126 (mo, |. ho holotype; cu, Mo, holotype photographs). Based on Kallstroemia hirsuta L. Williams, Ann. Mo. Bot. Gard. 22:49. 1935. Not K. hirsuta (Benth.) Engl. THE GENUS KALLSTROEMIA 139 in Engl. & Prantl, Nat. Pflanzenfam. 3(4):88. 1890 [=Tribulus hirsutus Benth., Fl. Austral. 1:289. 1863]. Perennial; stems prostrate to ascending, 1-2 dm long, densely hispid with bulbous-based white or yellow and strigose with white apically-directed trichomes; stipules 3-5 mm long, 1-1.5 mm wide; leaves elliptical, 2-5.5 cm long, 2-3 cm wide, densely pubescent; leaflets 4-5 pairs, one to ovate, densely appressed-hirsute, veins and margins sericeous, 13-18 mm long, 6-10 m wide, middle pairs largest; ia il, 2 shorter than subtending leaves, broadly ovoid, 5-6 mm high, 8-10 mm wide, hispid and strigose, hispid trichomes to 5 mm long; beak 6-10 mm long, cylindrical, base hirsute and slightly conical; mericarps 4 mm high, 2.5 mm wide, abaxially cross-ridged and more or less keeled, sides pitted, adaxial edge straight. Fig. 15a, 15b. ap 15. FLOWERING DATES. May through August, following the spring and summer rains. DISTRIBUTION AND HABITAT. The Chihuahuan Desert; known only from southern Presidio, Brewster, and Val Verde counties, Texas (Map 15), where apparently confined to limestone soils. Sympatric with Kallstroemia californica, K. grandiflora, K. hirsu- tissima, and K. parviflora. DISTINGUISHING CHARACTERISTICS. Kallstroemia perennans may be easily recognized by its having a combination of perennial habit, short prostrate to ascending stems, elliptical leaves, four to five densely pubescent leaflets, fruiting peduncles shorter than the subtending leaves, densely hispid and strigose sepals that spread from the base of the mature fruit and curve upward surpassing the mature mericarps but shorter than the beak, margins becoming sharply involute, orange petals that are fuga- ceous but not marcescent, stamens two-thirds as long as the style, a cylindrical style about twice as long as the ovary, oblong ten- ridged coarsely canescent stigma that extends about one-third the length of the style, broadly ovoid hispid and strigose fruit from 5-6 mm high and 8-10 wide, cylindrical beak about twice as long as the fruit body, and abaxially cross-ridged and more or less keeled mericarps 2% mm wide. The only species from the same 140 DUNCAN M. PORTER area with which Kallstroemia perennans might be confused is K. grandiflora. The latter differs from K. perennans in its annual habit, decumbent to ascending stems reaching to over 1 m in length, four to ten pairs of leaflets, fruiting peduncles longer than the subtending leaves, sepals shriveling and turning brown, the margins becoming strongly involute and making them appear linear, fugaceous and marcescent yellow to bright orange petals with usually a darker base, the stamens as long as the style, clavate ten-ridged papillose stigma, ovoid strigose fruit, and abaxially tubercled mericarps about 1 mm wide CIMENS EXAMINED. UNITED STATES. TEXAS. Locality unknow Rio | Calera V. Havard, 1883 (F). Presidio Co.: limestone hills hobeecn ock LL). Langtry, McVaugh 8226A (GH, MICH RELATIONSHIPS. Williams (loc. cit.) was the first to indicate that Kallstroemia perennans is most closely allied to K. grandiflora. The differences between these two species are reviewed above. 16. Kallstroemia parviflora Norton, Ann. Rept. Mo. Bot. Gard. 9:153. 1898 TYPE: Texas, Bexar Co.: San Antonio, 1897, E. H. Wilkinson 184 (m ee haia g Notwithstanding Rydberg’s (in Vail & Rydbere, 1910) Gactivect citation of Pollard 1295 as the type collection of this species by listing Agricultural College, Mississippi” for the type locality, Wilkinson's speci- men is the type. Both collections were cited by Norton in his description of the species, and the Wilkinson specimen at Mo bears the word “Type,” presumably in Norton’s handwriting. It is confirmed as the lectotype. Kallstroemia intermedia Rydb. in Vail & Rydb., N. Amer. Fl. 25:113. 1910. TyPE: Texas, Bexar Co.: 1904. Gust. Jermy s. n. (Ny, holotype; uc, holotype fragment). Kallstroemia laetevirens Thornb. in Woot. & Standl., Contr. U. $. Nat. THE GENUS KALLSTROEMIA 141 ser nag en 1-2.5 cm in diameter; sepals lanceolate, 4-7 mm long, 1-2 m wide, hispid with white or rarely yellow and stri ee with white trichomes, in flower longer than style, in fruit shriveling and turning brown, gees erica i dlidtbies, they foe flea n yellow; ovary ovoid, pore: scent, ca. 1 in diameter; style as long or longer than ovary, cylin 1dr ical, strigose to glabrous pe oblong, 10-ridged, ca. 1 a long, papillose; fruit ov oid, 3-4 mm : wide, strigose; beak 3-9 mm long, as long as to 3 times fruit body, pete to glabrous us, trichomes Es geet Ms grag: g ome base scarcely conical; mer igh, axially rugose to tubercled, sides lightly to protean pitted, ‘ducal ates fuatoery Fig. 16a, 16b. Maps 5, 16. FLOWERING DATES. Seed germination, plant growth, and flower- ing take place mainly after summer rains. These phenomena usu- ally occur from July through September in North America, and from November to April in Peru. DISTRIBUTION AND HABITAT. Disturbed areas mainly in various grassland associations from Colorado and Kansas south to Guana- juato, Querétaro, and Hidalgo, Mexico, and west to Arizona, occurring sparingly in the Chihuahuan Desert, extending as a weed in all directions; introduced into western and central Peru (Maps 5 and 16). Found from about 100 to 2600 m in North Ameri- ca and 1300 to 2850 m in Peru. Sympatric with Kallstroemia cali- fornica, K. grandiflora, K. hirsutissima, and K. perennans in the north, K. rosei in the south, and barely overlapping with K. maxi- ma in the southeast. DISTINGUISHING CHARACTERISTICS. Kallstroemia parviflora is dis- tinguished by its combination of elliptical leaves, three to six pairs of leaflets, fruiting peduncles 1-4 cm long, orange flowers 1-2% cm in diameter, hispid and strigose sepals longer than the mature mericarps but shorter than the beak, shriveling and turning brown and the margins becoming strongly involute, yel- low anthers and pollen, cylindrical style as long or longer than the ovary, oblong ten-ridged stigma, cylindrical beak as long to three times as long as the strigose fruit body, and abaxially rugose to tubercled mericarps. Depauperate specimens of K. parviflora may be confused with K. californica, and more robust specimens with K. grandiflora. Kallstroemia californica differs in having hirsute and strigose stems, three to seven pairs of leaflets, fruiting peduncles shorter than the subtending leaves, yellow flowers 1 cm 142 DUNCAN M. PORTER or less in diameter, usually deciduous sepals, a stout conical style shorter than the ovary, a clavate ten-ridged stigma, strigillose fruit with the beak shorter than the fruit body, and mericarps with four or five blunt oblong tubercles that may be 1% mm long. Kall- stroemia grandiflora has four to ten pairs of leaflets, fruiting peduncles 3-10% cm long, white to bright orange flowers ( petal bases darker than the distal portion) 2-6 cm in diameter, anthers 2-3 mm long, usually orange or red anthers and pollen, style about three times as long as the ovary, and clavate ten-ridged stigma. REPRESENTATIVE SPECIMENS EXAMINED. UNITED STATES. CALIFOR- NIA. San Bernardino Co.: Coliseum Mine, Clark Mts., dry sandy exposed D Co.: Oil Creek, Brandegee 705 (MO, NY, PH, UC). Pueblo Co.: Pueblo, along railroad track near depot, Baker, Earle & Tracy 4 (BM, F, GH, MICH, MO, NY, POM, UC, US). Otero Co.: La Junta, 6000-7000 ft, Beckwith 89 (NY). Bent Co.: Caddoa, Wooton, 13 Sept 1897 (US). Las Animas Co.: near Troy, Rogers 5396 (MICH, TEX, US). Baca Co.: breaks of East Car- rizo Creek 5 mi SW of Kirkwell, 4700 ft, Weber 5102 (RSA, UC). KANSAS F. ; a re) Eggert, 24 Aug 1902 (MO). Sedgewick Co.: Wichita, along A.T.&S.F. railroad, Bartley 1210 (NY, US). Meade Co.: Advance Flag Station, dry grassland, 2550 ft, Horr 3436 (GH). MISSOURI. Jackson Co.: Kansas City, waste ground, Bush 8168 (GH, MO, NY, US), 8168A (CAS). St. Louis Co.: Allenton, erman, 1897 (MO). St. Louis City: St. Louis, railroad banks, TEX, » US), A : 1 : Peebles 12594 (ARIZ, US). Coconino Co.: Havasupai Canyon, flat areas, Clover 7007 (SMU). Navajo Co.: Holbrook, Zuck, 10 Aug 1896 (F, MO, NY, US). Apache Co.: Navajo Indian Reservation near N end of Carrizo Mts., hills, Standley 7475 (US). Yavapai Co.: Prescott, Peebles, Harrison & earney 8862 (ARIZ, F, POM). Gila Co.: mesa near Rock Creek. 1050 m, Collom 322 (MICH, MO, US). Maricopa Co.: Agua Caliente, Thornber in .: San Tan Mts., Peebles, Harrison ¢+ Kearn 145 ( ARIZ). Greenlee Co.: Blue River, Davidson 757 (DS, UC). Pima Co.: Stone Cabin Canyon, Santa Rita Mts., Griffiths & Thornber 284 ( ARIZ, NY, ruz Co.: 1 mi E of Canelo, desert assland, Benson 1149 {DS, POM). Cochise Co.: Paradise, under ditch, Blumer 2272 ( ARIZ, F, THE GENUS KALLSTROEMIA 143 . NEW MEXICO. San Juan Co.: desert draw S of Shiprock, sand, Water- al 11 730 (RSA, TEX, UC, US). Rio Arriba Co.: Chama River, Wooton 7 (US). Taos Co.: Ojo Caliente, 6000 ft, B. H. Smith, 25 Aug 1893 me). Colfax Co.: Raton, Cockerell, 29 Aug 1900 (NY). Santa Fe Co.: Santa Fe, 7200 ft, Heller & Heller 3746 (BM, DS, GH, MSC, NY, US). San Miguel Co.: Las Vegas, 1900 m, Bro. Arsene 16203 (BM, F). Quay Co. SMU). Catron S Bat Cave, 14 mi SW of Horse sien A soil on canyon floor, C. E. Smith 213 (ARIZ, PH). Socorro C Vasey 69 (BM, F Faby 1881 (F, US). Lincoln Co.: Gray, ¢ ft Skehan - se GH, ‘MO; NY, POM, U win Chaves Co.: 20 mi S of Roswell, U Co.: White Pen. —— Pe Aug 1899 (US). Eddy Ons near US High- of Texa: OMe; Cel mance Kenton “2 Wi locality, M. White, 28 July 1898 (NY). Major Co.: bare old road near Cleo, Stevens 1747 (GH, NY). Payne Co.: Stillwater, Brillhart 123 (TEX). Oklahoma Co.: prairie 2 mi N of Bethany, gh soil, Bb ter 1693 (NY). Harmon Co.: abandoned eld near Hollis, Stevens 1119 (GH, POM). iS Comanche Co.: Ft. Sill, Clemens 11652 (CAS, GH, MO). Murray Co.: 5 mi S of Sulphur, roadside, Waterfall 12293 (RSA, TEX). Marshall Co.: 3.5 mi W of Kingston, gravel-clay bed of Buncombe Creek, Goodman 6918 (RSA, SMU, UC). Bryan Co.: near Durant, Blain 86 (US). TEXAS. Randall Cr mer Walker Tank, SW of Spur, green f dried-up stream, Erlanson oy ICH ). Knox Co.: 1 mi E of ee ori clay roadside, Shuies 20794 (SMU). Cla oe 11.8 mi NW of H ; brown sandy silt and gravel between xsersted and railroad, shainers 15227 (SMU). Grayson Co.: nison, 725 ft, Letterman 70 (F, , NY). Jack Co.: 10.5 mi ENE of Jacksboro, sandy clay road mri “igegos ners 19012 SMU). D n Co.: Denton, sandy loam, McCart 8913 (TE : along Later near Plano, Lundell & Lundell 9307 (LL, MICH) Shackel- f G of S entrance to Ft. G tate Park, road shoulder, eens e 16438 (MICH, NY, SMU, UC, ob D : - ropping limestone, Lundell 11571 oon US, TEX Stanton. saiaty ground, Eggert, 13 June 1900 (MO). Howard Co. pring, Tracy 8298 (BM, F, GH, MO, MSC, NY, rex, US) Mitchell on AS rado, dry ound, E. J. Bis bvealhocally soil, open ground, E. J. Palmer 34590 (MO, NY, PH). 144 DUNCAN M. PORTER Taylor Co.: Camp Berkeley, disturbed rocky soil, Tolstead 7688 (GH, LL, xX . Eastland Co.: Ranger, Robinson 49 ( GH, TEX). Hood Co.: Granbury, E. J. Palmer 6517 (F, MO, POM). Ellis Co.: 1 mi W of Ennis, dry sandy soil, Shackelford 24 (SMU). Gregg Co.: without locality, C. L. York, summer 1941 (GH, TEX). Loving Co.: along highway ca. 3 mi Cory 58088 (SMU). Hamilton Co argin E side of Hico, gray-brown silt and limestone gravel, Shinners 15937 (SMU). McLennan Co ac roadside sand, D. Smith 805 ( ). Navarro Co.: Frost, Mitchan 45 ; be ‘ Ss (TEX). El Paso Co.: El Paso, Tharp 3541 (TEX, US). Hudspeth Co.: between Nulo and Harris Siding, Ferris & Duncan 2449 in part (CAS, MO, NY). Culberson Co.: near creekside 6 mi NE of Pine Springs, limestone hills, Waterfall 5768 (GH, MO). Reeves Co.: roadside 14 mi SSE of Orla, fine sandy silt, Shinners 31060 (GH, SMU). Ward Co.: 2 mi W of Pyote Air Base, gypsum flats, Waterfall 5492 (CAS, GH, MO, NY). Crane Co:: 13 mi ] 8058 (F, GH, MICH, MO, NY, TEX, U ) 13 mi S of Sheffield, cedar-sotol mesa-top, 2750 ft, Webster 400 (TEX). Crockett Co.: 15 mi N of Juno, limestone soil, 1500 ft, Warnock ¢+ McBryde 15178 (LL, TEX). Sutton Co.: Roy Hud. y silt, de , Salazar rt 8366 (ARIZ, LL, SMU, Atasec dry roadside ditch 1 mi SSE of Pleasanton, black silty clay, Shinners 24099 (SMU). Karnes Co.: Kam City tery, oam, Johnson 1055 (SMU, TEX). Goliad Co Goliad, sandy prairies, Williams 36 PH). LaSalle Co.: State Highway 97, 2 mi W o geles, gray cal- careous marl, Gongora, Garza ¢> McCart 8508 (SMU, TEX). M. i Co.: 8 mi E of Tilden, gray silty clay and limestone gravel, Shinners 16971 (SMU). Webb edo, Palmer 131 in (F, NY, US) art : ; berg Co.: Kingsville, dry neglected soil, disturbed areas, Bogusch 11845 (US). Zapata Co.: State Highway 496, 5 mi NE of Bustamante, sandy loam THE GENUS KALLSTROEMIA 145 Garcia, Esquivel & McCart 55 (SMU). MISSISSIPPI. pea Co.: Mississippi Agricultural College, Pollard 1295 (GH, MO, N MEXICO. SONORA EX 10, : e Cedros, flats, Lloyd 178 (US), SAN LUIS POTOSI: po pee. tev | 1024 (MICH). AGUASCALIENTES: Aguascalientes, Hart BM). GUANAJUATO: roadside ditch 14 mi NW of Salamanca, na Waterfall & Wallis (F, snl gene near Se, Fr. Basile U6, 162 PERU. HUANUCO: long tal near Huanuco, ca. 7000 ft, Macbride & Featherstone soe (F). LIMA: near Lima-Oroya highway at km 70 E of sandy soil, 2000 m, Stork, Horton & Vargas C. 10527 (U COMMON NAMES. It is surprising that such a widespread plant has so few common names. Those that have been reported are Carpet Weed (Texas ); Contrayerba (Arizona); Golondrina (Chi- huahua); Guesillos (Texas); Jepo (Peru); and Ray Weed ( Texas). TAxONOMY. The name Kalstroemia laetevirens has been applied to somewhat larger than average and upright specimens from Arizona and New Mexico, but these individuals simply represent one extreme in the variation to be found in K. parviflora. VARIATION. In addition to the variation in size alluded to above, there may be a considerable amount of variation in the species in terms of leaflet number (three to six pairs), sepal length in fruit (from extending only to the tops of the mature mericarps to the base of the stigma), beak length (from as long as to three times the length of the fruit body), and beak pubescence (trichomes ap- pressed to spreading or absent ). However, these characters appear to vary independently and show no ecological or geographical correlation and cannot be used in defining subspecific taxa in this somewhat variable species. Specimens of Kallstroemia parviflora from Peru show a certain amount of variation in flower size and sepal and style length, but 146 DUNCAN M. PORTER this variation is not nearly so wide as that found for the species in North America. RELATIONSHIPS. The close relationship of Kallstroemia parviflora and K. grandiflora was first indicated by Norton. The differences between these two species are discussed above. 17. Kallstroemia hintonii D. M. Porter, sp. nov. ¥PE: Mexico, Michoacan: ee District, Tepalcatepec, elev. 400 m, woods, fl. Digpe 7s ellow, 25 Aug. 1938, Geo. B. Hinton 12106 (anuz, holotype; ; Te ‘Us, i isotypes This : species is asined for r George Boole Hate Sr. e 1883 1943), mining engineer and well-known collector of the flora of Mexico a (raro perennis?); caules aap ad 4 dm longi vel longiores, aie, Gieharess lutea, et sericea, trichomata alba, antrorsa; ma ulae 5-11 mm longae, 1-2 mm Iatae; folia elliptica, 2. 5-8.5 ¢ m longa, 1 cm lata, pares — 5-7, foliola elliptica vel ovata, appresse hirsuta, 9-19 mm longa, 3-8 mm lata, pares in medio laminae maxima; peduncu uli quam folia subtendentia multo egy ah — ergo folia excedentes, - apicem vix incrassati, anthesin 3-10.5 cm longi, in fruct 0. cad recti et patentes; flores pentane 3 in i deeate ro 3-6 al sepala Cand , 8-12 mm longa, 1.5-3 mm lata, persistentia, quam petala 1/2 Co hissuta. trichomata lutea, oP IS stylum excedentia, in fructu mericarpia amplectentia, quam basin stigmatis longa, margines scariosi, deinde involuti, persistentia; petala alba, deinde luteola, in siccis aurantiaca, ad basin iateo-vit idia ve . raro rubra, obovata, truncata, ad apicem irreg- ulariter erosa, 15-30 mm longa, 9-20 mm lata, marcescentia; stamina et stylus aequilongus; filamenta ad basin alata; antherae ovoideae, in diametro 5-2 mm, rubro-aurantiacae sicut pollen; ovarium ovoideum, glabrum, 1-2 6 ovoideus, 4-5 mm 6-8 mm la tus, glaber; rostrum 8-11 mm longum, quam ora Pan longius, cylindricu um, ad basin , glabrum; mericarpia 5 alta, 2 mm lata, shakiatives rugosa, latera foveolata, adaxi- aliter Hy lane al Laniasecaitie gaewenls stems paige to 4 dm long or longer, ebeeaty with yellow and sericeous with w apically-directed trichomes; stipules 5-11 mm long, 1-2 mm wide; Noses elliptical, 2.5-8.5 cm long, ou i ane ig i i Ww Pac ai lange ae ser in flower, in fruit clasping but not entirely cov- ering mature mericarps and reaching to stigma base, only scarious margins becomin involute, persistent, satals white, yellowing with age and drying orange, base yello lh, or rarely red, obovate, truncate, apex irre arly notched, 15-30 mm 9-20 m wit marcescent; cent; st as long as style; filaments Stopes at base; anthers ovoid, pte in diameter, th and pollen red-orange; ovary ovoid, glabrous, 1-2 in diameter; style 6-9 Laie long, etiedioek base conic: cal, glabrous; biome clavate, 10-ridged, THE GENUS KALLSTROEMIA 147 ca. 1 mm long; fruit broadly ovoid, 4-5 mm high, 6-8 mm wide, glabrous; beak 8-11 mm long, ca. twice length of fruit body, cylindrical, base conical, labrous; merica 5 mm high, 2 mm wide, abaxially cross-ridged an slightly keeled, sides pitted, adaxial edge slightly angled. Fig. 17a, 17b. Map 11. FLOWERING DATES. Known to flower in August, September, and December. DISTRIBUTION AND HABITAT. Found along roadsides at elevations from 300 to 400 m in the general vicinity of Apatzingan, Micho- acan, Mexico (Map 11). Kallstroemia maxima and K. pubescens are known to occur in the same area. DISTINGUISHING CHARACTERISTICS. Kallstroemia hintonii is easily recognized by its combination of prostrate stems, elliptical leaves, five to seven pairs of appressed-hirsute leaflets, fruiting peduncles 5-104 cm long, extending the flowers well above the herbage, white flowers (petal bases yellow-green or red) 3-6 cm in di- ameter, hirsute sepals clasping the mature mericarps but not entirely covering them and reaching to the stigma base, the fila- ments winged at the base, red-orange anthers and pollen, cylin- drical style three or four times as long as the ovary, clavate ten-ridged stigma, broadly ovoid glabrous fruit 4-5 mm high and 6-8 mm wide, beak about twice as long as the fruit body, and abaxially cross-ridged and slightly keeled mericarps about 2 mm wide. Kallstroemia hintonii is unlikely to be confused with any other species of the genus. SPECIMENS EXAMINED. MEXICO. MICHOACAN: roadside near Apatz- ingan, 1000 ft, Barr, Dennis & Hevly 62-654 (ARIZ); wm Ss: of mi E tr os towar uacana, edge of raised road, 310 m, Porter 1414 (GH); dusty roadside 13 mi E of Cuatro Caminos, rocky valley alluvium, 310 m, Porter 1413A (GH). VARIATION. Petal color in Kallstroemia hintonii varies from white aging to yellow to white with a red basal spot. The collections Porter 1413A and Porter 1414 are rather depau- perate, but in all morphological respects they appear to be proper- ly placed in this taxon. RELATIONSHIPS. Kallstroemia hintonii shows no close morpho- logical relationship to any other species in the genus. 148 DUNCAN M. PORTER EXCLUDED SPECIES Kallstroemia Aiecidans (R. Br. in Sturt) Engl. in Engl. & Prantl, Nat. Pflanzenfam. 3(4):88. 1890. = Tribulopis angustifolia R. Br. in Sturt Appendix 70. 184 Kallstroemia bicolor (F. Muell.) Engl. in Engl. & Prantl, loc. cit. = Tribulopis bicolor F. Muell., Frag. Phyt. Austral. 1:47. 1858. Kallstroemia pts ti. " Endl., ae apa Mus. Wein 1:184. 1836. = Tribulus cistoides L., Sp. Pl. 1: :387. Kallstroemia hirsuta (Benth. ) a on "Engl & Prantl, loc. cit. = Tribulus hirsutus Benth., Fl. Austral. 1:289. Kallstroemia “hystrix (R. Br. in es Enel. - Engl. & Prantl, loc. cit. Tribulus hystrix R. Br. in Sturt, op. cit. 69. Kallstroemia macrocarpa (F. —: in Benth, :) Engl. in oe & Prantl, loc. cit. = Tribulus macrocarpus F. Muell. in tae ge loc. Kallstroemia minuta (Leichh. ex nan) E ngl. in ee “& Prantl, loc. cit. = Tribulus sealer Leic =e ex B fag nei ue cit. 291. Kallstroemia penta andra ee turt) E gore in Engl. & Prantl, loc. Ce eerie ce pentandra R Hie turt, op. cit Kallst platyptera (Bonth,) ig in Engl ie Prantl, loc: cH. = Tribulus : platypterus erus Benth., op. cit. roemia ranunculiflora (F. all 5 Engl. in Engl. & Prantl, loc. cit. Tribulus ee F. Muell., op. cit. 38. allstroemia solandri (R. Br. in Sturt) Engl. in Engl & Prantl, loc. cit. 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Cienc es Runyon, E. H. 1930. Germination and establishment of Covillea. Carnegie nst. Wash. Yearbook 29:225-226. Saispury, E. J. 1942. The Reproductive Capacity of Plants. G. Bell & Sons, London. ——————— 1961. Weeds and Aliens. Collins, London Scuinz, H. 1895. Beitrage zur Kenntnis der pia i Flora. III. Bull. Herb. ae 3: bela Scuoiz, H. Zygo phyllaceae, pp. 251-252 in H. Melchior, ed., Engler’s Syllabi der Pflanzenfamilien. Ed. 12. Vol. 2. Gebriider “ traeger, Ber SCHWEICKERDT, = c 1937. An account of eo South African species of Tribulus Tourn. ex Linn. Bothalia 3:159— SHELFORD, V. E. 1963. The Roslasy of North ait th Univ. of Illinois Press, Ur pe SHREVE, F, . The dea of the Cape Region of Baja California. Macro ri toa: ———— 1942. a satis vegetation of North America. Bot. Rev. 8:195—- 246. ———————. 1951. Vegetation of the Sonoran Desert. Carnegie Inst. Wash. Publ. 591. Smupson, G. G. 1965. Mammalian evolution on the southern continents, pp. 211-234 in Simpson, The Geography of Evolution. Chilton, Philadelphia. SLOANE, Lah 1696. Catalogus Plantarum quae in Jamaica sponte proveniunt. Lo 1707. A Voyage to the ire Madera, Barbados, Nieves, S. Cristophers and Jamaica, with the Natural Hist story of the Herbs and Trees, Four-footed Beasts, Fishes, Birds, Insects, Reptiles, etc. of the Last of those Pg etc. Vol. L. London. Situ, A. C., & I. M. Jounston. 1945. A gh ank ee sketch of Latin America. PP. Ll 1B ini . Verdoorn, ed., Plants Plant Sciences in atin Am ica Botanica, Waltham, Ma ass. STANDLEY, P. C. 1928. Flora “of the Panama Canal Zone. Contr. U. S. Nat. Herb. Vol. 2’ te 1940. (Data on sg ws herbarium specimen of Kallstroemia pubescens sg GH: Standley A.S —_——— peo Flora of Guatemala. Fieldiana: Bot. . 24, Pe 5, Seiaee W. a 1957. Introduction. pp. 1-116 in C. Linnaeus, Species Plan- Vol. 1. Facsimile of the First Edition. The Ray Soci , London. STEBBINS, CG. 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A revisional study of the bees of the genus Perdita F. f Smith, with special reference to the fauna o the Pacific Coast (Hymenoptera Apoidea). I. Univ. Calif. Publ. Entomol. 91345439 ——_——— 960. A revisional study of the bees of the enus Perdita F i Hou of ea asia 34th Contr., Ist. Sess. Exec. Doc. No. 135. Wash- ington, —---- & A, Guay, 1838. A Flora of North America. Vol. 1 Wiley & tae ork. Tost, * 76 te 1980, ee de vida natural = = Pert. Inst. Interamer. Cienc. ot. Tec. No. 5, San José, Costa Vain, A. M., & P. A. Rypserc. 1910, once No. Amer. FI. 25:103-— WATERFALL, U. T. 1946. Observation on the desert um flora of South- of plants, chiefly Californian, with revisions of certain genera. Proc. Amer. Acad. 11: 191-148. ———————. 1889. Upon a collection of plants made by Dr. E. Palmer, in 1887, about Guaymas, Mexico, at Muleje and Los Angeles Bay in Lower California, and on the Island of San Pedro Martir in the Gulf i . 24: 2. bi dag nage VAN Sn 1883. Surinaamsche Planten en Cultuurgewas- Boomen en Houtsoorten. Amsterdam Wana: R., & G. A. W. Arnott. 1834. earns Florae Peninsulae Indiae nian Vol. 1. Parbury, Allen, Lon don Wiis. L. 1935. A new Kallstroemia from ‘Texas. Ann. Mo. Bot. Gard. Wricar. S: 1940. Breeding structure of populations in relation to speciation. Amer. Nat. 74:232-248. Younxer, T. G. 1 1965. Cuscuta. N. Amer. FI. Ser. 2, Pt. 4. Be au ee * a te CONTRIBUTIONS FROM THE GRAY HERBARIUM OF HARVARD UNIVERSITY Edited by Reed C, Rollins and Robert C. Foster NO. CXCIX THE SYSTEMATICS AND EVOLUTION OF PEREZIA SECT. PEREZIA (COMPOSITAE) By BERYL SIMPSON VUILLEUMIER PUBLISHED BY THE GRAY HERBARIUM OF HARVARD UNIVERSITY CAMBRIDGE, MASS., U. S. A. Issuep JANUARY 1, 1970 jel oa Sues o. pean es Hie as Ean Gad Pac Re CONTRIBUTIONS FROM THE GRAY HERBARIUM ~ OF HARVARD UNIVERSITY Edited by Reed C, Rollins and Robert C. Foster NO. CXCIX THE SYSTEMATICS AND EVOLUTION OF PEREZIA SECT. PEREZIA (COMPOSITAE) By Beryt Simpson VuILLEUMIER PUBLISHED BY THE GRAY HERBARIUM OF HARVARD UNIVERSITY CAMBRIDGE, MASS., U.S. A. ; 1969 Miss, thr MEE OT ine, YAN T 3 Wig THE SYSTEMATICS anp EVOLUTION or PEREZIA sEcT. PEREZIA (COMPOSITAE) BERYL SIMPSON VUILLEUMIER! INTRODUCTION Although the principle of geographic speciation is now consid- ered an axiom of modern evolutionary theory, few studies have been made which actually point out the geographical factors that have influenced it. The investigations which have been made dealt, for the most part, with relatively simple cases of islands and their floras and faunas. During the past six years, Dr. F. Vuilleumier and I have been engaged in a study of the patterns of speciation on a continental area—South America—and, in par- ticular, the flora and fauna of the high Andes. (See Fig. 1 for the major physiographic features of the Andean Cordillera.) Ulti- mately, we hope to combine evidence from vertebrate animals and diverse groups of Angiosperms. However, before much progress can be made on such a study, it is essential to have a basic knowledge of the species involved and how they are related. A survey of the literature on Andean plants indicates that it would be impossible to rely on previous publications. Only about 50 genera of high Andean plants have been thoroughly revised within the last 30 years (since the wide- spread acceptance of the Synthetic Theory of evolution). Most of these did not use modern concepts, and were based on inade- quate material. Therefore, it was found necessary to begin a series of detailed biosystematic revisions of Andean plants to provide the founda- tion for an analysis of speciation in the Andes, and to determine what barriers have led to reproductive isolation (splitting) of various taxa. This necessity for basic monographic work also created an opportunity to investigate the procedures and method- ology of taxonomy itself. The South American section of Perezia, treated here, is wide- spread in the Andean and Patagonian parts of the continent. Its center of radiation is in the central high Andes, and its origin was probably in temperate montane habitats. Figure 2 gives the distri- * Research Fellow, Gray Herbarium of Harvard University. 4 BERYL SIMPSON VUILLEUMIER CERRO TURUMIQUIRE. | CORDILLERA’ DE MERIDA: | SIERRA NE VADA DE ae ee DE LA COSTA a - i : - —— LF ae RIO "URIBANTE V VALLEY | PATIA AIR N EASTERN ANDES / q | lie” ~™CENTRAL ANDES: : | “WESTERN ANDES) | é 3 ies aes * song Mitel ee Ld Oe ae | Roe if ee Sy ciatuns RIO" MARANON BASIN. |; ’ ee ath | ZNUDO DE VILCANOTA , | | -ALTIPL A ANO. f' Pas } Sf r ) ¥ yale ~~ \~ SIERRA DEL CANON . et 2 DE ACONGUIJA | y~ Se i; ~< w An ¢ ie “sh | ee teas SIERF 8 DE CORDOBA Aegis SS Ber f | NSIERRA DE LA VENTANA jin ae ee es | : Fic. 1. The physiography of the Andes. A simplified presentation of the structure and divection of the major mountain chains which make up the Andean Cordiller THE SYSTEMATICS AND EVOLUTION OF PEREZIA 5 ' ¢2=P MULTIFORA GROUP “7772 P PUNGENS GROUP <— P COERULESCENS GROUP <= P MAGELLANICA GROUP < P RECURVATA GROUP v7. P PRENANTHOIDES GROUP... Fic. 2. Distribution of Perezia sect. Perezia in South — showing the area covered by each of the six species groups (see Fic. 16 for the species in a group). Numbers indicate the total number of species present at various Seas 6 BERYL SIMPSON VUILLEUMIER bution of the six species groups in the section and the number of species found at various places along the Cordillera. Moreover, Perezia belongs to a group of genera, the Nassauviinae (a sub- tribe of the Mutisieae ), which are all linked historically with the Andes. These combined aspects indicated that a detailed revision of Perezia sect. Perezia would provide a solid initial work on speciation patterns in the Andes, and an opportunity to study the applicability of various taxonomic methods for later work. To determine which of the modern techniques would be most productive in this taxon and probably also in allied genera, a series of methods, which are currently used in taxonomy were employed. Crossing experiments with high altitude perennials is impossible because of their specialized growth requirements (see Physiological Adaptations ). Moreover, the majority of species of Perezia sect. Perezia are very slow growing and do not form large populations. The five approaches productively used were: (1) gross mor- phology and anatomy; (2) palynology; (3) cytology; (4) chemo- taxonomy; and (5) numerical taxonomy. These were pursued as independently and objectively as possible. From each, a partial or fairly complete taxonomy was generated, which could then be compared with, and evaluated in the light of, information pro- vided from other methods. The data were finally integrated and used to produce a synthetic picture, providing a background for the construction of a biologically meaningful classification which would reflect the speciation pattern of the group. ACKNOWLEDGEMENTS enerously given me help during the course of this study. I do wish to acknowledge especially the guidance of O. T. Solbrig, R. C. Rollins, C. E. Wood, Jr., B. G. Schubert, and R. A. Howard. D. Moore, R. Hoover, W. E. Niles, and L. Gottlieb all kindly sent seeds of Perezia, Both P. H. Raven and L. Sneider D aphtae unpublished chromosome counts and R. Foster wrote the Latin sue E. Minkoff and W. rt were patient enough to teach the methods and principles for the section on numerical taxonomy. I am particularly grateful to F. Vuilleumier whose continuous advice and help made completion of this work possible. n South America, A. L. Cabrera, M. Ricardi, P. Legname, and O. Tovar all accompanied me on field trips. Gracious hospitality was also extended by numerous other individuals and institutions including: F. Behn; C. Mufioz P., Universidad de Chile; O. Boelcke; A. Willink, A. Digelio, T. Meyer, and P. Legname, Instituto Miguel Lillo; A. Cabrera, Universidad de La Plata; R. Ferreyra, O. Tovar, H-W. and M. Koepcke, Universidad de San Marcos; THE SYSTEMATICS AND EVOLUTION OF PEREZIA 7 I. Kaplan, C. Bonifaz; J. Haffer; W. Say Phelps, Jr.; and A. Benevides and the Cerro de Pasco Corporation of P During the three years of this oly. f I was supported by a tga ip from er the NDEA-IV program. Funds for the use of the _—— were supp lied by expenses for two field trips were pe by grants lg Bourse fédérale de Fernald Fund of Harvard University; and NSF Grant 316 e Evolution- ary ae fboxcliane a t8 of the Department of Biology of Harvard Universi vy 8 aero of the Goode Base Maps, University of ned in numerous herbaria in Europe, South America, and ia nit ted. States yor I thank the staffs of these institutions for their caiy os generosity in lending material. The abbreviations used in the citation oe ens are those listed in Index Herbariorum rr gedonde and Stafleu, Because distribution a are given here for each species, the specimens cited following each species description are merely representative and do not constitute all the material examin aa: The type species listed in the synonymy are not relisted in the representative specimens. Except where specifically noted to the contrary, all types cited have been Seauiaat examine on HISTORY OF THE GENUS In the last part of the eighteenth and early part of the nine- teenth century, Europeans were actively exploring the New World for both economic and scientific purposes. Specimens of new plants and animals were constantly being sent back to Europe for identification and description. Sometimes, new genera or fam- ilies were created for the species which came from the Americas, while in other cases, the new taxa were fitted into European or African genera familiar to Old World naturalists. In the mid-1770’s, Forster, Banks and Solander brought back from Tierra del Fuego a small, delicate, white flowered Com- positae, which later fell into the hands of Linnaeus’ son who placed the species (now Perezia magellanica) in Perdicium L., a genus of African Compositae. In 1790, Vahl described, in the same genus, three other species (Perezia lactucoides, P. recurvata, and P. squarrosa) collected by Commerson on the voyage of de Bougainville. Humboldt, during his travels a few years later, col- lected three species of Compositae in Ecuador (P. pungens, P. multiflora, and P. pinnatifida) which he decided in 1809 belonged in Chaetanthera, a Ruiz and Pavon genus based on Peruvian collections. It soon became evident that the number and rate at which new 8 BERYL SIMPSON VUILLEUMIER species, genera, and even families were being described necessi- tated a thorough examination and revision of the existing tax- onomic system to rectify the confusion that had resulted. Alphonse de Candolle was one of the Europeans early to begin a complete reordering of the plant kingdom. Moreover, he was particularly interested in the Compositae and published numerous memoirs on the different “families” (tribes) of the group. In 1812, de Candolle published his third memoir, which dealt with a new assemblage of ligulate Compositae, the Labiatiflorae. He felt that this “be- longed between the Cichoraceas and the Cinarocephales” (now included in the Carducae ). Although he published the memoir in 1812, he had previously presented the material in a lecture at the University of Geneva in 1808. Between the time of his original dissertation and the published treatment, de Candolle had found a letter from Marius Lagasca in Spain to the then deceased Bonpland in Paris. It contained the results of a completely independent study he had made on the same group of Compositae that de Candolle had placed in his Labiatiflorae. Despite the fact that Lagasca called his group an “order,” the C haenanthophorae, and used different characters from those employed by de Candolle, the two schemes were very sim- ilar. However, the nomenclature of the Spaniard differed from that of his Swiss contemporary. Because such similar results had been arrived at by both bota- nists, de Candolle felt that the two studies should be published jointly. He wrote to Lagasca to suggest combining their efforts. Spain was in civil war at the time and Lagasca never received the letter. In 1812, after waiting several years, de Candolle pub- lished alone but he paid tribute to Lagasca’s work by incorporat- ing into his own account much of the nomenclature used by Lagasca in his letter to Bonpland. Ironically, Lagasca, isolated in Spain, had published his system in 1811 oblivious to the parallel work being carried on elsewhere. Even more ironically, Lagasca had changed much of the nomen- clature from that proposed in his earlier letter to Bonpland. For example, he had indicated that he was going to erect a genus Clarionea based on the tiny Fuegian Perdicium magellanicum. In his published study, the genus was circumscribed, but the name was changed to Perezia in commemoration of Lorenzo Pérez, a former pharmacist from Toledo, Spain. De Candolle, in his THE SYSTEMATICS AND EVOLUTION OF PEREZIA 9 attempt to give credit to Lagasca’s work, had used his name, Clarionea, for the genus based on Perdicium magellanicum. Thus the name Clarionea (and several others employed by de Candolle and attributed to Lagasca) became superfluous immediately upon publication. Yet, because of de Candolle’s world-wide influence and prestige, and because of the lack of a nomenclatural code, the name Clarionea was widely used and persisted until almost the turn of the century. During the next few decades, many more Compositae from South and Central America were described—some obviously closely related to the species initially placed in Perezia. Instead of realizing that the new species were congeneric with Perezia, European botanists were prone to create new genera for them. For the South American species now considered to belong in Perezia, Cassini erected Drozia, redefined Clarionea, and recog- nized Perezia and Homoianthus. The last is a genus of de Candolle which included three species from Ecuador As early as 1830, Lessing realized that all the South American members of this alliance belonged to the same genus and united them under Perezia. However, his treatment of the genus was not taken up by any botanist except Weddell (1855) until Bentham and Hooker (1873) followed it in the Genera Plantarum. Bentham (1873) went even further than Lessing and placed all of the North American species of the genus Acourtia into Perezia. Asa Gray (1883, 1884) followed the generic circumscrip- tion of Bentham and Hooker, but divided the genus into two sections: sect. Perezia (Euperezia of Gray) in South America and sect. Acourtia in North and Central America. After the influential works of Bentham and Hooker and of Gray, the circumscription of Perezia remained constant. The only changes involved the addition of new species as they were described. There has never been a thorough, systematic study of the genus, but several local floristic treatments of the South American species are available (e.g., Pert, Tovar, 1955; Pert and Bolivia, Weddell, 1855; Paraguay-Brazil-Uruguay, Baker, 1884; Argentina, Cabrera, 1939; Chile, Reiche, 1905). Rimo Bacigalupi published a revision of the North American section Acourtia in 1931 which included a detailed history of the genus, emphasizing the species of that section. The reader is referred to that study because Bacigalupi’s presentation needs no 10 BERYL SIMPSON VUILLEUMIER elaboration, and because the present work is concerned with the South American species of sect. Perezia. GENERIC RELATIONSHIPS The Nassauviinae is the extratropical, predominantly Southern Hemisphere subtribe of the tribe Mutisieae, to which Perezia belongs. Since this subtribe has been so little studied, a brief look at its constituent genera and their relationships might help to place Perezia in a more complete frame of reference. Historical Treatment. A nucleus of the genera now placed in the Nassauviinae were first grouped by Lagasca (1811) as the first “section” in his “order” Chaenanthophorae. The presence of all bilabiate corollas and tailed anther appendages were his diag- nostic characters for the section. Cassini (1817) also considered that this group of genera consti- tuted a natural assemblage, and he first applied the name “Nas- sauvieae” to it. However, it was not until 1821 that Cassini formally circumscribed the group as a tribe. Cassini considered the bilabiate corollas and the tailed anthers to be important tribal characters as did Lagasca, but he stressed the truncated style branches as the single most unifying character. Cassini’s circum- scription is essentially that which is recognized today, although it has been considered a subtribe since its rank was changed by Bentham in 1873. In addition to making the Nassauviinae a subtribe of the Mutisieae, Bentham greatly reduced the number of genera rec- ognized by Cassini, and even went as far as to place Cleanthes D. Don in synonymy with Trixis R. Br., a taxonomic judgment for which I can see no basis. Bentham’s main guides to relation- ships within the Nassauviinae were that Nassauvia was closely allied to Triptilion, and that Proustia (which he replaced in the subtribe) was close to Perezia. Macrachaenium and Leucheria were placed first in his scheme because they most closely resem- bled Chaptalia, a genus in the less specialized mutisid subtribe Gerberineae. Bentham also mentioned the similarity of some genera of the Nassauviinae to members of the Senecioneae, but he did not suggest that the latter tribe was more primitive than the Mutisieae. Small (1919) rarely discussed the relationships of the genera THE SYSTEMATICS AND EVOLUTION OF PEREZIA hi within the different tribes of the Compositae because he was primarily concerned with the phylogeny of the tribes themselves. In his evolutionary scheme of the Mutisieae, however, he did consider the Nassauviinae the basal, or most primitive, subtribe. In addition, he considered Trixis to be the least specialized of any genus in the Mutisieae, a view which has since been shown to be completely incorrect (Carlquist, 1957). Hoffmann’s treatment in Die natiirlichen Pflanzenfamilien (1893) did little to improve the taxonomy of the subtribe. Like Cassini, he excluded Proustia from the Nassauviinae solely on the basis of its round style-branch tips. However, he did recognize Cleanthes as a genus distinct from Trixis. His arrangement of the genera in the subtribe seems in no way to reflect a phylogenetic ordering, but rather follows the order in which he separated the genera in his key. The first modern attempt to assess the relationships within the Nassauviinae was in a study by Wodehouse (1929a). On the basis of pollen morphology, Wodehouse concluded that Proustia did indeed belong in the Nassauviinae and was closely related to Perezia. The pollen evidence also indicated to him that both Trixis and Jungia were isolated genera in the tribe. Nassauvia and Triptilion are similar to one another palynologically as they are morphologically. Wodehouse treated the remaining genera as a rather loose assemblage in which it was hard to determine rela- tionships on the basis of pollen morphology. In contrast to Small (1919), Wodehouse (1929a) concluded that the genus Trixis represented the culmination of a phylogenetic trend in the Mu- tisieae. Discussion. Because of the conflicting opinions of former authors, I have made a preliminary study of the different genera in the Nassauviinae. My conclusion is that Bentham (1873) and Wodehouse (1929a) were justified in including Proustia in the Nassauviinae. It is considered to be closely allied to Perezia, especially to the section Acourtia. On the basis of habit, anatomy, morphology, and cytology, it appears that Proustia and Perezia section Acourtia are more similar to one another than the two sections of Perezia are to each other. However, alteration of the present circumscription of Perezia must await further study. The following morphological similarities of Proustia to the genera of the Nassauviinae, and Perezia sect. Acourtia in particular, should 2 BERYL SIMPSON VUILLEUMIER be noted. Although Proustia does have rounded rather than trun- cate style-branch tips, it has the same type of anther tails, terminal anther appendages, and homomorphic capitula of bilabiate florets, unique to the Nassauviinae. There is a tendency for the style- branch tips of some nassauvid species to appear rounded (e.g., Perezia nutans) indicating that the apex shape of the stylar branches may have been overemphasized in the past as a charac- ter for separating higher categories. The habit of some species of Proustia is also very similar to that of various species of Trixis and Perezia sect. Acourtia. A particular type of brown “wool” occurs in the leaf axils and on the caudices of both Proustia and Perezia sect. Acourtia, but never on any parts of the plants of Perezia sect. Perezia. Finally, the pappus, while normally setose in both Perezia and Proustia, has a tendency in some species of Perezia sect. Acourtia and Proustia to become thickened at the apex of individual bristles. A few other personal observations about the subtribal taxonomy might be mentioned. First, Cleanthes should be kept distinct from Trixis as in Hoffmann’s treatment; second, the monotypic genus Ameghinoa, described in 1897 after the works of Bentham and Hooker (1873) and Hoffmann (1893), is placed in synonymy with Trixis. The gross morphology and pollen shape indicate that A. patagonica is merely a specialized Trixis. The position of another monotypic genus, Cephalopappus Nees & Mart. is particularly hard to determine because it is apparently very rare, and the original description and accompanying illustra- tion are confusing. I have not seen a specimen of this species and therefore it is impossible to comment on its affinities. On the basis of this preliminary survey of the subtribe, it would be presumptuous to attempt to draw positive lines of relation- ships between the different genera. There are undoubtedly sev- eral distinct evolutionary lines within the Nassauviinae, and obviously there has been considerable mosaic evolution. The subtribe appears to contain a natural group of genera (except per- haps for Cephalopappus and Leunisia) which arose from a com- mon ancestral stock, and which can be grouped into clusters of genera. Future detailed anatomical, morphological and cytological work should refine the relationships within each of these. As noted by many workers who have dealt with the Nassauvii- nae, Nassauvia and Triptilion constitute a very closely related THE SYSTEMATICS AND EVOLUTION OF PEREZIA 13 unit within the subtribe. Jungia (incl. Pleocarpus) stands some- what isolated in the subtribe and is more similar to Trixis than to most of the other genera. Leunisia is an even more isolated genus, but again shows some slight resemblances to Trixis. Leucheria and Perezia sect. Perezia appear to be related and both are morphologically somewhat in the middle of the remaining genera because of their inclusion of such a wide spectrum of types. Both contain species that are small, monocephalous and scapose, and species that are robust, tall, leafy, having polycephalous flowering stems. Genera such as Macrachaenium are similar in morphology to the scapose species of these two genera whereas Polyachyrus, Cleanthes, Pamphalea, and Mosharia are most similar to the cauline, polycephalous species. KEY TO THE GENERA OF SUBTRIBE NASSAUVIINAE A. Capitula with 2-5 florets, (B). B. Capitula with two dimorphic a gietsg SEA Polyachyrus Lag. B. Capitula with 4-5 monomorphic florets, (C). C. Pappus simple ‘etiea. Lay "lanceolate, usually more than gisties Per Doe Oe ea eee ie assauvia Juss. C. Pappus si, ahr feathery at the apex or com>, 3 pappus PRIN CO Ng So ida cat ie Triptilion Ruiz & Pav. A. Capitula with more than 6 florets per on pein (D). D. Receptacle with numerous paleae, (E E. Paleae a narrow cylinder enclosing each floret ...... Jungia L. f. E. Paleae of the outer florets a cup-like aoe around the ister rai os AO ct kag MSA a i ae og Moscharia Ruiz & Pav D. epee without Sane or with only a few scattered at the margins of the receptacle F. Plants covered al woolly or silky white trichomes, (G). . Leaves reduced to three-parted spines . . Ox xyphyllum Phil. G. Leaf — flat, without sharp spines H. Leaves with ex tremely long petioles pappus fine, rae i achaenium Hoo it Sage g ee eae a oe piney | eucheria Lag. F. Plants glabrous or with scattered multicellular giandulr trichomes. Woolly trichomes sometimes present in the | eaf axils or on the caudex, (J). }. Involucral bracts narrowly lanceolate, Rea? ite outer and inner equal in length; florets bright yellow, (K K. Achenes with glandular trichomes with a prominent, bulbous apex, clear in color ........................ Leunisia Phil. K. Achenes with glandular trichomes without a swollen apex 14 BERYL SIMPSON VUILLEUMIER ta eye ah beta Trixis R. Br. (including Ameghinoa Speg. ) J. Bracts pale green, dark green, or reddish, often scarious along the margins, outer frequently shorter than the inner; florets blue, white, or pink (pale yellow in some species of Perezia), L (L). Ay NO NON oo ess ides ae L. Pappus present, ( Styl Pamphalea Lag. , (M). . Style-branch tips rounded .............. M. Style-branch tips truncate, (N). . Rows of involucral bracts in three or fewer series; capitula very hemispherical; achenes densely pubes- cent; caudex glabrous, (O). O. Capitula shorter than 6 mm; pappus setose Cleanthes D. Don. O. Capitula longer than 6 mm; pappus tending toward, or actually, plumose .... Leucheria Lag. - Rows of involucral bracts in usually more than three series, scarious; capitula hemispherical or turbinate; tufts of brown wool often present on the caudex Perezia Lag. Proustia Lag. oe TREATMENT OF MORPHOLOGICAL CHARACTERS OF PEREZIA To standardize data collecting from herbarium specimens, a data sheet was prepared containing recordings of all pertinent characters, both numerical and non-numerical, for over 1200 specimens. Each specimen was given a reference number when it was examined. The collector, his number, the date and place of collection and the herbarium which housed it were recorded, making it possible to relocate the specimen from its reference number. The altitude, latitude and longitude of the collection locality were also recorded. All meristic characters were measured across the broadest area for width, and down the longest part for length. The 24 numerical characters measured or counted, and the 23 non-numerical characters recorded are listed in the left- hand column of Table 1. The data were punched on IBM cards, using numbers or letters as shown in the right-hand column of Table 1. Non-numerical characters were not given numerical values as suggested by Sokal and Sneath (1963, p. 291) or Rogers et al. (1967) because it was felt that such a conversion was useless. Minkoff (1965) has shown some of the dangers involved in treat- ing non-numerical characters statistically when they are assigned arbitrary numerical values. In this case, the non-numerical charac- ters were represented by letters facilitating the card punching and THE SYSTEMATICS AND EVOLUTION OF PEREZIA 15 making it easier to recall the character state for which they stood. Using these data cards, a series of computer programs were run, designed to provide a variety of information about the speci- mens, populations and species. In the programs described below, the specimens were grouped into populations or species before the program was run. The first program was a simple one, written to arrange the numerical characters in ascending order for each species. A list was printed for each character, containing the lowest to highest value of that character for the species being dealt with. The speci- men reference number appeared next to the value to which it corresponded, making it possible to find the specimen having the lowest, highest, etc. value for that character. This character ar- rangement program was useful as an aid in writing species descriptions. Each range of measurement for a certain character in a species description represents the observed range for all speci- mens measured. An advantage of the values being printed in ordered sequence is that it was possible to see immediately whether or not there was a skewed or bimodal distribution of the characters within a species. In almost every case, the characters seemed to fit a normal distribution. The second program run was designed to find the means, standard deviations, and coefficients of variation for each charac- ter for each population of Perezia. Again, the specimens were pre-grouped beforehand. The purpose of this program was to find changes in the mean values of the characters from popula- tion to population within a given species, and to see whether such changes constituted a pattern in several species. These statistical procedures are standard in systematic biology (see Simpson, Roe, & Lewontin, 1960, Chapt. 6). Most of the useful information which came from this program is discussed under the species where it is pertinent. However, a few examples of the kind of information derived are given here. It was found that a similar pattern of variation in plant size existed in three sympatric species of Perezia (P. lyrata, P. prenan- thoides, and P. pedicularidifolia) which grow in the Nothofagus forest of southern Chile. In all species, the populations with the largest plants occurred in the area of the north-central part of the range. The average plant size in all of these species decreased 16 BERYL SIMPSON VUILLEUMIER slightly in northern, and then more sharply in southern popula- tions (Fig. 20). The part of the range in which the populations with the largest plants occurred coincided in the three cases. These findings suggest that there is an area of optimal growth conditions in the north-central part of the Valdivian forest for those species of Perezia adapted to the mountain slopes of the deciduous Nothofagus forest zone. Presumably, increased dryness in the north and increased cold in the south are influential in reducing plant size in these areas. In addition, this program was useful for showing the overlap present in a given character for different populations of a species, and provided the statistics necessary for a t-test for significance of the differences. In one case, two populations of Perezia pur- purata had been considered separate species because the head size in one was supposed to be smaller than in the other. Graph- ing the means and standard deviations of these and several other populations (see discussion, Part II under P. purpurata and Fig. 23) showed a large amount of overlap in the parameters for head size. A similar test for head length and head width was used for P. ciliosa. A modification of the same program was used in the palynolog- ical study discussed below. Calculations of the means and stand- ard deviations of the pollen grain diameters for the different species indicated that there is some consistency in grain diameter within a species group (Table 4), although the size differences between the groups were not significantly different. A third program was run to find the correlation, r, between all possible pairs of characters for each species. Species were pre- grouped for these runs, but in some cases subspecies or popula- tions were also run individually to find any correlations which might have existed in large, isolated populations. The significant probabilities for the correlation coefficients were taken from Table V of Simpson, Roe, and Lewontin (1960) and those corre- lations found to be significant at the .05, .01, and .001 levels were noted for further analysis. Correlation coefficients were also computed between meristic characters and altitude, latitude, and longitude. In general, very few statistically significant correlations were found between the numerical characters and any of the three geographical param- eters. The apparent absence of altitudinal effect could be due THE SYSTEMATICS AND EVOLUTION OF PEREZIA 17 TABLE 1. GROSS MORPHOLOGICAL CHARACTERS OF PEREZIA RECORDED! NUMERICAL CHARACTERS Character Order of Magnitude Specimen number 1-1500 Altitude 0-9000 Latitude —~6-60 ngitude Height of plant 1-99 a of seers 1-99 umber of stem leaves 0-99 wore of head 45-5 Length of head 4.5-5 idth of involucre 45.5 Len of involucre 45-5 Number of heads per aes 1-99 Number of heads per plan 1-99 Width of basal leaf 13.0-.1 Length of basal leaf 33.0—.3 Number of rows of bracts 1-7 Width of outer bract 1.5-.1 Length of outer bract 2.0-.1 Width of inner see 2.0-.1 Length of inner brac 4.0-.9 Percent scarious of outer veo 0-99 Percent scarious 0-99 Length * ae pth sa aes 45-5 Length of outer ligule 5-1 Length of pa eli 3.0-.5 Number of florets per head 9-82 NON-NUMERICAL CHARACTERS Color of corolla blue, white, violet, yellow, - ae ne magenta, 3 (B, rR oO; VU Description of stem leaf shape DLN thy oD pit ly- rate, ovate, spathulate, absent (L, N, > > > > Description of stem leaf margin entire, ciliate, serrate, dentate, pecti- nate (E, C, Description of stem leaf size small (less than 3 cm), Tf ( Lerentes than 3 cm), absent (S, L, A) 1 NOTE: If a character rigaie not be determined for a specimen, the space for that character was we blank value of zero on an IBM card meant that the value for a character was zero ieee o ds were used for each specimen of Pere. he order given here is not i order in which the data wer tually punched on the data cards, but is the order of rearranged data cards punched by the computer of numerical tate all measurements are in centimeters except altitude (in meters) and latitude and longitude (in degrees and fractions of ; minus degrees for north latitude). In the case of non-numerical characters, the letters in paren- eses were punched on the cards. 18 BERYL SIMPSON VUILLEUMIER NON-NUMERICAL CHARACTERS (cont'd) Shape of involucre Direction of head Shape of basal leaf turbinate, hemispherical, cup (T, B, Cc upright, nodding (U, N) spathulate, lanceolate, lyrate, linear, ovate, linear-lanceolate, oblanceo- late, obovate (SP, LA, LY, LLG, LL, ) Edge of basal leaf entire, ciliate, spin arted-entire, pa rted-dentate, ae -doubly di- ica dentate, serrate, undulate, lobed ee CI, SP, PE, PS, PD, DE, SE, » LO Surface of outer bract glandular ee punctate glabrous ) Surface of inner bract ace of basal leaf . Shape of outer bract linear, lanceolate, ovate, oblong, pan- urate, spathulate, circular, reni- form a Para ag (LI, LA, OV, OB, SP, CI, RE, OL) Tip of outer bract acute, sok mucronate, acuminate N Edge of outer bract pectinate, dentate, serrate, ciliate, en- tire, undulate, (PT, DE, SE, CI, Surface of achene glandular trichomes, double hairs, two kinds of trichomes, glabrous (G, S, Amount of achenal ——— ee dense, absent (S, A) Color of achenal pu . blond, aie Pat (Cy SB, ridged, aggre oe ae rei ng tri- , glabrous (R, Amount of receptacular pubescence Pow me, absent (D, : A Description of receptacle in part to the fact that limited elevation data were available. In addition, species of Perezia usually grow at fairly constant altitudes throughout their ranges. The lack of significant correla- tions between characters and latitude or longitude might result from the fact that only linear correlations are found using r. For example, the type of variation seen in the three Nothofagus forest species discussed above was not detected using the standard correlation coefficient. An exception to the general lack of correlation between geog- raphy and numerical characters was found in Perezia multiflora. Significant correlations were found between both longitude and THE SYSTEMATICS AND EVOLUTION OF PEREZIA 19 altitude and capitula length and width, leaf length, and the number of heads per peduncle. The correlations indicate that there is a cline in these morphological characters from the high northwestern part of the range to the low southeastern part. These correlations, with respect to the interpretation of the subspecies of P. multiflora, are discussed fully under that species. The use of correlations also emphasized the need, in some cases, to examine the size of an organ or part of a plant in the context of the entire plant. A group of populations included here in Perezia lyrata were previously considered to be a separate species because they had “larger capitula and larger outer bracts.” An analysis of the correlations showed that the larger capitula and bracts were correlated with an overall increase in plant size and merely represented one extreme of variation present in the species. MORPHOLOGY AND ANATOMY Habit. In both sections of Perezia, all species are perennial herbs although some species of sect. Perezia have been mistakenly described as annuals. The most common habit of the South Ameri- can species is a rosette with one monocephalous flowering stem but there is considerable variation of this basic type within the section. However, habit is quite constant within a species group, making it a useful taxonomic character. The habit of a species is also correlated with its ecology and, it should be noted, related species of a group tend to grow in the same, or very similar habitats (Table 2). There are five basic types of habit present in the South American Perezia. One includes tall, leafy plants with branched flowering stems and numerous capitula (PLATE 1-4). This growth form is found in both the P. multiflora and the P. prenanthoides species groups. In this case, the similarity of habit appears to reflect the retention of a primitive character from an ancient, rather than recent, common stock. Another habit type, common to the members of the Perezia magellanica species group, is a fairly compact basal rosette with one or several monocephalous flowering stems. Plants of this group grow singly in, or around, rock crevices (PLATE 1-5) where they receive protection from the cold and wind, 20 BERYL SIMPSON VUILLEUMIER TABLE 2. CORRESPONDENCE BETWEEN HABIT, HABITAT, AND SPECIES GROUPS ANDES LOWLANDS Central Southern | Patagonia montane slopes high slopes mountain peaks scrub steppe Uruguay open woods and grasslands high peaks “Alpine”? meadows — Tall grass — Dry, rocky scrub — Short grass Nothofagus forest Magellanic moorland Dry grass and Paraguay-Brazil- P. multiflora P. squarrosa P. kingii ie ae eel Ga P. prenanthoides P. nutans P. pungens L-A P. ciliaris L P. carduncelloides L Is P. carthamoides P. viscosa P. lactucoides : itera ea ace P. lyrat P. fonkii P. delicata rrr PF rPrPr P P. megalantha P. coerulescens : pinnatifida P. pygmaea P. poeppigii A-C P. linearis c P. recurvata Cc ama L=large, caulescent, many-headed plants R = tight, small rosette A = open rosette, usually one head/stem C= cushion plant THE SYSTEMATICS AND EVOLUTION OF PEREZIA 21 All of the members of the Perezia pungens group share a third, and the most common, habit type which is essentially a larger, more open form of the rosette found in the P. magellanica group. However, associated with this loose rosette are numerous flower- ing or slightly branched stems with several capitula. The fourth type of habit is the other extreme aspect possible for a rosette plant, i.e., a very reduced, compact rosette closely ap- pressed to the ground (pLate 2). Species with this type of habit belong to the Perezia coerulescens complex and frequently form mats of numerous plants crowded together at very high elevations. The last general habit type is restricted to the Perezia recurvata group which occurs in Patagonia. There is a tendency in the species of this group for plants to branch at the base and form a cushion type of aspect (PLATE 2-4). Although there is overlap in the different types of habit, the growth form of a species usually allows it to be placed readily into one of the species groups (Table 2). Often, the aspect of a specimen combined with one other important character, such as leaf shape or bract morphology, is all that is needed to identify a species. Roots and Rhizomes. All species of Perezia sect. Perezia have rhizomatous rootstocks except those of the P. multiflora species group, the three members of which have long taproots. Although woolly caudices and tuberous roots occur in the North American species, neither is found in sect. Perezia. Foliage. The basal leaves in species of Perezia vary in shape from broadly ovate to linear, sessile to petioled, and from entire to deeply and doubly lacerate. The shape, margin, and the base of the leaf are very useful in separating species. Although the leaf shape and margin are usually consistent with- in a species, Perezia pilifera exhibits a dimorphism for leaf shape. Most plants have fleshy, highly segmented leaves, each segment of which is terminated by a long, soft, white spine. Some plants, however, have entire linear leaves which are three-angled in cross section. These needle-like leaves sometimes have long white spines along the margins, and invariably are terminated by one. Individ- ual plants are always composed of only one leaf type, and fre- quently all of the plants within one population have the same leaf type. Until now, the two forms of P. pilifera were placed in oo BERYL SIMPSON VUILLEUMIER ah. ATE 1. Fic. 1-1 to 1-3: Capitula of the three closely related _—? of the Perezia pungens complex ae differences in the involucral bracts. 1-1. P. pungens. 1-2. tarts. 1-3. P. carduncelloides. All natural size. Fie. wi 1-5: Habit of two species. 1-4. P. prenanthoides. 1-5. P. lyrata. Both reduced about 10 x. THE SYSTEMATICS AND EVOLUTION OF PEREZIA TE 2. Fic. 2-1 to 2-3. The three closely related members of the Perezia coerules- 2-1. P. coerulescens (1/5 x); 2-2. P. 19 (3/4 x); 2-3. P. pin- cens complex: 2-1. natifida (about natur 24 BERYL SIMPSON VUILLEUMIER different species. In Bariloche, Rio Negro, Argentina, I found a population with both types of plants, even though the dissected leaf form was the more prevalent. Since intermediate leaf types do not occur, it is possible that the leaf shape is controlled by a relatively simple genetic mechanism, and the presence of homo- geneous populations (only one form present) could be due to establishment by a propagule with alleles for only one form. This type of colonization corresponds to the founder principle of Mayr (1963). A second species, Perezia recurvata, has three more or less rec- ognizable leaf types present in various populations. In this case, intermediate leaf types are common and variation is almost con- tinuous as shown in Fig. 28 and 29. The partial correlation of leaf type with geographical area (Fig. 27-4), and the presence of intermediates indicate that the present variation reflects former isolation, subsequent secondary contact, and recent gene flow. It appears that morphological changes, but not reproductive isolation, occurred during periods of separation. Clearings were made of the leaves of all species of Perezia sect. Perezia to determine the kind(s) of stomata, their distribution, the vascular patterns, and the types of trichomes. Preparations were made using the standard procedure of clearing in 1 per cent NaOH for 24 hours, dehydrating in a graded alcohol series, stain- ing in basic fuchsin, and placing in permount. All of the species except two were found to have ranunculaceous stomata liberally distributed over both leaf surfaces. Two species, Perezia linearis and P. recurvata, had stomata only in two narrow bands on the underside of the leaf next to the midrib. This reduc- tion in the number of stomata is presumably correlated with the xerophytic conditions of the Patagonian lowlands where the two species occur. Pyykké (1966) found a similar sort of stomatal restriction in species of other genera adapted to the Patagonian steppe. The leaf venation of all species investigated is basically reticu- late, but in some species such as Perezia pilifera and P. recurvata it is so reduced as to appear open. This open venation appears to be correlated with specializations for a xerophytic habitat. A similar situation was reported in Raoulia Hook. f. by Solbrig (1960). The venation pattern is not constant within one species, and in P. pungens and P. multiflora it can vary from densely THE SYSTEMATICS AND EVOLUTION OF PEREZIA 25 reticulate to almost open, depending on the ecology of the popu- lation. Foliar trichomes vary considerably in type, size, and density in different species of Perezia. No species has completely glabrous leaves although some species such as P. bellidifolia and P. lactu- coides appear glabrous unless carefully examined. Involucral Bracts. Bacigalupi (1931), in his treatment of the North American species of Perezia, correctly stated that the invo- lucral bracts were one of the most diagnostic characters in the genus. The bracts are free and arranged in several series increas- ing in size (generally) from the outside to the inside. The outer and the inner bracts vary considerably in morphology and are treated separately here although the intermediate series are trans- itional in size and shape. The specific characters of the species are primarily in the morphology of the outer bracts which differ in shape, margin, pubescence, color, and number. The outer series can range in morphology from stiff lanceolate, very sclerenchymatous and scarious bracts in one species, to soft, foliaceous, and non-scarious bracts in another. The margins vary interspecifically from entire to dentate or pectinate, and the apex from mucronate to obtuse. The inner bracts are consistently lanceolate with scarious margins. Capitula. The majority of the South American Perezia have monocephalous flowering stems which may, or may not, scapose. Species with polycephalous flowering stems may have the heads arranged in racemes or panicles. Where there is a branched, flowering stem, flowering begins with the ae (innermost) capitulum and proceeds downward (outward). I two species, P. nutans and P. multiflora, it appears that some heads never mature. Individual heads are upright in most species, but are nodding in a few. The capitula of all South American species appear radiate be- cause the ligules of the outer florets are longer than those of the inner florets. The amount of difference between the lengths of the outer and inner ligules varies in the different species. The capitula of Perezia magellanica are very radiate in form, whereas in other species they are barely so. Without exception, flowering within a head proceeds from the outside to the inside. Florets. As in most genera of the Nassauviinae, the florets of Perezia are bilabiate with the outer three petals fused into a 26 BERYL SIMPSON VUILLEUMIER tridentate ligule and the inner two petals free and curled. Blue is the most common corolla color and is found in 87 per cent of the species (26 of 30 species). Other colors, ranging from brown through crimson, magenta, pink, cream, white, and yellow also occur, and frequently several floret colors can be found on differ- ent plants of the same species. The corolla tube and ligule of all the florets in a head are mono- chromatic in the species of Perezia sect. Perezia except P. multi- flora. The ligule and the outer half of the corolla tube are either blue or white in this species and the inner two petals and inner half of the corolla tube are yellow. The effect of this dichromatic pattern is to give the capitulum the appearance of having blue (or white) ray florets and yellow disc florets. A few species, especially in the Perezia magellanica and the P. pungens alliances, have glandular trichomes on the corolla tube near the throat and on the ligule. In a few cases, the presence or absence of these floral trichomes has proved useful in separating species. The anthers of all species of Perezia have tails and terminal appendages like other members of the Nassauviinae. A brief survey of the comparative lengths of the anther tails in the various species of Perezia indicated that there were no meaningful size differences between species. Frequently, it has been noted that the anthers are brightly colored and form a contrast with the corolla. Bright deep blue, black, malachite green and pink anthers have been recorded by various collectors. The styles always have globose bases, terete stems, and re- curved truncate style branches. In some cases, as in a few speci- mens of Perezia nutans, the style branches were observed to be rounded and to approach the type found in Proustia. The styles are usually yellow, but blue and pink ones have also been re- corded. Small (1919) recorded that there was a mechanism for explosive dehiscence in Perezia multiflora. However, I have never noticed an explosive reaction upon touching florets of P. multiflora in the field. A few flowers of several species of Perezia have been found which had styles with three stigma branches. It has been noted that such abnormalities occur sporadically throughout the Com- positae (Bentham, 1873; Small, 1919) and seem to be teratological cases of no evolutionary or taxonomic importance. THE SYSTEMATICS AND EVOLUTION OF PEREZIA 27 Pappus and Achenes. A setose pappus is present in all species of the genus, varying in color from white to deep red-brown. The achenes are uniformly ellipsoidal in shape and incon- spicuously ribbed. Their surface is generally pubescent and the trichome type is frequently distinctive enough to allow determi- nation of the species group (Fig. 3, Table 3) but nothing more. The density of the achenial hairs is variable within a species and therefore unreliable as a character for the separation of species. Receptacles. The receptacles of the species of Perezia are of two types, fimbrillate and foveolate with a few scattered tri- chomes on the surface. When the receptacle is fimbrillate, tufts of long silky trichomes arise from around the points of achene attachment. These tufts of trichomes are usually associated with achenes covered with double hairs. The glabrous foveolate recep- tacles are usually found in species with glandularly pubescent or glabrous achenes. The receptacle type, therefore, shows the same correlations with species groups as does the achene pubescence type (Table 3). Trichomes. The types of trichomes found on plants of Perezia species fall into two broad categories: the double hairs or Zwill- ingshaare of Hess (1938) (Fig. 3-1 to 3-3), and glandular tri- le 4b 5 ” 40. , ay 3 Fic. 3. Trichome types of species of Perezia sect. Perezia. Types 3-1 to 3-4 are achenial trichomes, types 3-5 to 3-7 are foliar trichomes. Trichomes 3-1 to 3-3 are “double hairs’? and 3-4 to 3-7 are glandular hairs. 28 BERYL SIMPSON VUILLEUMIER TABLE 3. TRICHOME TYPES OF PEREZIA SPECIES! GLANDULAR FOLIAR ACHENIAL TRICHOMES ICHOMES TRICHOMES la Ic a es P. multiflora D M-D S P. squarrosa D S S P. kingii D S 5 P. prenanthoides D M P. nutans D M P. pungens S—-M S-D S sa a M M P. sublyrat S M-D | S—-M f. Fay 8a S S S P. ciliosa D S P. purpurata S-D S-D | S-D P. pilifer S P. carthamoides M-D S-M | S-M F: ea D D . lact M S F. pediulriifl D S—-M M P. lyrat D S-D..1 S—-M are? D M P. delicata D S P. magellanica D D P. calophylla D D P. bellidifolia D S P. megalantha D D D P. coerulescens S S S S-D P. pinna S D P. pygmaea S M-D S P. poeppigii M S S P. linearis M S S P. recurvata M M Ss poems 1 ape types are mmm in F Symb : S =sligh Cap » M= moderate amounts, D = dense chomes (Fig. 3-4 to 3-7). The double hairs are found on only the achenes and the receptacles, and vary from copper to white in color. The double hairs of the achenes have a specialized basal cell which is hygroscopic and is important for the fuctioning of the trichomes. The double hairs on the receptacle do not have a special cell at the base. According to Hess (1938) the double hairs have several func- tions: they aid in dispersal by acting as a second pappts ; they help to protect the achene from climatic and mechanical damage; THE SYSTEMATICS AND EVOLUTION OF PEREZIA 29 they help to secure the achene to the substrate upon which it falls; and they aid in the uptake of water. Hess postulated that double hairs were the primitive achene trichome type in the Compositae, and that substitution of another type of trichome, or loss of all hairs, represented advanced conditions. Within Perezia, Hess’ generalization appears to be true, as those species which are most specialized in habit and morphology are usually those with reduced amounts of double hairs, glandu- lar rather than double hairs, or glabrous achenes. This does not mean that a species with dense double hairs on its achenes is necessarily primitive. In Perezia, as in all organisms, evolution is reticulate, and different characters evolve at independent rates. Whether or not a species is primitive or advanced can be deter- mined only by taking all of its characters into account. Glandular trichomes are found on all parts of the plant body, but vary greatly in size and density. Their function, in addition to their generalized secretory ability (Metcalfe & Chalk, 1965; p. 783), has not been determined (at least in the Compositae ) and, as a result, it is difficult to ascertain the reasons for increases or decreases in the densities of glandular trichomes. From specimens alone, it appears that changes in the amounts of foliar trichomes of Perezia are ecologically controlled and highly unreliable as a taxonomic character. The glandular trichomes of a few species contain a reddish pig- ment which gives the bracts and stems on which they occur a red-purple cast. Marked quantities of these pigment-bearing tri- chomes have been found only in Perezia magellanica and P. pedicularidifolia. The red color of the bracts of other species is due to pigmentation of the epidermal, rather than trichome, cells. Drawings of the different types of achenial and foliar trichomes are given in Fig. 3. Table 3 lists the various kinds of trichomes found in the different species of Perezia. It is evident from this table that certain types are correlated with the groupings of species arrived at by the use of gross morphological characters. Although to a lesser extent, the foliar trichome types are also indicative of affinities between species (Table 3). The profitable use of trichomes in Perezia corroborates the conclusion of Drury and Watson (1965, 1966) that trichomes should be more widely and critically examined in systematic studies. An investigation of its trichomes was a major factor leading 30 BERYL SIMPSON VUILLEUMIER to the exclusion of Perezia lanigera from this genus. It has a completely different type of achenial trichome from any species of Perezia and it also has tufts of dense, woolly hairs in the leaf axils. Axillary trichomes have not been found in any South Ameri- can species of Perezia. DISTRIBUTION AND ECOLOGY Habitats. Twenty-seven of the 30 species of Perezia sect. Perezia are Andean, and 23 of these grow above timberline. The three extra-Andean species (one of which has a subspecies in the Andes) are centered in the open woods of the Paraguay-Uruguay-Brazil lowlands. The Andes themselves are covered by several major kinds of vegetation as shown in Fig. 4, each comprised of numer- ous microhabitats. Species of Perezia have radiated into almost every habitat now present along the Cordillera. A species is fre- quently limited in distribution by its habitat, and has a growth form correlated with it. Some relationships between habitat, habit, and species groups are given in Table 2. The high Andean chain above timberline is usually divided into two gross vegetation types: the humid, lush, paramo of Venezuela, Colombia, and Ecuador; and the dry, relatively barren puna to the south. The boundary between these two major zones is the northern distributional limit of the South American Perezia (com- pare Fig. 2 with Fig. 4), although two species, P. multiflora and P. pungens, encroach upon the paramo in Ecuador and extreme southern Colombia. The puna, where the majority of the species of Perezia are located, is actually a composite of arid valleys, grassy peaks, shrubby and thorny slopes, volcanic cones, and the windswept steppe of the altiplano (Fig. 4). In the south, begin- ning at about latitude 40°S, the peaks are covered with more humid, almost alpine, meadows. Two endemic species are found in the Nothofagus, or southern beech forest, in the southwestern part of the continent along the montane slopes. Several other species of Perezia grow into the forest, but are also found in open areas and along the forest edge. East of the southern Andes is the barren grass and scrub of Pata- gonia. Only one species is actually found on the Patagonian steppe, although a few others stray onto its western edge. Figure 4 also shows the Magellanic moorland at the extreme tip of the THE SYSTEMATICS AND EVOLUTION OF PEREZIA 4 Vy, eee _ wes param % i/o - oy} 3! Ai WA ae A, eel & \ \ \\ “ “ . cS forest ie moorland | | 1 Bo | >interatid arid vail ] puria—grassland ‘ tA Wily” 4 Nothofagis-} ® o-grassland . Sets een eys We at cejaforest = oa Zz Wy AY AK CR ae ey “iy a S forest grassland NY KO scrub tagonian- *"monte” Fie. 4. General vegetation of the Andes showing the major vegetation types. 32 BERYL SIMPSON VUILLEUMIER continent and on Tierra del Fuego and surrounding islands (cf., Skottsberg, 1916; Godley, 1960), where two species are present. The specific habitats of individual species are discussed in Part II under each species, and are summarized in Table 2. Physiological Adaptations. Since most (71 per cent) of the species occur in areas with a dry climate (Table 2) and/or high altitudes (with frequent frosts), they have many adaptations to xerophytic conditions. Some of these adaptations are reflected in the time of flowering, type of growth and habit, and seed germ- ination. Flowering seems to be under the influence of several external factors such as day length and temperature regime. Moreover, it appears that most, if not all, species of Perezia sect. Perezia do not flower during the first several years of growth. All attempts to stimulate flowering in the greenhouse have failed. In contrast to the South American species, two species of the North American section (P. thurberi and P. microcephala) grown in the greenhouse flowered abundantly the first year they were sown. These two species are perennials, as are the South American species, but they are weedy, fast growing, and occur at low elevations. Troll (1959) and Hedberg (1964) have shown that, for tropical high altitude plants, the most important climatic influence is the extreme range in diurnal temperature. In high tropical mountains the daily temperature difference far exceeds the yearly range. As a consequence, plants growing at high altitudes (over 3000 m) in tropical latitudes are adapted to having the soil (and thus the available water) frozen nightly while during the day air tempera- tures may reach as high as 30° C. Studies have shown (Hadley & Bliss, 1964; Mooney & Billings, 1965) that plants which are adapt- ed to high altitudes suffer from “over respiration” at low altitudes when grown under usual conditions. None of the Perezia plants from the tropical montane areas of South America survived for more than one year in the greenhouse in Cambridge, Massachu- setts, and all of the plants were stunted, producing few leaves during the one year of growth. For species growing in the Southern Andes (south of 30° S), the seasonal changes in temperature (rather than the diurnal changes) and day length are probably the primary influences in initiating growth and flowering. In contrast, all of the species brought from the southern part of South America (except Perezia lactucoides THE SYSTEMATICS AND EVOLUTION OF PEREZIA 33 subsp. palustris, a swamp plant) survived three years in the green- house at Cambridge, although none flowered. It is possible that these plants from temperate areas could have been induced to flower under carefully controlled conditions, ie., in a growth chamber. Since such facilities were not available, and because it would have been a study in itself, this was not attempted. Seed germination also appears to be different in high and low altitude species. The causes of seed dormancy (or complete fail- ure of germination) of alpine plants are apparently very diverse and little understood (Bliss, 1956; Amen, 1966). Amen (1966), working at sea level with a sample of alpine species, found that over half of his species had less than 50 per cent seed germination. Stratification did not help to increase germination in his samples. However, because of the limited scope of Amen’s study, his results cannot necessarily be extended to the majority of high altitude species. Germination rates proved to be higher when the achenes of Perezia were sown on loose soil rather than filter paper, but in both instances they were extremely low. Achenes of 16 species of Perezia were sown on loose soil in small pots; of these, seeds of only eight species germinated. Germination in the eight success- ful lots varied from 1-10 per cent of the total number of achenes sown, except in the case of P. multiflora in which 50 per cent of the seeds germinated. Stratification to induce more germination was attempted, but without success. The behavior of Perezia seeds thus confirms to some extent the findings of Amen (1966). Predation. There are two different types of predation on plants of Perezia, one directly or indirectly involving man, and the other an insect. Predation by man is due to the destruction of popula- tions and their habitats by farming and grazing of domestic animals. At Checayani, near Azangaro, Pert, where only a few plants of Perezia could be found, I have seen plants being eaten by sheep. The few specimens collected were confined to soil too poor to support enough vegetation for extensive sheep grazing, or were near the hacienda where animals were not allowed. Boelcke (1957) has documented for Patagonia that grazing can have an effect on the composition of the vegetation of an area. Grazing can also affect the habit of a species as shown by Kemp (1937) for Poa pratensis and T rifolium sp. Selection pres- sure from grazing animals undoubtedly contributes to the ap- 34 BERYL SIMPSON VUILLEUMIER pressed habit of several altiplano species and for the spiny, cushion plant-like habit of the Patagonian steppe. Populations of Perezia have been destroyed by farming all along the Andes. Seed germination and growth of most species of Perezia is so slow that once plants have been plowed under or uprooted, they do not reestablish themselves, recolonize new areas, or “shift” to roadside areas. Specimen data indicate that populations and species are disappearing from vast areas of South America which have come under cultivation. For example, the number of species of Perezia recorded 60 years ago from the areas surrounding Santiago, Chile, far exceeds the number of species which can be found there today. In Peri, the type local- ities (and only known localities) of two taxa (P. coriacea and P. macrocephala placed here in synonymy with P. ciliaris and P. pungens) have been completely destroyed by farming. Only Perezia multiflora, one of the few South American species with a high seed yield and quick seed germination, has become a roadside weed. Perezia multiflora also has a selective advantage over other species of Perezia in that its plants are extremely spiny and therefore not grazed by cattle and sheep. The other predator upon Perezia is actually a parasite. Adult moths of the family Muridae (Lepidoptera, identified by Dr. Ellis McLeod ) oviposit into the immature capitula early in the spring. The larvae hatch in time to feed on the maturing young achenes, pupate late in the summer, over winter in the capitula, and hatch the next spring. The infestation of these larvae is truly amazing— in some populations there is no plant found which does not have one or two larvae in each capitulum. Both herbarium specimens and field observation indicate that all species of Perezia sect. Perezia, except perhaps those of the P. multiflora group, are parasitized by these moths. Under these circumstances, it is surprising that a sufficient number of achenes ever reach maturity to keep the populations constant. The lon- gevity of plants of Perezia is probably a major factor in keeping the species successful. A similar type of infestation also occurs in at least one species of the North American section. All of the capitula of plants of P. nana (sect. Acourtia) received from Dr. Leslie Gottlieb were infested with moth larvae. The species of moths involved in the infestations of either section has not been determined. Several pupae were brought THE SYSTEMATICS AND EVOLUTION OF PEREZIA 35 back from South America, but all attempts to have them complete the molt into the imaginal stage were unsuccess Pollination. Only one pollinator was seen visiting capitula of Perezia. In Bariloche, Rio Negro, Argentina, all species were regularly visited by an unidentified species of large, orange bumble bee (Hymenoptera). Although apparently no nectar is present in florets of species of Perezia, all species sampled have a pleasant, sweet odor probably correlated with bee pollination. In direct contrast to the sweet odor of Perezia, species of the related genus Leucheria Lag. have a musky, unpleasant smell. The most common insects found on species of this genus were flies. PALYNOLOGY Comparative palynology, begun by Wodehouse in the early 1900’s and continued by Erdtman, has been used frequently by systematists to clarify problems of relationships in various plant taxa. In order to ascertain its usefulness in the Nassauviinae and within the genus Perezia, both inter- and intrageneric pollen studies were made. Pollen grains from at least two species of each nassauviinid genus (except the monotypic genera) were acetolized according to the method outlined by Erdtman (1952, 1960), and compared. The results, except for slight differences, were consistent with those of Wodehouse (19292) who made a similar study with non-acetolized pollen. As he found, pollen shape and exine mor- phology is useful in grouping genera within the subtribe. An ex- panded discussion of the palynology of the Nassauviinae and its evolutionary implications will be presented in a later paper con- cerning the relationships of the genera of the subtribe. In addition to acetolysis, pollen of two or more specimens of each species of Perezia sect. Perezia was stained with methylene blue, mounted in glycerine jelly, examined, and measured. This technique, rather than acetolysis, was used for several reasons. First, all previous work done on pollen in the Mutisieae was based on non-acetolized pollen (Wodehouse, 1929a; Carlquist, 1957). In order to make the observations comparable, it was felt that direct mounts should be tried. Second, staining with methylene blue allowed a simultaneous check for probable viability of the 36 BERYL SIMPSON VUILLEUMIER pollen. Finally, direct mounts are far simpler to prepare than acetolized specimens. As a control, the diameter of acetolized grains was measured for several species and the measurements were compared with those from non-acetolized preparations: the differences in size were negligible. The staining of the pollen indicates that there is potentially 100 per cent pollen viability in the different species of Perezia sect. Perezia. All of the pollen grains took up the stain well and showed no deformities in shape. In a few cases, anthers which were too immature were used and the pollen had not fully expanded. The grains from these specimens were not measured and only turgid grains with bulging pores were used in the analysis. Table 4 gives the number of grains of each species measured, the mean pollen grain diameter, the standard deviation of the mean, and the coefficient of variation. One hundred grains were measured for each species when possible. When adequate mate- rial was lacking, fewer grains were used. As shown in Table 4, there appear to be three loose categories of pollen grain sizes. The smallest grains occur in the Perezia multiflora species group. Grains of intermediate size are found in the P. magellanica group, larger grains in the P. pungens, the P. coerulescens and the P. recurvata species groups, and the largest in the P. prenanthoides group. Although there are no statistically significant differences in the pollen grain diameters etween species groups, there is a tendency for the species within a group to have pollen grains of the same relative size. At present, no explanation can be given for the differences in pollen diameter. A comparison of the data of Table 4 with those of Table 5 shows that the size differences do not appear to be correlated with differences in chromosome numbers. However, few chromosome numbers are known in the genus. CYTOLOGY The cytology of the Mutisieae has been little studied to date. Chromosome numbers are known for only about 8 per cent of the species in the tribe (ca. 50 of 630). Within the Mutisieae, a diploid number of 2n=54 has been found in species of such un- related genera as Chuquiraga Juss., Cyclolepis Gillies ex D. Don, Plazia Ruiz & Pay., Mutisia L.f., Trixis R. Br., Proustia Lag., and THE SYSTEMATICS AND EVOLUTION OF PEREZIA 37 TABLE 4, DIAMETERS OF POLLEN GRAINS OF PEREZIA SPECIES Stan Coefficient Number of ea deviation Species of Perezia grains diameter of mean variation P. multiflora 100 28.8 1.7 5.9 P. squarrosa 100 30.1 1.4 4.7 P. kingii 100 24.4 17 7.0 P. prenanthoides 100 41.4 1.9 4.4 P. nutans 100 38.9 2.5 6.4 P. punge 100 38.5 1.6 44 P. sublyrata 100 39.8 18 4.6 P. mandonii 50 39.4 es 4.2 P. ciliosa 100 35.7 1.8 5.1 P. purpurata 300 42.5 2.5 6.0 P. pilifera 100 35.2 2.1 5.9 P. carthamoides 100 37.4 2.2 6.1 P. viscosa 110 36.7 1.9 5.2 P. lactucoides 50 35.7 1.4 4.0 P. pedicularidifolia 135 35.0 3.6 10.0 P. lyrata 156 36.9 2.7 7.3 P. fonkii 100 35.8 1.5 4.2 P. delicata 50 38.1 2.7 7.1 magellanica 100 32.3 4.9 14.9 P. calophy 100 36.8 1.2 3.4 P. bellidifolia 110 34.8 2.2 6.3 P. megalantha 100 38.9 1.5 3.8 P. coerulescens 300 42.9 2.0 6.0 P. pinnatifida 50 34.9 2.4 6.9 P. pygmaea 100 37.2 1.6 7.2 ¥. igii 100 39.0 3.0 79 ‘ maar 100 40.5 2.2 5.5 P. recurvata 270 37.3 2.3 6.0 Perezia sect. Acourtia. Diploid counts of 2n=8, 16, 24 (26), 40 and 48 have been reported in Pertya Sch. Bip., Ainsliaea DC., Chaptalia Vent., Leucheria Lag., and Perezia sect. Perezia. The only number in common between these two groups of genera is 2n—26 now recorded from Mutisia, Pertya and (perhaps) Perezia sect. Perezia. The karyology of species of the Mutisieae is even more poorly known than the chromosome numbers. However, a survey of pub- lished chromosome photographs and drawings, shows two things: the karyotypes of species with numbers of 2n=8, 16, 24, 40, 48 38 BERYL SIMPSON VUILLEUMIER . Chromosomes of — species of Ferenia. Fic. 5-1, P. multiflora (2n=16); (2n=24); chr mes. —4, P. thurberii of sect. Acourtia shows a compliment of 2n=54, small, pane ‘cea chromosomes. All photographs are taken from root tip cells stained in basic Feulg THE SYSTEMATICS AND EVOLUTION OF PEREZIA 39 (52) show a mixture of long and short chromosomes (cf., Fig. 5-1 to 5-3) while those species with a complement of 2n=54 seem to have very small chromosomes of more or less equal size (Fig. 5-4). Table 5 lists the chromosome numbers now known in Perezia; five of these counts are reported here for the first time, and two previous counts are confirmed. Figures 5-1 to 5-3 show mitotic chromosomes (from root tips fixed in 8-oxyquinoline and stained in Feulgen) of selected species of Perezia sect. Perezia and Fig. 5-4 contrasts the karyotype of a species of sect. Acourtia. TABLE 5. CHROMOSOME NUMBERS IN PEREZIA TAXON n Qn REFERENCES Perezia sect. Perezia a P. multiflor 16 Diers, 1961; Vuilleumier. Sneider, unpub. P. squarrosa subsp. cubaetensis 4 Coleman, 1968. P. pungens 24 eiser, 1963. iliari. 24 Vuilleumier P. carduncelloides 12 Sneider, unpub P. ciliosa 24 Vuilleumier P. calophylla 24 Vuilleumier. P. coerulescens 24 Diers, 1961; Vuilleumier. P. recurvata 24 or (26) Vuilleumier. Perezia sect. Acourtia P. microcephala A. Gray 54 Raven, in litt. P. thuberii A. Gray 54 Vuilleumier. The chromosome number and karotype for at least one species of every group of Perezia sect. Perezia (except the P. prenan- thoides group) is now known. The counts indicate that four is the basal number in the South American section because gains in chromosome number (by polyploidy or aneuploidy) are much more common in the Angiosperms than decreases (Stebbins, 1950), especially when the equivalent of an entire complement is involved and intermediate stages are not found. In other words, it is much more probable that n=4 (now known in P. squarrosa subsp. cubaetensis ) was ancestral, and that n=8, and n=12 (13) were derived rather than the reverse. However, more counts are necessary to completely clarify the picture. At this time it is particularly difficult to relate the numbers 40 BERYL SIMPSON VUILLEUMIER and karyology of the two sections of Perezia, but future counts of the species of this and related genera should add to our under- standing of evolution in the Mutisieae. CHEMOTAXONOMY Chemical taxonomy is a comparatively recent method employed by plant systematists that clarifies problems of relationship (Mc- Clure and Alston, 1966) and hybridization (Alston and Turner, 1963 a,b). The majority of chemical taxonomic studies have been made using a class of compounds known as the flavonoids, but systematic work has also been done using other groups of chemicals—most recently, enzymes. Comparative enzymology, as stated by Alston (1967), may be one of the most elucidating ap- proaches of any chemotaxonomical work. Enzymes were not used in early studies because, until the last few years, it was more dif_- cult to work with them than with other classes of chemicals. Because of the relative ease of dealing with flavonoids and their previous widespread use in the taxonomy of several plant families, I decided to make a preliminary survey of the flavonoid chemistry in Perezia sect. Perezia. This study was not intended as a detailed analysis, but merely an exploration of distribution patterns of flavonoids in the section to see whether more extensive chroma- tography was indicated. This initial survey was made for two purposes: possibly to solve existing taxonomic problems in the genus Perezia; and, to explore chemotaxonomy and its application in the systematics of the Nassauviinae. Methods. The extraction and two dimensional descending chromatography techniques of Alston and Turner (1963) were used with butanol:acetic acid:distilled water (3:1:1 v/v) as the first solvent, for 24 hours; and acetic acid:distilled water (15:85 v/v) as the second solvent, for 4-6 hours. The chromatographs were inspected under daylight, longwave ultraviolet light, and under both conditions with ammonia vapor. Voucher specimens have been deposited in the Gray Herbarium. Discussion. Before discussing the results obtained from the chromatography of Perezia leaf extracts, it must be pointed out that only a few individuals of a few representative species were analyzed chromatographically (in some cases only one individ- ual). Several individuals from numerous populations of each THE SYSTEMATICS AND EVOLUTION OF PEREZIA » } « @ reuincua i. , @ cHimsorazo~ my! oR ie Sashes SAT R 5 AMAZONAS Poe ie CAJAMARCA. } x HUARON ~~~" } rg ASAPALCA ie se ; cuzco a r A PAZ ee * COCHABAMBA ~~ 12 : .@ (ore SEES, s foes P di POTOSI =f ie . | » JUNUY, tee Sy nen ae ae = ge : } ATACAMAS i | ocr gg FRR a ae SIERRA DE CALCHAQUIES 7 ok ~, yA =e RIOJA - % a =~ Z VALPARAISO} @ puenTe DEL INCA ~~ y TIAGO | MENDOSA SN@- MONTEVIDEO feu ey e. 5 uaenaay 7 sa a perce PILCANIY @ SARMIENTO LAGO BUENOS AIRES@—- ; dig geenane SA LAGO anoenTino nf SANTA INUSOIDAL PROJECTION 6. Localities o BUENTA ARENAS ee) A i ee ae specimens of Perezia used in paper chromatography analysis. on Names with dots are actual localities, names without dots are provinces or departments 42, BERYL SIMPSON VUILLEUMIER species should be chromatographed, and all species should be sampled for a truly accurate comparison. It should also be em- phasized that none of the spots were eluted and purified to give chemicals that could be identified. In some cases the groups of flavonoids could be determined for certain spots, in others they could not. In general, only the spot patterns and characteristic reactions of the spots were used, and as such were considered as a morphological character. Figures 7 to 13 give the patterns of selected chromatograms and Table 6 gives the different spot color reactions. Unless it was quite certain that the spots in different chromatograms repre- sented the same chemical they were assigned different numbers. When the same number is used for a spot in more than one chromatogram, the compound at that spot is presumed to be the same in both cases. Figure 6 gives the localities of the specimens used in the chromatographic analysis. A superficial glance at the chromatograms reveals considerable variation in the spot patterns within a species—even those which are constant in gross morphology. (Cf., Fig. 7-1 with 7-4; 7-2 with 7-3; 12-3 with 12-4; and 10-3 with 10-4.) There is, how- ever, a greater amount of variation in the chromatographic pat- terns of the species that are more variable in gross morphology than in those that are less variable (see Parr II, Taxonomy, for discussions of morphological variation). A pertinent example of this contrast is between Perezia purpurata, composed of several isolated series of populations, each morphologically distinctive (Fig. 23), and P. multiflora, a wide ranging species with relatively little morphological variation (Fig. 8-1 and 8-4 compared with 10-3 and 10-4). Similarly, in a species such as Perezia recurvata with several polymorphic phenotypes, there is considerable intrapopulation variation in chromatography patterns (Fig. 11-1 to 11-4). Also, the spot patterns are more similar between species of the same species group than between those of different groups. In other words, a taxonomy erected on the basis of only the chromato- grams would lead to a grouping of taxa that agrees roughly with that based on morphology (within the limits of the material tested ). A few spots appeared consistently throughout the tests. Two spots, 1 and 2, were useful as indicators on the different chroma- THE SYSTEMATICS AND EVOLUTION OF PEREZIA | 2 Os 0) @® ®) @ 9 6 9 0 @ o? P NUTANS P PRENANTHOIDES LONQUIMAY, CHILE LONQUIMAY, CHILE 3 6 4 cee 9 @) 0) ) g 6) (+) P PRENANTHOIDES P NUTANS TERMAS DE CHILLAN CHILE BARILOCHE, ARGENTINA Fic. 7. Chromatograms of Perezia nutans and P. prenanthoides, the only two members of the P. prenanthoides species group. 44 BERYL SIMPSON VUILLEUMIER ] 2 O ) ee Guiakt Dz On Oo @O [<> = Co i oe. P. CILIARIS P PUNGENS POTOSI, BOLIVIA MT. PICHINCHA, ECUADOR @) D9 ore, Q Co) @ (») a ee BARILOCHE, ARGENTINA JUJUY, ARGENTINA 13. Chromatograms of Perezia pungens, its nearest relative, P. ciliaris, and another species of the P. pungens group, P. ciliosa. A chromatogram of P. pilifera, a very unique species in the genus, is added for comparison. 50 BERYL SIMPSON VUILLEUMIER tograms. Their pink fluorescence in ultraviolet light and their relative positions made them readily identifiable. One or both of these spots were present in most specimens examined, except those of Perezia multiflora, P. nutans, and P. prenanthoides. Three other spots, designated as 4, 5, 6 were also present in most of the chromatograms. Each of these initial observations appears to be consistent with the findings of chromatographic studies of other plant taxa. Intra- specific and intrapopulation variation of flavonoid compounds has been little studied, but it has recently received more attention from those working in chemotaxonomy. Brehm (1966) reviewed the literature on variation of plant compounds and came to the conclusion that future research would show that the same type of variation is present in the secondary chemicals of a plant species as in any morphological character. Brehm (1966) also cited the work of Horn (unpublished Ph.D. thesis, University of Texas) whose research showed that a large amount of intrapopulation variation was present in Baptisia nuttalliana (Leguminosae). Some flavonoids were always present and others were, he felt, randomly distributed in the population. Alston (1967), however, postulated that the more variable compounds which Horn found were not randomly distributed, but rather followed microclinal geographical gradients of some kind. Flavonoid compounds would, according to Alston, presum- ably be under the same influences as other phenotypic characters —different selection pressures in geographically separated parts of the range. Alston illustrated (1967) the chromatograms of two geographically separated populations of Baptisia leucantha and four populations of Hymenoxys scaposa (Compositae). The variation present in these chromatograms is as great as, or greater than, any interpopulation variation of flavonoids I found in Perezia. Problems Attacked in Perezia. Because material available for analysis was limited, attention was focused on problems which could be profitably attacked by chromatography. But first chromatographs were run on different specimens of several species to see whether there were distinct patterns present in different species of Perezia, and to determine whether these patterns ap- peared to be species specific. Preliminary chromatograms indi- cated that there were more similarities in the patterns of THE SYSTEMATICS AND EVOLUTION OF PEREZIA 51 flavonoid and phenolic spots within a species than between differ- ent species. (See, for example, Fig. 7-2 and 7-3; 12-3 and 12-4; 10-3 and 10-4.) Therefore, it was assumed that chromatography would indicate affinities between species. With this as a working hypothesis, the following specific questions were investigated: tions as similar to each other as those of separate populations of other species, confirming or countervailing the decision to place them in one large variable species? - Would chromatographic data be of use in solving the taxonomy of the Perezia coerulescens complex? On the basis of chemical analysis, to what species group would the P. coerulescens complex appear to be related? 4. Would chromatographic evidence indicate that all forms of Perezia recurvata were merely phenotypes of one species or sibling species? To what other species and species group would P. recurvata and its ally P. poeppigii appear to be related? RESULTS . The two species, Perezia prenanthoides and P. nutans, showed very similar chromatographic patterns (Fig. 7-1 to 7-4) with the spot patterns and reactions strikingly paralleling the strong morphological similarity be- tween the two species. The chromatograms of the two species were so alike might show species specific differences. Superficially, the spot patterns of the two species of the Perezia prenan- thoides group were like those of P. multiflora (compare Fig. 7-1 to 7-4 with 10-3 and 10-4). However, it must be noted that although there was a resemblance in the simplicity of their spot patterns, the actual positions of the spots (R, values), and the color reactions were i different in the two cases. Morphologically, species of the P. prenanthoides m e th spot position and characteristics on the chromatograms from specimens bo collected in different populations ( Fig. 8), indicates a close affinity of the pattern of cimens of P, purpurata from om Rioja, Argentina. Of all of the major populations of this species, these two are the most similar morphologically (Fig. 8-1 and 8-2). 52 BERYL SIMPSON VUILLEUMIER similar (Fig. 9-1 to 10-2), there is an almost hopeless diversity present (perhaps also indicating that the treatment suggested here is not the most natural one possible). this c ared wit and 8-4 vs. 12-3 an ‘ e analysis of the chromatography of Perezia recurvata, another con- fusing species, was almost the antithesis of that oerulescens com- tation presented here (Parr II), na , th e spe with areas secondary contact between formerly isolated populations, is inv Although the Perezia recurvata a er. 6 scens species groups are, ern remnants of the plexus from which several major lineages diverged. One line apparently led through P. poeppigii to P. recurvata, and another to the still actively speciating P. coerulescens complex. Unfortunately, not enough material was available to study the species of the Perezia magellanica assemblage or many members of the P. pungens alliance. One specimen of P. pungens and its closest relative, P. ciliaris, were run (Fig. 13-1 and 13-2) to give at least a partial comparison with the other species sampled. e specimen of Perezia pilifera (Fig. 13-3) was chromatographed to see whether the flavonoid patterns of this unique species would give any clues to its affinities. Morphologically and anatomically P. pilifera is very divergent from the other members of the section. The chromatography THE SYSTEMATICS AND EVOLUTION OF PEREZIA 53 pattern proved to be just as distinct as the morphology. The kinds of spot reactions and a part of spot pattern are more similar to those of P. purpurata and P. pungens than any other species examined, suggesting an affinity with these two species. Conclusions. Although no specific problems encountered in a taxonomic study of Perezia sect. Perezia were solved, a chemo- taxonomical survey of several of its members did provide some useful information. The following are among the conclusions arrived at: 1. An array of flavonoids and phenols is present in the basal leaves of flowering specimens of Perezia sect. Perezia and the kinds and the presence or absence of these compounds vary in different individuals, populations, and species of the section. 2. Despite the variation present, the hypothesis of Brehm (1966) that “even in sexually outcrossing individuals, similarity of pat- terns (chromatography) should reflect relationships” appears to hold true in Perezia. It seems that there is the most similarity in chromatographic patterns between individuals of the same species, less between species of the same species group, and the least between relatively unrelated species. 3. Within the South American species of Perezia, chromato- graphic analysis of flavonoids and phenols indicated that Perezia purpurata and P. recurvata, although morphologically variable were internally uniform in their secondary chemical compounds. In contrast, the P. coerulescens complex displayed an array of dissimilar patterns as varied as the morphology of the different populations involved in the assemblage. Several species of the Perezia pungens species group showed chromatographic patterns similar to members of different species groups. This strengthens a hypothesis, based on morphology, that P. pungens and its allies occupy a central position in the section. One evolutionary line from this central complex includes P. pur- purata and the P. coerulescens group. Another appears to lead from P. carthamoides to P. poeppigii, P. linearis and P. recurvata. On the basis of flavonoid chemistry, Perezia pilifera appears iso- lated within the section but shows some similarities to the P. purpurata-P. coerulescens lineage. The Perezia prenanthoides species and the P. multiflora species groups are both tightly knit assemblages, each of which is an isolated unit in section Perezia. 4. There is an indication that future chromatographic analysis 54 BERYL SIMPSON VUILLEUMIER TABLE 6, COLOR REACTIONS OF SPOTS ON PEREZIA CHROMATOGRAPHS! Spot Long UV+ Daylight Spot Long UV+ = Daylight number wave NH, + NH, number wave NH, ' NH, UV vapor vapor UV vapor vapor 1 Br, Pk O-P = 45 Bl - = 2 Pk = = 46 P _ y 3 FE eg y AT - Pk - 4 Bl ~ _ 48 = Pk ~ 5 P _ _ 49 - x 6 Bl - - 50 Wh - ~- « ie y BG 51 = > 4 - 8 P Br Y 52, Bl - 9 ~ - Y 5d P - ~ 10 rE 4 Y 54 Bl ¥ b's 11 P - _ 55 Wh - _ 12 P ~ ~ 56 - xy - 13 Bl x ¥ 3 ff = Wh - 14 ~ - Y 58 Bl bg ¥. 15 - &'é ¥ 59 P Br x 16 - Pk ag 60 Fr - - 17 Bl - = 61 Pr = = 18 Bl = 62 Wh ~- - 19 Bl 7 63 ~ Br 4 20 P - - 64 ~ Br bd PAL Wh -_ 65 Bl ~ - 22 Bl - 66 Bl a4 ¥ 23 Bl ~ 67 ~ Br y 24 P ¥ 4 68 Br Y 25 Bl - 69 Bl = ai 26 Br Y = 70 ~ Br Y 27 Bl Y se 71 * Y is 28 Bl Bd ¥ 72 _ Bl = 29 - _ a8 13 Bl x ¥ 30 ig Bf i é 74 Pk - 31 Bl af i to _ Pk - 32 | og ~ - 76 Bl a ¥ 33 = - y 77 Pk - 34 Bl ~ ~ 78 - Br y Bl - 79 Br _ _ 36 - _- 7 80 P P 2a 37 Bl - - 81 Bl ~ - 38 Wh _ 82 Bl Bl y 39 Pe - ~ 83 BI ¥ Y 40 P - - 84 BI 7 41 re _ 85 Bl Wh - 42 - Bl Y 86 Bl _ Y 43 P - - 87 Bl Wh-Pk 44 r ed ¥ 88 Bl - 1 The chromatograms from which these spots were taken are presented in Fig. 7 to 13. The following symbols are used to indicate wes ferange a colors: Pk=pink Bl= blue Wh=white Br= brown P=purple Y= yellow O=orange THE SYSTEMATICS AND EVOLUTION OF PEREZIA 55 TABLE 6. (cont'd) a ed hay les UV vapor vapor UV vapor vapor 89 Bl - _ 111 Bl ~ ~ 90 iP | - 112 = Br-Y Br-Y 91 Bl - - 113 Pk - - 92 Bl ~ 114 - Br Y 93 Bl - bs 115 - = 94 Pk _ - 116 Bl - - 95 Bl - 1i7 ¥ 1g 96 Bl Bl - 118 Pk - 7 97 Bl 6 1. 119 Pk bg - 98 P Pr - 120 ~ Br 4s 99 Bl - - 121 Bl Bl - 100 Ve ba Y 122 Bl Pk Pk 101 Pk ¥ ¥ 123 Bl - - 102 Bl - - 124 Bl Sg Lg 103 Bl Bl - 125 Bl - - 104 Bl bg vr 126 Bl - - 105 Pk a ¥ 127 Bl Pk Pk 106 Pk - - 128 Bl - sa 107 _ Pk-O + 130=6 Bl - - 108 Bl ~~ ¥ 131 Bl 7 - 109 Br ¥ 132 Bl a 7 110 Bl ¥ ¥ would be useful in clarifying problems found in confusing species complexes, and in hybrid situations. Further study should also show whether changes or variations in flavonoid compounds in different individuals follow geographical clines (as suggested by Alston, 1967) or whether there are random fluctuations in certain chemicals (Horn in Brehm, 1966). NUMERICAL TAXONOMY Numerical taxonomy is a method, used in systematics, which has received considerable attention in the last ten years. How- ever, it should be noted that numerical taxonomy, unlike classical or chemotaxonomy, does not add new characters which the tax- onomist can use; it merely realigns and gives back numerical data which have been gathered by other means. Moreover, as numer- ical taxonomy exists today, it actually restricts the kinds of infor- mation that can be used. As seen below, no satisfactory method for quantification of non-numerical characters has been found. Until this obstacle is overcome, numerical taxonomy will neces- 56 BERYL SIMPSON VUILLEUMIER sarily be biased in its scope, and will lose many characters which are considered important by most taxonomists. Since numerical morphological characters of Perezia specimens were recorded on IBM cards for use in the taxonomic treatment (Parr IT), cards were available for a numerical taxonomic study. It was undertaken with two purposes in mind: as a possible way of presenting data about Perezia species in a new and perhaps slightly provocative manner; and, as a trial to learn and test the methodology and principles of numerical taxonomy. The statistic chosen for use in this numerical taxonomy program was Mahalanobis’ generalized distance D?, in which De= 2, 2, (cov )y (XR) RAs) where p is equal to the number of characters and (cov),; repre- sents the inverted covariance matrix, coy,,, and X, and X/’ are the means for the primary groups X and X’ for character i i. This procedure was used for several reasons. First, a computer program was readily available (written and discussed by Minkoff, 1965). Second, this statistical method, recommended by Rao (1952) and Minkoff (1965), treats only continuous numerical characters, deals only with populations, and takes both variance and covariance into account. The distance D? is actually measured in units of variance between the primary groups with which it is dealing. To determine how the various species (and in some cases con- fusing populations ) would be grouped, on the basis of numerical characters alone, a series of computer programs was run using Mahalanobis’ distance to measure the “taxonomic distance” be- tween primary groups. The term primary group here refers to a group of specimens treated as a unit in a given run of the program. The primary groups were species, subspecies, or local populations of a single species, e.g., any distinct group of specimens whose placement by the computer would provide interesting informa- tion. The fact that “populations” are necessary in the computa- tion of Mahalanobis’ distance precluded the possibility of using individual specimens as the “operational taxonomic unit” (OTU), THE SYSTEMATICS AND EVOLUTION OF PEREZIA 57 as in the method of Sokal and Sneath (1963, p. 290). It is felt by most biologists that populations, and not individuals, should be stressed in systematics (Mayr, 1963; Stebbins, 1950). Two options allowed by Minkoff in his program were used with each set of primary groups. Total covariance method used the total variance-covariance matrix in the calculation of D?. This matrix was compiled by using the average variance of a character over all the primary groups being considered, i.e., in the compu- tation of the covariance from the formula tS (X,-X,)(%)-X,) The values of X, and X, were the means for that character using all of the primary groups. In the second option, the value of each character for each of the primary groups was subtracted from the mean of that character (again X,; and X,) for only its own popula- tion and not the overall mean. Thus, the values of X, and X;, change in the second option, depending on what primary group is being considered. The use of the total covariance method al- ways gives higher values of cov,; than the second option called the intra-group method. Although it is thought to be more meaningful biologically (William Bossert, pers. comm.) to use the intra-group covariance matrix, little difference in the array of D? actually resulted from the two methods. In other words, although the absolute values (numerical values) of D? were different in the arrays using the two methods, the relative relationships of the populations remained more or less the same in the two methods. Some differ- ences were of course produced. Part of the lack of greater differ- ences in the D? arrays, using the two options, could have been due to the fairly consistent primary group size. Rao (1952, p. 364) gave a correction of D2 for bias in the computation due to large differences in the primary group sizes. However, he stated that if ( ny - (where n = primary group size) is very nearly the 1M, n same for all primary groups, the correction is trivial. The differ- ences in the primary group sizes in the runs discussed were no greater than those used by Rao (1952), p. 358) in his example, which he considered to be negligible. BERYL SIMPSON VUILLEUMIER 58 (NPAZESEF J 10 WAL) NIWA ¢ 190M (S/IAIV7U AIWYAOZ) HSOVIHNGS CHL TYDIW SISWILIVIND wsgns) YSOMAXHNRS SVELON (GMLNADIY LALNL WYITOA) 1INOOVEW S3d/IO779F NI GYD é VITOAIHINOS ASONS WAO7TT/L7NW (Svo/L¥ 7Aded GaslW) SVIDVAd gQlalLy wait On vI7TIDUW SIYLSNTH A ASWOS SFAODALIVT Ff ysoaewnds dsens YSo¥aAHNds o/ S200WHHLIYD of beO7TI/LINY YSOAS YeOTI/LIAW a (aad YouuwHLyo y/739MS ‘d VIWa0F) SVIDWAd Y7I7TANSOTE? HAMOS / f y f sTanrnLuyVv3aad a y f y j / (FUHI'Y21NWI7IA O9V7) WITODIOISUTAN TF WSOODSIA oo ‘P2MFnH CCH EITOZIAIAIYIOZIC Fo 04491730 ¢ 2 = 3 is tc “ @ 9 @ e g S8e wy ae 3 wy w 3 *, 2h (SHO/LY 70d0d Wb/NI709) HINCOWEW <¢ SRIVITHD & (S FINS HAITVD FO VAITIS) HLOSAdAI AA 3 (SOW/Lv7need UW/LNIDIY YLO/I WI) HLbANdYNd ¢ (SOOLLY TAd0e FIIHIYWHOULY) YLEdAd aNd ; UNIP/NYT U/EIPTAS-XF COLO wAIDNS (SMOALY Thded // INU DIIVIM Y YIWIC,) SVIW HY O10U9Ad a (SWO/LYTOdCd DWILVIPAG? SUTOSTTINYIOI” (P/ATOZHSHWOd A4IWICAD SWFIISIMNAIOI d (SWI2SI7 NUIO ‘de , WIAdL, 7 SVIISIMIIOI A (SITPAIN d wIWIPI) SNIDSIMNAIWIA be F4/ Tif of N910dF0d A (A vOTOHAPOW SS FPISL) WLWAINIIIY (APOTOMAYPW ,YLUNYI2IA WLYAFOIIA (6 9970 GROG) g/IADFE,) YLOAINZIY A SISO INIT (9a 0716? yaad Le/O9Y %Iwacd] YSO/ TIO a Yso/ 7/2 d C 9AM 'WSPONTY 'vaWINOd A “HWI0S) WLVAINIIY J Y/70F/0/ 7799 J “Le ad7 of U/TON:T/IH7IHOF es cccctctslalinligiiastat zia species based on Mahalanobis’ distance (D2) using o o TOTAL COVARIANCE — (BONVINWA) ,,.,, NI SLINA Fic. 14. Dendrogram of Pere. the total covariance option (see text). The primary group on the far right appears very removed from the other groups partly because it consisted of only one specimen (i.e., 0 variance). THE SYSTEMATICS AND EVOLUTION OF PEREZIA (9am cos & AO RAL) SUIdMAd ¥ SNULAN SBOIONLNWY Bad 5 A/a ILY N/a of O/PA/HIWCS SSOAS WIOTA LL IAW A COMIN CaO7S/LINN ULPAS ICTS IL IAW | 4} (SWOLLY 1A¢0d OFN/W) SNIDN Ae! GALVE TED IW SISNULIY OND “SPAS WSOvaVNeS | @aiL3%ae Angas MUQTOA) LIN CON EW sivtéaw/7 “9/ddIOd d OVIDING? &AP IVI -KF (2H? W21BYT7IA O9Y2) HITEFIAIEWINIZIOR ° (Ne3d Woaeme LH 1/7300L80 BWC) SWIDNd | S8O/OWHALYYD ¢ WSOISIA ‘c (Sv80d S/THNING HIWICS) SWIBITINAIOD 4 , (O90T0HI HOW WHAPTB.) PLUNMNIIA A (926 ‘vsoansy ‘VnwiWed ds aIWa0d) KbAINIIA 4 3 OLIS/ Te S AAAS (S7/0> WHITWO IT UIANS) HLYAAd Ad ‘A SIVOHUIUT ASYAS SACO2ALIY? A vI4a94d of (Seed UNAID wd SIWIOL) SUIPANA A LN (ad of S/ALSAT¢d 8PAS SFI/IINLIG) q MMOTNEW SISWIT/O & (SdPd 3M/LVI9NHD SWBISIMEZOD ; (Sted INH? YWYOULY) Wb ANdYAd @ ; YIM OTD & (994 dnLal WANSINY BIWICI) HLwandand a (SdOd #/TOF//SY/2 of HIWIOL) SNVIOSIMAIOD of (APOTOHAYO US ,, ULUNANITY) §ULUAYNIIA A WIA (0/7798 df WLOSAT of. ; WLU XATENS d POCCN IZ ‘WHONIHAG LW) SWw2I9IVVAd J CMOLLY TACOS WIHAAL) SNFIISTIAIION INTRA-GROUP COVARIANCE (JONVIYWA) |, .0,, NI S.LINN a species based on Mahalanobis’ distance (D*) using etl Fic. 15, Dendrogram of Pere i the intra-group covariance option (see text). As in Fic. 14, the group on the far right appears very distant from the other groups because it consisted of only one specimen. 60 BERYL SIMPSON VUILLEUMIER That the results from the two divergent methods agreed so well in essential points indicates that the program accomplished the task for which it was written. That is, it gave a measure, based on a series of continuous variables, of the distance between two primary groups (populations ). Of the two, the total covariance option actually conformed slightly better to the scheme of relationship arrived at by mor- phological data. There does not seem to be a satisfactory (logical or statistical) explanation for this. There is a likelihood that the slight differences between the two options were actually due to chance. The computer generated D? matrices for the two options of the main program. Fifty-four primary groups representing species, subspecies, and biological populations were used. In the arrays of D?, each of these groups was listed in order, and next to it a block of numbers composed of the distances (D2) between that group and each of the other 53. Lack of space prevents giv- ing the complete matrices, but the dendrograms (redrawn) for each option are presented in Fig. 14 and 15. Unfortunately, they distort much of the information given in the original matrices because of the manner in which they were constructed, i.e., the first two groups joined were the pair with the shortest distance (compared with all other possible pairs) between them, and then the next closest group to either of the original pair (depending on which distance was numerically smallest) was added next, and so on. Obviously, such a system provides no information about the group which was closest to the other member of the original pair of primary groups, or what the distance of a particular group x was to y. The artifacts due to the mechanical method of draw- ing the dendrograms also exaggerated the difference between the two options (Fig. 14 compared with Fig. 15). However, the dendrograms did reflect the difference present in the original matrices in that the picture of distances drawn from the total covariance matrix (Fig. 14) did conform better to a scheme of relationships based on morphology than did the picture drawn from the intra-covariance matrix (Fig, 15). Smaller programs, the results of which are not given here, were run using populations of one species. In most cases, the sample size of the primary groups was so small that there was not enough variance present in various characters to allow an accurate com- THE SYSTEMATICS AND EVOLUTION OF PEREZIA 61 putation of D’. In many of these small runs, a primary group of only one individual was used even though the program called for primary groups of more than one. Whenever a group of only one specimen was encountered in the program, it was dispropor- tionately far away from the other groups. An example of this distortion can be seen in Fig. 14 and Fig. 15 where the group on the extreme right of both dendrograms (P. pungens, former type of P. fosbergii) appears very removed from the other groups. This group was the only one of the 54 used in the main program with one individual. EVOLUTION OF THE SPECIES GROUPS A synthesis of the data discussed above, obtained from mor- phology, anatomy, palynology, cytology, and chemistry, provides convincing evidence for the presence of six species groups in Perezia which have stemmed from three major evolutionary lines. Although the species can be clustered into six well-defined groups, it is more difficult to ascertain the historical relationships between them, because of the internal evolution undergone since their divergence. Clear-cut evolutionary lines are hard to trace between species also because characters have evolved mosaically (sensu Mayr, 1963) within individual species. However, some character states are obviously highly adapted to specialized conditions and can therefore serve as indicators of the direction of change of those characters. By combining the information from several such characters with that provided by cytology and chemistry, some relationships and evolutionary trends emerge. This combined approach has, in my opinion, provided a firm basis for the taxonomy arrived at here and represented schemati- cally in Fig. 16 and 17. The two figures attempt to give a con- ceptual picture. The first does so diagramatically and the second by illustrating representative species and the relationships be- tween the different species and species groups. Each species group will be briefly characterized below and its postulated origin and subsequent radiation discussed to amplify the scheme presented in the figures. Many of the data concerning paleo- climatological, geological, and botanical changes mentioned here will be elaborated upon more fully in a later paper. By all criteria, one of the most distinctive and well-defined 62 BERYL SIMPSON VUILLEUMIER PR PRENANTHOIDES SPECIES GROUP P pinnotitida FP — a P pygmaea R See oe P pilifera SPECI ieee - FP etait al P carauncelloides P ciliose 2 N PR MULTIFLORA atecies pau SPECIES GROUP 7S ta P multiflora P punge P sublyra Pep sent: FP. clliaris P purpurata P kingli P mandonii Pcarthamoides P ViSCOSa P poeppigii P lactucoides > A Pp sian inal SPECIES ‘riod SPECIES GROUP Peat /ine w P pediculariditolia f ecurs va a P bellidifolia P lyrata megalantha Pcalop oe P deli P paseo Fic . Schematic representation of es relationships between the species and ie ih ie rv Perezia sect. Perezia. (See Fic. 2 for the distribution of the grou P CARTHAMO/IDES P POEPPIGH “ie P RECURVATA P MAGELLANICA MAGELLANICA GROUP RECURVATA GROUP Fic. 17. Pictorial representation of selected species ‘of Perezia sect. iggteaggs showing the type of habit found within each species group (compare with TasLe 2). THE SYSTEMATICS AND EVOLUTION OF PEREZIA 63 species groups centers around Perezia multiflora. All of the species of this assemblage are found exclusively, or have popula- tions, in the Paraguay-southern Brazil-Uruguay basin, although P. multiflora itself has its main center of distribution in the high, dry puna of Perd and Bolivia. The three species which comprise this alliance share the unusual (within this section) characters of silky, copper-colored achenial trichomes, hemispherical involu- cres, and a reduced number of involucral bracts. The eastern subspecies of P. multiflora and P. kingii approach some species of Cleanthes D. Don and Trixis R. Br. (two genera of the same subtribe) in habit because of their highly branched flowering stems and numerous heads in a paniculate arrangement. If the trend of evolution within Perezia sect. Perezia (and even within the subtribe Nassauviinae) has been from an ancestral type like Trixis, as suggested by Small, then the P. multiflora group would presumably be closer in morphology to the ancestral stock than any other extant group in the genus. The presence of a chromosome number of 2n=8 for P. squarrosa subsp. cubaeten- sis and 2n=16 for P. multiflora (compared with 2n=24 [26] for all other species which have been counted) also points to this group as primitive. However, its species have several characters which are obviously advanced, such as compacted head clusters, reduced involucre and head size, taproots rather than rhizoma- tous rootstocks, and spinose foliage. Perezia multiflora itself has become weedy and is the only species in the section which can colonize quickly and efficiently. Therefore, although retaining the lowest chromosome numbers in the genus, including the probable base number of n=4, the Perezia multiflora group does not appear to represent the basal complex in the section, nor does it appear to have given rise to any of the other groups. Rather, it seems to be a closely knit cluster of species which radiated in southeastern Brazil from a very early offshoot of the main ancestral stock. The progenitor of this group underwent speciation by splitting in the Paraguay- Brazil-Uruguay basin and P. multiflora probably migrated west- ward into the Andes at a later time. A second, early, major line seems to have culminated in the two closely related species of the Perezia prenanthoides group, both endemic to the Nothofagus forests of southern South America. Morphologically, these two very similar species form the most 64 BERYL SIMPSON VUILLEUMIER unique group of the section. Plants of both species are large, foliaceous herbs with showy open clusters of numerous magenta heads, broad, soft, basal leaves, and achenes with dense coverings of amber-colored trichomes. (PLATE 1-4). Unfortunately, no chromosome counts are available for either species of this group. Superficially, P. nutans, one member of this group, resembles . nana A. Gray, a member of the North American section Acourtia. Perezia nutans is the only species of the South American section that looks at all like any of its northern hemisphere counterparts. Its large acaulescent habit, loose paniculately arranged heads, and montane forest habitat—all considered primitive characters— indicate that the Perezia prenanthoides, like the P. multiflora group, was an early offshoot from the ancestral stock and has retained many characters of the ancient type. However, the evo- lutionary histories of these two early lineages have apparently been completely different. The ancestor of the P. multiflora group, as outlined above, underwent speciation by splitting in the open woodlands of southern Brazil. In contrast, the P. prenanthoides group seems to be the product of a long, relatively uneventful period of phyletic evolution prior to the Pleistocene, during which it became more and more specialized to life within the Notho- fagus forest. The two present species appear to have been recent- ly separated, probably during the Pleistocene. During the glacial periods, a tongue of ice and enormous amounts of glacial out- wash covered the longitudinal valley at the latitude of the Rio Bio Bio (37°S) and effectively cut the forest belt along the slopes into a northern and a southern component. The two members of the P. prenanthoides group, like many other Chilean forest spe- cies, now show distributional limits at about this latitude. The pre-Pleistocene evolutionary pattern of the Nothofagus forest in- habiting species of Perezia is parallel to that found in some bird and frog genera endemic to the southern beech forests ( Vuil- leumier, 1967, 1968). A number of species with varying degrees of specializations make up the rather heterogeneous Perezia pungens species group. Although some of these species have advanced characters, such as petioled leaves and glabrous achenes, the group as a whole, and P, pungens in particular, possesses all of the characters which appear to be unspecialized in the genus. This plexus of species THE SYSTEMATICS AND EVOLUTION OF PEREZIA 65 seems to be the modern remnant of a generalized assemblage which was at the base of the third major evolutionary line. In addition to its own internal evolution, this group seems to have provided the stocks which gave rise to the three remaining species groups now present in the section. In northern Pert, in the upper reaches of the humid montane forests of Cajamarca and Amazonas, there are populations refer- able to Perezia pungens. These populations, isolated from others of P. pungens, are particularly similar in habit to P. multiflora and P. prenanthoides. Thus, there are members of three exceedingly divergent and widely disjunct species groups which show similar- ities in a primitive type of large, caulescent, polycephalous growth form. In distribution, these three groups, the P. multiflora, the P. prenanthoides, and the P. pungens, are found in south- eastern Brazil, the Nothofagus forests of southwestern Patagonia, and the eastern slopes of the central Andes respectively. These same three disjunct geographical areas show other floristic rela- tionships which suggest an ancient connection (i.e., Araucaria, Podocarpus, Chusquea). It appears likely (Gerth, 1941) that a warm subtropical forest covered most of South America during the early Tertiary (Cretaceous to Oligocene). A differentiation of this uniform forest began to occur in the mid-Tertiary. A new floristic assemblage developed from a combination of the indige- nous southern flora and the Austral-Antarctica flora ( Nothofagus, Araucaria, Podocarpus, Proteaceae, etc.) in the southwest, while in the west, the forest became more open and savanna-like. De- spite this differentiation, it is probable that there was fairly con- tinuous forest (although of changing composition ) from southern Chile north to Pert, and east across northern Argentina until the end of the Miocene or beginning of the Pliocene. In the Pliocene, increased aridity (Groeber, 1936) isolated the forests in southern Patagonia from those in Pert: and southeastern Brazil. It is my suggestion that Perezia arose as a leafy, branched, perennial herb during the early mid-Tertiary in open warm for- ests. As the forests were separated, three main fragments of the ancestral stock were isolated: one in southeastern Brazil, one in southern Patagonia, and one on the montane slopes of the cen- tral, rising, Andes. The South American Perezia could not have arisen in the high Cordilleran puna nor the Patagonian steppe because these dry, cold habitats as they are today did not exist 66 BERYL SIMPSON VUILLEUMIER much before the Pleistocene (Berry, 1919, 1922 a, b, 1937 a; Gerth, 1941; Ahlfeld and Branisa, 1960 ). Not only are these habi- tats recent, but the species of Perezia which occur in them are advanced morphologically and have specializations for xerophytic conditions. In addition to Perezia pungens, there are nine other species in the P. pungens group, many of which have become specialized in various characters accommodating themselves to the different ecological niches in the central Andean puna. Migrations from different segments of this group have led to secondary radiations culminating in the three more recently derived species groups (PLATE 1-1 to 1-3). In the Chile-Argentine Andes, both above and fingering into the Nothofagus forest, the Perezia magellanica group occurs. This assemblage has the largest number of species in the section, and consists of small rosette plants, generally with monocephalous flowering stems, and achenes with long, dense double hairs (PLATE 1-5). Two species of this group (P. viscosa and P. lactu- coides) are somewhat different from the others because of their polycephalous flowering stems and their approach, in gross mor- phology, to P. ciliosa and P. mandonii of the P. pungens group. Because the southern high Andes are young (final uplift at the end of the Pliocene, Briiggen, 1950), and because most of the mountains were completely covered by ice several times during the Pleistocene (Caldenius, 1932; Briiggen, 1950; Polanski, 1965), the present distributional pattern of the species on extra-forest (above timberline ) mountain peaks could not have been formed prior to the Pleistocene. The fact that there are numerous species, all very similar morphologically, most with restricted ranges, and some capable of natural hybridization, also attests to their recent origin and distribution. This type of geographic distribution of endemic and restricted species on mountain peaks suggests a cause parallel to that which has been proposed for the Scandi- navian mountains (Hultén, 1937, 1965; F renzel, 1968). There were probably two distinct kinds of barriers which led to the original separation of populations of the Perezia magellanica group. The most obvious kind of barrier present in the Pleisto- cene during glacial periods was the ice itself. Undoubtedly some small populations survived in refugia within, or along the margins of, the ice sheets. However, a more probable kind of barrier THE SYSTEMATICS AND EVOLUTION OF PEREZIA 67 occurred during the interglacials. At the present time, which is an interglacial, the species adapted to alpine habitats above tree line are separated from one another by stretches of unsuitable habitat on the sides of the mountains and in the valleys. The popu- lations on. peaks are thus effectively isolated by expanses of forest. During glacial periods, the ice spread down the sides of moun- tains and across intermontane valleys. At the border of the ice was a zone of the same type of alpine (or tundra) habitat which had previously existed only on mountain peaks above timberline and below the snow (ice) line. Low altitude species not adapted to such harsh environments were eliminated or migrated north to warmer climates. The ice, therefore, had the effect of lowering the vegetation zones to the point where there was continuous alpine or tundra habitat across intermontane valleys, allowing high altitude species to migrate across these valleys. As the ice ages waned, and the warmer interglacials replaced them, the ice retreated, taking with it its border of alpine habitats. Concomitantly, tree species reinvaded the valleys as the climate warmed. The net effect was that species adapted to cold tundra habitats essentially retreated up mountain peaks and were re- stricted to areas above treeline. A species which was continuous across a valley during a glacial period could easily have left populations isolated on neighboring peaks when the interglacials allowed the re-expansion of the forests. These populations would have the potential for speciation during interglacials when popu- lations were geographically isolated. Since several different glacial advances occurred, there was opportunity for a series of periods of alternating migration and restriction. This rapid succession of expansions followed by isolation could easily have led to the pattern seen today in the Perezia magellanica group of several species, all closely related, and limited in distribution. The most specialized, although probably not the most recently derived South American species group, is the Perezia recurvata group. Within this assemblage there is a nice evolutionary se- quence, discernible from the relatively generalized P. poeppigii to the very highly specialized P. recurvata, i.e., from a loose, broad, flat-leaved habit to a highly compact, basally branched cushion plant with recurved, needle-shaped leaves (PLATE 2-4). The three species of this group share the common characters of a special type of achenial trichome (Fig. 3-2), large, turbinate 68 BERYL SIMPSON VUILLEUMIER capitula, and stiff, lanceolate bracts. The reduction in leaf surface with stomata in P. linearis and P. recurvata, and the recurving of the leaves in P. recurvata show progressive steps in the adapta- tion of these species to the xerophytic conditions of the Pata- gonian plateau. Part of the speciation in this group is probably attributable to isolation during glacial maxima, when populations were forced north or eastward by the encroaching ice or restricted to refugia. Chemical evidence, supported by some morphological similarities, indicates that Perezia recurvata and its allies are most closely related to P. carthamoides, a member of the P. pungens group. The affinities, and probable derivation of the P. recurvata complex from a segment of the P. pungens alliance emphasizes the cen- tral position as an ancestral plexus of the species associated with P. pungens. A group of taxa, the Perezia coerulescens complex, is centered in the altiplano of Pert, Bolivia, and northwestern Argentina. All three of these species have adapted to the bizarre xerophytic con- ditions of high tropical mountains (e.g., see Troll, 1959) as evi- denced by their reduced stature and compact rosettes tightly appressed to the ground with the heads hidden among the leaves (PLATE 2-1 to 2-3). Available information indicates that this group is the most recently differentiated of the section. Morphologically, the species are very similar, leading to taxonomic confusion. In many ways, the group exhibits the characters of a hybrid complex rather than a species group. Yet, although there is evidence of hybridization in some localities, there seem to be distinct non-interbreeding species in other areas. The assemblage is obviously in a period of active speciation with incomplete reproductive isolation having been achieved. Whether the course of evolution will lead to rein- forcement of isolating barriers, or to the submergence of the species will probably be determined in large part by the amount of future disturbance of their habitats by man. Morphological and chemical evidence suggest that the Perezia coerulescens complex is related to P. purpurata of the P. pungens group. The affinities of P. coerulescens and its allies to a species related to P. pungens once more show how the P. pungens group is the focal point of relationships for the three most recently divergent groups. THE SYSTEMATICS AND EVOLUTION OF PEREZIA 69 To summarize, the ancestral type of the section was probably a relatively large, leafy, perennial herb with a rhizomatous root- stock and a loose panicle of heads. The most likely chromosome number was 2n=8, and the karyotype was presumably composed of large, metacentric chromosomes. This early Perezia would have grown in open, cool subtropical (or warm temperate) forests. From this basal stock, three major lineages diverged, beginning in the mid-Tertiary. One of these lines, established in the south- eastern Brazil lowlands, underwent a minor radiation leading to the three species of the Perezia multiflora group. A second line became increasingly adapted to the dense Nothofagus forests in which it underwent a long, relatively uneventful period of phy- letic evolution. A recent separation of populations by a glacial barrier initiated the speciation of the two closely related species now found in the P. prenanthoides group. The third major line, which inhabited the eastern montane slopes, radiated into the habitats which opened up as the Andes were increasingly uplifted. Over a period of time, a plexus of species was formed due to the isolation of populations on differ- ent ranges (or in different valleys) by unsuitable intervening terrain. From segments of this complex, three new lineages di- verged. One colonized southward along the Andes in the late Tertiary, becoming established on several southern peaks. Dur- ing the Pleistocene glaciations, these populations were subjected to alternating periods of expansion and isolation. Migration was permitted during glacials when the ice was low enough to pro- duce a continuous band of alpine habitat from one mountain to another. Restriction of ranges occurred in interglacials as the forest reinvaded the intermontane valleys, making them unsuit- able for alpine species. Local selection pressures on different mountains acting on isolates from three interglacial periods re- sulted in a rapid multiplication of species and produced the numerous, closely related taxa of the Perezia magellanica group. Another segment of the Perezia pungens alliance, adapted to the increasingly xerophytic conditions of the late Tertiary, in- vaded the southeastern Andes and the Patagonian steppe. The three species of the P. recurvata group which resulted from a radiation of this stock still show an evolutionary sequence from a species of the dry Andean valleys to one of the Patagonian steppe. Within P. recurvata itself, isolation of populations in the 70 BERYL SIMPSON VUILLEUMIER Pleistocene by encroaching ice tongues and innumerable streams of glacial outwash led to a pattern of complicated geographical variation when the isolates again came into contact during inter- glacial periods. The third evolutionary line, culminating in the Perezia coeru- lescens group, arose from an ancestral stock derived from the P. pungens group which had become adapted to the conditions of the very high puna. The formation of the three species of the P. coerulescens group must be exceedingly recent because the specialized high tropical habitats in which they occur became available for colonization only at the end of the Pliocene or beginning of the Pleistocene. Differentiation of populations oc- curred later in the Pleistocene when isolation was effected by glacial ice and a complex series of lakes across the altiplano. Whether the isolation was sufficient to allow the development of effective reproductive barriers between the three taxa is still disputable. There does seem to have been enough separation to have permitted at least partial speciation. There is some evidence that interspecific barriers in this group are being broken down because of the disturbances of the altiplano habitats by man. THE SYSTEMATICS AND EVOLUTION OF PEREZIA 71 TAXONOMY PEREZIA Lagasca, Amoen. Nat. 31. 1811. Type species: Perdicium magellanicum L.. Clarionea Lag. ex de Candolle, Ann. Mus. Hist. Nat. Paris 19:65, 1812. Type species: Perdicium magellanicum L.f. An illegitimate name because it was superfluous when published. Clarionea Cassini, Opus. Phytol. 2:165. 1826. non Clarionea Lag. ex DC. Type species: :Perdicium lactucoides Vahl. An ille egitimate name because it was a later homonym of Clarionea Lag. ex DC. Clarionia D. Don, Trans. Linn. Soc. tage I 16:204, 1830. Presumably an orthographic variant of Clarionea Lag. ex DC. mi Clarione nema Philippi, Linnaea 28: 717. 1858. Type species: Clarionema umilis P. Homoianthus DC. Ann. Mus. Hist. Nat. Paris 19:65. 1812. Type species: was neat when publis Homoeanthus Sprengel, Syst. Veg. 3:503. 1826. An orthographic variant for Homoianthus DC. Heteranthus Cassini, Dict. we Nat. 21:110,. 1821. An admitted ortho- graphic change for Homoian Isanthus DC. Prodr. 7:63 ‘1838. ‘An invalid name listed in synonymy with Homoianthus by de Ca ndolle. Dumerilia Lessing, cae 5:13, 1830. non Dumerilia Lag. ex DC. Type ers Drozia Humboldtii Less. An illegitimate name because it was a later homonym of Dumerilia Lag. ex Scolymanthus DC. Prodr. 7:63. 1838. An invalidly Bp ar name listed only by de Candolle in synonymy with Homoianthus st ae maa — Synop. Comp. 412. 1832. Type species: Perezia recurvata (V. This name is frequently listed as a bab of Perezia, but mg was tke used only as a ion Me name by Lessing in Per Drozia Cassini, Opus Phytol. 2:170. 1826. Type species: Drozia dicephala C ia D. _ bray Linn. Soc. Ser. I. 16:203. 1830. Type species: Pogonura DC. ex Seales, Introd. Nat. Sys. ed. 2. 1836. A nomen Scdiek « iS ge to de Candolle by See Sut jean never published i de Can Proustia otis sH Thelecarpaea DC. Prodr. 7:27. 1838. Proustia reticu- ae Lag. e x D. r like to broadly oblong or weate, mucronate, acute or obtuse, entire, dentate, lacerate or ciliate, clasping; usually reticulately veined; coriaceous to char- taceous; glabrous to densely pubescent. Basal leaves in a variable rosette, 72 BERYL SIMPSON VUILLEUMIER linear, lanceolate, lyrate, spathulate, oblong or ovate, acute to obtuse, some- times with recurved margins, usually with a flat blade, margins entire, ciliate, dentate, pectinate, lacerate, or pinnately parted; attenuate at the base o iole; 2 mm to 2 with a distinct pet spicuously ribbed, glabrous, glandular-pubescent or lon e omes. Receptacle flat or slightly convex, glabrous, with scattered glan- dular or long trichomes, or dens fte lon mes aro ag ee Generel ite uc swe sme te section Acourtia. Caudex glabrous; capitula radiate; involucral bracts frequently soft, but sometimes rigid; florets usually blue, sometimes yellow, magenta, pink, violet, crimson, rarely white section Perezia. > PEREZIA SECTION PEREZIA root. Basal caudex glabrous or with a few scattered glandular trichomes. Basal leaves usually attenuate or clasping; in a few species petioled. va coffee, purple, magenta, violet, red, or crimson. Corolla usually glabrous or in a few cases with glandular trichomes on the neck and the under surface of the ligule. KEY TO THE SPECIES A. Plants with leafy flowering stems, more than two capitula per flowering stem, (B). THE SYSTEMATICS AND EVOLUTION OF PEREZIA 73 B. Basal leaves spiny, ciliate, or with small dentate segments; capitula or ina gene inflorescence, not showy; florets blue, white, cream, yellow, rarely Be § by F C. Basal leaves gos (or lacking) and ovaries covered with a very dense covering of copper-colored double hairs ee D. Capitula longer than 10 mm; pappu brow: w Oo Saks Ui ba | eles ag Re eee st aeee tye : 2.2 D. Capitula less than 10 mm long; pappus pure white. 3. b. ki C. Basal leaves petiolate; achenes with a moderate covering of blond trichomes, glabrous, or with scattered trichomes . Basal leaves with large, obtuse, soft, doubly dentate teeth; ‘capitula in a loose inflorescence, showy; florets magenta, i ht o 4. P. hr gear F. Capitula turbinate, nodding ..................----. nutans. G. Basal leaves with undulate margins or blunt teet! (Hl). owering stems decumbent, capitula er Be outer bracts l PLN, Se Acie eee ee ke sublyrata. etre stems upright, capitula us or shortly " turbinate : I. Achenes with dens e glandular hairs or dense double hairs; foliage with fae glandular trichomes, ( J. Achenes with dense glandular Ea Bees es. 6. P. pungens. J. Achenes with dense silky double hairs... ... S a e foliage with only a ri eel tric hom : K. Outer bracts foliaceous; florets yellow r ie eee e. c G. a cath with sh teeth, cae in outline, “a i M. r bracts densely pubescent with — trichomes eben es oe irpuri — N. "Achenes glabrous, with short sparse trichomes, or with glandular trichomes; receptacle viper s or with scattered long trichomes, (O). O. Leaves linear, linear-lanceolate, or sondleshaped due to recurving of the margins, (P se P. Leaves with r saa marge 30. P. recurvata. P: — with flat a a, (Q). ; margins ssictth leaves petioled .... 10. Q. Leaf margins ciliate or wi with long white spines, (R). . Leaf margins densely and evenly ciliate. 29. P. linearis. P. mandonii. BERYL SIMPSON VUILLEUMIER R. Leaf margins with scattered long soft white spines . AAS ie Leste Maes petunia ig Bag Fe pilifera. O. Leaves lanceolate to ovate in outline, dentate, ie. or spiny along the margins, (S). S. Outer bracts pandurate or orbicular in outline, as long as, or longer than, the inner bracts, sometimes thickened at the apex ; reduced; basal leaves deeply incised, segments rounded and conduplicate; capitula oe among the OE SRE LO REN a E, 26. innatifida. . Plants tall, robust, upright, basal leaves rie with flat segments; flower ring stems rising well above the rosette .... = Pe aid ae tt gs a coe es ae ern aie cuit yrata. S. Outer bracts lanceolate to ovate, shorter than the inner : bracts, ey toothed at the apex, (U). asal leaves ped 3-4 deep, rounded segments; plants EE IRN 8 OR tic Seay de ish ai 27. P. pygmaea. U. Basal leaves ma a or with numerous lobes or teeth; plants over 3 cm tall, (V). V. Involucral bracts lanceolate, bright green in the center; flowering stems rising well above the basal rosette .... Nic a eperggee e me enti ye Soe AER « 10. P. mandonii. V. Involucral bracts ovate, dark aig or reddi sh in center; flowering stems the same length as, or slightly longer than, the basal leaves, (W). W. Bracts soft, slightly scarious, entirely aaa r brown Paeusilnk s cauepeiee eats aueeae ferilenens N. Achenes with a dense covering of silky double hairs; eeotie with tufts of trichomes, (X). X. Basal leaves with smooth or undulate margins (often absent in herbarium material of P. lactucoides); involucral bracts lanceo- late, acute, (Y). Y. Basal leaves ONO ne eee Se ces oes Y. Basal leaves asad at the base, (Z Z. Basal leaves ovate, outer oo. ‘broadly sears i 3a eee aN ee ee ere P. bellidifolia. Z. Basal leaves etaipeet e in ~— outer bracts not scarious or with a narrow scarious m 16. P. lactucoides. . Flowering stems robust, se ing m sega three stem leaves; ligules with glandular org Raat .. 15, P. viscosa, ' stems delicate, bearing three od cipal stem leaves; ligules glabrous ................ . delicata. X. Basal ernst die 2 dentate, or deeply lobed (or alice and fleshy ) with long soft white spines, (b). b. Basal leaves and outer bracts with soft, long a spines .... ye Es pen er aad, Lagos ilifera. b. Basal leaves non-spiny, serrate, dentate, phat lobed, or ciliate c. Basal leaves and outer bracts evenly and —. ciliate .. P. ciliosa. c. Basal leaves dentate or lobate, (d). THE SYSTEMATICS AND EVOLUTION OF PEREZIA 75 d. — bracts spathulate, orbicular, or circular in outline times cordate e. “Ou ae bracts acuminate, cordate, — entire plant hispid alantha, Pu eo & io} = oo - pe] QO a = 4 ~ > @ i} = _ ~ | © ® ° ao ee: ra) 5 ° S = 4 ‘ (i). f. Flowering stems robust; outer bracts ‘idk deeply (g). g. Outer bracts deeply pac capitula hemispherical; plants with abundant eee Ne trichomes ........ aun hs gl EE gery P. pedicularidifolia. . Outer bracts entire, very seid oe broadly turbinate; plants with scattered er NE iy stinks Dactbeay SINE peices purpurata. f. Flowering stems delicate, bracts het entire or slightly serrate, (h h. Outer bracts long and narrow, stiff, lanceolate, bright green, prominently scario ; florets cream , yellow, red or blue ............ 28, P. poeppigii. h. Outer bracts ene lanceolate, delicate, reddish in color, slightly scarious; florets white or blue, (i). i iate; 1. Perezia MuLTIFLORA (H. & B.) Less. Tall robust leafy rosette plants 15-74 cm tall with a thick woody taproo Stem round in cross section, striated, covered with multicellular ar ae an which are exceedingly dense under pitulum. Stem leaves n ous, lanceolate, acute or mucronate, usually g; some scattered claspin glandular trichomes on the surface. Basal leaves in a variable rosette, lanceolate, attenuate at the base, xP gil ie mucronate, dentate—sometimes wide, 3.1-37 cm long. Inflores- cence a panicle of heads of 3-46 ae often more a one flowering stem per plant. Capitula campanulate, 11-25 mm wide, 10-22 mm long; right. iin hemispherical; 9-23 mm wide, 7-18 mm long; compos: : 2-4 rows of bracts. Outer bracts ovate, mucronate, spiny toward the base m long; bearing dense multicellular glandular : . ; r gas from 15-35 76 BERYL SIMPSON VUILLEUMIER silky red or blond trichomes. Mature achenes to 4 mm long, dark in color with fewer silky trichomes than the ovaries. Receptacles with dense tufts of long trichomes around the points of achene attachment. KEY TO SUBSPECIES Heads usually 9 or more per peduncle, florets bluish, basal leaves usually long. la. P. multiflora subsp. multiflora. Heads fewer than 9 per flowering stem, but several flowering stems some- times present per rosette, florets white, basal leaves absent or if present usually shorter than 6 cm and with rounded segments .................. lb 1(a). Perezia MuttirLora (H. & B.) Less. subsp. MULTIFLORA Chaetanthera multiflora Humboldt & Bonpland, Pl. Aequin. 2:168. Planche 135. 1809. Type: ecu Perezia multiflora & B.) Lessing, Linnaea 5:19. 1 Homoianthus multiflorus (H. & B Candolle, Prodr. 7:64 ; zia multiflora (H. & B.) Less. var. achalensis O. Kuntze, Rev. Gen. 3(2):167 ARGENTINA. Cordoba: Sierra Achala de Cérdoba al ie de Cerro Gigantes, 8-I-1887, Hieronymus s.n. (NY . (NY, Isotype é Clarionea polycephala Cassini, Opus. Phytol. 2:167. 1826. An illegitimate name because Cassini used it to replace the name Chaetanthera multiflora Perezia bidentata Meyen, Reise um die Erde 1:470. 1834. Type: PERU. Puno: Talaram, 14000-15000 ft, IV—1831, Meyen s.n. (Photo GH of type B Perezia acanthoides Hooker & Arnott, Comp. Bot. Mag. 1:33. 1835. Type: ENTINA. M i een). erezia glomerata Rusby, Mem. Torrey Club 4:214, 1895. Type: BoLIvia. Cochabamba, 10000 ft, 1890 Bang 736 (NY). ts tall, averaging 34 cm in height. Basal leaves usually in a dense rosette; usually over 6 cm long, spiny along the edges. Capitula usually 9 or more per flowering stem, clustered in a tight inflorescence (except in the Cérdoba populations). Ligule 3 mm long, blue or whitish blue in color. romosome number: 2n=16 (Fig. 5-1). Distribution: from southern Colombia south in the Andes through Ecua- dor, Peri, and Bolivia to extreme northern Chile and central Argentina (Fig. 18). Altitudinal range from 1000 m to 4500 m. Flowering from December to July. Representative specimens: coLomp1a. Cauca: Alto Volcan Puracé, 3000 m, 7—XI-1948, Agredo, Molina, Barkley 18Ca082 (US), 3700 m, II-1938, von Sneidern 1958 (GH), 2600-3000 m, Lehman 5670 (F, GH), Cordil- lera Central, Paramo de Puracé, South of Volcan San Francisco, 3450-3500 m, 23-VI-1943, Cuatrecasas 14684 (F). ecuapor. Pichincha: Mt. Pichin- cha, 3800 m, Mille 748 (GH). Cotopaxi: Cordillera Occidental, Cordillera y Zumba > Barclay & Juajiboy 7984 (US). Tungurahua—Napo-Pastaza: Roma Paramo al este de San José de Poalo, 3300 m, 31-VIII-1959, Barclay & Juajiboy THE SYSTEMATICS AND EVOLUTION OF PEREZIA 77 9231 (US). Chimborazo: Volc4n Chimborazo, VI-1964, F. Vuilleumier 1 (GH). Cafiar: near El Tambo, 9500-10000 ft, 5-VII-1945, Camp E4011 re) Ld er . Colorado near Antaicocha, east of Canta, 3800-4100 m, 20-VI-1925, Pennell 14652 (GH); Rio Blanco, 12000 ft, 8-19-V-1922, Macbride & Featherstone 654 (GH). Junin: Chicla 12-13000 ft, 21-V-1882, Ball s.n. GH). Puno: Araranca, 410 00 m, 21-VI-1925, Pennell 13429 (GH); Huancane, Moho, 3125 m, 19—XII-1919, Shepard 109 (GH). Huancavelica: Huancavelica, quebradas west from Huancavelica, 3900 m, 10-ITI-1939, Stork & Horton 10846 (GH); Machacchuay, between Conaica y Tinyacella, 3850-3900 m, 28-III-1952, Tovar 867 (GH); Tansiri, Huaytanayoc, cerca a Manta, 4400-4500 m, 31-III-1953, Tovar 1174 (GH). Arequipa: without locality, 2000-3600 m, 3-II-1912, Guenther & Buchtien 911 (HBG). Tacna: Tacna, Cordillera de Volcdn Tacora, Chislluma, 4500 m, IV-1926, Werder- mann 1142 (GH, US). soxtvia. La Paz: La Paz, Buchtien 4811 ( Tiaguanaco, 3860 m, III, West 6374 (GH); Larecaja, betwee Pongo and Anilaya, 3600-3900 m, IV-1857, Mandon ro— > ache bei Tarija, 3600 m, 30-I-1904, Fiebrig 3018A (GH). ARGENTINA. 0 ft (GH). Salta: Santa Victoria Lizoite, 3340 m, 1-IV-1940, Meyer ¢> Bianchi 33037 (GH); Quachipas, Alemania 1600 m, 18—XII-1929, Venturi 9944 (GH). Tucumén: Anfama, XII-1871, Lorentz 406 (CORD); Sierra de Ciénega, 10-I-1874, Lorentz & Hieronymus 712 (CORD); Sleumer 186 (LIL). Catamarca: Andalgala, 12-IX-1915, Jorgensen 1326 (GH). Cérdoba: Copina, 29-XII-1935, Burkart 7513 (SI); Pampa de 92— i cute. Tarapacd: Arica, Portezuelo de Chapiquina, 4200 m, 29-III-1961, Ricardi, Marticorena & Matthei 334 (CONC). The range of Perezia multiflora far exceeds that of any other species of the section as is clearly shown by a comparison of Fig. 18 with the other distribution maps. Its distribution (including both subspecies) covers a north-south distance of almost 4800 km and an east-west distance of 3200 km. It appears that part of the wide range of P. multiflora is due to the distribution of its achenes by water. Field observations and collection data indicate that plants tend to grow near streams or ditches which are cut BERYL SIMPSON VUILLEUMIER P MULTIFLORA subsp. MULTIFLORA * subsp. SONCHIFOLIA * ap \ si a eter pee” SOM Ne 90 80 60 50 Fic. 18. Distribution of Perezia multiflora. In this, and all the subsequent distribu- tion maps, s May represent one or several collections ee at that locality. If two localities are very close together, they are indicated by only one symbol. THE SYSTEMATICS AND EVOLUTION OF PEREZIA 79 by the run-off waters during the rainy season. Another factor which has been influential in allowing the species to maintain its range is the prickly nature of the plants which discourages brows- ing by sheep and cattle. This habit gives P. multiflora a definite selective advantage over many other species which are killed off by grazing animals. It is possible that there has also been active distribution of the species by man. Bunches of the leaves of Perezia multiflora subsp. multiflora are sold in the markets of the altiplano of Peri and are used as a remedy (in tea) for altitude sickness and general stomach trouble. There is little difficulty in separating Perezia multiflora from the other species of the section because it is so distinctive and, except for some minor variation, exceedingly constant morpho- logically. The small populations in the Pampa de Achala show some morphological differences from the disjunct Andean popu- lations. The Achala populations were considered to be a sub- species of P. multiflora by Kuntze because they have more open branching and fewer capitula. The florets of the Pampa de Achala populations also seem to be much brighter blue than those in the Cordillera. However, when a large series of specimens from the Andes is examined, enough variation is evident to warrant the in- clusion of plants from Achala into P. multiflora subsp. multiflora. Chromosome counts have been made for several populations of Perezia multiflora subsp. multiflora. Two counts were made from the main Cordillera (Ecuador and Pert) and one count from the Pampa de Achala population (Table 5). A haploid number of 8 was found in all cases. 1(b). Perezia MULTIFLORA subsp. SONCHIFOLIA (Baker) Vuilleumier comb. nov. Perezia sonchifolia Baker in Martius, Fl. Brazil, 6(3):380. 1884. Type: el . . Perezia sonchifolia Baker var. tandilensis O. Kuntze, Rev. Gen. 3(2):167. 1898. Type: ee Buenos Aires: Tandil, XI-1892, Kuntze s.n. (US, Iso P). Perezia aletes Macbride, Rhodora 20:151. 1918. Type: UNITED STATES. Massachusetts: North Worcester, 9-IV-1918, Horr s.n. (GH). Plants fairly small averaging 27 cm in height. Basal leaves absent at flowering time or generally shorter than 6 cm. Heads in an open inflorescence 80 BERYL SIMPSON VUILLEUMIER Conien, 24~X-1962, Leal 22300 . Rio Negro: vicinity of General Roca, 250-360 m, IX-II-1914-1915, Fisher 134 (GH, NY, ; ZIL. Santa Catarina: Serro do Oratorio in Araucarienwald, I-1889, Ule s.n. L (G). Sierra de Tolis, XI-1892, no collector (NY). Although Perezia sonchifolia has previously been considered to be distinct from P. multiflora, the trend of morphological varia- tion present from west to east across central South America indi- cates that the P. sonchifolia populations are merely the ends of what was once a more “continuous” distribution of P. multiflora across the continent. These populations are considered here as a subspecies of P. multiflora rather than as a separate species. Going from west to east across the range of P. multiflora subsp. multi- flora, there is a decrease in the size of the plants, the amount of spininess, and the number of heads per flowering stem. Corre- spondingly, there is a slight increase in the size of the individual capitula. The populations of P. multiflora subsp. sonchifolia in southern Uruguay are simply more extreme in all of these charac- ters than the easternmost populations of P. multiflora subsp. multiflora. There is a great difference in the altitude at which the two subspecies grow. Perezia multiflora subsp. multiflora grows at high elevations, subsp. sonchifolia is a lowland subspecies (Fig. 18). There is also one report of P. multiflora subsp. sonchifolia growing in an Araucaria woodland. In conjunction with the difference in altitude at which the two subspecies grow, it is interesting to note that there is a statistically significant negative correlation in Perezia multiflora subsp. multiflora between (1) altitude and the width of the head, and, (2) altitude and the length of the ligule. P. multiflora subsp. sonchifolia is found at lower elevations than any plant of P. THE SYSTEMATICS AND EVOLUTION OF PEREZIA 81 multiflora subsp. multiflora and has broader heads and longer ligules than specimens of P. multiflora subsp. multiflora. The only species to which Perezia multiflora subsp. sonchifolia is similar is P. squarrosa (especially subsp. squarrosa). The two are sympatric, however, in Uruguay, and can be distinguished easily on the basis of the basal leaves and the involucral bracts. The basal leaves of P. squarrosa subsp. squarrosa are present when the plant is flowering and are very spiny along the margins. Plants of P. multiflora subsp. sonchifolia have usually lost their basal leaves by flowering time or have a few curled leaves with rounded segments. The involucral bracts of P. multiflora subsp. sonchifolia are not spiny as they are in P. squarrosa subsp. squar- rosa. 2. PeEREZIA sQUARROSA (Vahl) Less. Robust rosette plants 19-82 cm tall with a deep taproot. F lowering stems i ing 7-20 stem leaves. Stem en few scattered glandular trichomes. Basal leaves usually numerous, linear- lanceolate to broadly lanceolate in outline, mucronate, edges deeply divided into fleshy segments each terminated with a white spine, or shall tate with dentate segments; attenuate at the base, 5-34 mm wide long; surface with scattered glandular trichomes and sometimes with a few very long (to 5 mm) multice ichome: panicle of 4-70 heads. Individual capitula campanulate, 1-2.5 cm wide and 8-10 mm long; upright. Involucre hemispherical, 6-20 mm wide, 7-15 mm long, composed of 3-4 rows of bracts. Outer bracts oblong to ovate, or infrequently lanceolate, mucronate, spiny at the base; m wide, 4-11 mm long, with glandular trichomes on the surface and usually slightly scarious at the base. Inner bracts lanceolate to oblong, mucronate, entire, n pex; scarious at the base and along the — ap setose 1 long, blond or red in color. Florets white, blue, violet, or magenta; outer florets 9-15 mm long with ligules 1- ong; frequently with achenes 2-3 mm long, covered with long silky double hairs over glandular trichomes. Mature achenes to 5 mm long, dark brown, with double hairs much more widely spaced than on the ovaries. Receptacles with tufts of silky tri chomes. Distribution: southeastern Paraguay; Brazil in the provinces from Rio de Janeiro south; Uruguay along southern border to the Atlantic Ocean (Fig. 22-1). Flowering from October to January. KEY TO THE SUBSPECIES Basal leaves with dense even white spines along the margin, heads broadly campanulate 2a. P. squarrosa subsp. squarrosa. §2 BERYL SIMPSON VUILLEUMIER Basal leaves with even teeth without spines, heads narrowly pa 2b. P. squarrosa subsp. cubaet 2(a). PEREzia sguarrosa (Vahl) Less. subsp. SQUARROSA Perdicium squarrosum Vahl, Skriv. ae Selsk. Kigb. 1:11. Tab. 6, 1790. Type: urnucuay. Canelones: sommet du Morne de Montevideo, 1767, Com- merson s.n. (C, Isotype P). Perezia squarrosa (Vahl) ee Linnaea 5:15. Homoianthus squarrosus (Vahl) de Candolle, ane 8. Homoianthus ambiguus Cassini, Opus. Phytol. 2:167. 1826. Pes pen name because it was saben when published. Cassini cited Perdicium spuarrosum istribution: southern Pokey atl Uruguay along the Uruguay River and the Atlantic coast (Fig. 2 sail Sica owering from November to December. Representative specimens: AGUAY. Paraguari: Ybytimi, 9—-X-1952, Montes 12951 (LP). rears "Ware 90-1X— 1952, Montes 12919 (LP). uRUGUAY. Canelones: sommet du Morne de Montevideo, IX-—1767, Com- merson 93 (P), XI-1864, Fruchard 55 (P). Maldonado: Cerro de las — Chebataroff 3006 (LP); Cerro Blanco, oeste del Cerro de las mas, 400 m, Chebataroff 3008 (LP); east bank of Rio Uruguay, 1816, Catal 2082 (LP >), 2(b). Perezia sguarrosa (Vahl) Less. subsp. CUBAETENSIS ess.) Vuilleumier Comb. nov. Perezia cubaetensis Lessing, Linnaea 5:16. 1830. Type: sraziL. Santa Catarina: Cerro de Cubatao, Sello 3840 (Type destroyed at Berlin, Isotype Fr): Homoianthus cubaetensis (Less.) de eee Prodr, 7:64. 1838. Perezia la aevis Less. Linnaea 5:18. Tab. 1, Fi ig. 22 f&g. 1830. Type: B ve heads a large panicle. Individual piace naiowly campanul ate. Outer bracts lanceolate, acute. Florets blue, violet or reddish in color romosome number: 2n= Distribution: scutheanees Brazil. F lowering from October to January Fig. 22-1 Representative specimens: BRAzIL. Rio de Janeiro: Itatiaia, Campo do Sil- verio, 23—I-1873, Clarion GS80 (P). Sao Paulo: Capital, 18-X-1893, Edwall 17004 (NY); Butantair, 12-X-1917 Hoehne 681 (US); Rua ving solacao, Hoehne (US). Santa Catarina: Matos Costa, 1200 m, 9—XII-1 Klein 3584 (LP), 1200 m, 27-X-1962, Reitz ra Ry 13717 (LP); Serra “ Boa Vista, Sao Jose, 1000 m, 13-X-1960, Reitz & Klein 10164 (LP); Campo Alegre, 1000 m, 17-X-1957, Reitz & Klein 5158 (US), campo and pinheiral, 4 km S. of Campo Alegre on the road to Jaragua do Sur, 900-1000 m, 6—-XI-1956, Smith #3 Klein 7323 (NY, US); Serro do Oratorio, Bom THE SYSTEMATICS AND EVOLUTION OF PEREZIA 83 Jardim, Sao Joaquim, 1400 m, 23-X-1958, Reitz & Klein 7462 (LP); Serra do Boa Vista, Sao Jose, 24~X-1957, Reitz & Klein 5361 (LP); Marombas Curitibanos, 900 m, 29-X-1962, Reitz & Klein 13897 (LP); Cacador, Fazenda Carneiro, northeast of Cacador, 950-1100 m, 21-XII-1956, Smith & Reitz 8995 (US). Parana: Pinhaes in ruderatis, 835 m, 16-IX-1914, Dusén i i i ; ocira, 1 1 do Sul, 31-X-1958, Richter 4 B7828 (F); Aparados da Serra, : 24-X-1961, Pabst 6296 (LP). Brazil without locality, Sello s.n. (P). Sello 3840 (P). Although data are scarce for Perezia squarrosa, it appears that the species is usually found in humid places, in southern Brazil, Paraguay and Uruguay (Fig. 22-1), at low elevations or even at sea level. The populations which are included here in one taxon were formerly considered to constitute three distinct species: Perezia squarrosa from Uruguay; P. cubaetensis from southeastern Brazil; and P. laevis from eastern Paraguay. Collections from all of these areas are poor and consequently treatment of the taxa has been conservative. I have now seen collections from southern Brazil (Rio Grande do Sul and Parana) which show many intermediate characteristics between those found in plants from Brazil and those from Uruguay. Correlations of morphological characters with latitude and longitude indicate that there is a trend toward the northeast (toward Cubatio, Brazil from Montevideo, Uru- guay) for plants to become taller, more branched, and to have smaller capitula and larger leaves. In other words, although the Brazilian and the Uruguayan populations are disjunct, they ap- proach one another in morphology at the closest part of their respective ranges. In view of the allopatry of the two sets of popu- lations, and the discontinuity in morphology, I have treated them as subspecies. Although Baker (1884) placed Perezia laevis in the synonymy of P. multiflora, it seems to belong more naturally with P. squar- rosa subsp. cubaetensis because both share the features of small head size and lax flowering stems. In achene pubescence, foliar trichomes, and the reduced num- ber of involucral bracts, Perezia squarrosa is very similar to P. multiflora. Although the P. multiflora species group is a very tightly knit assemblage, there seems to be a closer relationship of 84 BERYL SIMPSON VUILLEUMIER P. squarrosa with P. multiflora than of either of these two species with P. kingii. Perezia squarrosa subspecies squarrosa differs from P. multiflora by having larger heads, fewer involucral bracts, and narrower leaves. The subspecies cubaetensis differs from P. multi- flora in its less spiny basal leaves, smaller capitula, and more open branching of the flowering stalk. 3. PEREZIA KiINGU Baker Perezia kingii Baker, Mart. Fl. Brazil. 6(3):380. 1884, Type: URUGUAY. Concepcién: Puerto de Salamanca, X-1875, Lorentz s.n. (Type destroyed at Berlin, Isotype GH). Very tall, weedy appearing rosette plant 18-91 cm tall with a long thick taproot. Stem terete in cross section, covered with a dense layer of glandular ine, clasping; up to 3 mm wide and 15 mm long, surface with multicellular glandular trichomes. Basal leaves sometimes acking, sometimes in de long, sometimes nodding. Involucre hemispherical, 9-13 mm wide, mm long, composed of 2 rows of brac uter bracts lanceolate, mucronate, stiff and shiny, with small white spines near the base; 1-2 mm wide, mm long, surface with grandular trichomes, non-scarious. long. Florets incons , white, and only slightly protruding from the involucre, oute ets mm long with ligules 1-2 mm long; about 10-14 flo mature achenes 2-3 mm long, densely covered with He silky blond or red double hairs. Mature achenes about 2 mm long. Recep- tacle covered with tufts of long blond or reddish trichomes around the point of ovary attachment. Distribution: along the western Bogen. aed border at sea level 1 r ative specimens: ARGENTINA. Entre Rios: Victoria, Victoria, 1-XI-1946, Meyer 10179 (LIL). Corrientes: X-1820, Bonpland 352 (P). Rio Colorado, IX-1904, Dinelli s.n. (BAB). unucuay. Banda oriental del Uruguay, 1816-1821, Catal 2312 (P). Florida: Cerro Colorado, Arroyo Timote, 15-X-1942, Gallinal, Aragone, Bergalli, Campal, Rosengurtt PE 5-334 (GH). Concepcién del Uruguay, Puerto de Salamanca, X-—1875, Lorentz s.n. (GH). Apparently, Perezia kingii is a fairly rare species. Collections are few, and it has not been recorded more than four or five times in this century. The collectors’ notes indicate that the species grows in sandy localities. The prevalence of collections from the THE SYSTEMATICS AND EVOLUTION OF PEREZIA 85 banks of the Uruguay River indicate that it is a riverine species. Because of its limited distribution (Fig. 22-1) and the scanty herbarium material, it is impossible to say whether P. kingii exhibits any geographical variation in morphological characters. n my opinion, there is no doubt that Perezia kingii is closely related to, but distinct from, P. squarrosa and P. multiflora. Along the banks of the Uruguay River it is sympatric with P. multiflora subsp. sonchifolia and P. squarrosa subsp. squarrosa. I have seen no specimens suggesting that hybridization has occurred. Perezia kingii is closely related to the other members of the P. multiflora species group as shown by the same type of dense copper or blond double trichomes on the achenes, the pubescence on the receptacle, the reduced number of rows of outer bracts, and the small pollen size. However, the very small capitula size is a unique character of Perezia kingii allowing it to be readily distinguished from the other members of the P. multiflora species group. The many heads, loose branching, and the pure white pappus are also unique to P. kingii. These characters are suggestive of some species of Leucheria and Trixis. 4. PEREZIA PRENANTHOIDES Less. Perezia prenanthoides Lessing, Synop. Comp. 409. 1832. Type: CHILE. Bio Bio: Andes de Antuco, Valle de Quilai, II-1830, Poeppig 923 (P, Iso- Stems terete, variable in pubescence, but usu with increased amoun of glandular trichomes near the inflo nce; m treaked Stem leaves about four up to the point of the first branching, numerous above; lower leaves lyrate, parted with the segments dentate, clasping, u to 2.5 cm wide and 7 cm long; decreasing in size until almost scale-like under the ultimate branchlets. Basal leaves lyrate or runcinate, parted wi dentate segments, acute, attenuate at the base, 4-13 cm , 12-40 cm long, glabrous to slightly pubescent with the scattered glandular trichomes denser along the veins of the under surface of the leaf blade. Inflorescence a flat topped cyme of 3-25 heads; only one flowering stalk per rosette. Indi- i 4 i c 86 BERYL SIMPSON VUILLEUMIER deep ) in color, 10-16 mm long. Florets rose, pink, or maroon; outer florets 1.5-3.3 cm long with ligules 4-15 mm long; about 31 per head. yes: es and teas es with scattered stacks trichomes; sometimes with a scat- tered onary hairs at the top. Receptacle convex with a few icettene silky tri chom : ; u Comber 1064 (K). Rio Negro: Parque Nacional Nahuel Huapi, near Lagun los Clavos, 19-III-1949, Lourteig 267 (P), Cerro aoe bs II-1965, Vuillew mier 185 (GH), 9-II-1965, vishal 191 (GH). cue. Bio Bio: Andes de Antuco, Valle de Quitai, Poeppig 92 3 (P). Malleco: Cordillera de Nahuel- buta, Fundo Solano, Los Alpes, 2000 m, 13-I-1958, Eyerdam 10163 (F, ); before the city of Lonquimay, 31-ITJ-1965, Vuilleumier 221 (GH); Volean de Tolguaca, 24-II-1925, Pennell 12790 (GH); Cordillera Las Raices, 2-III-1939, Burkart 9574 (SI). Cautin: Volcan Llaima, 1200 m, TI- 1927, Werdermann 1230 (F, GH, HBG, NY, SI, US); Temuco, Refugio, 3-II- 1961, Ricardi & Matthei 5318/122 (CONC): Boquete de Trancura, II-1887, O. Philippi s.n. (SGO), re ag Nab Cerro Vichadero, Casa Pangue, 14-I-1953, Pfister s.n. (CONC). * Heads nodding » @ heads upright at 4 (P NUTANS) : A * 3 e * PRs sal oe 2 * : ¥ x — % a 6 * : “9 3% : a * * ea oe Ld 3°. PRENANTHOIDES) * 0 . _ es 10 is 20 Length of inner bract in cm. Fic. 19. Graph of inflorescence vs. a Sens length of Perezia prenanthoides — poet ns Sans the neat separation of t two very closely ae species of t P. prenanthoides species group. Each s — Gsaan one specim THE SYSTEMATICS AND EVOLUTION OF PEREZIA 87 %* P PRENANTHOIDES ® P PEDICULARIDIFOLIA xX P LYRATA = .@) z i * 2 Ww = Plant height - — - 5 “~~ Leaf width -——-—- Leaf length ~~~ ui = oe aang ak. mos ore ™ : — x + ais - -— po Qa er et —-——-- 26 Se a a! A i eS ee DEGREES OF LATITUDE SOUTH G. 20. Graph of plant height, leaf length, and leaf width vs. latitude of three species of Perezia inhabiting the Nothofagus forest of southern South America. The graph shows these three species are found in populations between 37° and Throughout the Nothofagus forest in the lake region of Argen- tina and Chile, Perezia prenanthoides is a conspicuous plant (PLATE 1-4) in the early summer. Its showy clusters of magenta heads are visible in patches in the higher elevations of the forest along with Chusquea (a bamboo) and, in several places, with the smaller, blue-flowered P. pedicularidifolia. Reiche distinguished the two species, Perezia prenanthoides and P. brachylepis (treated here as one taxon) on the basis of the width of the outer bract and the length of the inner bracts relative to the length of the florets. There is a discernible trend for plants to become gradually smaller (in all dimensions ) as one goes south in the range (Fig. 20). It is noteworthy that the type specimens of P. prenanthoides and the synonym P. brachylepis are from the extreme ends of the range and were described at a time when intermediate specimens might not have been available. 88 BERYL SIMPSON VUILLEUMIER The two species, Perezia prenanthoides and P. nutans form an isolated species group within the South American Perezia. Their similarity in habit, morphology, and ecology, however, suggests that they are only recently differentiated from one another. That they have attained specific rank is attested to by a large amount of sympatry in their ranges without apparent hybridization and by several distinctive characters. Figure 19 graphically shows that the two form well defined taxa on the basis of involucral bract size and the type of branching of the flowering stems. Perezia prenanthoides has a compact branching habit which produced an arrangement of heads similar to a cyme. The individual heads are small, upright, and hemispherical. In contrast, P. nutans has a loose, paniculate arrangement of heads and nodding, turbinate capitula. Because of its large showy inflorescence of pink flowered heads (PLATE 1-4), Perezia prenanthoides is almost impossible to con- fuse with any other speices of Perezia except P. nutans. The only species to which it is vaguely similar are those of the P. multiflora group. Species of this assemblage, however, have spiny foliage and achenes densely covered with copper colored double tri- chomes whereas both P. prenanthoides and P. nutans have soft leaves and achenes with glandular trichomes. 5. PEREZIA NUTANS Less. Perezia nutans Lessing, Synop. Comp. 409. 1832. Type: cumLe. Antuco, Meseta de Antuco, I-1830, Poeppig 896 (P, Isotypes GH : Perezia gayana de Candolle, Prodr. 7:63. 1838. Sel. Icon. 4:tab. 94. 1839. Type: . pe G). Perezia perfoliata Remy in Gay, Fl. Chile 3:415. 1849. Type: CHILE. Colchagua, Cordillera de San Fernando, Gay s.n. (P, Isotypes F, GH, NY, US d t smelling flowers. Plants 24-84 cm tall. Stems terete, frequently slightly striated, sometimes with a reddish tinge and usually with some glandular trichomes, especially near the inflorescence. Stem leaves 2-5 to the point of n teeth secondarily dentate, attenuate at the base; 2.5-10 cm wide, c long; a few scattered glandular trichomes usually present on the surface and ur Individual capitula turbinate, 1.9-4.2 cm wide and 1.7-3 cm long. Involucre turbinate, 1.5-3.7 cm wide, 1.5-2.2 cm long; composed of 3-5 rows of bracts. Outer bracts ovate or lanceolate, acute, entire, 1-3 mm wide, 4-16 THE SYSTEMATICS AND EVOLUTION OF PEREZIA 89 mm long; usually green but sometimes with a slight reddish tinge; non scarious. Inner bracts lanceolate to linear-lanceolate, acute, 1-5 mm wide, 8-22 mm long, green and slightly scarious along the edges. Pappus setose, specimens seen. Distribution: Valparaiso in central Chile to Malleco, eastward in Argentina in the province of Neuquén (Fig. 25-4). Altitudinal range from 1200-2500 71°04’W, 1300 m, 15-I-1964, Ibid 10885 (LP). cue, Valparaiso: Cerro Campana, 1200 m, 17-I-1939, Morrison & Wagenknecht 17142 (GH), Hastings 490 (NY, US). Colchagua: Cordillera de San Fernando, Gay s.n. (F, GH, P, US); Baiios del Flaco, 19-XII-1938, Moreau 23469 (LP). Nuble: Termas de Chillan, 1800 m, Cabrera 3629 (LP), Cuesto de Pirigallo, 20-II-1958, Codero s.n. (CONC), Lecheria, 11-II-1960, Pfister s.n. (CONC), rocky cliffs, 1800-1900 m, Pennell 12380 (F, GH, NY, US), 1800-1900 m, 31-III-1965, Vuilleumier 223 (GH). Bio Bio: Cordillera de Bio Bio, Cerro del Padre, 11-II-1939, Barros 2632 (SI); south of Laguna de la Laja, las Cuevas, 26-XI-1941, Behn s.n. ( CONC); Antuco, Huingan, 15-I-1941, Junge 2429 (CONC, LP), I-1830, Poeppig 896 (G, NY, P). Malleco: Lonquimay, Laguna San Pedro, 3-II-1953, Pinto s.n. (CONC). Like Perezia prenanthoides, P. nutans is a woodland species inhabiting the upper reaches of the Nothofagus forest (Fig. 25-4). In the northern part of its range, Valparaiso and Santiago, it inhabits more open areas than further south. Old illustrations indicate that, until very recently, there was more forest in the upper valleys of rivers in the Santiago region than today. Conse- quently, the distribution of P. nutans has probably been recently constricted. The populations which I feel should be included in Perezia nutans were formerly considered to be three species: P. nutans, P. perfoliata, and P. gayana. Reiche maintained all three species in his Flora de Chile and distinguished the species on the basis of the density of the stem pubescence and by the “shape of the stem leaves. The amount of pubescence is extremely variable in almost all species of Perezia and is not a character of specific value. The “shape” difference utilized by Reiche is actually a difference in 90 BERYL SIMPSON VUILLEUMIER leaf width rather than an actual shape difference. The size and broadness of the leaves of Perezia nutans appears to vary with the amount of sunlight, exposure, and moisture. There is an in- crease in leaf size from north to south as the rainfall and forest cover increases. Although Perezia nutans is very similar morphologically to P. prenanthoides, it can be separated on the basis of the inflo- rescence type and the outline and direction of the heads. Figure 19 shows that a combination of these two characters clearly sep- arates the two taxa involved. 6. PEREZIA PUNGENS (H. & B.) Less. Chaetanthera pungens Humboldt & ag gs Pl. Aequin. 2:146. Planche 127. 1809. Type: Ecuapor. Pichincha: Pichincha near Quito, without collector (P, in the Humboldt Herbarium omanthis pungens (H. & B.) H eaicldt Bonpland & Knuth, Nov. Gen. 820 Clarionia pungens (H. & B.) D. Don, Phil. Mag. il, 388. Drozia dicephala Cassini, Opus. Phytol. 2:171. 1826. From the pic i Cassini’s specimen belongs in synonymy with Perez ngens r, Cassini cited no type and I can find no specimen “labeled ait dis name. Homoianthus scaber Bentham, Pl. Hart. 136. 1844. Type: in the moun- tains of Gua ibamba (which I assume is in Peri or Bolivia). OF page 353 of the same work (1857), Bentham stated in the errata that the species H. scaber was synonymous with Perezia pungens. I have not seen Bentham’s e. Clarionea macrocephala Schultz-Bipontinus in Lechler, Berb. Amer. Aus 57. 1857. This name was a nomen nudum and thus 0 validly ablished. Tovar's transferral of the name to Perezia in 1955 is also, therefore, not valid. Leucheria fasciata Klatt, Engl. Bot. foomy 8:51. 1886. et ECUADOR. Pichincha: Mt. Pichincha, 4000 m, 4-I-1881, Lehman 386 (G Perezia elongata O. Kuntze, Rev. Gen. 3(2),168 1898. ie. ‘BOLIVIA. Cochabamba: on the road between oe and Rio Juntas on the m, . ee aubeld pier Laat Engl. Bot. Tae ‘21: 372. 1896. Type: PERU Pacamayo a i Mayobamba, 3650 m, Stubel 34 (types ei . Perezia pungens (H. .) Less. var cernua Rusby, Mem. Torrey Bot. Club 6:70. 1896. Type: sotivia. Cochabamba: Mt. Tunari, 1891, Bang 1049 (NY, Isotypes GH, Perezia ee 396 Siecpa: ex Domke, Notizbl. Bot. Gart. Berlin 13:249. 1936. Type: . Puno: Sandia, above Cuyocuyo, 3800 m, 3-V-1902 Weberbauer 933 | (C ). Perezia aracensis Koster, Blumea 5:678. Figure 7 a-d. 1945. Type: BOLIVIA. Araca, 4400m, XII-1910, Bock 2480 b (type not seen). THE SYSTEMATICS AND EVOLUTION OF PEREZIA 91 Perezia obtusisquama Koster, Blumea 5:680. Figure 7 k-o Type: BOLIVIA. Cochabamba: alpine meadows above Tablas, V-1911, psu 2163 (type not seen, Isotype Perezia fosbergi Tovar, Pub. Mus. Hist. Nat. Lima Bot. 8:22. Figure 9. 1955, Type Cajamarca: Celendin, Las Lajas, northwest slopes of Cerro Alto, euitienst of Cortagama (Chimuch), 35 km north-northeast of Celendin, 3500 m, 3-VI-1947, Fosberg 28123 (USM, Isotype F Perezia conaicensis Byes Pub. Mus. Hist. Nat. Lima Bot. 8: 31. Figure 14, 1955. Type: PER . Huancavelica: Huancavelica Con naica, Laria, 8 km southwest of hated, "3900-4000 m, 30-III-1952, Tovar 903 (USM, Iso- e stem, lanceolate to stipe, acute (obtuse Cae: Peri and no Bolivia), entire or dentate, clasping, often aoedate at the base, vay vaitabe in size; surface with a variable — of glandular trichomes. Basal leaves in a loose rosette (except in e plants in Cajamarca, Pert) or, rarely, shriveled at flowering time, Lincadhihs to aliptical uneven teeth, more rarely spiny or entire; petioled for about one-half the length of the leaf or clasping; 6-50 mm wide, 4.5-40 cm long; usuall densely pubescent. Plants monocephalous or more rarely with up to 9 heads per ms hegg stem and up to 14 per rosette. Capitula c campanulate, 1.5-5 or ayien at ie m wide, 5-22 mm ong; so: often with reddish streaks. Inner ree lanceolate, — gaan or icahe serrate at the apex; 1-5 mm wide, 1-2.5 cm long. Pappus setose, brown, 6-20 mm long. “Florets white, aa. violet or pinkish the inner two petals of than cm long with ligules 5-20 mm long; from 10.68 florets per capitulum. Im- mature achenes 1-4 mm long, “8 a variable — of glandular trichomes. Mature achenes to 4 mm in length, surface as in the ovaries. Receptac cle rous. Chromosome number: Pichincha, Ecuador, n=12. Distribution: from southern Colombia through Ecuador, Pert and into northern or central gh (Fig. 21). Apparently in wet, fairly tall pun grass. Altitudinal Aims m 2500-4600 m. Flowering from February to ‘See Pp Sisecne eo specimens: coLoMBIA. Pasto: 3200 m, Triana 1511 (P). EcuADOR. Imbabura: Lake Cuicoc “ti 3300 m, 28-V-1939, Pentland & Sum- 25° 739 (F); northeast slope of Cayambe mountain, 14500 ft, 16-XII-1961, azalet & Pennington 5780 (NY): row of Cotachi peak, 4400 m, 31-V- 1099, Pentland ¢& Summers 8021 (F); above pee selva Alegre, west of Otavalo, 11200 ft, 23-IV-1944, Drew E-143 (U S). —— 18-VIII- a4 po-P tisana Antisana, 4100 m, 21—VII-1960, Grubb. Lloyd, Pennington dr uieor 574 (NY); near Los Llanganti between Aicilibi and Rio Potero east of Roma Paramo, 3600 m, Serbage sire & Juajibioy 9203 (US); Cotopaxi, Cordillera Occidental Paramo de Apagua between Zumbagus and Pilalo, 3800 m, 18-19_VII-1959, harckeg d Juajibioy s.n. (US). Chimborazo: Hacienda agna east 0 Chunchi, Paramo de Cachea 2 m, 27-VII-1959, Barcla: & Juajibioy 8284 (US). PERU. gaaarce: umullca, 20-V-1965, Vuil- 92 BERYL SIMPSON VUILLEUMIER leumier 251 (GH); Celendin, 3700 m, 6-X-1958, Ferreyra 13277 (GH). mazonas: Chachapoyas, upper slopes and summit of Cerro Campanario, 3600-3900 m, 3-VII-1962, Wurdack 1560 (US). La Libertad: Patdz, entre Hirsch 12082 (NY). Junin: Yauli, 13500 ft, Macbride + Featherstone 925 (F). Cuzco: Calea, Pisac, 4000 m, II-1950, Marin 1898 (F); Paucartambo, Acjanacu Pass, 9-V-1965, Vuilleumier 250 (GH); Marachea hills of Esca- lerayoc, 3700-4200 m, 31-VII-1939, Vargas 11180 (F); Pillahuata, VIII- 1939, Herrera 3335 (US); Chubamba, 3800 m, 4-III-1962, Diaz 2034 (LP); Paso Tres Cruces, Cerro de Cusilluyoc, 3800-3900 m, 3-V-1925, Pennell 13884 (F, GH, NY, US); amba, lomas de Puyupata, 3000-3800 m, ? 2 r III-1942 Vargas 2730 (LP). sorivia. La Paz: La Fabulosa, 15000 ft, above the valley, Brooke 6299 (BM): Larecja, Sorata, 3300-3800 m, Mandon 25 (F, GH, K, NY, P). Cochabamba: plateau, Mt. Tunari, 1891, Bang 1049 (GH, NY, US); Choro, Aparcita, 12400 ft, 3-II-1950, Brooke 6100 (BM, F, NY); road to Chimore, 3000 m, V-1939, Cardenas 765 (US); Chapare, 3100 m, 9-III-1929, Steinbach 9562 (GH). Oruro: Espirito Santo, 1891, Bang 1218 (G, GH, NY, US). There is considerable variation in Perezia pungens from its northern limit in Colombia to its southernmost populations in Bo- livia. The populations originally described as Chaetanthera pun- gens by Humboldt and Bonpland occur from Colombia through southern Ecuador, growing on volcanic peaks in tall, wet grass. Morphologically, although very variable, plants from these areas are large and have leafy flowering stems. The species has been described as being monocephalous, but there are now numerous specimens with polycephalous flowering stems from Pichincha, Ecuador and surrounding mountains. Plants with cernous capitu- la are frequently encountered in this area. The leaves, stems, bracts, and achenes of the Ecuador populations are almost with- out exception covered with glandular trichomes. Although the basal leaves are usually petioled, numerous examples can be found with clasping basal leaves. Populations described as Perezia stubelii by Hieronymus are found on the moist, east facing slopes of mountain passes (jalcas ) in the Department of Cajamarca, northern Peri. These plants supposedly differ from P. pungens because they have clasping basal leaves and strigose (double hairs ) trichomes on the achenes. However, examples of P. pungens which are very similar to these plants can be found in Ecuador. Thus it appears that the “jalca” populations are merely isolated, and slightly different, forms of P. pungens. THE SYSTEMATICS AND EVOLUTION OF PEREZIA 93 Further east in Cajamarca is another species, known from only two specimens. These rather bizarre plants, described by Tovar as Perezia fosbergii, are much larger than any previously known specimens from this area. They are paniculately branched with numerous heads. Analyses of the pollen diameter and stomata size indicate that these plants are not polyploids. Since the description of P. fosbergii, other collections have been made still further east in the Department of Amazonas (Pert). One speci- men I have seen (Wurdack 1560) is as large as those described as P. fosbergii, and has a rosette of clasping, evenly toothed leaves, but is monocephalous. The presence of these newly collected populations indicates that P. fosbergii, like P. stubelii, is referable to P. pungens. Tovar described another species in 1955 from central Pert (Huancavelica) which he called Perezia conaicensis. When a large series of specimens of P. pungens is examined, it is evident that the type of this putative species falls completely within the range of variation of the former and I can therefore see no reason to maintain it as a species. In the extreme south of Pert, on the wet passes in Cuzco, there are several populations (rapidly disappearing because of the spread of farming) which have long been known as Perezia macrocephala (an invalid name). Plants from these populations are readily recognizable because of the smooth, entire leaf and bract margins and the large capitula. Yet, except for the entire leaf margins, these plants are indistinguishable from some Ecua- dorian specimens. Thus they appear to be a form of P. pungens which has become isolated in the high, moist mountains of south- eastern Peri. Moreover, the Cuzco populations are intermediate in morphology between those in northern Peri and those in north- ern Bolivia, which were described as P. pungens var. cerna by Rusby in 1896. Rusby’s comment, following the description, sum- marizes well the confusing situation found throughout this species: [this variety] . . . “presents some characters strikingly different from those of the type [of P. pungens] but I can not establish specific distinctions.” The most conspicuous difference between Rusby’s and the typical variety is the presence of nodding heads and deep red-colored bracts in var. cerna. Again, both of these characters can be found in specimens from Ecuador. Smooth margined bracts, also present in Rusby’s Bolivian plants, 94 BERYL SIMPSON VUILLEUMIER ie oF ice aca: mama Fe oo |p PUNGENS ” Id Pte 2 Les = P CILIARIS ¥* i Agee Oa P. CARDUNCELLOIDES eo. = ra a | | eX . Distribution of Peresia pungens, P. ciliaris, and P. carduncelloides. Arrows Tea ee at which intermediate specimens have been collected. THE SYSTEMATICS AND EVOLUTION OF PEREZIA 95 are found in the Cuzco populations discussed above. The type specimens of two other epithets, P. elongata O. Kuntze and P. obtusisquama Koster are taxonomically the same as Rusby’s P. pungens var. cerna and they have been included under P. pun- ens. In the Andes, the climate becomes drier south from Ecuador to Pert until, in central Bolivia, the only remaining humid areas are a few east facing slopes. The high puna (except for bogs, which are a specialized microhabitat ), which covers most of the central Peruvian peaks and all of the altiplano, is exceedingly dry and covered with short grass. Correspondingly, Perezia pungens which seems to inhabit humid slopes, especially those with tall grass, becomes rarer toward the south. Apparently it is replaced by a second, but very similar species, P. ciliaris. It appears that in an area of climatic change at the Ecuador-Pert boundary (where the dry upper Marafion creates a sharp dividing line), these two species hybridize. It is possible that P. pungens and P. ciliaris are merely ecotypes of the same species, and that the intermediate specimens simply reflect a stepped-cline type of variation in an intermediate habitat. Yet, the peculiar distribution of P. pungens discussed above and the very distinct habitats preferred by each of the species reinforces the interpretation that they are different taxa. Morphologically, the two are generally separable because P. ciliaris has glabrous bracts, achenes, and leaves (or at the most only sparsely pubescent). The edges of the outer bracts are also stiff rather than soft as they are in P. pungens, and many speci- mens have sharp spines along the edges. (Compare PLATE 1-1 with 1-2.) The following specimens are representative of those found at the Ecua- abt Pavivins border and which are intermediate in morphology, and, therefore, are presumed to be hybrids i Piese ngens and P. ciliaris. Ecuapor. Chimborazo-Caiar: border near E] Tambo, 10000-11500 ft, abbey ot Camp E-4093 (NY, US). Cafiar: neal E] Tambo, 9500- 1 22-IV-1945, Camp E-2808 (NY). Azuay: Valley of the Rios Paute an Cuenca, 7200-8000 ft, 13-IV-1945 Camp E-2572 (NY). 7. Perezia citraris D. Don ex Hook. & Arn. Perezia ciliaris D. Don ex Hooker & Arnott, Comp. Bot. Mag. 1 835. Lectotype chosen: “CHILE,” Dombey s.n. (P, G). Hooker & Amott 3 aid not cite a specimen, and obviously took their description from a man t of D. Don. They stated that they believed the type to be a Cuming ects 96 BERYL SIMPSON VUILLEUMIER (not a Dombey ). However, I could find no specimen annotated by eon D. Don, or Hooker & Arnott either at Kew or the British Museum. I therefore. chosen the Dombey specimen cited by de Candolle as type. i is doubtful if the specimen rege comes from Chile as it - now known. 22 alpen ciliaris (H. & A.) de Candolle, rade, 7:61. Homoeanthus nivalis Philippi, Anal. Univ. Chile 87: ne 1894. non Perezia ssiualle Weddell. Type: sotivia. Oruro: Chayanta between Oruro Perezia foliosa Rusby, Mem. Torrey Club 6:71. 1896. Type: BoLivia. Bolivian Plateau, Turedon, 1891, Bang 1131 (NY, Isotypes i Perezia scapellifolia Koster, Blumea 5:680. Fi igure 7 e-i, 1945. Type: BOLIVIA. Cochabamba: high mountain meadow nea S Calpe 2800 m, IV-1911, Herzog 1915 (type not seen, Isotype LP). Perezia scapellifolia Koster var. pa arvifolia Koster, Blumea 5:680. 1945. Type: BoiviA. Coc ee ie mba: Cerro Sipacoya, 3900 m, IV-1911, Herzog 1915 bis (type not s Perezia coriacea Tavad, ‘Pub. Mus. Hist. Nat. Lima Bot. 8:21. Figure 8. 1955. Type: PERU. Hudnuco: Mitotambo, above Mito, 3000-3200 m, 24—VI- 1953, F ‘sil 9431 (USM, Isotype GH Cau escent, more or less glabrous herbs 10-50 cm tall. Stem leaves scat- tered up the stem, lanceolate in outline, acute to mucronate, dentate, ciliate, or spiny, clasping. Basal leaves in a loose rosette, petiolate, lanceolate to elliptical, acute, dentate or spiny, or with uneven teeth, 2-5 cm wide, 5-20 binate, 1-2 cm wide, 1-2 cm long; composed of 3-6 series of bracts. Outer bracts lanceolate, acute, serrate or spiny, or, more rarely, merely stiff with entire margins; 3-4 mm wide, 5-15 mm long, scarious. Inner bracts lanceo- late, ane, entire; 1-4 mm wide, 1-2 cm long. Pappus ne brown, 5 from 10-40 orets per capitulum. Immature achenes 1-4 mm long, glabrous or with a few scattered strigose or pete ae a glabrous. Chromosome number: Tucuman, Argen of Azogues sn streams, "3000 m, ‘Sates Fosberg '& Prieto gerne . 0-80! m, 13-IV-1945, Camp E-2572 (GH). peru. Piura: Huancabamba, 8000- 9500 ft, 26-IV-1911, Townsend A215 (F). La ok Llantobamba, 4 iL i VI-1950, Lopez 480 (US). Ancash: Yungay, Llanganuco, 3500-3800 m, Ferreyra 14357 (GH); entre Casquitambo y Conococha, 3000-3200 m, 24-V-1962, Ferreyra 14459 (GH). Hudnuco: Hudnuco, arriba de Mitotambo entre Hudnuc co y Chavinillo, 3000-3200 m, 24-VI-1953, Ferreyra 9431 (GH); 15 km east of Huanuco, 1-VI-1922, Macbride dF eatherstone 2116 GH). : V c bri 1258 (GH, US). arcentina. Jujuy: Yumbaya, Voledn, 3-II-1929, Venturi 9173 (US). Salta: Oran, Cerro Queso Asintado, 3100 m, 27-III- 1945, THE SYSTEMATICS AND EVOLUTION OF PEREZIA 97 Pierotti 1054 (LIL). Catamarca: Andalgala, 10-II-1947, Jorgensen 1383 (US); Belén, Las Faldas, Sierra de Belén, 2500 m, III-1938 Schreiter s.n. (A, LIL), faldas norte de Portezuelo del Rio Blanco de Granadillas, 3100- 3300 m, 29-I-1952, Sleumer & Vervoorst 2588 (US). Tucuman: Sierras Calchaquies, La Puerta, 30-I-1933, Burkart 5207 (SI), Quebrada de los Alisos, Casa de Piedra, 19-XII-1907, Castillon 101 (A), El Alazan del Valle, 3200 m, II-1912, Castillon 2911 (A, LIL), Quebradas del Barén, 3300 m, 7-II-1958, Fabris 1382 (GH), Cerro Negrito, 3500-3600, 26—-II-1949, Sparre 6139 (LIL), Cerro San José, 3000 m, 11-II-1925, Venturi 3623 (US), Infiernillo along the road to Amaicha, IV-1965, Vuilleumier 226 (GH); Chicligasta, Est. Las Pavas, 3200 m, 12-III-1924, Venturi 3081 (LP, US); Pto. La Cueva, Santa Rosa, 3600 m, III-1924, Venturi 3201 (GH); Cumbre de Malmala, 3300 m, 3-IV-1904, Lillo 3429 (A). La Rioja: Sierra Famatina, Laguna Moradita, 13-III-1907, Kurtz 14601 (CORD), Mina San Juan, 3050-3200 m, 11-II-1906, Kurtz s.n. (CORD). Mendoza: Villa- vicencio, 27-II-1942; Burkart, Troncoso, Nicora 14416 (SI), Las Heras, 18-I-1943, Corvas 866 (SI); Cancha de Esqui, 3000 m, 3-II-1950, Cuezzo & Say 2518 (LIL). The series of populations included here in Perezia ciliaris is very similar morphologically to those of P. pungens except that plants of the former tend to be stiffer, less pubescent, and to have more narrow, frequently spiny involucral bracts (PLATE 1-1 and 1-2). The heads of individuals of P. ciliaris also tend to be smaller than those of P. pungens and, correspondingly, have fewer florets. As mentioned above, an area of hybridization or transition can be seen between these two species in southern Ecuador-northern Perti where the soft, densely pubescent plants of P. pungens are replaced by rigid, almost glabrous plants of P. ciliaris. The distribution of Perezia ciliaris is in dry areas from southern Ecuador to northern Argentina. However, the range is not con- tinuous but rather composed of small populations isolated in various valleys. The morphological discontinuity frequently seen between individuals from different populations is probably due to limited gene exchange between these disjunct localities. Al- though described as distinct species in some cases (i.e., P. foliosa Rusby, P. scapellifolia Koster, P. coriacea Tovar), it seems better to consider these populations as allopatric populations or local races of one variable species. In addition to the apparent hybridization in the north with Perezia pungens, P. ciliaris seems to hybridize in Argentina with P. carduncelloides. These two species are also very similar mor- phologically, but they can be distinguished because the latter has large, foliaceous outer bracts which obscure the inner bracts, and yellow or violet florets (compare PLATE 1-2 with 1-3). Plants of 98 BERYL SIMPSON VUILLEUMIER P. carduncelloides appear to grow in more moist habitats than P. ciliaris. Specimens of intermediate morphology between Perezia ciliaris and P. carduncelloides include: arceNtiNa. Jujuy: Est. Volc4n, Abra de Corte, 2500 m, II, Jorgensen 1383, 1383A (GH); Loma Negra, 3000 m, 24-III- 1934, Pierano s.n. (A). Tucuman: Tafi, Macho Rastrojo, 3000 m, 16-II- 12-III-1924, Venturi 3081 (LIL). La Rioja: Sierra Famatina, Cuesta de la Tamberia, 7—III-1907, Kurtz s.n. (CORD). 8. PEREZIA CARDUNCELLOWES Griseb. u : Cienega, Lorentz 320 (photo at GH, Isotype CO Tall, leafy herbs 1 cm tall. Stem leaves numerous, sca p stem, lanceolate in outline, acute, dentate, clasping and sometimes sli cordate at the bas ht green, surfa few scattered glandular tri- chomes. Basal leaves usually withered at floweri g time; when present, few in number, lanceolate, petioled, dentate, sometimes with a few scattered glandular trichomes; wide, 5-15 g. Plants with 1-7 heads per owering stem and up to 20 heads per plant. Capitula turbinate, 1. c wide, 1.2-3 cm long, upright. hivdiise turbinate, 1-2 cm wide, 1- long; composed of 3-7 rows of bracts. Outer bracts foliaceous, lanceolate, acute or slightly obtuse, dentate, 1-7 mm wide, 6-22 mm long; soft; ually ith a few scattered glandular trichomes. Inner bracts lanceolate, acute, entire; 1-3 mm wide, 1-2.5 cm long; stiff, scarious. Pappus setose, brown, 3-3 cm long with 1904, Fiebrig 3157 (GH, NY, P, US). ARGENTINA. Jujuy: Tumbaya, Volcan, subida al Cerro Abra Morada, 2600-3200 m, 5-III-1965, Cabrera & Solbrig iguez 421 (A); Salta: Candelaria, Sierra de la Candelaria, 2500 m, 18-V-1925, Venturi 3757 ‘ GH, SI, US). Catamarca: Yulayaco, 3500 m, II-1916, Jorgensen 1380 (GH). In southern Bolivia and northern Argentina the ecological counterpart of Perezia pungens is P. carduncelloides. Althou specimens are rare, label data indicate that the species frequents moist, grassy slopes as does P. pungens in Ecuador and Pert. As is the case also with P. pungens and P. ciliaris, P. carduncelloides has a range composed of a series of disjunct populations isolated by areas of inhospitable terrain. In areas of southern Bolivia an THE SYSTEMATICS AND EVOLUTION OF PEREZIA 99 northern Argentina where the dry valley bottom habitats meet the upper, wetter grass-covered slopes, P. carduncelloides appears to hybridize occasionally with P. ciliaris. All of the three species of this complex, P. pungens, P. ciliaris, and P. carduncelloides are similar morphologically and form one of the most confusing tax- onomic situations of the South American Pereziae. In some ways, it might be better to consider them semispecies as defined by Mayr (1963, p. 671) but only further field studies or experimental work can show whether it would be more meaningful biologically to consider them subspecies rather than distinct species. Morpho- logically, P. carduncelloides differs consistently from the other two taxa in having a paniculate, flat-topped arrangement of heads with usually yellow or violet (rather than blue) florets. The most characteristic feature of P. carduncelloides is, however, the pres- ence of very large foliaceous bracts that resemble the uppermost stem leaves. Both related taxa have lanceolate outer bracts defi- nitely smaller than the inner bracts (compare PLATES 1-1 to 1-3). 9. PEREZIA SUBLYRATA Domke Lima Bot. 8:11, 1955. Type: perv. Cuzco: Paucartambo, near Quencomayo Ponte Colquipata, 3200-3300 m, 1-V-1925, Pennell 13789 (GH, Isotypes F, Decumbent Stem terete in cross section, slightly striated and sometimes reddish in color; sometimes with scattere qd i lum. Stem leaves 2-9 scattered up the stem, slightly spathulate in outline, s outline, rounded at the apex, dentate with large blunt segments, shortly petioled; width 7-26 mm, length 5.5-21 cm, surface with some g r trichomes. Flowering stems monocephalous, decumbent or infrequently up- i rosette. Capitula narrow ay P campanulate, 1-3.5 cm wide, 1.5-2.5 cm long. Involucre elongate, round i ; com of 4-7 rows of 4 mm wide, 14-20 mm long, glabrous or wi trichomes at the apex; broadly scarious; dark green in the center or slightly reddish in color. Pappus 6-18 mm long, setose, whitish-yellow in color. Florets blue or white; outer florets 1.6-3 cm long with ligules 5-15 mm long; from 18-30 per capitulum. Immature ovaries 2-3 mm long, very slightly 100 BERYL SIMPSON VUILLEUMIER pubescent, or with a fairly dense coating of double hairs. Mature achenes dark brown with a few scattered double hairs; 3-4 mm long. Receptacle cazgues convex with a very few glandular trichomes sometimes scattered on es Distribution: from mid Peri in the province of La Libertad south to northern Argentina in Jujuy (Fig. 22-3). Altitudinal range 3000-5000 m. Flowering from December to M Representative u. La Libertad: Huamachuco, Llantobamba, 4100 m, II, Infantes 3676 (LIL). Junin vicinity of La Oroya, 13000-15000 ft, Kalenborn 115 ( , US). Huancavelica uancavelica, Santa Rosa J 4398 (P); northwest of Azdngaro, 3900 m, 1-V-1965, Vuilleumier 246 (GH); Lampa in Polylepis association, 4000 m, 2-IV-1951, 4000 m, 2-IV- 1951, Raute & Hirsch s.n. (NY). orivia. La Paz: Cerro Quimsachata, 13 south of Tiaguanaco, 4100 m, 31-III-1936, West 6390 (GH): Larecaja, Sorata, 3100-3800 m, V-1858-1860, Mandon 23 (NY, P); 80 km north of La Paz, Mina La Fabulosa, 3-IV-1950, Brooke 6299 (F, LP); General Campera, 4000 m, 4-III-1921, Asplund 4900 (US). Chilcani, 3500 m, 2-V-1858, Mandon s.n. (P); Marcarmarcani, Mandon s.n. (P). ARGENTINA. Jujuy: Tilcara, subida de la Abra de Remante, 4150 m, 25-II-1953, Sleumer 4075 (LIL). From the specimens available for study, the distribution of Perezia sublyrata appears to be very discontinuous (Fig. 22-3). More collecting at high elevations in the intervening area will show whether or not the species is actually continuous across southern Pert and Bolivia. It is possible that part of the present disruption of the range is due to farming and sheep ranching on the altiplano. I have seen sheep grazing plants of this species in southern Pert (Azdngaro), and the Indians there say that plants grow only in the parts of the hacienda which are inaccessible to animals, or have too little vegetation for grazing. The species most similar in morphology and most closely re- lated to Perezia sublyrata is P. pungens. The primary morpholog- ical characters which separate the two species are the habit and the involucre. Plants of P. sublyrata are usually decumbent while those of P. pungens are upright, except in Huancavelica, Peru, where the populations of P. sublyrata appear to have numerous upright plants. The capitulum of P. sublyrata is also much more elongate than that of P. pungens and the bracts of the involucre form a pattern of dark green and white in P. sublyrata because of the overlapping of bracts with dark green centers and white scarious margins. Finally, the basal leaves of P. sublyrata are THE SYSTEMATICS AND EVOLUTION OF PEREZIA 101 P KINGI] & P SQUARROSA subsp.SQUARROSA subsp. CUBAE TENSIS ®& P SUBLYRATA P CILIOSA ( (/ 22. Distribution of Perezia kingii mulsifiora species group, and P. mandonii, FP. pungens group. sublyrata, and P. squarrosa, both members of the P. and P. ciliosa, all of the P. 102 BERYL SIMPSON VUILLEUMIER lyrate with rounded segments and a large terminal segment. The leaves of P. pungens are usually lanceolate, although some popu- lations in northern Bolivia have sublyrate leaves. 10. PerEziA MANDONI Rusby Perezia mandonii Rusby, Mem. Torrey Club 3(3):66, 1893. Type: OL Orur . Ue. 7 o: Capi Perezia laurifolia - Kuntze, Rev. Gen. 3(2):166. 1898. Type: BOLIVIA Cochabamba: Pass hapion Cochabamba and Rio Juntas, 4000 m, 13/2- IV-1892, Kuntze s Small delicate sasika ae 12-38 cm tall with a creeping underground thizome. Stem glabrous, or, in some ze ee se glandularly pubescent with r Ss —) — me) 5 gs a 5 a" io] o Vk pe) © ma = ° = 77) 2 =] n & §. = 2 o = cm long, composed of 4-8 rows of bracts. Outer hracts ovate to een acute, entire, 2-5 mm wide, 4-17 m m long, glabrous or with a few glandular hairs, stiff, shiny, broadly ohstoane along the edges, dark green in the center, ye a red streaks. Inner bracts lanceolate, acute, entire, 1-4 mm mm T 8 . =| ga Bg Pe gg — 3 i Q ® — > oO ie) ie] 5 or ie) a i¢ j=} — feb) 2 Le 9 ° E eg = KS & capitula. Immature ovary from 1-3 cm in len ngth, bearing a few scan strigose hairs, or in some cases some glandular hairs. Receptacle abieks or in some populations with sparse tufts of white or blon Distribution: from northern Bolivia south in the eastern and central Andes to northern Argentina in the province of ts ig 22-2). Altitudinal a from 2500-4500 m. Flowers from Jan May. Representative specimens: Bortvia. La Paz: AP Bast vicinity of La Paz, 4500 m, III, Mandon 24 (NY, P). Cochabamba: Coch abamba, 12000 ft, C A : B G). Tarija: erie a 3400 m, III, Fiebrig 2817 (GH, P), 23-11-1924, F iebrig 2903 (F, GH). arceNTiNA. Jujuy: entre Santa Ana y Caspala, I-III-1940, pone dr co. 11791 (SI); Tumbaya, Volcan, File del Vallecito subido al Cerro Hor 2, 3500 m, i Cabrera & Poe 6 (GH, Castillon 201 (LIL In the Andes of Bolivia and northwestern Argentina is a little known species of Perezia which was apparently described inde- pendently by Rusby in New York and Kuntze in Berlin. Even now collections of P. mandonii are scarce, and the exact distribu- THE SYSTEMATICS AND EVOLUTION OF PEREZIA 103 tion and morphological variation of the species are hard to assess. The specimens from which Kuntze described Perezia laurifolia have broader leaves than those from which Rusby described P. mandonii a few years earlier. Also, Kuntze’s specimens have nodding heads while those of Rusby are upright. However, on all other morphological evidence, the plants of the two collections seem to be conspecific. I have also tentatively included in this species a series of speci- mens from northern Argentina (Volcdén, Jujuy), although the stem leaves of these specimens are much longer than in any others of Perezia mandonii I have seen. At present, the only collections available for comparison are from La Paz (northern Bolivia ), Cochabamba (central Bolivia), and southern Bolivia. Future collections from the intervening areas will show whether there are transitions from one series of populations to another, and whether the three groups of populations do, in fact, consti- tute a single species. Of the species that grow in the same areas, Perezia ciliosa is most similar morphologically to P. mandonii. However, the two can usually be distinguished on the basis of the basal leaves. Those of P. mandonii have smooth margins with a few short white spines. The basal leaves of P. ciliosa are ciliate or dentate. Perezia pun- gens is the only other species of the altiplano region to which P. mandonii is similar. However, P. mandonii is a shiny, glabrous species whereas plants of P. pungens are frequently very pubes- cent. The outer bracts of P. mandonii also make a characteristic pattern of green and white due to the overlapping of bright green bracts sharply edged with white. A species strikingly reminiscent of Perezia mandonii, P. lactu- coides subsp. palustris, is found in southern Chile. There has been little confusion between the two taxa because of the large geo- graphical separation (Fig. 22-2 and 24-1) and their widely divergent habitats. Perezia lactucoides grows in marshes and even standing water whereas P. mandonii is a high puna grassland species. Morphologically, the achenes of P. mandonii are sparsely strigose or have dense glandular trichomes and those of P. lactu- coides are covered with double hairs. It is impossible to tell whether similarities in morphology between P. mandonii and P. lactucoides are the result of convergence or whether they reflect some ancestral relationship. At present, it seems that P. 104 BERYL SIMPSON VUILLEUMIER mandonii is related to P. ciliosa in the P. pungens species group and that P. lactucoides is better placed in the P. magellanica species group. 11. Perezza citiosa ( Phil.) Reiche oe — a Anal. Mus. Nac. Chile 8:35, 1891. Type: c Tarapac o de Copacoya, 3500 m, 18-II-1885, F. Philippi 2950 (SGO, I ness LP). Perezia — (Phil.) Reiche, Anal. Univ. Chile 116:426. 1905. Fl. Chile 4:444, 1905 Perezia ciliosa (Phil. ) ge var. dentata Cabrera, Rev. Invest. Agr. Buenos Aires 11:409. 1957. ARG ee Jujuy: Humahuaca, Mina guilar 0 m, 13-I-1948, on. thts (LP Perezia abbiati Cabrera, Darwini 9:52. . 5 AC. 1949. Typ ARGENTINA. Salta. Poma, Abra del Gallo, 4650 oh 10-II-1946, Cabrera 9059 (LP). Small ai sae with a long thick underground rhizome; plants 3-17 cm tall. Stem terete in cross section, glabrous or with a few glandular tri- chomes ae the capitulum, sometimes slightly striated and reddish in olor, Stem leaves 2-11, small and frequently scale-like, lanceolate, acute, ciliate, glabrous. Basal leaves Be or lanceolate, acute, densely and evenly ciliate along the margin (dentat northern rn Argentina), petioled for almost ne-half the length of the leaf; hs puedane flared and membranous; leaves mm wide, 2-10 cm long, rugose when dry, glabrous. Flowering stems monocephalous, up to 7 flowering stalks per rosette. Individual capitula cam- panulate, 12-30 mm wide, 10-30 mm an upright. Involucre turbinate with a rounded base, 9-20 mm wide, 8-21 m m long; composed of 4-6 rows of bracts. Outer bracts ovate, acute, entire or ciliate, 1-3 mm wide, 3-9 mm long, glabrous, up to one-half scarious, frequently reddish along the edges. Inner bracts lanceolate, acute, entire, 1-3 mm wide, 7-20 mm long, glabrous, one-half to almost entirely scarious, often reddish along the margins. Pappus setose, blond-brown, 6-13 mm long. Florets wr ro per capi co ba 25 mm long with ligules 2-7 mm long; from r cap mma- ture achenes 1-4 mm long, covered with long a date ay een in some populations where they are only slightly pubescent. Mature achenes mm long. Desa with tufts of blond hairs around the point of achene attac romosome ue: Jujuy, i. gran I2n—24. (Fig. Distribution: from southern Pert requipa) south along the Andes altitudes from 3500 m to snow a through Bolivia and south into Argentina to —— 27°S (Fig. ale owering from F pr epresentative specimens oo Arequipa: Volcan El Misti, 15000 ft, LT, Stafford 578 (K). Borivia. La Paz, Vilco, II, Brooke s.n. (BM). Potosi: 91-11-1958, Fabris & rd ait 1745; Tile cara, above San Coaviitie 14000 ft, 2-11-1939, Balls B6005 (F); Humahuaca, Cerro La Soledad, 3500 m, THE SYSTEMATICS AND EVOLUTION OF PEREZIA 105 21-III-1929, Venturi 8631 (GH, LIL, SI, US); Susques, Cerro Tuzgle, 4800 m, 10-II-1946, Cabrera 9097 (LP). Salta: Alta Chorrillos, 4560 m, 27-I-1949, Cabrera & Schwabe 124 (LP). Catamarca: Santa Maria, Campo Colorado, 4400 m, 3-II-1925, Venturi 6240 (US). Tucuman: Calchaquies, 15-II-1915, Castillon s.n. (LIL), altiplano entre Las Lagunas y Cerro Negrito, 4200 m, 28-I-1952, Sparre 9368 (LIL). CHILE. Tarapaca: Tara- paca, Cordillera Cerro Columtusca, Apacheta, 4600 m, III, Werdermann 1109 (F, GH, LIL, LP, NY, SI, US); camino de Putre a Chucuyo, 4100 m, 12— II-1964, Marticorena, Matthei, Quezada 185 (CONC); camino de Huara a Cancosa, 3850 m, 17-II-1964, Marticorena, Matthei, Quezada 312 (CONC); camino de Arica al Portezuelo de Chapiquina, 4000 m, 29-III-1961, Ricardi, Marticorena ¢& Matthei 332 (CONC). Perezia ciliosa grows at very high elevations, practically at snow line. Individuals are usually hidden under clumps of long, stiff grass such as Stipa ichu, or nestled in wet, short grass which makes plants inconspicuous even though they are common. Despite its wide distribution (Fig. 92-4), Perezia ciliosa shows little morphological variation. Within one collection from Tara- paca, Chile (Werdermann 1109) there is enough variation to in- include specimens similar to the type, to plants from La Rioja described as P. abbiatii by Cabrera, and to a small form found in northern Argentina and southern Bolivia ( recognized as P. ciliosa var. dentata by Cabrera). The wide spectrum of variation present in this Chilean collection provides evidence that all of the other populations belong in the same species. There is slight clinal morphological variation discernible across the range when each population, as a whole, is compared with neighboring populations. Plants from northern Bolivia and northern Chile have broad leaves with dense, even cilia, and broad, ciliate outer bracts. The La Rioja, Argentina populations are quite similar to those of Chile, but have a larger mean average head size. Presumably, it was this slight shift in size which prompted Cabrera to describe these populations (Abra del Gallo, La Rioja) as a species, P. abbiatii. A statistical comparison of the mean head size from populations in La Rioja and Tarapaca showed no significant dif- ference (10 per cent chance that ¢ would exceed the value obtained for head width, and a 70 per cent chance t would exceed the value for head length). This type of comparison should not be interpreted rigidly as a criterion for retaining or submerging taxa, but in this case, all of the other morphological characters of the sets of populations are practically identical. es In Jujuy, northern Argentina, and in adjacent southern Bolivia, 106 BERYL SIMPSON VUILLEUMIER plants of Perezia ciliosa are much more delicate in appearance than elsewhere. They have more narrow leaves which are fre- quently dentate, and almost entire outer bracts. Since the species does not apparently occur in central Bolivia, the northern and southern Bolivian populations represent the extremes in an almost circular type of clinal variation from northern Bolivia west to northern Chile, southeast to La Rioja and northeast to southern Bolivia (Fig. 22-4). A similar kind of variation, although more pronounced, occurs in P. purpurata. A reasonable postulate to account for the absence of both these species in southwestern Bolivia is the presence there of wide expanses of salt deserts. In most cases, Perezia ciliosa can be distinguished easily from morphologically similar species, but it has been confused with three other taxa. In Tarapaca, Chile, large plants have been mis- identified as P. purpurata. The most notable difference between the two species in this area of sympatry is that P. ciliosa has entire leaves with dense, even cilia and P. purpurata has dentate leaves that are slightly spiny. In southern Bolivia, some specimens of Perezia ciliosa are similar to P. mandonii (it is possible that P. mandonii may prove to be conspecific with P. ciliosa or, at least to be very closely related to it). The most useful morphological character for dis- tinguishing the two species is the leaf margins: those of P. ciliosa have cilia whereas those of P. mandonii have, at most, a few spines. The other species to which Perezia ciliosa is similar, in general aspect, is P. coerulescens because some specimens of the latter have entire leaves with densely ciliated margins. However, the outer bracts of the entired-leaved plants of P. coerulescens are quite scarious and ovate in outline. The outer bracts of P. ciliosa are non-scarious, green, and very ciliate except in the northern Argentine populations, where the bracts are stiff and lanceolate. 12, PEREZIA PURPURATA Wedd. Perezia purpurata Weddell, Chloris Andina 1:43. 1855. Type: BOLIVIA. Potosi: au voisinage des lagunes, d’Orbigny 1420 (P). rionea atacamensis Philippi, Anal. Mus. Nac. Chile 8:35, 1891. Type: CHILE. Tarapaca: Copacoya, 18-II-1885, F. Philippi 22. ; Perezia atacamensis (Phil.) Reiche, Anal. Univ. Chile 116:425. 1905. FI. Chile 4:443. 1905. Perezia hunzikeri Cabrera, Bol. Soc. Argent. Bot. 3:161. Fig. 1. 1950. THE SYSTEMATICS AND EVOLUTION OF PEREZIA 107 Type: ARGENTINA. La Rioja: General ee El Zanjon, 4000 m, 6-II- 1949. Kraprovickas & Hunziker 5823 (BAB). Perezia keshua Cabrera, Darwiniana 9:59. Fig. 6. 1949. Type: ARGENTINA. Pajuy: ieee Quebrada proxima a Susques, 3700 m, 14-II-1945, Cabrera oce ae alous, or in some populations with a panicle of 2-5 heads; several leet stalks — present via rosette. Individual capitula campanulate, 2-5 cm wide, 3-3. ers ee or slightly nodding. Involucres hemis- pherical to turbinate “47 wide and 1.5-3.5 cm long; composed o rows hen: ee ts. Outer racer ae to oblanceolate, pecan: spiny on the edge mm wide, 7-23 mm long, covered in most populations with a Seas ee e long glandular Lagnuraqts — along the margins in some stoma frequently reddish in the er. sonia bracts lanceolate, and padres oie d into pair as far so 23). Altitudinally from oe m. Blooming from Janos to et Representative specimens: BO . Potosi P : La 4900 m, 3—II-1968, Vuilleumier 492 (GH). ARGENTINA. Jujuy: Yavi, Cerro Negro, 4000 m, 25-II-1940, Meyer 22338 (LIL), faldeo a ‘Cerro Popo- sayo, 4400-4500 m, 1-II-1953, Sleumer 3680 (LIL); Tres Cruces, Puente a, a Aguilar, arriba de | a, m, —1952, Petersen & Pittjerling 153 (LIL) —o 3000 m, 10-II-1927, Venturi 6341 (US); 1-1929, Venturi 9296 3-II-1929, Venturi 9455 (US); awe Blanca, Portezuelo de Sipin, 3700 m, 20-II-1932, Kerail s.n. (LP); Casapalca, cumbres, 1 Tronchac s.n. (SI); Volcan, Abra del Paraguay, 1 J— (LIL). Salta: Caldera, subida al Nevado del Castillo entre ‘Tres Lagun las Cuevas, 4200 m, 16-III-1952, Sleumer & Vervoorst 3008 (US); ge 108 BERYL SIMPSON VUILLEUMIER de] Cajén, 4800 m, 18-II-1914, Rodriguez 1376 (SI). Catamarca: Tino- gasta, San Francisco, 4200 m, 31-I-1930, Schreiter 6091 (LIL), Tres Que- bradas, 4150 m, 27-III-1951, Vervoorst 3223 (LIL, P); Belén, Loma O s.n, 4000 m, 30-I-1933, Jorgensen 1832 (SI); Valle del Cajon, 4100 m, 22-I- 1914, Rodriguez 1376 (A, LIL); Antofagasta de la Sierra, Incahuasi, 4200 m, 1-IV-1950, Hueck 510 (LIL). Tucuman: Tafi, Cerro Calchaquies, 1-I- 1915, Castillon s.n. (A, LIL), La Puerta, 4000 m, 30-I-1933, Burkart 5184 (LP, SI); Cerro de la Mina, 3800 m, 14-IV-1924, Venturi 6331 (US); Rio US ioj Managua, 2800 m, 28-IV-1926, Venturi 6906 ioja: General madrid, entre Rio Las Cuevas y Portillo del Alto, cercanias del Leoncito, 25-I-1949, Kraprovickas & Hunziker 559 , cercanias Cerro ete, 4500 m, III, Hunziker & Caso ea i Cordillera el Zany6n, 3700 m, 14-I-1926, Johnston 6187 (GH, US); Quebrada del Salto, 16-I- 1930, Perez Moreau 216 (LP). cumLe. Tarapacd: Arica, entre Portezuelo de Chapiquina y Putre, 4000 m, 27-III-1961, Ricardi, Marticorena ¢ Matthei 220 (CONC). Atacama: Quebrada de Pastos Largos, 4000 m, 26—-I-1958, Behn s.n. (CONC); Copiapé, Cordillera Rio Figuerén, Cerro Paredones, 3500 m, I-1926, Werdermann 977 (F, GH, HBG, LIL, NY, SI, US); Val- lenar, Cordillera Laguna Chica, 4000 m, I-1924, Werdermann 265 (F, GH, HBG, US), vicinity Lago Valeriano, 4000 m, 8-10-I-1926, Johnston 6075 (GH, US); Camino al Salar de Maricunga, 4000 m, 31-I-1963, Ricardi, Marticorena & Matthei 594 (CONC). The species treated here as Perezia purpurata is a confusing one because it is variable morphologically, disjunct geographically (Fig. 23), and there has been misapplication of the names for several isolates. The species essentially consists of four series of populations isolated in different mountain ranges. The first is a series of populations in northern Chile and western Bolivia; the second centers in La Rioja, Argentina; a third, small group is found in the Sierra de Calchaquies (Salta and Tucuman, Argen- tina); and the fourth is located in Jujuy, northern Argentina. The confused nomenclature of these various populations should also be discussed briefly. The oldest available name is Perezia purpurata, a name given by Weddell to a specimen from Potosi, Bolivia. This name fell into disuse subsequent to its publication— probably because the type specimen was in poor condition and the species was not collected again in Bolivia. Later authors presumably felt that a plant collected once in central Bolivia could not be the same species as the later described P. ataca- mensis Phil., a Chilean taxon known from abundant material. In February, 1968, I revisted the high puna above Potosi and found plants undoubtedly of the same species as Weddell’s from THE SYSTEMATICS AND EVOLUTION OF PEREZIA 109 7 aeestcs = RRA DE | < + PURPURAT \ AIACAMENSIS HUNZIRERI) SIE A es : Me URFURATA™ oy ATACAMA, | LA RIOJA CALCHAQUIES, \ ARGENTINA ° a CHILE ARGENTINA n as HEIGHT OF PLANT “p] 5 H Woe oor i i ‘y F Yt Saat ay t eee Oy KESHUA', e IN \. eR i i } " " 4 \ WIDTH OF LEAF "ATACAMENSIS" = (Q)> ial ke bee Ps a rp AE * SIERRA CALCHAQUIES " ar 01 ba ty ae a: Pb aoc Fe f i “HUNZIKERI I" \ 7 ui ENGTH OF L LEAF ays INVOLUCR E + J . ; i] Cr LENGTH OF | WIDTH OF w | Fic. 23. Distribution of Perezia purpurata showing the localities of the four major disjunct groups of populations, and Dice-Leraas diagram of individuals from each of the four areas to show the overlap present in morphological characters (measurements in cm). this locality. Although plants were very rare (due to sheep graz- ing), I was able to collect enough material to establish that they were conspecific with plants from Chile. It is still not known whether the apparent disjunction between Tarapaca, Chile and Potosi, Bolivia actually reflects a range disjunction or merely poor collections from the intervening area. Many years after the description of Perezia purpurata (and P. atacamensis ), Cabrera circumscribed a new species, P. hunzi- keri from La Rioja, Argentina. Plants from these populations are somewhat smaller than those from Atacama, but the amount of overlap in the dimensions of various parts (organ size is supposed to separate the species) is large (Fig. 23). Since the two sets of populations are practically indistinguishable in all other charac- ters, they are considered here to belong to the same specific taxon. When he circumscribed Perezia hunzikeri, Cabrera described another species, P. keshua, from northern Jujuy (Argentina ). These plants are distinguishable from those of Chile and La Rioja because they have polycephalous flowering stems and small capitula. It is worthy of note, however, that there is at least one specimen of P. purpurata from Atacama, Chile (Werdermann 265) 110 BERYL SIMPSON VUILLEUMIER which has a bicephalous flowering stem. The existence of this spe- cimen suggests that the character of polycephalous stems is not sufficient in itself to warrant specific rank. Rather, the populations in northeastern Jujuy seem to be a segment of P. purpurata which was isolated in the mountains of this area and has undergone some morphological divergence. Almost a hundred years after its publication, Cabrera reapplied Weddell’s name, Perezia purpurata, to a series of populations in the Sierra de Calchaquies (Salta and Tucuman, Argentina ). Plants from this area are the most distinctive of any considered here to belong in P. purpurata and I consider their inclusion ten- tative pending further study. A factor which has reinforced the decision to include the Calchaquies populations in this species is the presence of intermediate specimens where plants from this area come into contact with those from northeastern Argentina (the former P. keshua populations). Examination of the pollen from intermediates shows that they are male fertile. This zone, without apparent sterility of hybrid plants, indicates that it is an area of secondary contact of imperfectly isolated forms of one biological taxon. It is suggested here that the present pattern of variation of Perezia purpurata is the result of Pleistocene events. A lowering of the snow line during glacial maxima would have allowed the species to occupy, and migrate across, areas now separating the populations. As the ice retreated, populations would have been left stranded on high mountain ranges surrounded by areas of unfavorable habitat. Once isolated, selection by local conditions would have produced some morphological differentiation. Both morphological and chemical evidence indicate that Perezia purpurata is related to P. pungens and P. coerulescens. Confusing specimens of P. pungens can be distinguished from those of P. purpurata because the heads of the former are less elongate and its achenes usually have glandular (rather than sericeous ) trichomes. Plants of P. coerulescens are usually much smaller than those of P. purpurata and their basal leaves are less petioled. Moreover, the leaf bases of P. coerulescens are not per- sistent as they are in P. purpurata. 13, Perezia pitirera (D. Don) Hook. & Arm. Clarionia pilifera D. Don, Philos. Mag. 11:388. 1832. Type: ARGENTINA. Mendoza: Andes of Mendoza, El Cerro de la Pulcura, Gillies s.n. (K). THE SYSTEMATICS AND EVOLUTION OF PEREZIA lll Perezia pilifera (D. Don) Hooker & Arnott, Comp. Bot. Mag. 1:34. 1835. Perezia pilifera (D. Don) Hook. & Arn, var. niri uaoensis Hosseus, Trab. Inst. Bot. Farmacol. 33:101. i915. Type: NTINA. Rio Negro: Cerro Utne, lei m, 20-II-1914, Hosseus 498 (no nea lechleri Schultz-Bipontinus, Flora “38: 122, 1855. Type: CHILE. Magallanes Sandy Point, Lechler 1044 (P, Isoty , NY). Homoeanthus humilis Philippi, Anal. Univ. Use 87:307. 1894. Type: CHILE. pansies Valle de Bio Bio, Guayeltué, II-1884, Rahmer s.n. (SGO). Perezia linearis Lessing var. humilis (Phil. ) Reiche, Anal. Univ, Chile 116:428. 1905. Fl. Chile 4:447. Tiny rosette plants 2-13 cm tall with a thick woody rootstock. Stem gla- brous, sometimes reddish in color, bearing 1-4 scale-like, Fg tag acute, f m any given plant: either linear, entire, mucronate, and with long, soft white at intervals er he the edges; 1-5 mm wide, 7-16 mm apie usually Siew but, rarel a few peed glandular trichomes; always wi with dark red . Inner bracts lanceolate, igid, acute to mucronate, entire, 1-4 mm wide, 8-18 mm long, glabro the i r x a ialized tri- chomes (Fig. 3-3). Mature achenes 3-4 mm sate Rett te glabrous or with rings of short trichomes around the ovary pane Distribution xtensive range from San Juan entina to the south- ern part of Tierra del Fuego (Fig. 26-4). ieeatuat am 600-4300 Flowering from March sentative spec Ss: NTINA. San Juan: Dpto. ud Cordil- lera de Colanquil, 1887-1888, ses iar s.n. (CORD). Men pto San Carlos, Laguna Diamante, 3300 m, 4-IlI-1943, Covas 1063 (CH), entre el Paso de Portillo y la Laguna del Diamante, Cord. del Portillo de la Llareta, 4300 m, II-1900, Stegmann 11238 (BAB); alto valle de Camul-cé, 14-II- 1942, Burkart, Troncoso ¢ Nicora s.n. (SI). yak: Rape Parque Nacional Nahuel Huapi, alrededores de ae om Cerro Colora’ m, 5- Diem 1821 (SI), Cerro Catedral, 1 m, 7-II-1965, Pt ier 180, 181 (GH). Chubut: north of Lago F salute 2 27-I11-949, Pederson 312 (US). Santa Cruz: Lago Argentino, Rio Vueltas, arriba de la Est. Pérez, 1200 m, 28—-XII-1950, Sleumer 13/2 (US), Est. Fitzroy, arriba de “Chorro 1200 m, 31-XII-1950, Sleumer 1417 (US). Tierra “pe eee Dpto. Ushuaia, nn. Ushuaia, 11-II-1948, Vervoor- ag Mail- es, , Bridges us (P); Dpto. Petore south of Junta de Piuquenes, Rio Sobrante, 3400 m 2-II-1939, ae 17293 (F, GH) Santiago: Valle del rt Volcan, 2700 m, I1I-1933, Grandjot 1097 Romibage Colchagua: Cajon pig ges Ii-1831, ~ 284 P). Nuble: Termas de 2300 m, 6-11-1936, Pirigallo, Cabrera 3642 (F). M — Lon quimay, Paso Gnu Hachado, "31111-1965, uilleumier 220 (GH). Ma: dear Cerro Guido, Estancia Guido, 750 m, 112 BERYL SIMPSON VUILLEUMIER 16-I-1952, Pfister & Ricardi 463 (CONC, LIL); Ultima Esperanza, Monte Prat, 800 m, I-1950, Magens 80 (CONC); Las Cumbres Baguales, 500- 850 m, 6-II-1962, Ricardi & Matthei 413 (CONC); Cordillera Seforet, 1000 m, I-1931, Donat 435 (GH). This species has the most extensive latitudinal range of any of the Chile-Argentine species of Perezia, occurring continuously from about 28°S to 55°S (Fig. 26-4) where numerous plants crowded together form mats in rocky soil above timberline. The morphological variation of Perezia pilifera is checkerboard rather than clinal. Plants from extremely high populations in Mendoza, Argentina are small and have highly dissected basal leaves. In Tierra del Fuego, plants are frequently elongate and their leaves have widely spaced basal segments. However, plants similar to either of these extremes are randomly scattered through- out other parts of the range. This species exhibits the interesting feature of leaf dimorphism with all of the other characters of the two morphs being identical. The two types of plants are considered polymorphs (in the sense of Mayr, 1963, p- 150-158, 669) because they are “discontinuous phenotypes,” i.e., an individual plant has all one type of leaf. No intermediate plants or leaf shapes have been seen and both morphs can grow side by side in the same population. The more common form has highly dissected leaves with fleshy, lanceolate segments each of which ends with a long, soft, white spine. The other morph has linear, needle-like leaves with no, or only a few, scattered white spines. Unfortunately, no experimental work could be done to clarify the genetic system underlying this poly- morphism. Populations which contain only one of the two morphs are presumed to have been founded by a propagule(s) genetical- ly capable of giving rise to only one type (founder principle of Mayr, 1963 p. 211). The entire leaved morph of P. pilifera, which Phillippi made a variety of P. linearis, superficially resembles species in the P. recurvata group. However, the similarity is only in habit and leaf outline. The leaves of P. pilifera are thick and fleshy, whereas those of P. linearis are soft and flat. The bracts of P. pilifera are also quite distinct from those of either P. linearis or P. recurvata in that they have long, soft, white spines, rather than even cilia or short, rigid spines along the margins. Finally, P. pilifera has a unique type of achenial trichome unlike that common to the members of the P. recurvata group (F ig. 3-3, Table 3). THE SYSTEMATICS AND EVOLUTION OF PEREZIA 113 It is difficult to determine the relationships of Perezia pilifera because it is so distinctive morphologically and its achenial tri- chome type is unique in the section. On the basis of chemical data, supported by some morphological similarity, it has been placed close to the P. pungens and the P. coerulescens groups. 14, PEREZIA CARTHAMOWES (D. Don) Hook. & Arm. Clarionia carthamoides D. Don, Phil. Mag. 11:388. 1832. Type: ARGENTINA. Mendoza: elevated parts of the Andes, Alto de La Laguna, west side of the Cordillera, 1821, Gillies s.n. (K Perezia carthamoides (D. Don) Hooker & Arnott, Comp. Bot. Mag. 1:34. 1835. Perezia diversifolia Meyen, Reise um die Erde 1:311. 1834, Type: De- stroyed at Berlin. (Photo a NY). cute. Colchagua: Cordillera de San Fernando, 7-1831, Meyen s Perezia diversifolia tec var. crispa Meyen, Reise um die Erde 7. 1834. Type: cume. Colchagua: Cordillera de San Fernando, 7-1834, sles s.n. (photo GH Clarionea carthamoides D. Don var. crispa (Meyen) Philippi, Linnaea 33:124. 1864. Clarionea multicapitata Remy in Gay, Fl. Chile 3:410. 1849. Type: CHILE. Cordilleras, 1839, Gay 297 (P, Isotype Perezia multicapitata (Remy in Gay) Weddell, Chloris Andina 1:44. 1855. Clarionea spectabilis Philippi, Anal. Univ. Chile 87:303. 1894. Type: HILE. Coquimbo: Ilapel, El Pifion, 1888, F. Philippi 2237 (SGO, Isotype LP Desert perennial 4-20 cm tall with a long creeping rhizome. Stem terete in cross section, slightly striated, sometimes reddish in color, _ with dense glandular trichomes, es cial near the capitulum. Stem leaves “s 12 up the stem _ up to 1.5 cm wide a ny cm shar sometimes a s but more re with glandular trichomes. Basal leaves variable in number, lanceolate in populations monocephalous, in others wi raceme; up to 17 heads on ’ different flowering stems sometimes present on one plant. Individual ag campanulate, 1.5-4.5 cm — pee cm 1 ispherical, 1.5-3. very scarious mae ibe margins, often r dular tri long, tawny, white, or pink in color. Florets colored; outer florets 6-31 mm long with ligules 5-14 mm long from ote florets per capitulum. Immature achenes 2-6 mm long, s ture of double hairs and glandular trichomes. Mature achenes with ‘none double hairs and prominent, dark amber glandular trichomes; up to 6 mm long. Receptacle convex with a few scattered trichomes on the surface. 114 BERYL SIMPSON VUILLEUMIER Distribution: in Chile from Coquimbo south in the mountains to Col- chagua. In Argentina in the provinces of Mendoza and San Juan (Fig. 27- 1). Altitudinal range from 1800-3600 m. F lowering from November to h arch. Representative specimens: ARGENTINA. San Judn: Cordillera Real, Paso del Concerro, 16-I-1953, Castillanos 15137 (US); Portejuelo La Fria, 3600 m, 1-II-1950, Ruiz 13002 (LIL, LP); Mercedaris, Arroyo Blanco, 1900 m, 29-I-1951, Semper 13938 (LP). Mendoza: between Puente del Inca and a 15-I-1949, Leal 11690 (LIL). cue, Coquimbo: Dept. Ovalle, Rio Gor- dito, 30-I-1951, Jiles sn. (GH): Dept. Illapel, Cerro La Yerba Loca, two hours by horse east of La Vega Escondida, 22—XII-1938, Morrison 16948 (GH). Aconcagua: Caracoles, head of the Aconcagua Valley, I-1936, Jaffuel 3519 (GH). Santiago: ué, Monte Cantillana, 2-I-1939, Barros 2012 (LP, SI); Cajén de Morales, valle de Maipo, 3000 m, 15-III-1921, Jaffuel 417 (GH); Potero Escondido, 3500 m, 11-1947, Boelcke 2463 (LP); Rio Yeso, 17 km de Romeral, 28-XII-1941, Biese 651 (LIL); hills at Maipo, San i 0 m Pennell 12320 ee ); Rancagua, Cordillera de Codegua, 3000 m, 17-I-1945, Barros 3914 (LP). Colchagua: vegas del Flaco, 1900 m, 18-I-1964, Marti- corena & Matthei 718 (CONC), Cajon de las Damas, XII-1936, Milner s.n. (CONC); Cordillera de Tinguiririca, 2100 m, I-1929, Pirian 61 (GH). Perezia carthamoides is one of the more showy plants of the dry areas of northern Chile and northwestern Argentina (Fig. 27-1). It is a fairly common species at high elevations in dry or subhumid soil. In the spring it displays large numbers of showy rose, violet, or cream-colored heads, sometimes with several dif- ferent colors of florets in one population. ost of the morphological variation within Perezia cartha- moides is east-west, rather than north-south. Beginning in the Santiago valley area (south to the Bafios de Flaco in Colchagua) is a series of populations described as Clarionea multicapitata by Remy, which, as the name implies, have an inflorescence of capitula rather than monocephalous flowering stems. Other mor- phological features associated with these populations include foliage that tends to be lighter green than that of other popula- tions, and glandular dots instead of glandular trichomes on the leaf and bract surfaces. THE SYSTEMATICS AND EVOLUTION OF PEREZIA 115 Despite the fact that plants from this western series of popula- tions are easily recognizable, there is evidence to indicate that they are biologically conspecific with more “typical” Perezia car- thamoides. All of the “multicapitata” populations are found west of the Andes. Going east across the high passes (i.e., between Portillo and Puente del Inca), one finds a gradual morphological transition from the central Chile populations, to those found in Mendoza, Argentina. At high elevations in Mendoza, at the eastern range extremity, the populations of Perezia carthamoides (described as P. cartha- moides var. crispa Meyen) are characteristically compact, and have highly lacerated leaves. These morphological features are probably best explained by the fact that these plants grow at altitudes about 3300 m. The transition in morphology eastward from central Chile to Argentina indicates that the populations exchange genetic mate- rial and should be considered one species. The differentiation which has occurred seems to be the result of isolation of popula- tions to the east and west of the Andes during the Pleistocene, when mountain-top glaciers were low enough to effect such a separation (Briiggen, 1950). Once this barrier was removed, the ranges of the eastern and western populations re-expanded and again came into contact. Although the period of isolation was sufficient to allow some morphological divergence, the popula- tions do not seem to have become reproductively incompatible, and now form intermediates when they come into secondary contact. Perezia carthamoides shows some morphological resemblances to P. purpurata and P. poeppigii although it is usually easily distinguishable. It can be distinguished from P. purpurata which has softer, pubescent outer bracts, by its stiff, broadly scarious bracts. The heads of P. purpurata are also elongate rather than broadly hemispherical as in P. carthamoides. Perezia poeppigii is easily recognized by its smaller stature, very lanceolate bracts, and turbinate capitula. Data from chemical analyses suggests that Perezia carthamoides is close, at least in phenolic and flavonoid compounds, to P. poep- pigii and, through it, to the P. recurvata species group (Fig. 11 and 12). In morphology also, there is a gradual transition of some characters from P. carthamoides to P. poeppigii and P. recurvata. 116 BERYL SIMPSON VUILLEUMIER Since P. carthamoides belongs to the P. pungens group, believed to represent a rather ancient assemblage, it could be the modern descendent of the form which gave rise to the P. recurvata group. 15. PEREZIA viscosa Less. Perezia viscosa Lessing, Synop. Comp. 408. 1832. fed CHILE. Bio Bio: Meseta de Antuco, XII, Poeppig 772 (P, Isotypes F, Homoimahes sedan lee ) a i ase er 4 :64, "1838. athu it Pe Trans. Linn. Soc. I. 16:205. 1830. (non Perezia pill eee Philippi) sie CHILE, Ruiz & Pavon (type not seen). Perezia V gdeanees (Lag. ex D. Don) Hooker & Arnott, Comp. Bot. Mag. 1:33, 1835 Tall, robust plants arising from a basal rosette of few leaves; plants 23-64 cm tall. Stems terete, often striated, covered with long (.5 mm m) multicellular glandular trichomes. Stem leaves 2-8 scattered up the en, lanceolate, acute, minutely dentate, clasping, very variable in size; fro cm long to almost scale-like; coriaceous with scattered glandular icine on the surface. Basal leaves lanceolate to spathulate, per: sin ntire, lobate to dentate, attenuate at the base; 1-32 cm wide, m long; frequently glabrous, but sometimes with scattered heoctulae peeve Inflorescence in most cases a loose raceme of 2—4 heads; some plants monocephalous. Capi- tula campanulate, 2.7-4.3 cm wide, 1.7-2.1 cm long; upright or slightly nodding. Involucre hemispherical to papi composed of 4-6 rows of bracts; 1.2-3 cm wide, 1-2.6 cm long. Outer bracts ovate to lanceolate, acute to obtuse, slightly dentate; 1-4 mm cade 4-11 m mm long; usually non- end, of the ligule; about 35-46 florets per capitulum. Immature ovaries covered with dense, aude = or copper-colored trichomes mixed with glandular trichomes; ong. Mature achenes 4 mm long with a few scattered double hairs ery pliers trichomes. pre ae with short tufts of white trichomes around the point of achene attachm Distribution: oo rere in Chile south in the Not hofagus forest to Osorno. In Argen in Neuquén, also in the Valdivian forest zone (Fi 24-2), Pera, ate pina from 100-1200 m. Flowering December through Mar Re epresentative specimens: ARGENTINA, Neuquén: Parque oe Nahuel uapi, Cerr pace Portejuelo de los Ardillas, 1200 m, Diem 27 (LP), 770 m, 144 1934, peas 673 (NY); Mamuil Malal, 11931, Joseph 5569 (US). cue. Colchagua: Rancagua, Bertero 702 (GH). Bio Bio: 18—I-195. Llaima, I-1925, Joseph 3141 (U S). Valdivia: Chodhuenco, 8-1-1934, Mon- tero 1034 (GH); Cordillera de Ranco, XII-1856, Lechler 233a iP}; THE SYSTEMATICS AND EVOLUTION OF PEREZIA 117 Punahué, 100 m, 15—-XII-1938, Hollenmayer 792 (LP); Hualhuapi, 19-V- 1875, Reed 16 (NY). Osorno: Los Halros, I-1835, Gay 360 (P). Like Perezia pedicularidifolia, P. prenanthoides, and P. lactu- coides (subsp. palustris), P. viscosa is not actually a high Andean species. Its range lies entirely within the Nothofagus forest belt below timberline (Fig. 24-2). The distributional boundaries of all of these species are those of the usual Valdivian forest inhab- itants. Morphologically, some plants of Perezia viscosa are hardly distinguishable from P. lactucoides subsp. palustris, and yet other specimens are much more similar to plants of P. pedicularidifolia. However, in the Nahuel Huapi (Argentina) area, the three species are sympatric and seem to retain their specific identities. In Chile, the three are more similar morphologically and some hybridization between any two or all three has possibly occurred in the province of Valdivia as Reiche (1905) has previously sug- gested. In general, Perezia viscosa is very pubescent on the flowering stems and outer bracts whereas P. lactucoides subsp. palustris has only a few scattered trichomes. The corollas of P. viscosa seem always to have some glandular trichomes on the under side of the ligule and in a small tuft at the end of the ligule. These tri- chomes can best be seen on the top of an unopened floret. I have never observed these hairs on specimens of P. lactucoides subsp. palustris. The other most conspicuous difference between the two species is the base of the leaf: in P. viscosa, it is attenuate and in P. lactucoides subsp. palustris there is a distinct petiole about one-half the length of the leaf. The other species to which Perezia viscosa is similar is P. pedicularidifolia (especially the Valdivian populations ). Perezia pedicularidifolia is, however, always monochephalous whereas P. viscosa frequently has two or more heads per flowering stem. The basal leaves of P. viscosa tend to be slightly spathulate as opposed to the lyrate leaves of P. pedicularidifolia. The corollas of the florets of P. pedicularidifolia are also glabrous rather than glandularly pubescent on the ligule. 16. Perezia Lacrucowes (Vahl) Less. cm tall. Stems arising from a Plants extremely variable in : with a few scattered trichomes, size, 8-69 rosette of few leaves, terete, glabrous or 118 BERYL SIMPSON VUILLEUMIER P PEDICULARIDIFOLIA = > v age - ie AUP . a | Ses oP NUTANS WP BELLIDIFOLIA FOLIA bee PRENANTHOIDES xP MEGALANTHASe? = | ne “ Pre..°25; Distributions of six members of the Perezia magellanica species group: P. sages an ma: 6 eae ou —— P; belie and P. megalantha. Fic. 25-4 of P: and P. pre cides, the only two species of the P. paiamaikccai species group. ent also Fic. oe 134 BERYL SIMPSON VUILLEUMIER capitula born singly on each peduncle; up to 6 flowering stems per rosette. cm wide, 1.9-4.5 cm long, upright. Involucre broadly hemispherical, 2.2-2.8 cm wide, 1.5-1.9 cm long; composed of 4-6 rows of bracts. Outer bracts ovate to spathulate, obtuse to acute or even mucronate, undulate or slightly dentate, broadly scarious along the margins, epresentative specimens: AR Comber 872 (K); Sierra Mamuil Malal, Comber 1098 (K). Rio Negro: Parque Nacional Nahuel Huapi, Cerro Catedral, 1800 m, 7- leumier 183 (GH), Cerro Gutierrez, 1400 m, 25-II-1905, Buchtein 66 (US); tro Meseta cerca del Lago Traful, 1900 m, Hosseus 1225 (CORD). One of the prettiest species growing above timberline in the Lake Region of Argentina and Chile is Perezia bellidifolia. It usually grows close to snow line in gravel and sand, protected by surrounding rocks (Fig. 25-3) but has been reported once within a forest of Nothofagus pumilio. The distributional range of P. bellidifolia is very restricted, and only a few collections of the species have been made. Consequently, it shows little geograph- ical variation. Perezia bellidifolia seems to be related to P. lyrata and P. megalantha, both of which also have small rosette habits with espinescent leaves and monocephalous flowering stems bearing only one or two leaves, and broad outer bracts. The wide scarious margins of the outer bracts and the shiny glabrous leaves of P. bellidifolia easily distinguish it from either of the two related species. The broadly hemispherical capitula of Perezia bellidifolia and its scariously margined bracts are somewhat reminiscent of P. cartha- moides, a species of northern Chile and northwestern Argentina. The report by Hosseus (1915) of a sepcies in Nahuel Huapi (Rio Negro, Argentina) of Perezia “aff. carthamoides” refers, I believe, to P. bellidifolia. Hosseus listed the habitat as dry, rocky soil on the mountain peaks at elevations of 1900-2000 m. The only species at all similar to P. carthamoides in such localities is P. bellidifolia. THE SYSTEMATICS AND EVOLUTION OF PEREZIA 135 Yet the two are quite distinct morphologically, and probably not related at all. They can be distinguished at a glance because P. carthamoides has spiny foliage whereas that of P. bellidifolia is entire and smooth. 24, PEREZIA MEGALANTHA Speg. Perezia megalantha Spegazinni, Rev. Fac. Agron. Vet 3 (30-31):540. 1897, Type: ARGENTINA. Santa Cruz: Lago Argentino, 1884, Spegazinni 1890 (LP). Perezia oleracea O. Kuntze, Rev. Gen. Plant. 3(2):167. 1898. Type: j N ARGENTINA. Patagonia, 1882/4, F. P. Moreno & Tonini s.n. ~_ broadly ovate, acute, dentate, and covered with glandular trichomes. Basal leaves spathulate, obtuse, lobed or dentate, narrowing at the base; 1.1-2.6 cm wide, 3-7 cm long; surface with glandular trichomes. Heads one per flowering stem, up to three per rosette, campanulate in outline, 2-5 cm wi 2-5 cm long; upright to slightly nodding. Involucres broadly hemspherical, 1.8-3.2 cm wide and 2-3.5 cm long; composed of 4-6 rows of bracts. Outer bracts deltoid, orbicular, or broadly ovate, acute, dentate; 5-18 mm wide, 4 mm long; so covered with glandular trichomes that they stick together. Inner bracts spathulate to lanceolate, acute to acuminate, entire, almost 8 i : i Argentina border at the southern parts of Santa Cruz in Argentina, and Magallanes in Chile (Fig. 25-3). Flowering December to F ebruary Representative specimens: ARGENTINA. Santa Cruz: ; Cordillera Cristales, 2700 ft, 29-XII-1958, James "3442 (LP); Estancia Stag River, 3500 ft, 26—XII-1957, Tweedie 213 (K, LP). CHILE. Magallanes: Estancia Guido, 700-900 m, 10-I-1952, Pfister & Ricardi 12157 (CONC); Dpto. Ultimo Esperanza, Las Cumbres, Baguales, 500-850 m, 6—II-1962, Ricardi ¢+ Matthei 390 (CONC); Cordillera Paine, 1200 m, I-1931, Donat 402 (GH, LIL, SI). Perezia megalantha appears to be a very localized species, found growing in rock crevices in a small area of southern Chile and Argentina only (Fig. 25-3). Recently, Thomasson (1959, Pp: 28) reported the species growing near Bariloche along rapid streams in the Valdivian forest. His report would extend the range of the species northward by almost 800 km. I have seen no speci- men from this or any area between the southernmost part of the : f> ° 8 : 8 136 BERYL SIMPSON VUILLEUMIER continent and Bariloche. Cabrera (1939) did not mention this species in his treatment of the Compositae of the Nahuel Huapi National Park. It seems likely to me that a mistake was made in identification and that Thomasson actually collected P. lyrata or P. bellidifolia, both of which do grow in the national park area. This species is one of the most unique of Perezia in South America, instantly recognized once it has been seen. There is no other species in the genus with such enormous heads, large bracts, and dense covering of very long glandular trichomes. Plants have been described as “sticky” in fresh condition, and in dry speci- mens it is impossible to separate the bracts without tearing them because they are matted by interlocking trichomes. Perezia lyrata also has large heads and bracts which almost equal those of P. megalantha in size. Yet the bracts of P. lyrata are coriaceous (in the plants from large-headed populations) and are not covered with the same type of trichomes. Perezia lyrata may possibly be the modern species most closely related to P. megalantha. 25. PEREZIA COERULESCENS Wedd. Perezia coerulescens Weddell, Chloris Andina 1:39. Plate 10 A. 1855. Type: Peru. Cuzco: X-1839-II-1840, Gay s.n. (P). Perezia coerulescens Wedd. var. amplibracteata Tovar, Pub. Mus. Hist. Nat. Lima Bot. 8:16, 1955. Type: ansiri, 44) 500 . Perezia nivalis Wedd. Chloris Andina 1:39. 1855. non Homoianthus nivalis Philippi. Type: PErv. Carabaya, III-VII-1847, Weddell 1848 (P). Perezia integrifolia Wedd. Chloris Andina 1:40. 1855. Type: BOLIVIA. Cochabamba: summit of the Cordillera of Motochata, d’Orbigny 488 (P). Perezia cirsiifolia Wedd. Chloris Andina 1:41. 1855. Type: Boxivia. Lare- caja, Cordillera de Sorata, 5100 m, 1851, Weddell s.n. (PF). Perezia violacea Wedd. Chloris Andina 1:42. 1855. Type: BOLIVIA. Potosi: Quebrada de las Lagunas, III, @Orbigny 1417 (P). Perezia nitidifolia Koster, Blumea 5:677. F ig. 5w-z. 1945. Type: BOLIvis. Paz: moorland meadows of the plateau of Palca, 3600 m, V-1911, ype . » Darwiniana 9:55. Figs. H-J. 1949. Type: ARGENTINA. Jujuy: high mountains of Santa Ana, 3500 m, 1-III-1940, Burkart & Troncoso s.n. (SI). Small rosette plants appressed to the ground, 1-9 cm tall. Roots long and rhizomatous. Flowering stems monoce halous, usually inconspicuous but occasionally rising above the rosette, bearin clasping, lanceolate stem leaves; sometimes reddish color. Basal leaves several, conferted or in a loose rosette, lyrate to oblanceolate in outline, acute btuse, lacerate with spiny segments to undulate; base attenuate, broa , membranous; width 6-26 mm, 11 cm; surface usually glabrous, but occasionally with a few scattered glandular trichomes. Capitula campanulate, 1.2-4 cm wide, THE SYSTEMATICS AND EVOLUTION OF PEREZIA 137 1.2-3.5 cm long, upright. Involucre narrowl ee 9-30 mm wide, 1.2-2.7 cm long; composed of 4-8 rows of bracts. Outer bracts oblong to ovate, mucronate to acute, dentate and spiny a sgh scarious (often broadly so) along the margins; often reddish in color a with scattered long, scarious, glabrous, pappus brown, 1.1-2.3 cm long. Florets white, yel- 3¢ Ow, orange, scarlet, maroon, violet or blue; outer florets 1.7-3.3 cm long with ligules 4-12 mm long; from 11—40 florets per capitulum pee usually with some strigose trichomes at the Kg and scattered aoe Argentina at elevations ‘of 3000-59 00 m (Fig. 26-1). Somat occurs from to 2-1 Representative specimens: PERU. Huanuco: 35 mi west of Huallanca, Yanshallas. 16000 ft, 2~-X—1922, Macbride é Featherstone 2481 (F, GH, US). Lima: Valley Rimac, 4900 m, 22-II-1954. Raube & Hirsch P313 hes near Antaicocha, Cerro Colorado 98 of Canta, 3900-4 VI eae 14661 (F, GH, NY, ). Junin: near Morococha, Ses an m, 1-V-1942, Grant 7562 (F), eae alca, 15500 ft, V, Macbride & Feather- stone 843 (F, GH, US); vicinity of La Oroya, 1918, Kalenborn ¢> Kalenborn 178 (GH, NY, US). Huancavelica: Huancav elica, Huaytanayoc-Tansiri cerca a Manta, 4400-4500 m, 2-IV-1953, Tovar 1186 (GH); Castrovirreina, Choclococha, 4600-4700 m, 4-V-1958, Tovar 2888 (GH). Ayacucho: Can- gallo, Tojto, 4000 m, Velarde 5259 (LP). Cuzco: Ollantaytambo, 3000 m, 1 —196 Diaz 2025 (LP); Cordillera del Pachatusan, 4400 m, VI-1929, Herrera 2573 F); Azuangate, 5700 m. 10-V-1954, Raube & Hirsch P1136 abe Fey. 1937, Stafford 808 (F). Puno: Juro Juro, San Gahan 13000 ft, VI, Fisher 33 (BM); Santa Lucia, 14500 ft, 11 ar ” Stafford 706 (F, K). Crucero Alto, 14700 ft, IV, Stafford 657 (BM); Azangaro, Salcedo, Mt. pean 16— XI-1938, Vargas 9626 (F, K). spoxrvia. La Fox: Chacaltaya, I 1908, Buchtien 1588 (US); highlands at _ Titicaca, Vato Buchtien 6803 weet, vicinity of Sorata near sh gts ta de Chacah, 0 m, IV, F, GH, NY, P, US); gs the psi of the Tilt Anan Sorata ne down to Sorata, 16000 ft, 1926, Tate 822 (NY); Larecaja vicin- ity of Coroico, Sancha m, — a2-(F, XI-1890, Bang 915 (F, GH, NY, US); e at the head of the Challana Valley, s bana 15000 ft, 36-1V-1950, Brooke 6317 oe F, NY); Paso ruces road from Cacsata od Quime, 16000 ft, 11-IV- sit Brooke potty (BM). Oruro: near Araca, mine 1 100 mi from Viloco via Eucalyptus and Cacsata, 14000 ft, IIT, on 5529 (BM). sero sas Chapare, km 75, road between Cochabamba and Tunari, 4000 m, 19-I-1958, Plateau, 1891, Bang 1217 (GH, NY, US). arncentina. Jujuy: Santa Ana, m, 1—-I1J-1940, Burkart & Troncoso 11795 (LP, SI); Humahuaca, Tres Cruces, 3400 m, I-1925, Venturi 10234 (GH). Salta: Oran, Cerr o La Esco- lera, 3800 m, 23-IV-1945, Pierotti 1348 (LIL); Valle de Cajon, “4100 m, I, Hocteipuek 1373 (A, SI). Tucuman: Sierras Calchaquies, 4000 m, 30-I- 138 BERYL SIMPSON VUILLEUMIER 1933, Burkart 5185 (SI); Tafi, Pabellon, 16-I-1908, Castillon 97 (F); Cerro Mufioz, Las Animas, 4600 m, 3—I-1916, Castillon 3304 (LIL); El I 15-I-IV-1924, Venturi 6332 (US), Los Chucos, 1-V-1926, Ven rturi 6237 (US). Catamarca: Laguna de Tesoro, 4600 m, 3-III-1925, Venturi 6238 (US); Santa Maria, 4600 m, 1-I-1925, Venturi 6241 (US). PROBABLE HYBRIDS BETWEEN PEREZIA COERULESCENS AND P, PINNATIFIDA PERU. Junin: Mt. La Juntay near Huancayo, 4700 m, 27-IV-1929, pa & Smith 29099 (NY). Cuzco: Oropeza Valley, Hacienda Guispicanchi, I- 1929, Herrera 2595b (US), Cuzco without locality, 3 3000-3600 m, VII- 1923, Herrera s.n. (US). Puno: San Antonio de Esquilache, 15000 ft, ri hee 741 ); near cae 3900-4000 m, 10-III-1965, Vargas 16237 US). Botrvia. La Paz: La Fabulosa, 15000 ft, 26-IV-1950, "Brooke 6301 & (F, NY). = pag In his treatment of the Compositae in the Chloris Andina, Weddell described most of the forms involved in the Perezia complex except P. pinnatifida which had been circumscribed forty years earlier by Humboldt and Bonpland. Although Weddell’s type specimens are quite distinct, evidence from collections now available suggests that he actually described hybrids in some cases and clinal extremes in others. If only the type specimens are considered, it is immediately apparent that Perezia coerulescens and P. nivalis of Weddell are the same species. The slight differences between them are in the spininess of the leaves and the outer bracts, and the width of the basal leaves. Perezia coerulescens has narrower, more dissected, spinier leaves than P. nivalis. However, one specimen of P. coeru- lescens from Bolivia cited by Weddell is indistinguishable from the type of P. nivalis. Two other taxa were later described which also, without doubt, fall within the variation of Perezia coerulescens. A variety of the species described as P. coerulescens var. amplibracteata, is iden- tical with the type of P. coerulescens except that the flower color is orange rather than blue. Another proposed species, P. nitidifolia Koster is also practically identical with one of Weddell’s original specimens of P. coerulescens and is also accordingly placed in synonymy with the latter. Part of the confusion in the application of the name Perezia coerulescens is possibly due to an illustration in Weberbauer’s (1945, Fig. 25). Apparently, many taxonomists who had not seen the type of P. coerulescens used this picture for identi- THE SYSTEMATICS AND EVOLUTION OF PEREZIA 139 fication of specimens. Unfortunately, the plant depicted was probably a hybrid between P. coerulescens and P. pinnatifida. Three other species described by Weddell, Perezia integrifolia, P. violaceae, and P. cirsiifolia are more similar to one another than to the types of P. coerulescens and P. nivalis, but are con- sidered here to fall within the range of P. coerulescens. The type of P. integrifolia (a very poor specimen) is similar to that of P. nivalis, and is transitional in morphology to the forms described as P. cirsiifolia and P. violaceae. The type of P. cirsiifolia is a bizarre specimen and again, could be a hybrid between P. coeru- lescens and P. pinnatifida. The only plants I have seen which approach the type in morphology are from a collection by Tovar from Huancavelica, Peri which also includes specimens showing a combination of characters that suggests introgression from P. pinnatifida into P. coerulescens. The type specimen of P. vio- laceae is similar to plants of P. coerulescens found in Argentina and treated as P. burkartii by Cabrera. A transition from the spinier type (Perezia coerulescens sensu stricto) to the broader leafed type (P. violaceae-P. burkartii) can be seen if a large series of specimens from central Pert to Argen- tina is examined. From Huanuco to Cuzco (Pert), almost all examples have dissected, spiny basal leaves and spiny outer bracts. However, starting at Huancavelica, the heads become pro- gressively broader and the bracts wider and less spiny. A mixture of forms can be found from Puno (Pert) across Bolivia. Three large collections from Bolivia (the Bang 1217 from the Bolivian Plateau; the Fiebrig 3172 from Calderillo; and the Steinbach 9827 from San Benito) all show combinations of characters associated with presumed different species. The three collections are similar in head size and outer bract shape and differ only in leaf size and shape. Since there is a trend from dissected to entire leaves dis- cernible from mid-Peri through Bolivia, it seems unreasonable to use leaf margin alone as a basis for separating the forms. All of the plants from southern Bolivia and northern Argentina appear to have spineless, non-dissected leaves although the leaf margins are sometimes ciliate or lobed. Two other species are considered here to belong with Perezia coerulescens in its species group. Both of them, P. pygmaea and P. pinnatifida, appear to be very closely related to P. coerulescens and there is evidence that P. coerulescens and P. pinnatifida 140 BERYL SIMPSON VUILLEUMIER hybridize in certain localities (see above). I have kept the two species separate for several reasons despite the fact that some intermediate specimens can be found. First, the habitats of the two taxa differ: P. coerulescens grows in wet, short grasslands; and P. pinnatifida in rocky, drier environments. Hybrids are prob- ably formed where the habitats of the two species overlap or where there has been disturbance of the pristine habitats by man. Second, Perezia coerulescens differs morphologically from P. pinnatifida by its flat, rather than inrolled, basal leaves and strigose rather than pilose achenes. The outer bracts of P. pinnati- fida are as long as the inner bracts and broad at the apex; those of P. coerulescens are shorter than the inner and lanceolate in out- line. (Compare PLATE 2-1 with 2-3.) Plants of P. pinnatifida are densely hispid whereas those of P. coerulescens are usually much less pubescent. There are also several morphological similarities between Perezia coerulescens and P. pygmaea. In fact, the two taxa may be conspecific but there is difference enough to warrant a separa- tion of the species until further work can be done. P. maea appears to have consistently only four or five basal leaves each of which have no more than four or five lobes on either side of the midrib. Both P. coerulescens and P. pinnatifida have larger, more numerous leaves with at least ten segments, although there are some populations of P. coerulescens with practically entire leaves. P. pygmaea also has comparatively fewer outer bracts than P. coerulescens, and pilose achenes. (Compare PLATE 2-1 with 2-2.) 26. PEREZIA PINNATIFIDA (H. & B.) Wedd. Homanthis pin acti Humboldt, Bonpland & Knuth, Nov. Gen. Sp. Plant. 4:308. 1820 (quarto « edition Homoeanthus pinnatifidus (H. & B.) Sprengel, Sys. Veg. 3:503. 1826. Homoianthus pinnatifidus (H. “3 -) D. Don, Trans. Linn. Soc. I. 16:209. Clarionea pinnatifida (H. & B.) de Candolle, Prodr. 7: ag 1838. Perezia sab Sg natifida (H. & B.) Weddell, Chloris Andina 1:40. 1855. Compact rosette plant 2-12 cm tall. Rootstocks Seat tous. Flowerin stems hidden in the foliage, bearing 3 or 4 sheathing, lyrate to lanceolate, THE SYSTEMATICS AND EVOLUTION OF PEREZIA 141 obtuse and dentate stem leaves. Basal leaves numerous in a full rosette, e se i lyrate in outline, obtuse, deeply dentate with the ents often condupli- cate and with short cilia along the margins which tends to “seal” the fold; leaf bases attenuate or flaring, membranous; le 7 m de, c to obtuse, dentate at the apex, 4-10 mm wide, 9-23 mm long, densely glandularly pubescent. Inner bracts lanceolate, acute, 2-6 mm wide, 12-24 mm long, slightly pubescent at the apex. Pappus setose, brown, 1-1.7 cm h, yellow, white or “pinkish-blue;” 1.5-4.3 cm long with ligules 5-12 mm; 14-4 r capitulum. Achenes with glandular tri- Distribution: perhaps in Ecuador; in Pert at very high elevations south to northern Bolivia (Fig. 26-3). Altitudinal range 3000-5000 m. Flowers March to May (PLATE 2-3). Representative specimens: peru. Lima: Huarén, 12-VI-1922, Macbride & Featherstone 1136 (GH); Rio Blanco, 15000 ft, 20-25-III-1923, Macbride Featherstone 3031 (F, GH, US); Auquimarca, III-1947, Peraldo 3280 (F); Valley of the Rimac, 4850 m, Raube ¢ Hirsch P 94 (NY). Junin: Yauli, 13500 ft, 25-V-1922, Macbride & Featherstone 929 (F, GH, US); above Casapalca at Mina Frei, 30-V-1965, Vuilleumier 259 (GH). Huancavelica: Huancavelica, Paso de Chonta, 4800-4900 m, 8-V-1955, Tovar 2947 (GH); Pisco, Rio Pisco, 4600 m, 10-III-1957, Raube & Hirsch P 399a (NY). Puno: San Antonio de Esquilache, 16000 ft, Stafford 719 (BM), 15000 ft, 9-ITI-1937, Stafford 1280 (F, BM). sorivia. La Paz: Apacheta de Chuchu, 13-IV-1860, Mandon 27 (P); Larecaja, vicinity of Sorata, between Pongo and Amlaya, 3600 m, 9-IV-1857, Mandon 20 (GH, NY, P, US). Perezia pinnatifida is the second member of the P. coerulescens complex. The species was described originally by Humboldt and Bonpland from an Ecuadorian specimen but it has not been re- ported since from that country. The habitat of P. pinnatifida is rocky outcrops at very high elevations, where individual plants nestle with their heads hidden in the basal rosette (PLATE 2-3). This characteristic aspect and the broad, long outer bracts make P. pinnatifida a rather easily recognized species. The confusion which has sometimes arisen in the identification of some specimens is apparently due to the presence of hybri Is between Perezia pinnatifida and P. coerulescens. Some intermedi- ate specimens have basal leaves like those associated with P. pin- natifida, but have strigose (rather than pilose) achenes and gla- brous foliage. (See pLaTe 2-1 and 2-3.) Other specimens like P. coerulescens in aspect have the pubescence characteristic of P. pinnatifida. Both species occur in all areas from which I have seen intermediate specimens. Putative hybrids have not been reported from Argentina where only one of the two species grows. 142 BERYL SIMPSON VUILLEUMIER 27. PEREZIA PYGMAEA Wedd. Perezia pygmaea Weddell, Chloris Andina. 1:40. 1855. Type: BOLIvIA. a Paz: Ravine of Chuquiaguillo, near La P , 1851, Weddell s.n. (P). e with up to 7 rounded marginal lobes, of which the terminal lobe is the largest; leaves with a tendency to apne conduplicate upon drying; leaf bases attenuate, 4-8 mm wide, 1 m long, glabrous or with some scat- tered trichomes. Capitula one per eam stem, not more than two per plant, narrowly campanulate, 9-17 mm wide, 15-20 mm long; upright. In- ovate, acute, entire, or very slightly dentate at the apex; 2-5 mm wide, —l mm lon ng, labrous, broadly scarious. Inner bracts longer than the outer, lanceolate, mucronate, 2-5 mm wide, 10-14 mm long, glabrous, scarious on the edges. Pappus setose, brown, 8-15 mm ng a eT white, blue, or m glabrou Paces in the Andes from aang Pert to ane ni (Fig. 26-2) at as elevations from 4000-5000 m. a ring from March to June. (PLATE “ra Representative specimens pitas He near Ce 4650 m IV-1942, Grant 7576 (F, CH), VaeciGe 15500 ft, 21-V-1922, ia & Featherstone (F, S), Mina Frei above Casapalca, 5000 m, 30-V-1965, Vuilleumier mr (GH). Huancavelica: Huancavelica, Tansiri cerca a Manta, 4400-4500 m, 31-III-1953, Tovar 1152 (GH); Castrovir- reina, near Laguna Choclococha, 4500-4600 m, 5—-V-1955, Tovar 2920 GH). Puno: Melgar near Nufioa, 3900-4000 m, "10111-1965. Vargas 16246 (US). Botivia. La Paz: Cordillera = Coroico, 5000 m, 22-IV-1857, Man- don 19 (F, GH, NY, P, US). arncentina. bd Tres Cruces, Mina Aguilar, 4190 m, 29-IV-1965, Vuilleumier 242 (G Perezia pygmaea forms mats of ee crowded plants closely appressed to the damp soil at snow line in the Andes of central Perti south to northern Argentina. This species is considered here to be a distinct member of the P. coerulescens complex, although it may ultimately be shown to be a high altitude (and consequent- ly dwarfed) form of P. coerulescens. However, there is some evidence that it is a good species and should be maintained until further field work can be done. At several localities (e.g., Junin, Per and Ravine de Chuquiag- uillo, Bolivia) both Perezia pygmaea and P. coerulescens have apparently been collected together, suggesting that two taxa are involved. In these areas plants of P. coerulescens have very den- tate outer bracts and very deeply parted leaves and sympatric specimens of P. pygmaea have more entire bracts and basal leaves with only four or five lobes. (Compare pLaTE 2-1 with 2-2.) In some localities (such as in northern Argentina), specimens THE SYSTEMATICS AND EVOLUTION OF PEREZIA 143 rs Sep | Pelee se fro Bout R PINNATIFIDA eng Fic. 26. eae 3 of Perezia coerulescens, P. pygmaea and P. pinnatifida, the ree members and P. pilifera. Arrows indicate areas of possible mater aah between da. the P. coerulescens group, P. coerulescns ral P. pinnatifida 144 BERYL SIMPSON VUILLEUMIER of Perezia coerulescens approach P. pygmaea in morphology except that they have strigose achenes. The third member of the Perezia coerulescens group, P. pinnati- fida is also known to grow sympatrically with P. pygmaea (ie., Mina Frei in central Peri [Junin] ) where they occupy separate habitats. Plants of P. pinnatifida prefer the rocky outcrops, where-. as those of P. pygmaea grow on flat moist soil. Morphologically, the two species are also quite distinct. Perezia pinnatifida has comparatively large basal leaves which are inrolled and which hide the capitula. The basal leaves of P. pygmaea are appressed to the ground and the heads are held above them. The outer bracts of P. pinnatifida are long and thickened at the apex and obscure the inner, shorter, bracts. The outer bracts of P. pygmaea are shorter than the inner and are ovate in outline instead of elongate as in P. pinnatifida. (Compare PLATE 2-2 with 2-3.) 28. PEREZIA POEPPIGH Less. Perezia ond aca yeas Synop. Comp. 411. 1832. Type: cute. “Boreal Andes,” Poeppig s.n. (P). srr saieag I have, therefore, chosen the Cuming specimen as lect totype. erezia virens (D. Don) Hooker & Amott, Comp. Bot. Mag. 1:34. 1835. Clarionema virens (D. Don) Philippi var. pare ace Phil. pi nei 33:124. 864. Type: cH 855. Chota : ge be Phil., Anal. Univ. Chile 87:301. 1894, “Type: CHILE. Colchagua: Cordillera de San Fernando, I-1884, Herth s.n. (SGO logge oii remyanus Phil., Anal. Univ. Chile 87:310. 1894. : E. O'Higgins: Cordillera de ‘sora Las Lenas, I-1887, Philippi 2252 (Sco, Isotype LP Homoeant. us brevicaulis Phil., Anal. Uni iv. Chile 87: sari 1894. Type: nana Phil. Anal. Univ. Chile 87:303. 1804, Type: CHILE. Clarionea Coquimbo: Illapel, Las Mallacas, I-1888, no collector (SGO). Small, bright, rosette perennial herb 4-13 cm tall. Stems woody ges eep oblong teeth or scalloped, edges of segments with short cilia or spines; leaves attenuate at the base; wi a 3-17 AN length 1 THE SYSTEMATICS AND EVOLUTION OF PEREZIA 145 mm wide, 15-27 mm long; composed of 4—5 rows of bracts. saben bracts lanceolate, acute, algntly spiny, 2-4 mm wide, 6-14 mm long; sur face with glan ular punctate dots or a few scattered glandular Ais slo scarious along the margins. Inner bracts lanceolate, acute, entire, 2-4 wide, 9-21 mm long, rigid, covered with glandular punctate ain scarious along the margins. Pappus setose, beige, 13-19 mm long. Florets cream, ts 9 m_ long; Distribution: Tas to the Chilean side of the Andes from northern Coquimbo to mid-Colchagua at elevations of 1700-3200 m (Fig. 27-2). Flowering season from December to March. Representative specimens: CHILE. Coquimbo: Cordillera de Ovalle, 3131 m, I-1837, Gay 425 (P); Dpto. Illapel, vue Escondida 2640 m , 21-XII- 1 H ui 936, Morrison 16966 (GH). Aconcagua: eITo Caquis, 15 km east of Melén, 1750-2040 m, 14—XII- 1935, Morrison 16899 (GH, LIL); 6 km before Portillo, 2450 m, 16-I-1964, ‘Marticorena & Matthei 616 2 (CONC), Portillo, 2870 m, 6-III-1954, Ricardi 9846 (CONC). Santiago: Alhué, Monte Cantina, 9-1-1939, Barros 2025 (LP, SI); Rio Yeso, Laguna Negra, 13-I-1945, Biese 930 (LIL), Perez Caldera, 2600 m, 17-I-1964, Marticorena ¢r Matthei 645 (CONC). Colchagua: San eer Vegas del Flaco, 1250 m, 21-I-1930, Montero 1757 (GH). Perezia poeppigii is limited in distribution to the area south of the Atacama desert and north of the Nothofagus forest (Fig. 27-2) as is true of many other endemic Chilean angiosperms. Perezia poeppigii is the only species of Perezia to have this geo- graphical pattern, although P. carthamoides has a series of dis- tinctive populations in the same area. The habitat of P. poeppigii seems to be rocky crevices in the scrubland or monte of the longitudinal valley of central Chile. ough the range of Perezia poeppigii is fairly restricted, there is some geographical variation in morpho ogy trom nort to south. In the central part of the province of Santiago at Alhué (Monte Cantillana) and south to Colchagua, plants have leaves which are scalloped, spiny and not as dissected as those of other populations. Plants from this area (described as Homoianthus prystiphyllus Remy ) are also more elongate than those from other re Philippi described four other species considered here to be geographical races of Perezia poeppigii. Three of the four (Homo- eanthus remyanus, H. brevicaulis, and Clarionea caulescens) were 146 BERYL SIMPSON VUILLEUMIER described from central Chilean specimens and belong to the same geographical race as Remy’s Homoianthus prystiphyllus. Philippi’s fourth species, Clarionea nana, was described from a northern Chile specimen and is merely a small plant of the form originally described as P. poeppigii. On morphological grounds, it is evident that Perezia poeppigii is part of the P. recurvata species group and is, in fact, probably similar to the stock which gave rise to both P. linearis and P. recurvata. A logical sequence of morphological specialization leading to the needle-like, recurved leaf of P. recurvata would seemingly begin with a broad, flat laminar type of leaf, progress to a linear, flat leaf, and finally, by inrolling of the margins, pro- duce the type now found in P. recurvata. Such a sequence is visible from P. poeppigii through P. linearis to P. recurvata. These three species also share the characters of a similar achenial trichome type (Fig. 3-2, Table 3), very turbinate heads, and stiff, lanceolate involucral bracts. The only two species with which Perezia poeppigii might be confused are P. linearis and P. carthamoides. Plants of P. poep- pigii with rather entire leaf margins approach P. linearis in aspect, but can be simply distinguished because the leaves are larger and do not have the dense even cilia along the margins which is characteristic of P. linearis. Also, the florets of P. linearis are al- ways blue whereas those of P. poeppigii, although sometimes blue, are more frequently cream, yellow, or red. Small specimens of Perezia carthamoides with reduced basal leaves have sometimes been misidentified as P. poeppigii but the former can always be distinguished from the latter because of its broadly hemispherical, rather than turbinate, capitula, and its broadly scarious ovate bracts. In the province of Santiago, Chile, where the two species are sympatric, P. carthamoides has upright panicles of several heads whereas plants of P. poeppigii have monocephalous (rarely dicephalous) flowering stems. 29. PEREZIA LINEARIS Less. Perezia eee te Synop. Comp. 412. 1832. Type: CHILE. Bio Bio: Austral Andes near Antuco, shal ta 767 (P, Isotypes Homoianthus Maat (Le SS. ) de Candolle, Prodr. 7: innaea Linares: Cordillera de Linares, II-1856, Germain sn. (SGO). Homoianthus pectinellus Gandoger, Bull. Soc. Bot. Fr. 18:45 (65 of THE SYSTEMATICS AND EVOLUTION OF PEREZIA 147 total series, 18 of Ser. pele ites Type: ARGENTINA. Patagonian Andes, 1100 m, Buchtein ( type not s ne all. species fecdirg | to form loose mats by branching at the base and creeping over the ground. Plants 4-31 cm tall, but prostrate if longer than 15 cm. Flowering stems densely pubescent with oandules trichomes; bearing 1-15 clasping, lanceolate, acute, and densely ciliate stem leaves. Each stem leaf up to 3 mm wide and 2.5 cm lo ong. Basal leaves in sha forming small rosettes, individual leaves linear but slightly spathulate, mucronate, and densely ciliate along the margins; leaf edges never recurved, rather frequently mgs aa upon drying; 1-4 mm wide, 1.2 em lon ae brous or with glan ot punctate dots. Capitula one per “flowe ing stem, pre shaped, 24.4 am ads, 2-3.2 cm long; — — ‘urbinate, mm wide, 12-3. m long; —— of 3-6 r f bracts. Outer Gat lanceolate, acute, eBinte wide, 5-19 mm He usu, ay gla- brou: s but sometimes w ith a few scattered | glandular Se a ae obsstemally Florets blue or white, outer florets 1. 33. mT. with li m “he about 8-16 per capitulum. Ovaries 1 ong with scattered double ure achenes to 4 mm long, less abeitcar t than the ovaries. Re- ceptcl covered with tufts of golden me omes. ution: in ei cape in a Andes of Neuquén south to the region of en Argentino long the Cordillera from Concepcién to Chile Aysén ‘Fig. 27-3). poe Ry state from 600-1600 m. Flowering January o Mar Seatietlee specimens: ARGENTINA. Neuquén: Parque Nacional Nahuel Huapi, subido al refugio Cerro Colorado, 1200 m, 24-II-1951, Diem 1875 (SI). Rio Negro: Parque Nacional Nahuel Huapi, Cerro Belvede re, 21- IH-1934, —— 107 (GH), Cerro Goye, 14-II-1965, Fopiaaneed 203 (GH); Rio Casa de Piedra, 1100 m, 10-I-1929, Cordoni 252 (US); Lago Hess, 10-I- gi Moyer 8120 (A). Chubut: iio. doy Putrachoique, I- TS tino, West o Santa Cruz Rive At 1808, botoe 159 (GH ); Penin- = @ a ari — — ae iv) Cand 3 = 8 ~ & 3 3 a rj © 2 ~ Wn -— — Se iS) ga ° s ® jon) © — l —_ e€ Wittes 49 (NY). cute. Concepcién: Province de pen pre: 1839, Ga 284 (P). Colchagua: Cajon n de Azufre, II-1831, Gay 946 (P). Maule: Cor- dillera de Maule, 1885, Germain s.n. (P). Linares: Cede de Linaris, el Bio Bio, 1000 m, 16-1 1041, Pfister may, II-1930, Sinko "1387 Pree 5 eeaonahs del Rahué con el Bio Bio, fister i i 0 m, II- : e 2 7 ® ® olhua aguna 9 Morrison & eked 17464 (GH). Aysén: Estero Las Mulas, afluente del Rio. Ibanez, 2-II-1962, Behn s.n. (CONC); region del Lago Buenos Aires, Valle Leon, cerca del Rio Meliquina, 3-II-1939, Renézell s.n. (SI). In clearings in the higher parts of the Nothofagus forest and along the edges of the forest in Patagonia, Perezia linearis is a 148 BERYL SIMPSON VUILLEUMIER 22 p RECURVATA ~ “RECURVATA™ "TRICEPS" C) "BECKI" So nani of cetecone carthamoides of the P. ba group and the three a of t - recuryv es group: P. poeppig linearis, and P. recurvata. Fic. 27-4 shows . © distribution P ‘the three Eesti present in P. recurvata. See also Fic. 28 a THE SYSTEMATICS AND EVOLUTION OF PEREZIA 149 fairly common species (Fig. 27-3). It seems to prefer well drained soils and some sun, but does not occur to any extent on the true Patagonian steppe, nor in the high puna well above timberline. Thomasson (1959) reported the species growing with Fuschia magellanica (Onagraceae) and Calceolaria tenella (Scrophulari- aceae) in a more moist habitat than the localities in which I have seen the species. The species varies little geographically despite its extended latitudinal range. It is possible that Perezia linearis is actually one of the poly- morphic forms of P. recurvata because plants of the two species from the same locality are exceedingly similar except in the char- acter of recurving of the leaf. Mixed collections of the two species are common from the areas of sympatry. The only constant differ- ence between the two species is that P. linearis has flat leaves of thinnish texture with a dense even row of cilia along the margins and bracts with evenly ciliate margins (Fig. 29-a). Perezia recur- vata has thick leaves which are strongly recurved and have spines on pseudomargins and bract edges (Fig. 29, b to r). No specimen of P. linearis has been seen which has leaves that tend to recurve. In fact, the leaves of P. linearis often become conduplicate upon drying. Furthermore, no individuals have been found which have a trace of spines or long trichomes on the upper surface of the leaf blade. There also appears to be a habitat separation of the two species. Perezia linearis grows within the Nothofagus forest and along the forest edges. P. recurvata is a puna and steppe species. Because of the consistency of the leaf characters and the eco- logical separation, the two are retained here as distinct taxa. Further investigations will show whether or not this interpreta- tion is correct. Undoubtedly, the two are very closely related and were derived from a common stock. The ancestral form common to the two probabably had flat leaves much like those of Perezia linearis. 30. PEREZIA RECURVATA (Vahl) Less. Perdicium recurvatum Vahl, Skriv. Nat. Selsk. Kigb. 1:13. Tab. 7. 1790. Type: cHiLe. Magellanes: Straits of Magellan, Commerson s.n. (C, Isotype P, CONC). Chaetanthera recurvata (Vahl) Sprengel, Sys. Veg. 3:503. 1826. Perezia recurvata ) Lessing, Linnaea 5:21. 1830. Clarionia recurvata (Vahl) D. Don, Trans. Linn. Soc. I. 16:206. 1830. 150 BERYL SIMPSON VUILLEUMIER Perezia recurvata (Vahl) Less. var. sessilis Dusen, Arch. Bot. Stockh. 7(2):46. Taf. 6(4). 1908. Type: ARGENTINA. Chubut: Colonia San Martin, Homoianthus echinulatus Cassini, ‘Dict . Nat. 38:458. 1825. Type: CHILE, In insulis Maclovanis (Falkland See ’ Urville é> Gaudichaud s.n. (Pd: Perezia doniana Lessing, Synop. Comp. 412. 1832. Type: CHILE. without locality, Ruiz & Pavon s.n. (type not seen Homoianthus donianus Gree Remy in Ga ay, Fl. Chile 3: aot 1849. Perezia reflexa Meyen, Reise um die Erde 1:311. 1834. Type: ¢ E. Col- chagua: Cordillera de San Fernando, 31-I-1833, Meyen s.n. (type ‘dontayel at Berlin, Photo 16086, GH). Homoianthus inermis Me eyen & Walpers, Nov. Acta Acad. Leop.-Car ol. 19 (Supp. 1):290. 1843. An eee name for the same specimen described as P. reflexa by Meyen in Perezia beckii Hooker & Arnott, oS Bot. Mag. 1:34. 1835. Type: ARGENTINA. Patagonia, Dr. Eights 62 Homoianthus aT se ares Philippi, ee Univ. Chile 2:396. 1862. Linnaea 33:124. 1864. Type: ARGENTINA. Mendoza: Portillo, 1861-1862, Diaz s.n — erezia gerry (Phil.) Reiche, Anal. Univ. Chile 116:437. 1905. FI. Chile 4:455. 1905 Homoeanthus triceps Philippi, Anal. Univ. Chile 87:307. roger Type: cHILE. Bio Bio: Guaieltué, II-1887, Rahmer s.n. (SGO, Isotype Perezia triceps (Phil.) Reiche, Anal Univ. Chile 116:431. 1905. A Chile 4:449. 1905. Perezia patagonica Spegazzini, Rev. Fac. Agron. Vet. 3 ae :540, 1897. Type: ARGENTINA. Santa Cruz, 1882, ame sn. A Perezia patagonica Speg. var. intermedia Speg., Fac Agron 3(32-33):615. 1897. Type: ARGENTINA. Chubut: ona locality, "1889, ct : erezia flavescens Dusén, Arch. Bot. Stockh. 7(2):46. 1908. Type: ARGEN- TINA. Puerto oa pies iL “XII- 1904, Dusén 5355 (Type destroyed at Berlin, Photo GH, LIL; Isotype HBG). Homoianthus patagonicus Gandoger, Bull. — ead Fr. 18(Ser. 4):45. 1918. Non Perezia patagonica Spegazzini. Type NTINA. Rio Negro: Bariloche, 1100 m, 19-II-1905, Buchtein 1339 PCHBG, Isotypes GH, US). An illegitimate name since it is a later homonym of Perezia patagonica Speg. Small mat forming plants extremely woody and branched at the bas e and with decumbent or upright stems; 4-30 cm tall. Stems terete, ional with a few glandular trichomes below the head; sometimes streaked with red. m ing in size as they — the capitulum; lanceolate or linear in outline, argins recurv r i spines, or with a single or double row ‘ot stiff oa wake le leaf base flaring and clasping; 1-5 mm wide, 7-37 mm long; surface smooth, glabrous, or in some cases with furrows running at right angles to the midrib. Capi 1-3 per flowering stem. Flowering stems axillary, ‘event present per plant Individual capitula 1.5-2.5 cm wide, 9-25 mm long, upright. Involucre hemispherical or turbinate, 9-19 mm wide, 10-25 mm long; composed of THE SYSTEMATICS AND EVOLUTION OF PEREZIA 151 long stiff white spin m il sometimes glabrous but usually with glandalar trichomes scattered along the surface, scarious along the edges, sometimes reddis pex. In racts_ lanceolate, acute, entire, 1-5 ide, 10-2 m long, usually with a few glandular an OR number: 4 (or 26). Distribution: from C ane agen in Chile south along the Andes through Tierra de] Fuego. In Argentina south from Mendoza to Tierra del Fuego and east to the Atlantic Ocean. Also found on the Falkland Islands (Fig. 27-4). Flowering October to March (PLATE 2-4). Representative specimens: ARGENTINA. San Juan: Department of Inglesia, Cordillera de Colanquil, Brackenbush s.n. (CORD). Mendoza: Paso Cruz, 0 m, O. Kuntze 103 (US), 192 (NY, US); Valle de Calmu-cé, 14-II- 1940, Burkart, Troncoso & Nicora s.n. (SI); Malalluce, Cerro Miraus, cerca de Ruta 40, 18-I-1956, Castellanos 3514 (LIL); Department of Beltran, region del Rio del Fuego, III-1902, Holmber & Calcagnini 333 (BAB); Mision Rio Grande, hat pee 119 (SI); Isla de los Estados, 4 . ; BAB AND ISLAND Hearn eee n. (GH); West F Falkland Islands, Rocky Cove, I, grr . (K); East ¥ aaa Sparrow Cove, north of Point Stanley, I, Slade Fa 27/50 (BM). cu E, Cole hagua: San Fernando, Vegas del Flaco, 10-11. 7464 (LP). Talca: Laguna del Maule, 2200 m, I-1943, Behn s.n. (CONC Valdivia: Lechler 1181 (HBG). Aysén: Rio Nireguao, Estancia Banos oD ist Ricardi s.n. (CONC); Puerto Natales, 16-I-1933, Jara s.n. ee iC); Cerro tea, 5 km north of ay Natales, 8-I-1939, Eyerdam, B & Gron- ae 24191 (GH); Carmen de Patagones, 9-X—1937, Miccio dS (LP); Orilla, norte del Rio Rape, 10-IX-1874, Berg 119 (LP). Neuquén: Chos Malal, 24-I-1964, Boelcke ates: ~_% Traful, 17-I-1935, Cabrera & Job 408 (LP); Volcan Tro Rahui Pass, 25-IJ-1888, Kurtz 6146 (CORD); Lago Hochalatanen: "2-1-19 945, O'Donnell 2286 (LIL). hos Negro: Bariloche, base of Cerro Otto, 9-II-1965, armen 196 (G Pilcaniyeu, 20-II-1 1938, Nicora 3658 & 3674 (SI); erde, camin 10 Verde, camino de San Antonio a Madryn, 14-II-1938, mercer ag & Birabén 152 BERYL SIMPSON VUILLEUMIER 440 (LP). Chubut: Esquel, 20-I-1945, Castellanos s.n. (LIL); Comodoro Sirah 4—XI-1945, O’Donnell 3425 (LIL); Puerto Piramides 8-I-1914, n ¢ Hauman 201 (SI); Bolsén, 5—10-I-1901, Illin 2 (HBG); Cholina, Hype Illin (BAB); La Sinica, 600 m, 21-I-1945, Rohmeder 18 (A, LIL); Dpto. 16 de Octobre, Colonia Cushamen, 31—XII-1947, Kraprovickas 3793 (BAB); Colonia Sarmiento, 24-III-1902, Koslowsky s.n. (BAB); Puerto San José, 11-XII-1904, Dusén 5355 ( HBG). Santa Cruz, south shore of Lago Argentino, 30 km west from the Santa Cruz River, 1907-1908, Furlong 158 (GH); Cordillera Cristales, II, James 219 (BM); Est. Fitzroy, 24—XII-1950, Sleumer 1255 (LIL); Lago Sons Martin, Rio Fosiles, 900 m, Dusén s.n. (LIL); Canadon Leén, 24—II-1936, Birabén ¢& Birabén 117 (LP); Lago Cardiel, 27-II-1936, Birabén & Birabén 140 (LP); Rio Gallegos, Killik Aike, Brown 78 (NY); Tehuelches, ca. 300 m, 28-XI-1928, Donat 63 (GH); (SI); Straits of Magellan, Elisabeth Island, I-1888, Lee s.n. (US); U Ultima Esperanza, 5-I-1931, Donat 388 (GH); Santa Catalina, 31-I-1936, Behn sn. (CONC); Bahia Felipe, Estancia las Rosas, 23-I-1952, Pfister s.n. (CONC). As is suggested by the large number of synonyms included here under Perezia recurvata, the species is polymorphic and widely distributed (Fig. 27-4, Fig. 28). Several rather consistent pheno- types recur throughout the range of the species. These phenotypes and several of the intermediate populations have been described as separate species, the separation of which was made on the “ LEAVES WRINKLED O -~ LEAVES SPINY A 7 L LEAVES SMOOTH ®& om A a Z o A oo ny : (BECKEN) A < oa a 5 (TRICEPS) foe & A A 0 . 1): oh = Ka *x0 B00 Ox a 3 * & Of OO O W 4 & Oe ¥* OO exe) Oo OC OC'O0 % Oo (RECURVATA) LENGTH OF LEAF (CM) 8. Graph of leaf length vs. ond bract length of specimens of Perezia recurvata showing ak intergradation of these characters frequently used to separate the species into three distinct taxa. Each pence represents one specimen. THE SYSTEMATICS AND EVOLUTION OF PEREZIA 153 Fic . Variation in the leaves of Peeisine recurvata. Leaves b, c, d, e and / are the “beki” ee Leaves f, g, and q are the “triceps’’ type. Representatives m, and r are eal sdb ing ‘aera ee se clic Leaf a is from a plant of 2 Fisuee All natural size basis of the appearance of the leaf pseudomargins, the leaf surface, and the amount of curvature of the outer bracts. A brief discussion of the different phenotypes and their probable evolu- tionary history is included here to explain their inclusion into one species. The phenotype originally described as Perezia recurvata has heads with rounded bases, upright involucral bracts, leaves which are transversely wrinkled and which have small spines along the edges (Fi ig. 29, leaves h, i, k, m, r). This “recurvata” form is common in southern and southeastern Patagonia and is found on the Falkland Islands. Along the east coast of Patagonia and straying across the table- land is a form which has long stiff leaves without transverse wrinkles and much longer, stiffer white spines along the pseudo- margins of the leaves and outer bracts than the eastern popula- tions (Fig. 29, leaves b, c, d, e, 1). The bracts of this form are always curved outward and the inner bracts are long and quite scarious. The pappus is usually pure white and the flowers tend to be yellow, rather than blue as they are in the “recurvata” form. This phenotype was described as Perezia beckii by Hooker & Arnott and is here referred to as the “beckii” phenotype. Another type described by Philippi as Perezia (Homoeanthus) triceps has several heads (usually two or three) per flowering stem. Philippi described this form as having entirely smooth leaf edges, but Reiche (1905) stated that Philippi was mistaken and that the leaves usually have small spines along the pseudomargins. I agree with Reiche; in fact, the type specimen has small spines along the leaf edges, but they are hard to see with the naked eye. 154 BERYL SIMPSON VUILLEUMIER Because Philippi described Perezia triceps as having smooth leaf edges, the name “triceps” has been applied to populations of Perezia recurvata in Argentina which do have more or less entire leaf pseudomargins (Fig. 29, leaves f, g, j, 0, p, q). This form, designated “triceps” here, has bracts which are usually curved outward as they are in the “beckii” form, but has blue rather than yellow flowers and does not have the stiff white spines of the “beckii” form. There is a tendency for plants in these populations to have 2 or 3 heads per flowering stem. Previous workers, also conscious of the complex situation, have merged the forms to various, but not necessarily identical, de- grees. Hooker saw the plants in the field and observed in the Flora Antarctica (p. 322, 1847) that Perezia beckii was extremely vari- able in the amount of spines on the leaf margins, and some plants lacked them altogether. The species described as P. patagonica, P. patagonica var. intermedia and P. reflexa all seem to me to be merely smooth leaved plants of the “beckii” form. Reiche, in the Flora of Chile (1905) observed that Perezia linearis, P. pectinata, P. triceps, P. doniana, and P. reflexa could probably be grouped into two or three species. He felt that one good species would be P. linearis (which is maintained in this work as a distinct species) with flat, non-recurved leaves. Wheth- er or not the plants with recurved leaves constituted one species, he felt, depended on whether future investigations showed that plants with monocephalous and polycephalous flowering stems occurred in the same population. Evidence now demonstrates that both types of plants can come from the same population. As is clearly shown in Fig. 28, there is no tendency for the three principal phenotypes to cluster into groups when “important” characters are plotted. Although there is variation, the plants show complete intergradation in the size of the bracts and leaves. Thus the only character which could separate the presumed species would be the leaf margin (and the bract margins, but these are correlated with the leaf margins). However, even this character is completely unreliable. In areas where distinct phenotypes come into contact (Fig. 27-4 at such points as Lago Cardiel, Pilcaniyeu, Rio Gallegos, Lago Argentino—all in Argentina), intermediate forms are abun- dant and there is a complete sequence of leaf types (Fig. 29). Yet, two phenomena present in Perezia recurvata still need ex- THE SYSTEMATICS AND EVOLUTION OF PEREZIA 155 planation. First, why do the major phenotypes occupy more or less defined geographical ranges (Fig. 27-4) and, secondly, why are there plants of extremely variable morphology (i-e., in leaf margin) even well within the range of a given phenotype? The complex type of variation seen in Perezia recurvata could have resulted from two causes—or a combination of the two. This species could be composed of populations which had been iso- lated at some period and underwent a small amount of morpho- logical divergence but little or no reproductive change. After the barriers separating the populations were removed, the forms ex- panded their ranges and came into secondary contact. In the areas of secondary overlap, a stepped cline in morphology would be visible. This type of narrow band of intermediate forms be- tween recognizable geographical races (see distribution map, Fig. 27-4) in such areas as Pilcaniyeu, Lago Cardiel, and Rio Gallegos approximates the theoretical case of secondary overlap between partially isolated forms of the same taxon. A second possibility is that the phenotypes now present in the species are simply the result of selection following a micro-ecolog- ical gradient. There is some evidence that this is the case in the populations described by Hooker where plants seem to have dense spines randomly along the leaf edges, or be entirely smooth margined. Controlled plantings of a smooth leaf form from Bariloche, Argentina (the “triceps” form) were made at Cam- bridge, Massachusetts. Under the greenhouse conditions, the plants became elongate and had longer leaves than the plants from which the seeds had been taken. Also, the leaf edges of the Cambridge plants bore small spines on the leaf margins. The external morphology is, of course genetically determined, but in situations where the environment is variable, the plants seem to have the potential for some morphological modification. Such a situation is common and has been well understood since the work of Clausen, Keck and Hiesey (1940, 1945, 1948). Both of the factors mentioned seem to underlie the pattern now seen in Perezia recurvata. There is definitely some modification due to environmental conditions, but one phenotype can never completely change into another. However, over a period of gen- erations, with a necessary amount of selection pressure, any of the forms could be produced. In the case of P. recurvata, I feel that selection acted on three isolated groups of populations. One 156 BERYL SIMPSON VUILLEUMIER “pro-recurvata” series of populations was isolated in southeastern South America, near or on Tierra del Fuego and the Falkland Islands. Another “pro-triceps” group of populations was isolated in northwestern Patagonia in the region near Nahuel Huapi. The third cluster of “pro-beckii” populations would have been iso- lated in northeastern Patagonia somewhere south of Bahia Blanca. The factors which caused the isolation of these populations would have been the series of Pleistocene glaciofluvial lakes and rivers which abounded in Patagonia during the Ice Ages. After the Pleistocene glacial retreats and the post-Pleistocene drying, the three groups of populations reexpanded their ranges and pro- duced the pattern of secondary contact now visible. The question now arises as to whether it is necessary to give the forms recognition as subspecies or varieties. A subspecies is usually an allopatric population or series of populations distinct enough to be recognized as belonging to a defined taxon (Mayr, 1963, p. 672). In the case of Perezia recurvata, all the forms come in contact and form intermediates which would be impossible to place in one or another of the “subspecies.” However, it must be admitted that there is only a very narrow zone of intermediacy between two forms apparent from the specimens I have seen. Nevertheless, I have acted to keep the complex as a single species without subspecific parts, fully recognizing it to be highly poly- morphic and variable. EXCLUDED SPECIES l. Perezia lanigera Hooker & Arnott, eee Bot. Mag. 2:42. 1836. Type: ARGENTINA. Port Desire, Darwin 314 (K). Perezia — Spegazzini, Rev. Fac. Agron. Vet. ~ 1897. Type: ARGENTINA. Rio Santa Cruz, 1897, Spegassint “(ype no is species is excluded from the genus ecau has dense of Perezia. Similar trichomes were described for the genus Trixis by Sm (1919) and for Soe by Hess (1938). The interior substance of this type of trichome is extruded when the achene becomes wet. Obvious usly, however, the species belongs in neither Trixis nor Senecio. Its exact generic placement must ee Sapp work on the other genera of the Nassauviinae. 2. Perezia glandulosa Meyen, Reise um die Erde 470. 1834. Meyen’s description is totally inadequate and I can find no specimen annotated by two were merged, it seems best to avoid further chiapticatians by excluding Meyen’s name. THE SYSTEMATICS AND EVOLUTION OF PEREZIA bioté Perezia spathulata ee Stator Univ. Chile 87:300. 1894. non Clarion spathulata Lag. =Perezia viscosa Lessing). : Curico: Cordillera Es aa Restate, 1889, no collector (SGO). ei According to Cabrera (Compuestas Bonaerensis, Rev. Mus. La Plata II. 4:379. 1941) this species is a synonym of Trixis stricta (Sprengel) Lessing. LITERATURE CITED AHLFELD, F. aAnp L, BraniSa. 1960. Geologia de Bolivia. Instituto Boliviano de bia as Paz, Holivia: Aston, R. E. 1967. oe Systematics. Evol. Biol. 1:197-—305. ALsTON, R. AND 2. L. 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IV. The Mutisieae. Am. Jour. Bot. 16:297-313. INDEX 161 INDEX? ne 6 Acour ay an iz Anatomy 19 Aster magellanicus 119 ci cag magellanica 119 multiflor pinnatifida 140 pungens 90 recurvata 149 Chemotaxonomy 40 Clarionea; Clarionia 71 affinis 127 atacamensis 106 carthamoides 113 var. crispa 113 caulescens 144 macrocephala 90 magellanica 130 oa ce 113 nana cae ee 121 pilifera 110 polycephala 76 pungens 90 recurvata 149 spathulata 116 spectabilis 113 variabilis 121 virens var. humilis 144 * Accepted names are in bold face. Cytology 36, 38, 39 Distribution 5, 20, 30 Drozia 71 dicephala 90 Generic relationships 10 Heteranthus 71 History of the genus 7 Homanthis; Homoeanthus; Homo- 7 echinulatus 150 gayanus 124 humilis lll linearis 146 lyratus 124 magellanicus 119 var. lactucoides 119 tricep variabilis 121 viscosus 116 162 Introduction 3 Isanthus 71 Key to Nassauviinae lea! Key to species of Perezia 62 Leucheria fasciata 90 Literature 157 Morphology 14, 19 Numerical on ot 5D Palynolo 3 Perdicium heehee 119 magellanicum 129 acanthoides 76 aletes 79 aracensis 90 pues 106 beckii Stee 74, 132 calophylla 73, 131 capito 124 carduncelloides 73, 98 carthamoides 7, 113 5 136 ar. amplibracteata 136 conaicensis coriacea 96 cubaetensis 82 do: a elongata flavescens 150 foliosa 96 fonkii 75, 126 fosbergii 91 glandulosa 156 glomerata 76 va lactucoides 74, subsp. lactucoides 119 subsp. palustris 120 laevis lagascae 129 lanigera 156 laurifolia 102 linearis 73, 146 var. humilis 111 lyrata 74, 75, 124 magellanica 75, 129 mandonii 73, 74, 102 megalantha 75, 135 multicapitata 113 multiflora 73, 75, 76 subsp. multiflora 76 subsp. sonchifolia 76, 79 nitidifolia 1 nivalis 136 nutans 73, 88 obtusisquama 91 patagonica 150 ar. a 150 pectinata 150 Pedicularidifolia 15, 121 var. parvifolia 121 pilifera 74, 110 var. eget acs lll pristiphyllus 144 pungens 73, 90 var. cernua 90 purpurata 73, on 75, 106 pygmaea 74, 1 recurvata 73, io var. sessilis 150 reflexa 150 scapellifolia 96 var. cuhisetensis 82 ar. squarrosa 81, 82 stubels 90 INDEX 163 sublyrata 73, 99 var. pel 99 triceps 150 violacea 136 Proustia sect. Thelecarpaea 71 Scolymanthus 71 Species groups 5, 61 Stenophyllum 71 Taxonomic treatments 71 CONTRIBUTIONS FROM THE GRAY HERBARIUM OF HARVARD UNIVERSITY Edited by Reed C. Rollins and Robert C. Foster NO. CC THE CLASSIFICATION OF THE CYATHEACEAE By Rolla Tryon A MONOGRAPH OF THE FERN GENUS ERIOSORUS By Alice F. Tryon A REVISION OF THE GENUS MENKEA By Elizabeth A. Shaw NOTES ON STREPTANTHUS AND ERYSIMUM (CRUCIFERAE) By Reed C. Rollins Published by THE GRAY HERBARIUM OF HARVARD UNIVERSITY CAMBRIDGE, MASS., U. S. A. August 1, 1970 CONTRIBUTIONS. FROM THE GRAY HERBARIUM OF HARVARD UNIVERSITY Edited by Reed C. Rollins and Robert C. Foster NO. CC THE CLASSIFICATION OF THE CYATHEACEAE By Rolla Tryon A MONOGRAPH OF THE FERN GENUS ERIOSORUS : ~ By * i Alice F. Tryon A REVISION OF THE GENUS MENKEA By. Elizabeth A. Shaw NOTES ON STREPTANTHUS AND ERYSIMUM (CRUCIFERAE) Missoun! BaraNicaL ‘Reed C. Rollins vais nus? Bae | , | - Published by _ THE GRAY HERBARIUM OF HARVARD ‘UNIVERSITY , CAMBRIDGE, MASS., U, SAL oy, 1970_ THE CLASSIFICATION OF THE CYATHEACEAE RoLLA TRYON The Cyatheaceae is a moderate-sized family of about 650 species nearly equally divided between the neotropics and the paleotropics. The greatest number of species is found in the relatively cool and more or less constantly moist zones of tropical mountains. This feature may be seen in Fig. 1, where, within the distribution of the family in America, the areas of high concentra- tions of species correlate with the principal areas of cloud forest and montane forest. I am not including the members of the Dicksoniaceae within the Cyatheaceae as Holttum and Sen (1961) have recently done. While appreciating the characters that they have brought to the classification, I believe that more information is needed before the evolutionary lines in the Dicksonioid-Cyatheoid alliance can clearly be traced, and the family (or families ) recognized with assurance. There is, for example, some evidence which suggests that Lophosoria and Metaxya may be closer to the Dicksoniaceae than to the scaly Cyatheaceae. It is the classification of the scaly members of the Cyatheaceae which is my present concern and I have left in abeyance the problems raised by the Dicksonioid genera. I am tentatively following Christensen (1938) in recog- nizing the Cyatheaceae as including those genera that have a dorsal sorus. A few years ago I began a systematic study of the American Cyatheaceae and this paper is the first report of the work. I recog- nize eight genera in the family, one of them new and the others, except for the monotypic Lophosoria and Metaxya, variously en- larged or remodeled and mostly redefined on the basis of new characters. My initial studies were directed toward the evolution- ary developments in the family and the recognition of evolutionary groups which could form the basis of a generic classification. This survey indicated that there was greater morphological diversity among the American members of the family than among those of the Old World. For this reason, it was not possible to integrate the American species into the classification of Holttum (1963, 1964, 1965) which was developed principally on the basis of paleotropical species. The six main groups of the squamate species have been recog- 4 ROLLA TRYON nized as genera on the basis of the evidence that each is a major evolutionary line. Some of these genera are more distinctive and better defined than others, and some have more evolutionary inno- vations than others. There is no certain guide for the recognition of a group of species as a genus and I have chosen to admit to generic status only groups with substantial evolutionary qualifica- tions, either in distinctiveness or in extensive speciation. The more distinctive genera need not have a large number of species while those that have many species may be less distinctive. Fic. 1. Map of the distribution of Cyatheaceae in America and (in black) the areas of high concentrations of s cies: Hispaniola and Jamaica, 40 species; Costa Rica, 45 species; Andes, 125 species; southeastern Brazil, 40 species. THE CLASSIFICATION OF THE CYATHEACEAE 5 The present classification is based on a study of about 275 American species and about 230 species of the Old World. Ap- proximately 75 per cent of the known species, from all parts of the range of the family and including species of all proposed groups, has been examined. Confidence in the classification has devel- oped since its inception, as it has been brought into ever sharper focus by the incorporation of data from additional species and additional characters. An unsatisfactory classification has persisted in the Cyatheaceae for a longer time than in any other of the large groups of ferns. There is no purpose in a historical discussion of the futile efforts to classify the family. It is sufficient to point out that prior to the work of DeWolf (1953) and of Holttum (1957, 1963), no progress was made toward the development of a realistic classification based on evolutionary developments in the family. It is true that some small segregate genera were proposed earlier that now can be recognized as natural groups, but these proposals (and others that lacked merit) did not improve the classification of the large and heterogeneous assemblage that remained. The vital clue to the classification of the family was discovered by DeWolf (1953) in his studies of the petiole scales of paleo- tropical species, where he brought out the difference between “setiferous” (conform) and “flabelloid” (marginate) scale types. These studies were suggested by Holttum, who later (1957, 1963 ) successfully used the petiole scales over a very wide range of species in developing the classification of his inclusive genus Cyathea. In his classification the subgenera Cyathea and Sphaeropteris were based on the “flabelloid” and the “setiferous scales respectively. Holttum’s several papers (see Literature Cited) have provided the first broad foundation for the modern classifica- tion of the family. My own intensive study of the American species has resulted in some taxonomic and evolutionary conclusions different from those of Holttum; this is probably inevitable as progress is made in the study of a large and complex group- Further attention to the morphology of the petiole scales has added to the diversity of scale types in the family and has provided the basis for the recognition of three principal evolutionary lines. The scale mor- phology, even when not wholly distinctive (for example, in 6 ROLLA TRYON Nephelea and Cnemidaria) has been an important aid in the recognition of tentative evolutionary groups which have then been confirmed by further study of other characters. CHARACTERS A wide range of characters has been studied during the course of this investigation, most of which have not been usable at the generic level. Some are significant for species or species-groups; others, especially those of the stem, have not been represented in a sufficient number of species. Characters of the stem deserve careful attention but many more collections must be made before their significance can be assessed. Among the characters employed in this paper, some require explanation and these are discussed in the following paragraphs. The petiole is sometimes smooth but more commonly, especially toward its base and on its abaxial side, it is variously roughened or spiny. A petiole that is pubescent sometimes becomes scabrous as the trichomes break off and leave a persistent base. In most species the petiole scales are borne on slight to very prominent projections of the petiole and these persist when the scale falls. When these projections are very low, the petiole is muricate; when they are larger but rounded and about as tall as broad, the petiole is tuberculate; when they are taller and tapering at the apex, they are called spines, and the petiole is aculeate. In most of the aculeate species, the spines have evidently evolved by a development of the tissues of the petiole beneath the scale. I call these corticinate spines (cortex + natus: born of the cortex of the petiole). These can readily be identified in suitable material because a complete scale is perched on top of the spine (Fig. 22). The scale is sometimes not clearly differentiated from the apex of the spine, suggesting that the apex may be partly formed from the base of the scale. There is a complete transition from species with a smooth petiole to those with large spines of the corticinate type. In other species the spines (Fig. 31) have evidently evolved by development of the body of the scale and the tissues of the petiole have not been involved in their formation. These are called squaminate spines (squama + natus: born of a scale). This kind of spine can be readily identified on suitable material because THE CLASSIFICATION OF THE CYATHEACEAE 7 some of the smaller spines will bear, on each side, the differenti- ated margin of the normal scale (Fig. 34). Rarely, an unmodified portion of the scale extends beyond the apex of the spine. There is a transition in Alsophila from species with normally developed scales to those with spinelike scales and to one species with squa- minate spines. The evidence for the origin of this type of spine from a petiole scale is discussed more fully under the genera Nephelea and Alsophila. It is sometimes necessary to refer to different parts of the petiole scales and to different kinds of scales. The body of the scale is considered to be the whole scale except for such processes (cilia, teeth, setae) as may be borne on the edge or at the apex. The edge of the scale is considered to consist of the single row of ultimate cells, or when cilia, teeth or setae are present, some- times an additional row of cells that may be related to those processes. The petiole scales of Sphaeropteris have all the cells of the body similar in shape and orientation (elongate with their long axis parallel to that of the scale) and usually in size and color (for example, Figs. 14-17). This kind of scale is called structurally conform or simply conform. In the other genera, the central cells of the petiole scales are also elongate and parallel to the long axis of the scale, but toward each edge the cells are different in size and orientation, and (usually) in shape and color (for example, Fig. 27). The central area of elongate cells then is called the central portion and the differentiated area (on each side) the margin. This kind of scale is called structurally marginate, or simply marginate. The margin may be broad or narrow and it may be well or poorly defined depending on the abruptness of the transition between the elongate cells of the central portion and the differentiated cells near the edge. In many species there is a minute indument on the surface of the petiole that consists of very small scales or trichomes. These are composed of only a few cells. The small scales of this indument are called squamulae and the small trichomes trichomidia. The indusium may completely surround the base of the recept- acle, or not, and it may be variously developed. Very small indusia that are attached to one part of the base of the receptacle are called scale-like. Moderately to well developed indusia that par- tially surround the base of the receptacle are called hemitelioid. 8 ROLLA TRYON Well developed indusia that completely surround the base of the receptacle are called cyatheoid if they are open at their apex, and sphaeropteroid if they are closed at their apex. EVOLUTION Among the squamate genera the characters of the petiole scales define three groups which I believe reflect the basic evolutionary lines: the genus Sphaeropteris with structurally conform petiole scales (Figs. 14-21), the genera Alsophila and Nephelea with structurally marginate petiole scales having dark apical setae (Figs. 23-30, 35-36), and the genera Trichipteris, Cyathea and Cnemidaria also with structurally marginate petiole scales but without apical setae (Figs. 39-41, 44-47). These three groups are evident in the phyletic chart (Fig. 2). Within Sphaeropteris, Alsophila and Nephelea, further evolu- tionary developments occur that involve a thickening of the petiole scales. In a number of species of Sphaeropteris of Malaysia and Polynesia, the scales are basally thickened and rather fleshy. These species were recognized as Cyathea subsection Sacropholis by Holttum (1963). A similar development is also evident in some species of Alsophila of the West Indies, especially in Alsophila Urbanii which has small scales definitely thickened and some- what fleshy. In other species of Sphaeropteris and Alsophila and in Nephelea the thickened petiole scales are hard and rigid. In Sphaeropteris procera of New Guinea some of the scales are quite modified and spine-like; and in Alsophila auriculata of Madagascar and in Nephelea the thickened and rigid scales form a transition from the normal scales on the petiole to the petiolar spines. In a general way, it is possible to postulate an adaptive basis for the origin of scales and their structural differentiation. The arborescent habit elevates the apex of the stem with its crown of large leaves far above the root system. This must create prob- lems in water relations that require some compensating adapta- tions. Any evolutionary development that would aid the roots and tall stem in providing water to the apex would contribute toward the solution of this problem. A dense investment of scaly indument could provide a better means for the absorption of water in the form of fog or rain than an investment of trichomes. The effective- THE CLASSIFICATION OF THE CYATHEACEAE 9 ness of the scales in water absorption could be improved by differ- ent orientations of the scales (Figs. 3, 4) and differences in their cellular construction. This concept provides an evolutionary rationale for the development and differentiation of the petiole scales. It also provides a basis for the conclusion that the develop- ments in the petiole scales have been basic to the establishment of the major evolutionary lines in the squamate group. I adopt the view that the genera with scales have evolved from ancestors having an indument wholly of trichomes. There are a few species among American Sphaeropteris that have petiole scales quite undifferentiated in cellular structure and two of these also have the scales intergrading to trichomes. In these species, Sphaeropteris macarenensis and S. mollicula, there are long tri- chomes on the petiole as well as long narrow scales that vary from two to many cells broad (Figs. 5-9). The cells of the scales are similar in size and proportion to those of the trichomes (compare Fig. 5 with 6 and 7). The base of some of the narrow scales is uniseriate (stipitate) (Fig. 6). The structure of these suggests that the first stage in the development of a scale has been a pluri- seriate development above the base of a trichome. I consider that Sphaeropteris macarenensis and S. mollicula are primitive among the scaly species in respect to both their undifferentiated petiole scales and their petiole indument that shows the transition from trichomes to scales. The origin of the indusium in the Cyatheaceae, and its evolu- tionary significance, has been subject to considerable disagree- ment. Bower (1926, Chapter 33) considered the exindusiate condition of the sorus to be primitive and the indusium to be a new structure which evolved later. Holttum and Sen (1961) and Sen (1964) interpret the indusium as homologous with that of Dicksonia, marginal in origin and the hemitelioid indusium as primitive. I believe that evidence from three sources supports Bower's interpretation that the indusium has originated from a laminar scale attached to the base of the receptacle. In the exindusiate species Trichipteris armata, there is usually a small scale closely associated with the receptacle but not attached to it (Riba, 1969). This scale is borne, slightly toward the midvein, on the vein that bears the receptacle. There is a small group of species in Malaysia and Polynesia (Cyathea subsection Fourniera, Holttum 1963, 1964) that has thin scales investing the sorus, 10 ROLLA TRYON arising from the base of the receptacle. Finally, there are some species, for example Cyathea Tuerckheimii, in which a sphaerop- teroid indusium bears an apical squamoid development ( Fig. 10). This evidence strongly suggests an intimate relation between a laminar scale and an indusium, which I interpret to mean that the indusium is of squamate origin and that the indusiate sorus has been derived from the exindusiate sorus. The exindusiate condi- tion of Sphaeropteris macarenensis and S. mollicula is consistent with the conclusion, drawn from their petiole indument, that they are species with primitive characters. Sphaeropteris macarenensis and S. mollicula are different in some characters of the sorus from other scaly species. These characters are their slightly to moderately elevated receptacle, relatively few sporangia in a sorus and nearly globose sporangium capsule. In these soral characters the two species are rather similar to Lophosoria as indicated in Table 1. The comparisons presented there include characters of the petiole indument, the sorus and indusium and also the contrasting characters of a scaly indusiate species. It is reasonable to consider the wholly pubescent Lopho- soria as representing a lower evolutionary level than the scaly genera of the family and the similarities in soral characters be- tween it and Sphaeropteris macarenensis and S. mollicula suggest that those species are also at a rather low evolutionary level. These considerations, summarized in Table 1, are all consistent with the conclusion that Sphaeropteris macarenensis and S. mol- licula are species with primitive characters and are the most primitive of the living scaly species. Thus Sphaeropteris is taken as the most primitive of the scaly genera. The phyletic relations of the genera are presented in Fig. 2. Lophosoria and Metaxya are placed apart in order to avoid the implication that either is directly ancestral to the group of scaly genera. Sphaeropteris is considered to have been derived from an ancestral line on an evolutionary level similar to that of Lopho- soria but not necessarily one that would be congeneric with it. The first development of an indusium occurred in some species of Sphaeropteris and in one line setae were developed at the apex (and usually along the edge) of the petiole scales. A major evolu- tionary line has developed from each of the petiole scale types in Sphaeropteris. The setate type has given rise to Alsophila by the differentiation of the margin on the petiole scale and then to Petiole indument Receptacle Number of sporangia in a sorus Sporangium capsule Indusium TABLE | CHARACTERS OF FOUR SPECIES OF CYATHEACEAE Lophosoria quadripinnata trichomes only low ca, 6-12 asymmetrically globose none Sphaeropteris Sphaeropteris macarenensis mollicula trichomes intergrading to undifferentiated scales slightly moderately elevated elevated ca, 8-12 ca. 9-15 asymmetrically asymmetrically globose none none Cyathea arborea Broad, differentiated scales strongly elevated ca, 25-50 asymmetrically e Fei: SS Sie cyatheoid AVAOVAHLVAO AHL JO NOILVOMISSVTIO AHL 12 ROLLA TRYON Nephelea by the development of squaminate spines on the petiole. Some species of Alsophila are exindusiate, indicating that the indusium evidently originated at least once in this line. An ex- indusiate group in Sphaeropteris with petiole scales lacking dark setae has given rise to the genera Trichipteris, Cyathea and Cnemidaria, again by a differentiation of the margin on the scale. The exindusiate Trichipteris gave rise to Cyathea by an independ- ent development of the indusium. Cnemidaria has evolved in lamina reduction and vein modification especially; it was probably derived from species of Cyathea in which the indusium was only partially developed. This phyletic scheme provides a framework within which other evolutionary developments can be placed and provides an indication of the general evolutionary level of the genera. NEPHELEA : CNEMIDARTA . CYATHEA scale body structurally marginate ALSOPHILA 32 TRICHIPTERIS scales i scales not setate oe setate SPHAEROPTERIS scale body structurally conform scales present scales absent LOPHOSORIA METAXYA Fic. 2. Phyletic chart of Cyatheaceae. THE CLASSIFICATION OF THE CYATHEACEAE 13 aie v4 : 9 1S; — R,4 i — AS. Gs. 3-13. CyaTHEAcEAE. Fics. 3-4. Longitudinal sections of the stem apex, the older croziers removed, the Lata are very tightly packed and the lines indicate sep the general orientation and we not the individual scales: 3, Small, patent scales 0 itens, on x 1/2, GH, 4, Larger, imbricate scales of Cyathea io conspersa, Tryon & Tryo : 1/2, GH. Fries. 5-9. Petiole indument of Sphaeropterts racarenensis, Schultes & Cabrera 13368, all X 60, A:5, s ion of trichome. 6, 1 porti £ scale two cells wide. 7, Central portion of narrow scale. 8, ex of Seaie in” Pi , Central p of a broad scale. Fic Indusia of Cyathea mii, normal globose indusium (left) and indusium with scale developed apically (right), Steyermark 46 8, US. F1 1-13. Lower epidermis with stomata Gs. 3 ophosoria quadripinnata, ag stomate near vein (left), others are sunken, an 92, X 180, GH. 12, Metaxya rostrata, Kramer et al. 5651, X 90, GH. 13, eons. dissimilis, Wurdack 34154, X 90, NY. 14 ROLLA TRYON SPECIES I am providing lists of the species under broad geographic headings, as a matter of information and, in many cases, to provide a correct name under the new classification. I have accepted the taxonomy of Holttum for the species of Asia, Malaysia, Australasia and the Pacific, of Tardieu-Blot (1951) for those of Madagascar and (1953) central Africa, and of other current authors for those of the remainder of Africa. I have included only those American species that I believe to be adequately known. They are listed only under the geographic region from which the type originated because, in some cases, their total range is uncertain. In addition to the synonyms required for the new combinations and new names, others are given when they seem useful. Tax- onomic synonyms and the basionyms of nomina nova are also given separately, in brackets, alphabetically by the epithet with reference to the correct name. ACKNOWLEDGEMENTS eg study has been supported by de poe Aajergts rons (GB ) and without this financial aid m of the work could not sei been completed. I am especially in indebted *e Gerald 1. ‘Gattoay, Dr. amén Riba and Dr. Alice F. Tryon for aid in collecting and preparin a and for perceptive discussions on the problems of classification an evolution. Dr. Ramén Ferreyra, Dr. Bassett Maguire, Dr. Ben parre, ie : : . Carm technical assistance and some speci aks es. I am also indebted to the officers in charge of the heesoabih who have cordially made their facilities i de loans of m tani jum, Copenhagen; Field we dasa of Natural History; Royal Botanic Gardens, t, Naturhistoriska cata Stockholm; New York Botanical sirkiinees Garden; ite de Phanérogamie, Muséum National d’Histoire Natur- elle, Paris; and Department of Botany, Smithsonian Institution. KEY TO GENERA b. Lamina decompound, be dame seen ob th segments scarely modified, stomates with two subsidiary cells, one on the side of each THE CLASSIFICATION OF THE CYATHEACEAE 15 guard cell, sunken between the veins, gear near sags iO pe bh). sporangium sta : with six rows of cells, ee oria. amina l-pinnate, costa grooved, margin a pinnae c ea nous, stomates with tice subsidiary cells, one on the side of each guard cell and a third on the side of the smaller one, be eegenn ( Fig. me} ene chit stalk with four rows of cells, n=ca. 95 .......... axyd. . Stem and petioles with scales, trichomes present or absent on . bl ps sone’ ees one subsidiary cell, partially enclosing both guard cells, or sometimes with a second one partially enclosing the other, superficial (Fig. 13), receptacle elevated (rarely ney so), capsule of the sporan- gium small (ca. 0.15-0.2, rarely to 0.3 mm ong), sporangium stalk with four rows of on n= 9. C: c. Petiole scales structurally co nform (for example Figs, 14-17), the cells of the body similar in orientation, shape, and ( unaly? in size and onder: 3... Seeds. hi buad sieeus Dike phaeropteris. . Petiole scales ey aoe pose (for example ef oe 23 Si. ye with a narrow to broad margin of cells as in orientation, size, and (usually) in ehh and ren ie those of ral portion. d. d. Mo scales piaholy me of them) with a dark (ver wane gies lored) apical seta ioe example, Fig. 24), similar setae s ane borne on the body of the scale (Fig. 37), or on its dpe e. e. Petiole lacking nee smooth to tuberculate, or with corticinate > Q side) more or less appressed, attached at a thickened sid or usually at one point of a pseudopeltate or peltate ~ eee ne = RRO eS re we ‘0 e. Petiole with squaminate sl many large, black, mostly obturbinate with a slender x (Fig. 31), (tig. 30). spines bear Sai Q ae] o og o fa) n”n So DB g S oO “as 5 aa n”n a oo x) z 3 ral Ld g cy a o S =r) ee o a & = oe vy —_. aa n f. Veins ais (tafely some branch and rejoin), in lobed or pinnati- fid segments the basal vein on each side ‘extending above the base of the sinus (Figs. 42-43), costa pubescent above (rarely glabrous), minute indument or the petiole, when present, of squamulae or Se of patent trichomidia. g. g- Indusium abeent 0. - seg reed enter ncete: g. Indusium tae rarely scale-li phaero hoe * Veins forming areolae along the costa sometimes yon / (Figs. 49-50 ‘i or all free and then in lobed or ~ segments ase 0 16 ROLLA TRYON 1. LopHosoria pruinata (Sw.) Kze. (Polypodium pruinatum Sw.) = Lophosoria quadri- pinnata (Gmel.) C. Chr. I cannot find that the separate publication of Presl’s “Gefiiss- biindel” has been accurately dated and therefore accept the date on its title page. Stearn (1954) gives dates for other publications of Presl. Liebmann clearly indicated the type of his genus: “Typus denne Slaegt er Alsophila pruinata Kaulf.”, although he made no combination for it under Trichosorus. At that time a type had not been selected from among the three species originally included in Lophosoria by Presl so that although both generic names have the same type, Liebmann’s is not superfluous. An American genus of one species, Lophosoria quadripinnata (Gmel.) C. Chr., in the Greater Antilles, Mexico and Central America, Andean South America, south to Bolivia; southern Chile and Juan Fernandez Islands. Lophosoria (Fig. 11) is a very dis- tinctive genus and only a selection of its characters is given in the key to genera. Some others are mentioned in the discussion of evolution in the family. A chromosome number of n=65 is re- ported by Walker (1966). 2. METAXYA ph sub Trichopteris, 1834, nom. nud.; Pres], Tent. Pterid. 246. 1836, nom. nud.; . Lond. Jour. Bot. 1:668. 1842). Type: Amphidesmium blechnoides (Hook.) J. Sm. (Alsophila blechnoides Hook.) = Metaxya rostrata (HBK.) Presl. Schott’s publication of Amphidesmium is clearly invalid, al- though it was generdally accepted by his contemporaries. Presl adopted the genus but supplied so brief a diagnosis that his pub- lication of its name can also be considered to be invalid. If one chooses to accept it as valid, however, then it is important to note that John Smith treated Amphidesmium as a synonym of Metaxya THE CLASSIFICATION OF THE CYATHEACEAE 17 a few years later. The name was certainly validly published by John Smith in 1866 and may have been validated earlier. An American genus of one species, Metaxya rostrata, (Fig. 12) in the Lesser Antilles, Central America, northern South America and the Andes south to Bolivia. Metaxya, like Lophosoria, is a very distinctive genus and only a few of its characters are men- tioned in the key to genera. A chromosome number of n=ca. 95 is reported by Roy and Holttum (1965). 3.. SPHAEROPTERIS Sphaeropteris Bernh. Schrad. Jour. Bot. 1800 (2): 122. 1801, not Wall. 1830 (=Peranema). Type: Sphaeropteris medullaris (Forst.) Bernh. (Poly- podium medullare Forst). Schizocaena J. Sm. in Hook. Gen. Fil. t. 2. 1838. Type: Schizocaena brunonis J. Sm. = Sp op) STyOD Eatoniopteris Bomm. Bull. Soc. Bot. France 20: xix. 1873. Lectotype: Cyathea insignis D. C. Eaton (Bommer made no combinations for the names of the 19 species he placed in his new genus) = Sphaeropteris insignis (D. C. Eaton) Tryon. i Fourniera Bomm. Bull. Soc. Bot, France 20: xix. 1873. Type: Fourniera novaecaledoniae (Mett.) Bomm. lsophila novae-caledoniae Mett.) = phaeropt doniae ( tae may be borne at the indument of the petiole, when present, of trichomidia and (or) of squamulae; costa pubescent above or rarely glabrous; veins free, in lobed or pinnatifid segments basal vein on each side extending above the bas indusium absent, or present and hemitelioid to sphaeropteroid, or formed of several closely investing scales. Sphaeropteris (Figs. 5-9, 14-21) is a genus of about 120 species, some 20 of them American and the remainder distributed from India and southeastern Asia to New Zealand, the Marquesas and Pitcairn Island. In the Old World the genus is exactly Cyathea subgenus Sphaeropteris of Holttum (1963, 1964, 1965). This sub- genus was classified by Holttum as follows: section Sphaeropteris with subsection Sphaeropteris and subsection Fourniera, and sec- tion Schizocaena with subsection Schizocaena and subsection Sacropholis. In America there are several species, for example, Sphaeropteris insignis, S. Brunei and S. horrida (Fig. 19) that have 18 ROLLA TRYON the petiole scales very like those of Sphaeropteris medullaris, S. concinna (Figs. 20, 21) and other related species of Holttum’s subsection Sphaeropteris. Other American species do not exhibit relations outside of the western hemisphere. These are represented by a number of rather isolated species or distinctive species- groups that are sufficiently diverse so that, at this time, I hesitate to accommodate them (perhaps as a coordinate section) in Holt- tum’s classification. A chromosome number of n—69 was reported by Brownlie (1961) for Sphaeropteris medullaris (as Cyathea medullaris ). The genus Sphaeropteris is characterized by the petiole scales that are structurally conform (undifferentiated or poorly differen- tiated) in their cellular construction. In most species the cells of the scale (except for processes such as cilia, teeth or dark setae that may be borne on the edge or apex) are nearly alike in their size, color, thickness of walls, their elongate shape and their orientation parallel to the long axis of the scale. Sometimes the cells near the edge are smaller than those at the center, or have thinner walls, or may be much lighter in color. These variations, as well as the various processes that may be borne on the edge or apex, are illustrated in Figs. 14-17 and 20. They are all developed on a basically uniform cellular pattern of the body of the scale. A few species, such as Sphaeropteris hirsuta and S. marginalis, have some petiole scales slightly marginate with the margin weak- ly modified and very narrow; others, such as Sphaeropteris senilis and S. stigmosa, have areas of slightly modified cells occurring at intervals along the margin. These examples of species with ten- dencies toward a marginate scale nearly provide a connection with Trichipteris in which a few species have slightly marginate scales. Some species, including the most primitive ones, Sphaeropteris macarenensis and S. mollicula, lack a dark apical seta on the petiole scale. The others have a dark seta and these include most of the species of Sphaeropteris of the paleotropics. However, in Sphaeropteris albifrons the seta is nearly concolorous with the brownish scale body; in S. vittata it is very small; in S. discophora there are two small dark setae at the apex and in S. agatheti there are several setulae. The scales of the species treated by Holttum as subsection Sacropholis are much enlarged basally and may be at least 15 cells THE CLASSIFICATION OF THE CYATHEACEAE 19 thick. The relation to other species of Sphaeropteris is clearly indicated by their conform cellular structure, which is most easily seen beyond the thickened basal portion. Sphaeropteris procera of New Guinea is unique in the genus in having some of the larger scales rather spine-like. These are rigid and subterete basally, while toward the apex the scale body is like that of the smaller scales. They become variously broken with age and are not persistent as definite spines. The primitive type of indument of the petiole of Sphaeropteris macarenensis and S. mollicula, which is partly composed of long Fics. 14-21. SPHAEROPTERIS, portions Schultes & Cabrera 13368a, GH. 15, Sphaeroptert marginalis, Maguire 24544, A. 17, S. myosurot Steyermark 91129, US. 19, Apex, 5. horrida, 0 concinna, Brass 3724, GH. 21, Apex, S. concinna, Brass 3124, GH. of petiole scales, all X 30: 14, S. mollicula, is sp. nov., Schultes 3389, GH. 16, S. des, Deam 482, GH. 18, x, S. senilts. s , 20 ROLLA TRYON trichomes, has been discussed in the remarks on evolution. It would be of interest to know whether similar trichomes occur on the stem of these species. I am not able to determine this in the materials available because the persistent petiole bases are so closely crowded that the small areas of stem surface cannot be distinguished with certainty. WEST INDIES Sphaeropteris insignis (D. C. Eaton) Tryon, bron nov., Saree insignis D. C, Eaton, Mem. Amer. Acad. n.s. 8:215. MEXICO AND CENTRAL AMERICA boO Sphaeropteris Brunei ‘naglead Loe comb. nov., Cyathea Brunei Christ, Bull. Herb. Boiss. II, 4:947, S. myosuroides (Licbm:) ‘Tryon, comb. nov., Alsophila myosuroides Liebm. Vid. Selsk. Skr. V, 1:286. 1849. S. horrida (Liebm. ) Tryon, comb. nov., Cibotium horridum Liebm. Vid. Selsk. Skr. V, 1:279. 1849, Cyathea princeps E. Mayer, Gartenfl. 17:10. 1868. [Cyathea princeps= Sphaeropteris horrida]. SOUTH AMERICA Be eng y aterrima (Hook.) Tryon, comb. nov., Alsophila aterrima Hook. Syn. Fil. 38. 1866 [Cyathea fe mera ee quindiuensis]. S. elongata (Hook.) Tryon, comb. nov. , Alsophila elongata Hook. Sp. Fil. ‘Ss. Gardneri (Hook.) Tryon, comb. nov., Cyathea Gardneri Hook. Sp. Fil. 2 | be Ss: ‘cihhiece (KI.) Tryon, comb. nov. , Alsophila gibbosa K\. Linnaea 18:542. ° 1844. S. hirsuta (Desv.) Tryon, comb. nov., Polypodium hirsutum Desv. Ges. / Naturf. Freunde Berl. Mag. 5:317. 1811, " Hemitelia hirsuta (Desv.) Weath. | phones lechria=Sphaeropteris dagen acarenensis (Alston) Tryon, comb. , Dryopteris macarenensis - png Mutisia 7:5. 1952, Alsop ila s macarenensi "(Alston ) Tryon, Alsophila ' ina a a (Presl) Tryon, ae Hemitelia macrocarpa Presl, Gefiindel 3 Stipes ies Farrn 41. 1847 pecan: from Abhand]. béhm. Ges. V, 5:352. 1848). S. marginalis (Kl.) Tryon, comb. nov., Alsophila marginalis Kl. Linnaea 18:542. 1844. Feo mollicula (Maxon) Tryon, comb. nov., Alsophila mollicula Maxon, Jour. - Arb. 27:440. 1946, Alsophila lechria Tryon : quindiuensis (Karst. ) Tryon, comb. nov., ‘Cyathea quindiuensis Karst. ° Linnaea 28:454. 1857, Cyathea crassipe. s Sod. (Aoi scopulina=Sphaero ropteris macarenensis]. a senilis (Kl.) Tryon, comb. nov., Alsophila senilis Kl. Linnaea 20:442. ° 1 S. stigmosa (Desv.) Tryon, comb. nov., Hemitelia stigmosa Desv. Mém. ~ Soc. Linn. Paris 6:321, 1827. THE CLASSIFICATION OF THE CYATHEACEAE 21 ASIA Sphaeropteris albosetacea (Bedd.) Tryon, comb. nov., Alsophila albo- pete rapa Suppl. Ferns So. India Brit. India 2. 1876, Cyathea albosetacea Bedd.) C S. raat fa (Hook.) T comb, nov., Alsophila brunoniana Hook. Sp. Fil. 1:52. 1844, Cyathea aaleae (Hook. ) Clarke & Baker Cyathea Seay erouterss glauc S. crinita (Hook.) Tryon, comb. no Alsophila crinita Hook. Icon. PI. 7: t. 671. 1844, and a. Fil. 1:54. 1844, Cathes crinita (Hook.) Copel. S. glauca (BI.) Tryon, comb. nov., Chnoophora glauca Bl. Enum. Pl. Jav. 243. 1828, Cyathea contaminans (Hook. opel. S. hainanensis (Ching) Tryon, comb. nov., Cyathea hainanensis Ching, Acta Phytotax. Sinica 8: a 1959. / §. lepifera (Hook.) Tryon, comb. nov. iS 2 ae lepifera Hook. Sp. Fil. 1: 54. 1844, agg lepers | aaa Le . Mertensiana (Kze.) T nea 8 , Alsophila Mertensiana Kze. Bot. Zeit. 6:586. 1848, Cyithes Mlertonsiéas (Kae. ) Copel. MALAYSIA Sphaeropteris aciculosa oe } Tryon, comb. nov., Cyathea aciculosa Copel. Phil. Jour. Sci. 60:104. 193 S. aeneifolia (vAvR.) Tryon ea oe aeneifolia vAvR. Nova Guinea 14:3. 1924, Cyathea aie ‘(vAVR. ) Copel. S. agatheti ( Holtt.) Tryon, comb. nov., Cyathea agatheti Holtt. Kew Bull. 16:51, S. albidosquamata (Rosenst.) Tryon, comb. nov., Cyathea ri mata Rosenst. Fedde Repert. 12:525. 1913. Placed by Holttum (1963) among species that I treat as Alsophila, but I believe that it ine in Sphaeropteris. S. alternans (Hook.) Tryon, comb. = Hemitelia alternans Hook. Icon. Pl. t. 622. 1844, Cyathea alternans (Hoo Kk.) Bedd. S. angiensis reeot ae Tryon, comb. n Alsophila angiensis Gepp, in cite Dutch N. W. New Guinea 69. "1917, Cyathea angiensis (Gepp) gustipinna eas ) Tryon, comb. nov., Cyathea angustipinna Holtt. Kew Bull 16:52. . arthropoda ica ea) GS comb, nov., Cyathea arthropoda Copel. Phil. Jour. eo 6 (Bot. oe 134. 1 S. assimilis (Hook.) Tryon, comb. nov., Cyathea assimilis Hook. Syn. Fil. 24. 1865. ig s. gen miro) Tryon, comb. nov., Cyathea atrospinosa Holtt. Kew Bull. 16:52. ae’: S. atrox (C. Chr. ) Tryon, comb. nov., Cyathea atrox C. Chr. Brittonia 2:275. 1937. ee S. auriculifera (Copel. ) ie comb. nov., Cyathea auriculifera Copel. si oe Sci. 6 phlnerydie 364. 1911. Poy binuangensis (vAvR. ) Tryon, comb nov., Cyathea binuangensis vAv Bull Jard. Bot. Buitenz. III, 2:136. 1920. 2 S. capitata (Copel.) Tryon, comb. nov., Cyathea capitata Copel. Phil. our. Sci. 12 (Bot.): 49. 1917. : s. Carri (Hot Tryon, comb. nov., Cyathea Carrii Holtt. Kew Bull. 16:53. 1962. 22 ROLLA TRYON S. celebica (BI.) Tryon, comb. nov., Cyathea celebica Bl. Enum. Pl. Jav. 245.1 S. concinna (Baker) Tryon, comb. nov., fey cae ee Baker, Syn. Fil. a 2, 459. 1874, Cyathea sangirensis (Christ) C [Cyathea Be eat aohadoees glauca]. S. Curranii Pg me Tryon, comb. nov., Cyathea Curranii Copel. Phil. Jour. Sci. 3:356. 1909. ag bie oie ot aeropteris parvifolia]. S. discophora (Holtt.) Tryon, comb. nov., Cyathea discophora Holtt. Kew Bull. 16:54. 1962. S. elliptica (Copel. ) greet comb. nov., Cyathea elliptica Copel. Phil. lowes a age 12 (Bot. ): ri (Copel. ) tye mb. no N:, cinta Elmeri Copel. Leafl. Phil. faa. 2: rire 1908, Cyathea Elmeri (Copel. )C S. fugax ax (vAVR. 3 Aes comb. nov. Fe haities iid vAvR. Bull. Jard. Bot. Buitenz. II, 7:8. S. fusca (Bakes) ica. comb. nov., Cyathea fusca Baker, in Beccari, oo = ol. Ss. a ( ee oe (supra). Ss. inaequalis (Holtt.) Tryon, comb. nov., Cyathea inaequalis Holtt. Kew Bull. S. al es n (Holt. Tryon, comb. nov., Cyathea insularum Holtt. Kew Bull. 16:57. 1 S. integra Gs a ) Tryon, comb. nov., Cyathea integra J.Sm. Icon. PI. t. 638. 1844, S$. Ledermannii (Brause) Tryon, comb. nov., Hayles Ledermannii ere Bot. Jahrb. 56:60. 1920, oe pian ag S. lepifera (Hook.) Tryon (supra). sage ge tricha (Chri st) —— comb. nov., Cyathea leucotricha Christ, 1 S. lunulata( Forst. ) Ro Ay mb. Polypodium ie Forst. Fl. Ins. Aust. Prod. 83. 1786, Couthes vi (Forst.) C et macrophylla—Sphaeropteris Ledermannii]. magna (Copel. } Pe a comb. nov., Cyathea magna zie Univ. Calif. Publ. = Bar 218. S. ata (ras as Tryon, comb. nov., Alsophila eens Brause, Bot. Jahrb, 36:6 3. 1920, Cyathea marginata Sanne Pons S . me Phil. Jour. Sci. 12 (Bot.): 54. 1917. S. moluccana ( Desv. Tryon, comb., nov., Cyathea moluccana Desv. Mem. Soc. Linn. Paris 6:322. 1827. S. Moseleyi (Baker) bm comb, nov., Cyathea Moseleyi Baker, Jour. ee Soc. Bot. 15:104. 1876. obliqua lag pee ays, comb. nov., Cyathea obliqua Copel. Leafl. Phil Bot. 4:1150. 1 S. obscura (Beda.) ne n, comb. nov. Soa ag obscura Bedd. Jour. Bot. 25:321. 1887, Cyathea obscura au bane i yo idley) T. Mal. Br. Roy. As. Soc. 6:19. 1928 28, Cyathea aie Ss. — (Holt. ) Tryon, comb. nov., Cyathea oar Holtt. Kew Bull. 1 THE CLASSIFICATION OF THE CYATHEACEAE 23 S. persquamulifera (vAvR.) Tryon, comb. nov., Cyathea contaminans v, persquamulifera vAvR. Bull. Jard. Bot. Buitenz. I, 28:13. 1918, Cyathea persquamulifera (vAvR.) Domin S. philippinensis (Baker) Tryon, comb. nov., Cyathea philippinensis Baker, Ann. Bot. 5:186. 1891. S. pilulifera (Copel. ) EP bs comb. nov., Cyathea pilulifera Copel. Univ. Calif. Publ. Bot. 18:219. S. polypoda ae ker ) inn n, comb, Bako Cyathea polypoda Baker, Trans. Te a | d. II (Bot.) 4:250 ocera (Branse) Tryon, pitt nov., Cyathea procera Brause, Bot. Jab 56. 50. seat (Copel. ) Tryon, comb. nov., Cyathea pulcherrima Copel. Univ "Calif. Publ. Bot. 18:219. 1942. obinsonii (Copel. ) oi comb. nov., Cyathea Robinsonii Copel. Phil. Jour. Sci. 6 (Bat): 145. 1911. S. seacygenepe (Brause) Tryon, comb. nov., Cyathea Rosenstockii Brause, Jahrb. 56:4 ~_. 5. | (as R.) Tryon, comb. nov., Cyathea runensis vAvR. Bull. Dépt. athea d. Néer. 18:1. 1908 ad thea sangrensisSphse eropteris concinna]. : ore shi tt.) Tryon, comb, nov., Cyathea Sarasinorum Holtt. N Kew Bull ‘16:6 S. senex aay ) Tryon, comb, nov., Cyathea senex vAvR. Bull. Jard. Bot. Buitenz. II, 16:4. 1914. S. setifera (Holtt.) Tryon, comb. nov., Cyathea setifera Holtt. Kew Bull. 16:62. 1962. S. si barra copes , Ri comb. nov., Cyathea sibuyanensis Copel. Leafl. Phil. Bot. 4:1150. 1 S. ic (BI.) Tryon mb. cal squamulata Bl. Enum, Pl. Jav. 243. 1828, Cuurhed pape be 1BL) C S. stipitipinnula (Holtt.) Tryon, comb. nov., Cyathea P die ions Holtt. Kew Bull. . 1962. a aa tC hrist ) id si comb. nov., Cyathea strigosa Christ, Ann. Jard. Bot. Buitenz. 15:84. 1 A Ss. aoa see Tryon, comb. nov., Cyathea suluensis Baker, Jour. Bot. 17:65. S. tenggerensis (Rosenst.) Tryon, comb. nov., Alsophila tenggerensis Rosenst. Medel. Rijksherb. 31:1. 1917, Cyathea tenggerensis (Rosenst. t.) Domi S. Teysmannii (Copel. ) LAS ins comb. nov., Cyathea Teysmannii Copel. Phil. Jour. Sci. 4 (Bot.): 51. : .) Tryon, c si i, Chee tomentosa Bl. Enum. Pl. Jav. 244. 1828, Cyathea tomentosa “BL. ) Zoll. & M ; opel.) Tryon, pp nov., Guathee tomentosissima Copel. Univ. Calif. Publ. Bot. 18:219. 1 5. trichodesma (Bedd.) Tryon, comb. n ace aes trichodesma Bedd. Jour. Bot. 25: 321. inate Cato richodesma (Be opel. é S. trichophora (Copel. ) bi aysed comb. ni ricpahes trichophora Copel. Phil. Jour. Sci. 6 Saige 363. 1 S. Lcicttage ope ) Lely saab, nov., Cyathea tripinnata Copel. Phil. our. Sci. 1, Suppl. : as tripinnatifida ( ate , Tryon, comb. nov., Cyathea tripinnatifida Roxb. c. Jour. Nat. Hist. 4:518. 1844. 24 ROLLA TRYON S. rrp ssapasien, Tryon, comb. nov., Cyathea verrucosa Holtt. Kew Bull. 16:63. Ss. Wallacel ee Tryon, comb. nov., Far yet Wallacei Kuhn, Linnaea 36: 153. baat , Cyathea Wallacei (Kuhn) Copel ri (Rosenst.) Tryon, comb. nov., Cyathea Werneri Rosenst. Fedde nape 5:34. 1908. Ss: Meese osie9 hace Tryon, comb. nov., Cyathea Womersleyi Holtt. ~~ = 16 962. aeeaee (Copel.) Tryon, comb. nov., Cyathea zamboangana Guaes “Phil Jour. Sci. 30:325. 1926. AUSTRALIA AND PACIFIC Sphaeropteris aciculosa (Copel.) Tryon (supra). S. albifrons (Fourn.) Tryon, comb. nov., Cyathea albifrons Fourn. Ann. Sci. Nat. V, 18: 351. 1873. S. aramaganensis ee a) Tryon, comb. nov., Cyathea aramaganensis Kanehira, Bot. Mag. T on 48:731. 1934. S. aust tralis (Presl) Tryon, comb. nov., Hemitelia so Presl, Epim. Bot. 33. 1852, Cyathea eee (F.v.Muell.) C Ss. Brackenridgei (Mett.) Tryo - comb. nov. Cylhes Brackenridgei Mett, nn. Mus. Bot. Lugd.-Bat. 1:56. 3. [Cyathea sae a ak SA excelsa]. S. pane, (Bl.) Tryon (supra). S. Cooperi ( F.v.Muell. ) Foi , comb. nov., Alsophila Gooner x .V-Mpell Dom a of S. excelsa (Endl.) Tryon, comb. ay, Alsophila excelsa Endl. Pr oe Fl. i Dom S. feani (E. Brown) Tryon, comb. nov., Cyathea feani E. Brown, Bishop Mus. hive 89: 14. ma S. leucolepis (Mett.) Tryon, comb. gy er leucolepis Mett. Ann. . Bot. . 1863. ). S. medullaris (Forst.) Bernh., Cyathea medullaris (Forst.) Sw. S. microlepidota (Copel.) Tryon, comb. nov., Cyathea microlepidota :4 S. nigricans ( Mett.) re ha comb, nov., Cyathea nigricans Mett. Ann. Mus. Bot. Lugd.-Bat. 1:56. S. novaecaledoniae ie ny ) Tryon, comb. nov., Alsophila novae-caledoniae Meas Ann. Sci. Nat. IV, 15:82. 1861, Cyathea novaecaledoniae (Mett. ) ope S. Parksiae (Copel.) T ee comb. nov., Cyathea Parksiae Copel. Univ. Calif. Publ. Bot. 12: ert 1931. ropinqua (M ms oom comb. nov., Cyathea propinqua Mett. Ann. g 1863. - robusta ( Watts) ae comb. nov., Alsophila robusta Watts, Proc. Linn. Soc. N. S. Wales 39:261. 1914 (not de Vriese, in Junghuhn, Java, talt Pflanzend. zone art. 1:310, 476. 1852, nomen nudum), C ‘yathea — ( Watts ) a amoensis Brack.) Tryon, comb. nov., Alsophila samoensis Brack. US. Saeki st 16:287. 1854, Cyathea Whitmeei Baker THE CLASSIFICATION OF THE CYATHEACEAE 25 S. subsessilis — ) Tryon, comb. nov., Cyathea subsessilis Copel. Phil. Jour. Sci. 6 (Bot.): 359. 1911. S. truncata ( Brack.) Tryon, comb. nov., Alsophila pees Brack. U. S. Jour. Sci. 6 (Bot.): 360. 1911. S. vittata (Copel.) Tryon, comb. nov., Cyathea vittata Copel. Phil. Jour. Sci. 60:102. 1936. [Cyathea Whitmeei—Sphaeropteris samoensis]. 4, ALSOPHILA cee R. Br. Prod. Fl. Nov. Holl. 158. 1810. Type: Alsophila australis ‘Gum nosphaera Bl. Enum. PI. Jay. 242. 1828. Type: Gymnosphaera glabra ae = Also (pene ssity or ies mphic ardn. a yoink Bot. 1:441. 1842. Lectotype: Amphi- penis: ‘davis ‘wil ) Gardn. (Cyathea pk 3 Willd. ) = Alsophila capen- sis (L. f.) Dichorexia Presl, re ET et der Farrn, 36. 1847 (preprint from Abhandl. béhm. Ges. V, 5:344. 1848). Type: Dichorexia latebrosa ( Hook.) Pres] = hie se ila latebrosa ciate Thysanobotrya vAvR. Bull. Jard, Bot. Buitenz. II, 28:66. 1918. Type: Thenabowre vine ees vAvR. (Polybotrya arfakensis Gepp) = Alsophila biformis Rose Petiole smooth to tuberculate, or with corticinate spines (with squam- inate spines in one species ), lackin tiioldaics (in species examined ); petiole i I side) more or less ee attached either at one point of a pseudopeltate “ peltate base or at a thicke ned base (rarely n the edge of the scale; minute indument o the petiole, when pret of cog ody 0 ia ee ( ¢ rar si a labrous; veins in lobed or pinnatifid segments the basal vein on ea nebo sove the base of the sinus; indusium absent, or exten g al i Ae "scale Hike to sphaeropteroid. The name Amphicosmia might appear to be superfluous be- cause Gardner included Cyathea multiflora, the type of Hemitelia, in his genus. However, the typification of Hemitelia had not been settled at that time and Gardner explicitly considered Cyathea horrida to be the type of Hemitelia. Alsophila (Figs. 22-30) is a pantropic genus of about 230 species, poorly represented in America by about 12 species, well represented in Africa-Madagascar by about 60 species and from India and Ceylon to southern Japan, the Auckland Islands and to the Marquesas by about 160 species. In the paleotropics the 26 ROLLA TRYON genus is exactly Cyathea subgenus Cyathea Holttum (1963, 1964, 1965), including section Cyathea and section Gymnosphaera. Most American species, for example, A. Brooksii, A. Nockii and A. Urbanii, form a distinct group of indusiate bipinnate species in the Greater Antilles which perhaps has affinities with similar spe- cies of Africa and Madagascar. The two other American species, A. capensis (also in Africa) and A. Salvinii, are evidently related to species of the section Gymnosphaera. The size and diversity of Alsophila suggest that further studies are desirable to determine the major evolutionary lines within it. A chromosome number of n=69 has been reported, for example, in A. gigantea (as Cyathea gigantea) by Manton and Sledge (1954). The genus is characterized by its differentiated petiole scales that are marginate and apically setate, and by the petiole spines that (when present) are corticinate (Fig. 22) and arise from the petiole tissue. The cellular differentiation of the petiole scale margin is of two types which are connected by intermediates. One type (Fig. 26), similar to that found in Nephelea, has the thin walled marginal cells more or less isodiametric in shape and abruptly distinct from the heavy walled, elongate cells of the central portion of the scale. The other type (Fig. 27) has more elongate marginal cells which gradually differ from the cells of the central portion as they approach the edge of the scale. The scales of Alsophila Nockii (Figs. 29, 30) are more or less inter- mediate between these two types. All of the species of Alsophila that I have seen have an apical seta on some of the petiole scales and, except in a few species of Madagascar, it is dark in color. The seta is more or less concolor- ous with the brownish scale body in A. Ballardii, A. bellisquamata, A. Hildebrandtii, A. Hyacinthei and A. similis of Madagascar. Two further developments in the petiole scales are of interest. One is in Alsophila Urbanii of the West Indies, which has small and rather thickened and fleshy petiole scales. They are similar in their texture to some of the species of Sphaeropteris having thick- ened and fleshy scales. The other development is the squaminate spine of A. auriculata in Madagascar. The species is similar in this respect to the genus Nephelea and, in addition, the stem is spiny as it is in some Nephelea species (whether the unexpanded croziers also have spines like Nephelea is not known). I believe THE CLASSIFICATION OF THE CYATHEACEAE 27 RAN, 23 diese’ WOE OSES — \ h ee SS UE SS ey slats NT NO © IG 4 Up i iy ye 4, co} (%? ee RSS 4) I if Z' Yi) rf SSCL OE HYD ——— ro i Ss =o S—— =~ eat 2 |e, 9 ae ae i, i ( BORIALYY (Ex, iy LI mY Fics. 22-30. Atsopuita. Fic. 22. Corticinate petiole spine bearing a scale, A. et, GHe: Figs: 23-30. Portions of petiole scales: 23, A. Manniana, Tryon & Tryon 5626, X 90, GH. 24, Apex, 4. Manniana (as in Fig. 23). ? » . cap SS é X 30, GH. 27, A. Salvinii, Hernandez X-336, X 30, US. 28, Apex, A. Salvinii “—* Fig. 27). 29, A. Nockii, Underwood 1355, X 30, NY. 30, Apex, A. Nockii (as in Fig. 29). 28 ROLLA TRYON that these evolutionary developments in A. auriculata are inde- pendent of those that led to the squaminate spine in Nephelea. Other species of Madagascar show intermediate conditions of variously thickened and rigid scales and I interpret these as evidence for a local origin of the squaminate spines of A. auricu- lata. In A. albida the scale base is broad and slightly thickened; in A. Hildebrandtii it is thicker; in both the scale is borne on a cortical tubercule. In A. Melleri the scale base is quite thick and a cortical tubercule is evidently lacking. In A. Rolandii much of the scale is thickened, rigid and rather spine-like; its apical portion is somewhat flattened and its base is borne directly on the petiole. This represents a condition only slightly less extreme than that in A. auriculata which has spines. The orientation of the thickened scales changes in this series of species, from a rather appressed one (parallel to the petiole surface ) in the first species, A. albida, to a patent one in the last, A. auriculata. The development of thickened and rigid scales somewhat similar to that of A. Melleri and A. Rolandii is also seen in A. Brooksii and A. minor of the West Indies. In these species the specialized scales occur at the very base of the petiole, where it blends into the stem, and in A. Brooksii some of the scales are quite spine-like. One of the notable evolutionary trends in Alsophila is the devel- opment of aphlebiae. I believe that these are found only in Alsophila and, at least in their typical development, only in species that have been placed in the section Gymnosphaera. The phyletic significance of this character is not wholly clear and it is possible that aphlebiae have evolved more than once from species with normal leaves. The aphlebiae are typically borne at the very base of the petiole and they form a kind of lacy crown at the stem apex. In some species they are highly dissected and are very different from the normal pinnae (from which they are probably derived ). The aphlebiae of A. capensis were twice described as new species of Trichomanes (T. incisum Thunb. and T. cormophyllum Kaulf.). Tardieu-Blot (1941) discusses aphlebiae with special reference to the species of Madagascar and presents the various concepts of their nature and origin. The current literature on African Cyatheaceae does not include all of the proposed species and, because of doubt about their taxonomic status, some of these have not been included in the following list. THE CLASSIFICATION OF THE CYATHEACEAE 29 WEST INDIES Alsophila Abbottii (Maxon) Tryon, comb. nov., Cyathea Abbottii Maxon, Proc. Biol. Soc. Wash. 37:98. 1924. A. Brooksii (Maxon ) A comb. nov., Cyathea Brooksii Maxon, Contrib. U.o. aor Herb. ne 24. 1909. A. nis (C.Chr.) Tryon, comb. nov., Cyathea confinis C.Chr. Kungl. rn vo ar Handl, III, 16(2):13. 193 ode A. dryopteroides (M on) Tryo athea dryopteroides ax mn, comb, nov., Cy Maxon, Amer. Fern Jour. 14:99. 1925, not Alsophila dryopteroidea Brause 7% ‘Woatean na (C. Chr. & Ekman) Tryon, comb. nov Fg hotteana C.Chr. & Ekman, Kungl. Svensk. Vie -akad. Hand. Il, 16(2): 712, 1937. A. minor (D. C. E gr, ae mb. nov., Cyathea minor D. c Eaton, Mem. lati as n.s., 8:2 77860. A. Nockii len nm. ) fs penis nov., Cyathea Nockii Jenm. Jour. Bot. 47; 57, 1879 A. Urbanii (Brause) Tryon, comb. nov., Cyathea Urbanii Brause, in Urban, Symb. Ant. 7:151. 1911. MEXICO AND CENTRAL AMERICA Alsophila Salvinii Hook. SOUTH AMERICA ~ Alsophila capensis (L.f.) J.Sm. Hemitelia capensis (L.f.) Kaulf. A. Engelii Tryon, nom. nov. for Cyathea elongata Karst. Fl. Columb. 2:159 » .- (sub Cyathea aoresh t. ee f. IL, f. 5. 1869 (leg. Engel B!), not Alsophila © - elongata Hook. Sp. Fil. 1:43. : . paucifolia aha ale 7 oa: 2, 456. 1874. AFRICA, MADAGASCAR AND INDIAN OCEAN Alsophila acutula Tryon, nom. nov., for Cyathea tsaratananensis Tard. Bull. Soc. Bot. France 88:681. 1941, not C.Chr A. albida omer ) Laie comb. nov., Cyathea "albida Tard. Bull. Soc. Bot. France 88:680. alticola (T ard.) een comb. nov., Gymnosphaera alticola Tard. Naturaliste Malag. 3:76. a‘; A. pelea tay Tard. Gynmosphar agclobabe! ensis (Tard.) Tard. A. appendicul nar” ae on, comb. nov.. Cyathea appendiculata PS UG tees Linn. 15:4 1876. : A. approximata (Bonap. ) oo comb. nov., Cyathea approximata Bonap. Notes Ptérid. 5:41. = auriculata (Tar ) Tryon, comb. nov., Cyathea auriculata Tard. Natur- aliste Malag. 3:75. 1951. Ball bei (7 (Tord. ) elec comb, nov., Cyathea Ballardii Tard. Natur- alist nn 3: es ayia pe aye comb. nov., Cyathea bellisquamata hore, rena aoe tiy 16:18. 30 ROLLA TRYON A. Boivinii Ettingsh. Gymnospaera a (Ettingsh.) Tard. [Cyathea Boivinii=Alsophila Hyacinthei A. ae bonica Py e's Tryon, ig? ey - Cyathea borbonica Desv. Ges. 8. 1811. A. Ghaenoreiice ( Hook. ner: comb. nov., eet camerooniana A. Tryon, nom. for Cyathea excelsa, Sw. “Gebel Jour. Bot. 1800(2): 93. 1801, aes Alsophila excelsa Endl. [Cyathea costularis=Alsophila Rolandii]. A. Coursii Tar Asean Coursii (Tard.) Tard. A. Deckenii (Kuhn) T comb. nov., Cyathea Deckenii Kuhn, in v. Decken Reis. Ost. “Afr. 3(3) Bot :57. 1879. A. decresc ny (Kuhn) Tryon, sat nov., Cyathea decrescens Kuhn, Fil. Afr. 164, 1 A. seine orn ) Tryon, comb nov., Cyathea Dregei Kze. Linnaea 10:551. [Cyathea hae Seren a celsa]. A. glaucifolia Tryon, nom. nov., for Cyathea glauca Bory, Voy. Iles Afrique 2:206. 1804, not Alsophila ‘glauca (BI.) J.Sm. Ferns Brit. & For. 245. 1866. A. Hildebrandtii (Kuhn) Tryon, comb. nov., C yathea Hildebrandtii Kuhn, Ind. Sem. Hort. Berol. 20. 1875. [C yathea H olstii=Alsophila peomepelets ]. mbertiana (C.Chr.) Tryon, comb. nov., Hemitelia Humbertiana c.Chr. Arch, Bot. (Caen) Bull. Mens. 2:210. 1928, Cyathea Humbertiana (C. Chr.) D A. Hyacinthei Tryon, nom. nov., for Cyathea Boivinii Kuhn, Fil. Afr. 162. 1868, not Ettingsh.. Cyathea rigidula Baker, not Alsophila rigidula Mart. soe is (C.Chr.) Tryon, comb. nov., Cyathea isaloensis C.Chr Danek. Ark. 7:35. A. tr ‘(Hook.) Tryon, eon. nov., Cyathea Kirkii Hook. Syn. Fil. 22. A Lastii a Tryon, comb. nov., Cyathea Lastii Baker, Jour. Bot. 29:3. 1891 A. leptochlamys cial Tryon, comb. nov., Cyathea leptochlamys Baker, ere Linn. Soc. 22 ‘ A. ligulata (Baker Pond comb. nov., Cyathea ligulata Baker, Jour. Bot. “99: 140. 1 . longipi gio _(Bonap. ) Tryon, comb. nov., Cyathea longipinnata Bonap. Notes Bhten 5:4 adagascari Be ooh slid Gymnosphaera ew (Bonap.) Tard. [Cyathea sidiiaidiaduricdsahleoeniae maititane a, Pier Hook.) Tryon, comb. nov., Cudthes Manniana Hook. Syn. Fil. 21. 1865. A. eee —— ) Tryon, comb. nov.. Cyathea marattioides Kaulf. Enum. Fil. 256 A. matitanensis — om. nov., for Cyathea madagascarica Bonap. psn Ptérid. 5:49. 1917, not Alsophila gga abi Bonap. A. melanocaula (Desv.) Tryon, comb. n athea melanocaula Desv. Mém. Soe. Linn . Paris 6:322. 1827 (not ‘alsophila melanocaulos vAvR.). A. melanotricha Tard. , Gymnosphaera melanotricha (Tard.) Tard. THE CLASSIFICATION OF THE CYATHEACEAE 31 A. Melleri (Baker) Tryon, comb. nov., Hemitelia Melleri Baker, Syn. Fil. ba 2 456. 1874, Gymnosphacr Melleri. (Baker) Tard Mildbraedii Brau . mossambicensis (Baker) Tryon, comb. nov., Cyathea mossambicensis Baker, Ann. Bot. 5:185. 1891. A. Nicklesii (Tard. & Ballard ) feed comb. nov., Gymnosphaera Nicklesii Tard. & Ballard, Not. Syst. 14:329 A. bd Shea Hook, Cyathea pele (Hook. ) Dom rtho inne (Bonap. ) Tryon, comb. nov.. Cyathea poe eae Bonap. Miner eer rrieriana ot rete) ben comb. nov., Cyathea Perrieriana C.Chr. Dansk Bot. Ark. 7:19. 1932 A. pilosula pened Tryon, comb. nov., Cyathea pilosula Tard. Bull. Soc. Bot. France 88:681. A. quadrata Caer) Tey comb. nov., Cyathea quadrata Baker, Jour. Linn. Soc. 15:411. 1876 Pad a ee Baker=Alsophila Hyacinthei]. ryon, nom , for Cyathea costularis Roland Bonap. Notes Psd °: ode 1917 not Alsophila costularis Baker hli (Cueilien Schieber: *Aloiighile parrmesre A. sechellarum (Mett.) Tryon, comb. nov., Cyathea sechellarum Mett. Ann. Mus. Bot. Digk: -Bat. 1:58. 1863. a A. serratifolia (Baker) Tryon, comb. nov., Cyathea serratifolia Baker, 884. A. similis SeNaah m Tryon, comb. nov., Cyathea re C.Chr. Ind, Fil. 195. 1905, nom. . for Cyathea discolor Baker, n A. StuhIlmannii (exon ) Tryon, comb, nov., etlies ectinaiet Hieron. Bot. Jahrb. 28:34 A. tanzaniana Tryon, nom. nov.. for Cyathea Schliebenii ng Notizbl. Bot. Gart. Berlin 11:916, 1933, den ‘Arophtia Schliebenii Rei Thomsonii (Baker) Tryon, comb. nov., Cyathe thea Thomsonii Baker, Jour. ae i 180. 1881 nanensis (C. Chr.) Tryon, comb. nov., Cyathea tsaratananensis C.Chr. ind. Fil. Supp pl. 3:64, 1934, nom. nov. for Cyathea subincisa C.Chr., not (K [Cyathea tsaratananensis Tard. pee oe acutula]. A A. tsilotsilensis (Tard. ) Loar mb. ., Cyathea tsilotsilensis Tar Bull. Soc. Bot. France 88:682. Bocas A. Viguieri ae ) Tryon, ser nov., Cyathea Viguieri Tard. Bull. Soc. Bot. France 88: 682. iS : > A. bl ledge eee ) Tryon, comb, nov., Cyathea Welwitschii Hook. Syn. Fil. 2 f A. hors nensis is (Tar d.) Tryon, comb. nov., Cyathea zakamenensis Tard. Bull. Soc. Bot. France 88:683. 1941. ASIA ypc _— Bedd. Cyathea —— (Bedd.) Copel. s (Copel. ) eee a mb. Cyathea borneensis Copel. Phil. fon “Sci. 6 (Bet ji 135. 1 [Cyathea chinensis=Alsophi sila pres ris]. A. posretins Baker, Cyathea chinensis Copel. 32 ROLLA TRYON A. denticulata Baker, Cyathea Hancockii Copel. A. gigantea Hook. Cyathea gigantea (Hook.) Copel. [Cyathea Hancockii=Alsophila denticulata]. . Henryi Baker, Cyathea Henryi (Baker) Copel. . Hookeri ( Thwaites) Tryon, comb. nov., Cyathea Hookeri Thwaites, Whee» Pl. Zeylan. 396. 1864. . khasyana Kuhn, Cya thea khasyana { Kuhn) Diels. A. —— Hook. Cashed ietabrosa: (Hook.) Copel A. Loheri gee ae comb. nov., Cyathea Loheri Christ, Bull. Herb. Boiss. t 6:1 . eniana Hance Cyathea Metteniana (Hance), C.Chr. & Tard. aera (H tt.) Tryon, comb. nov., Cyathea nilgirensis Holtt. Kew Be 19:468. 1965. ‘A; podophylla A. Salletii (Tard. & C.Chr.) Tryon, comb. nov., te a Salletii Tard. & C.Chr. Bull. Mus. Hist. Nat. Paris. I, 6:450. 19. A. sinuata — & — ) Tryon, comb. nov. , Cyathea sinuata Hook. & Grev. Icon. Fil. t. A. _ (Hook: ae comb, nov., Cyathea spinulosa Hook. Sp. Fil. 1 1844. A. was (Hook.) J.Sm. Cyathea Walkerae Hook. MALAYSIA Alsophila acanthophora (Holtt.) Tryon, comb. nov., Cyathea acantho- phora Holtt. Kew Bull. 16:51. A. mid rniower vAvR., Cyathea acrostichoides (vAvR.) Dom A. acuminata (Copel) Tryon n, comb. nov., Cyathea pave ey Book Phil. oes Set 81:15. ~_ . (Alsophila acuminata J.Sm. Lond. Jour. Bot. 1:667. 1842 is a nomen m). A. ‘Aldeemeeuher "(Co opel.) Tryon, comb. nov., Cyathea plsenersl Copel. Phil. Jour. Sci. 4 (Bot): 50. heii nom. nov. for Hemitelia sumatra vAvR., not C yathe, ea aria Ba A. alleniae — tt.) Tryon, pe nov., Cyathea Alleniae Holtt. Kew Bull. 16:52. A. ee vAVE, , Cyathea trachypoda vA ; ensis vAVR , Cyathea eric (vAvR.) Merrill. : reve vAvR., Cya athe Annae (vAvR.) Domin. pip omens Rosenst Cyathea apiculata (Rosenst.) D apoensis gee ) Tryon. comb. nov., Cyathea pase Copel. Leafl. Pi Bot. 3:802. A. Archboldii (Cc. Chr.) Tryon, comb. nov., Cyathea Archboldii C.Chr. Brittonia 2: saa 1937. A. ee Gepp, Cyathea Kanehirae Holtt. Cyathie & arfakensis—Alophil Lilianiae]. — ascendens= atro: opel rneensis (Copel.) Tryon ee. THE CLASSIFICATION OF THE CYATHEACEAE 33 A. Brausei Tryon, nom. nov., for Cyathea wae 0% Brause, Bot. Jahrb. 56:58. 1920, not Alsophila Hunsteiniana Braus A. Buennemeijeri (vAvR.) Tryon, comb. nov., ‘Cyothes Buennemeijeri vAvR. Bull. Jard. Bot. Buitenz. III, 5:187. 1922. A. callosa Niel Tryon, comb. nov., Cyathea callosa Christ, Bull. Herb. ans II, 6:1008 A. catillifera “tot ) Tryon, comb. nov., Cyathea catillifera Holtt. Kew Bull. 16:53. 196 A. te ata He ok. Cyathea caudata bagi Copel. [Cyathea Christii=Alsophila Herm A. cincinnata to Tryon, ome nov., Cyathea cincinnata Brause, Bot, Jahrb. 56:52. 1920. A. ciner reat Copel) ate comb. nov., Cyathea cinerea Copel. Leafl. Phil. Bot. 5:1 A. ae wer Tryon, comb. nov., Cyathea coactilis Holtt. Blumea 11:533. A. peinaiaa Mett. ri mpi serge Copel. A. costalisora (Copel.) Tryon, comb. nov., Cyathea costalisora Copel. Univ. Calif, Publ. Bot. 18:218. 194 [Cyathea costulisora=Alsophila eld ]. A. crassicaula Tryon, nom. nov., for — sng oe Brause, Bot. ny bon 56. ate eu Alsophila Lederma enulata tt.) Hook. Cyathea Raciborsk Copel. [Cyathea crenuata Alpi polycar A. ifer bi tt.) Tryon, comb. nov., Cyathea cucullifera Holtt. Kew Bull. 16:54. A ickvondbisies (ote ) Tryon, comb. nov., Cyathea dicksonioides Holtt. Blumea 11:529. 1962 A. dimorpha Christ, Cyathea dimorpha cen Copel. A. Doctersii (vAvR. ) igirad age nov., Cyathea Doctersii vAvR. Bull. Jard. Bot. Buitenz. III, 2:136. ix. icine se es ) ‘Tryon, Sans nov., Cyathea Edanoi Copel. Phil. Jour. sl 46:2 eiophora “iol. ) Tryon, comb. nov., Cyathea eriophora Holtt. Kew Bull 16: 55. A. evert eeaeed ) si ag comb. nov., Cyathea everta Copel. Univ. Calif. Publ. Bot. 18:218. 194 A. repos cts ‘Tryon. comb. nov., Cyathea excavata Holtt. Gard. Bull. Str. 8:306. 19 A; Fenicis (Cope is ) C.Chr. Cyathea Peisaid — A. ferruginea rist ) rae comb. , Cyathea ferruginea Christ, Phil. Jour. Sci. 2 Tae 181. 190 A. Foersteri ( Rosenst. ) Tryon, comb. nov., Cyathea Foersteri Rosenst. bres Repert. 10:321. 1912 liginosa Christ, Cato fuliginosa (Christ) Copel. oc x geluensis Aare t.) Tryon, comb. nov., Re geluensis Rosens Fedde Repert. 5:371. A. gigantea Hook. Cyat athee gigantea (Hook.) H A. glabra ( Bl.) Hook. roa glabra (Bl.) Co ang : Holtt re mea (Holtt.) Tryon, comb. nov., Cyathea glaberrima Holtt. Kew Bull. 16:55. 1962. glei Haiti (e - Tryon, comb. nov., Cyathea gleichenioides Cc Chr. Brittonia 2:281. 1 34 ROLLA TRYON A. gregaria Brause, Cyathea gregaria eae) Domin. halconensis (Christ ) Tryon, comb. ., Cyathea ‘halconensis Christ, Phil. Jour. Sci. 3 (Bot.): 270. oer A. Havilandii (Baker) Tryon, comb. nov., Cyathea Havilandii Baker, Trans. Linn. Soc. Lond. II, (Bot.) i. 249. 1894, nnii as nom. nov., for Cyathea Christii Copel. Phil. Jour. Sci. 1, Suppl. II: 144. 1906, not Alsophila Christii Sod chlamydea (Co ryon, ov., Cyathea hetero- chlamydea Copel. Leafl. Phil. Bot. 2:418. :41 y ooglandii (Holtt.) Tryon, comb. nov., Cyathea H ooglandii Holtt. Kew Bull. 16:56. 1962. A. Hornei Baker, Cyathea Hornei (Baker) Copel. A. horridula (Copel. ) Tryon, comb. nov., Cyathea horridula Copel. Univ. Calif. Publ. Bot. 18:219. 1942. [Cyathea dng aca Alsophila Brausei]. A. hymenodes ( Mett.) T is comb. nov., Cyathea hymenodes Mett. Ann. Mus. Bot. Lugd. Bat. 1:57. A. imbricata og ) ai comb. nov., Cyathea imbricata vAvR. Nova Guinea 14:11. A. insoserat Seal) C.Chr. Cyathea incisoserrata Copel. A. inquinans (Christ) Tryon, comb. nov., Cyathea inquinans Christ, warps ews Natu rf. Ges, Base] 11:422. 1896. A. —— (Holtt.) Tryon, comb. nov., Cyathea insulana Holtt. Kew Bull. 16:56, 1962. A. javanica (Bl.) Tryon, comb. nov., Cyathea javanica Bl. Enum. Pl. Jav. 245. 1828 A. Junghuhniana Kze. Cyathea i a (Kze.) Copel. [Cyathea ik =Alsophila arfaken: A. Klossii (Ridley) Tryon, comb. nov., “Rbethes Klossii Ridley, Trans. . 1916. A. latebrosa Hook. Cyathea latebrosa ( Hook.) Copel. A. latipinnula (Copel.) Tryon, comb. nov., Cyathea latipinnula Copel. Leafl. Phil. Bot. 4: 1149. 1911. [Cyathea Ledermannii=Alsophila crassicaul. A. os Christ, Coates —— Weea\ Domin aniae Tryon, nom. nov., Cyathea arfakensis Gepp, in Lilian S. cece" Dutch N.W. New Cuinca 60. — pe Alsophila arfakensis Gepp. A. Loerzingii (Holtt.) Tryon, comb. nov., Cyathea Loerzingii Holtt. Kew Bull. 16:58, 1962. A. Loheri (Christ) Tryon (supra). . longipes (Copel.) Tryon, comb. nov., Cyathea longipes Copel. Phil. Jour. = fy (Bot.): 54. 1917. da (Bl.) Hook. Cyathea lurida ( Bl.) Co rm poral Saeve Baker, Cyathea Macgillivrayi Cakes) Di A. Macgregorii (F. v. Muell.) Tryon, c cape gy ag Macgregorii F. v. se Trans. Ro oy. Soc. Victoria 1(2):4 1889. A. macropoda (Domin) Tryon, comb. nov., Cyathea macropoda D Acta Bot. Bohem. 9:133, 1930, nom. nov. for Deches. longipes uple go opel. A. ee (vAvR. ) bap ier comb. nov., Cyathea magnifolia vAvR. Bull. Jard. Bot. Buitenz. Ill, 2:135. 1920. A. masapilidensis (Copel. ) yp comb. nov., Cyathea masapilidensis Copel. Phil. Jour. Sci. 81:17. 1952. THE CLASSIFICATION OF THE CYATHEACEAE 35 A. media (Wagn. & Greth.) Tryon, cone nov., Cyathea media Wagn. & Greth.. Univ. Calif. Publ. Bot. 23:44. 194 A. mesosora (Holtt.) Tryon, comb. nov., Cyathea mesosora Holtt. Kew Bull. 16:57. 1962. Placed by Holttum (1963) among species of Sphaerop- teris, but I believe pio it Seana oa in Alsophi A. micra Tryon. Cyathea parva Copel. Univ. Calif. Publ. Bot. 18:219. 1942, ain ap] poe ax icrochlamys (Holtt.) Tryon, pa nov., Cyathea microchlamys 6: 2. A. microphylloides (Rosenst. ) ae comb. nov., Cyathea microphylloides pees Fedde Repert. 12:164. 191 modesta rere erahe ak eA Copel c montana (vAvR.) Tryon, com mitelia monte) Al Bull. Jard. Bot. Buitenz. III, 2:153. 1920, Cyathea costulisora D A. Muelleri (Baker) Tryon, comb. nov., Cyat thea Muelleri pe ae Jour. Bot. see A. na (Chr st) been comb. nov., Cyathea negrosiana Christ, Phil. jour. "Sci 2 re 181. A. ee aie ) tii mes nov., Cyathea nigrolineata Holtt. Kew Bull. 16:5 A. nigopaeata (Hole ) Tryon. comb. nov., Cyathea nigropaleata Holtt. Kew Bull. 16:59. 1 A. oinops ‘Gia cy Tryon, a nov., Cyathea oinops Hassk. Jour. Bot. Hook. Kew Gard. Misc. 7:322. 1 A. oosora (Holtt.) Tryon, sep nov., Cyathea oosora Holtt. Kew Bull. 16:59. 1962. A. orientalis (Kze.) Tryon, com nov., Diet orientalis Kze. Bot. Zeit. 6:283. 1848, Cidthes orientalis ( Kze.) Moor A. pachyrrhachis ( Copel. Teas comb. nov., Cyathea pachyrrhachis si Univ. Calif. Publ. Bot. 18:218. a A. pallidipaleata (Holtt.) Tryon, sa nov., Cyathea pallidipaleata oe ind Bull. 16: Hs Cyathea parva=Alsophila mic A. saselitees (vAvR. ee comb. nov., Cyathea patellifera vAvR. Bull. Jard. Bot. Buitenz. II, 16:4. 19 : A. pag acrageeh - Chr. ) Tryon, comb. nov., Cyathea percrassa C. Chr. Brit- tonia 2:279. 2 . perpel vigera _ ) Tryon, comb. nov., Cyathea perpelvigera vAv Nova —_ 14:11. 1924. ue A. ichie (vAvR. ) Tryon, comb. nov., Hemitelia perpunctu - Bice Bull. sa Bot. Buitenz. II, 28:25. 1918, Cyathea perpunctulata apalgn tae hea physolepidota A. ecedeadate ered Tryon, comb. nov., Cyathea physolep ae Hace Guinea n.s. 7: ict Beeld ie ian , comb. nov., - ck mek Shea jung.) yo 2: 40. 1845, Cyathea crenulata Bl., not Tonas k. enulata salt ‘Hosenek:) Tryon, comb. nov., Cyathea pruinosa Rosenst. Fedde 1913. ; A pseudomueie (Flt. Tryon, comb. nov., Cyathea pseudomuelleri Hal ass ek h ctulat Ae Lab ) vAvR To Cae unctulata (Vv A. a. yenoneur out ig ot mn, comb. .. Cyathea pycnoneura Holtt. Blumea 11:533. 36 ROLLA TRYON par niet iors crenulata]. ook. Cyathea ramispina ( Hook.) Copel a Hifeteas F. v. Muell. Cyathea Rebeccae (F. v. Muell. ) Domin. [Cyathea recommutata—Alsophila commutata A. archer Brause, Cyathea recurvata (Brause) Dom gens ogee ) Tryon, comb. nov., Cyathea vo Rosenst. Fedde eben: 12:163. A. Rosenstock Brause Cyathea ascendens Dom A. oo (Holtt.) Tryon, comb. nov., Cecilie panes Holtt. Kew Bull. 16:61. - sare Brause, Cyathea renee (Brause) Dom rufopannosa (Christ Tryon, b. nov., Cyathea Adil wuis Christ, Phil Jour. Sci. 2 (Bot.): 180. 19 07. A. saccata (Christ) Tryon, comb. nov. , Cyathea saccata Christ, Ann. Jard. Bot. Buitenz. II, 4:42. 1904. A. scandens Brause, Seatac scandens ( Brause) Domin. Schlechteri Brause, Cyathea Schlechteri (Brause) D A. semiamplectens ( Holtt. Tryon, comb. nov., a es coontytbedis Holtt. Kew Bull. 16:62. A. setulosa 5s ge Tryon, comb, nov., Cyathea setulosa Copel. Phil. ard Sci. 81:14. 1952 A. subtripinnata (Holt ) Tryon, comb. nov., Cyathea subtripinnata Holtt. Bivines 11:534. 1962 sumatrana (Baker) Tryon, comb. nov., Cyathea sumatrana Baker, Jour. Bot 18:2 880. A. tenuis Brause, Cyathea tenuicaulis Domin A. seiies atea (v ing comb. nov., Cyathea ternatea vAvR. Bull. Jard. Bot. Buitenz. II. 5:191. 1922. [Cyathea trachypoda—Alsophila alpina]. . Vandeusenii (Holtt.) Tryon, comb. nov., Cyathea Vandeusenii Holtt. Blumea 11:529. 1962. A. wengiensis Brause, Cyathea wengiensis (Brause) Domin. AUSTRALASIA AND PACIFIC [Cyathea affinis=Alsophila tahitensis]. Alsophila alata Fourn. Cyathea alata (Fourn.) Copel . alta (Copel.) Tryon, comb. nov., Cyathea alta Copel. Phil. Jour. ‘ae 60: 104. - ee ( Hook.) Tryon, comb. nov., Cyathea aneitensis Hook. Syn. Fi 1865. A. eee (C.Chr.) Tryon (supra). A. australis R.Br. Cyathea australis (R.Br.) Domin - Baileyana Domin, Cyathea Baileyana (Demin). Domin. A. brevipinna (Benth. ) Tryon, comb. nov., Cyathea brevipinna Benth. Fl. us tral. 7:709. 1878. cicatricosa ( Holtt. ) Tryon, comb. nov., Cyathea cicatricosa Holtt. Paths 12:274, 1 Colensoi Hook. f. area Colensoi (Hook. f.) D = ——— (Hook. f.) Tryon, comb. nov., bain Ednninahanl Pl. t. 985. 1854. (Cyathea d dealbata—Alsophila tri color] decurrens Hook. Cyathea prsanachs ( Hook.) Copel. # THE CLASSIFICATION OF THE CYATHEACEAE 37 A. Ferdinandii Tryon, nom. nov., for Hemitelia Macarthurii F. v. aa ragm. Phyt, Austral. 8:176. 1 874, Cyathea Macarthurii (F. v uell. ) Baker, not jac cha Macarthurii Hook. Cyathea Moorei Baker, not ‘Alnus ei J.Sm = A. Hornei Baker (supra). A. k Srisetiatals ( Oliver ) aon, fone: nov., Cyathea kermadecensis Oliver, Trans. N. Z. Instit. 42:158. [C yathea Mabinesiosett— Ale aii ‘Ferdinandii] A. marcescens (N.A.Wakef.) Tryon, comb. nov., Cyathea marcescens N.A.Wakef. Victoria Nat. 59:33. : A. Milnei Ape i) a Soe comb. nov., Cyathea Milnei Hook. f. Handb. Fl. New Zeal. 3 A. kate ioe: ) Tryon, comb. nov., Cyathea plagiostegia Copel. sari“ oer Bull. = 9. 1929. ccae F. v. Muell. Cyathea Rebeccae (F. v. sa Domin. rs apnea F. v. Muell. Cyathea Robertsiana (F. v. ll.) Domin. A. Smithii (Hook. f.) Tryon, comb. nov., Cyathea coun Hook. f. FI. New Zeal. 2:8 ee ee (Holtt.) Tryon, comb. nov., Cyathea solomonensis Holtt. Bhusen 12:252. 1964. A. gecrg (Holtt.) Tryon, comb. nov., Cyathea stelligera Holtt. Blumea 12; rg: A. sii (E. Brown) — comb. nov., Cyathea Stokesii E. Brown, Bishop Mus Bull. 89:16. 1931. hitensis Brack. Cyathea affinis (Forst.) Sw., not Alsophila affinis ee Fée. a tricolor (Colenso) Tryon, comb. nov., Cyathea tricolor Colenso, Trans. w Zeal. Instit. 15:304. 1883, Cyathea dealbata (Forst.) Sw., not Also- ole dealbata Presl. A. Viei or (Mett. ) Tryon, comb. nov., Cyathea Vieillardii Mett. Ann. Sci. Nat. IV, 15:82. 1861. A. Woollsiana F. v. Muell. Cyathea Woollsiana (F. v. Muell.) Domin. 5. NEPHELEA Nephelea, genus novum Cyatheacearum = crosieribusque spinis squaminatis magnis atris sad squamis cellu argin natis setam atratam apicalem ferentibus. Nomen e nephele (Gr. aes species generis in_silvis nubilis plerumque habita ates. ” Typus: piateacse — ( Christ ) Petiole with squaminate spines, these tec Bisck, mostly a with a slender apex, the unexpanded croziers with w well developed squa usually in color from those of the central aga bearing a dark seta at the apex and sometimes one or more on the edge or dy o e cale gucci indument of the petiole, when present, of trichomidia and I of erage lae; = pubescent above; veins free, in lobed or pinnatifid segments the asa n each side extending ie the base of the sinus; indusium pesanat: hemitelioid to sphaeropteroi id. 38 ROLLA TRYON Nephelea (Figs. 3, 31-38) is an American genus of about 30 species. It is especially distinctive in its squaminate spines that are present on the petiole and are precociously developed on the croziers. Typical petiole spines and the spiny crozier are illustrated in Fig. 31. There is evidence clearly indicating that these spines have evolved from petiole scales. Species of Nephelea have some petiole scales thickened basally, some that are spine-like, and some that are small spines with the differentiated margins of the normal scales on each side (Figs. 32-34), as well as the larger spines. These transitional stages are indicative of a squamate origin of the spine proper, as are the caducous spines of the croziers that be- come detached at their very base. As noted in the discussion under Alsophila, the series of species leading to A. auriculata illustrates how, in Nephelea, the spines may also have evolved by thickening the sclerotic central portion of the scale. The lamina bears scales similar to those of the petiole, but much smaller, and these are an aid in identifying specimens of Nephelea that lack the petiole. However, similar small laminar scales with dark setae also occur on some American species of Alsophila. Some characters which show interesting evolutionary develop- ments are not mentioned in the description because they do not occur in all or most of the species. These are the pubescent indusi- um of species such as N. portoricensis and N. cuspidata, the spiny stems of species such as N. polystichoides and N. aureonitens (Fig. 38) and the very small petiole scales of species such as N. Sternbergii. The chromosome number of n=69 has been re- ported by Walker (1966) for N. Tussacii and N. Grevilleana (as Cyathea Tussacii and C. Grevilleana, respectively ). The following list of species will serve as examples of the genus. It does not include those in which problems of taxonomy or nomenclature are known. WEST INDIES Nephelea araneosa (Maxon) td comb. nov., Cyathea araneosa Max- on, North Amer. Fl. 16:74. 1909 N. balanocarpa (D. C. Eaton) ba fer nov., Cyathea balanocarpa D.C, —— Mem. Amer. Acad. n.s. 8:215. 1 a (Baker) Tryon, banat nov Ces arborea var. concinna Baker, J ping Bot. 19: 532. 1881, Cyathea concinna (Baker) Jenm. . crassa (Maxon) Tryon, comb. nov., Cyathea crassa Maxon, Contrib. U. 4 Nat. Herb. 13:40, 1909. THE CLASSIFICATION OF THE CYATHEACEAE 39 \\@ i" LS i a ae =e SSS Sep SSS we RN = ht, ett c. 31. Unexpanded crozier of N. polystichoides, Gastony Pia aes , the apical portion is the unexpanded crozier proper with spi ion n m the : ‘ p c o squamin tony 763, all X 8, GH. 32, Petiole scale thickened basally. ale. 34, Small squaminate spine. Fics. 35-37. Portions of petiole es: 35, Apex, N. purpurascens, Sodiro, July 1907, 450, US... 36, Apex, Sternbergii, Mexia 4650, , GH: 37, NV. Sternbergii, Dusén 6775, X 30, GH. Fic. 38. Portion of spiny stem of N. aureonitens, Gastony 763; << 1, GH. 40 ROLLA TRYON N. cubensis (Maxon) Tryon, comb. nov., Cyathea cubensis Maxon, North Armes: Fl. 16:73. 1909. N. Grevilleana (Mart.) Tryon, comb. nov., Cyathea Grevilleana Mart. Icon. Pl. Crypt. Bras. 78. 1834. N. Hieronymi ( Brause ) it bo bat nov., Cyathea Hiermonymi Brause, in Urban, Symb. Ant. 7:152 N. leven ( Hook. ) Tryon, psi nov., Cyathea Imrayana Hook. Sp. Fil. ag — N. portoricensis oe Tryon, comb. nov., Cyathea portoricensis Kuhn, Linnaea 36. 163. 1869. pubescens ‘Kuibn) Tryon, comb. nov., Cyathea pubescens Kuhn, ie ae Digs 186 N. Tussacii ( a) Tryon, comb. nov., Cyathea Tussacii Desv. Mém. Soc. Linn. ‘Paris 6:323. 1827. MEXICO AND CENTRAL AMERICA Nep Silas ea ge ( Christ ) earn comb. nov., Cyathea! aureonitens 1904. , a eons erb. Boiss. II, 4:948. } . bas aris (Christ) ae. comb. nov., Cyathea basilaris Christ, Bull. 7) ase pat: =i II, 4 N. mexicana (Samoa, Perse Tryon, comb. nov., Cyathea mexicana Schlect. & Cham. Linnaea 5:616 N. patellaris (Christ) Tryon, a nov., Cyathea patellaris Christ, Ann. Conserv. Jard. Bot. Genéve 4:20 00. . polystichoides (Christ ) Tryon, —_ ree Alsophila polystichoides Christ Bull. Soc. Bot. See 35 (Mém.): 1896. N. tenerifrons (Christ) Tryon, ay nov., Alsophila tenerifrons Christ, Bull. Herb. Boiss. II, 4:959. 1904. [Cyathea Werckleana—Nephelea polystichoides]. SOUTH AMERICA Nephelea canescens (Sod.) Tryon, comb. nov., Cyathea canescens Sod. Sert. Fl. Ecuad. 2:4. 1908. N. cuspidata (Kze.) Tryon, comb. nov., Cyathea cuspidata Kze. Linnaea 9:101. 1834. N. erinacea ( Karst.) Tryon, comb. nov. , Cyathea erinacea Karst. Linnaea 28:453. 1857. - purpurascens (Sod.) Tryon, comb. nov., Cyathea purpurascens Sod./ Crypt. Vasc. Quit. 503. 1893. N. setosa (Kaulf.) Tryon, comb, nov. re setosa Kaulf. Enum. Fil. 249. pos Panna setosa (Kaulf e bergii (Sternb.) Tryon, comb. nov., Cyathea Sternbergii Sternb. ) Fl. von Vacweatt 1:47. 1820 (I abe seen pen FL Monde Primitif 4:52. 1826). 6. TRICHIPTERIS hipteris Presl, Delic. Prag. 1:172. 1822, often as Trichopteris. Type: Trichipter vo Pres] = Trichipteris corcovadensis (Raddi) Copel. Chr Kaulf. Enum. Fil. 250. 1824. Type: Chnoophora Humboldtii ema nom. ok for Cyathea villosa Willd. = Trichipteris villosa (Willd.) ryon THE CLASSIFICATION OF THE CYATHEACEAE 41 Petiole smooth to tuberculate, or with corticinate spines, often with trichomes; petiole scales (especially on the abaxial side) more or less ap- pressed, attached at one point of a pseudopeltate or peltate base, structurally marginate, with a narrow to broad margin of cells different in orientation, siz i e central portion, | The alteration of the spelling of Trichipteris to Trichopteris, initiated by Schott (Gen. Fil. 1834) and later accepted by Presl and other authors, cannot be maintained. Trichipteris was used for the genus, for the species and in the index of the original publication. Although the name was derived from “trichos” and “pteros,” and Trichopteris may be considered as preferable, Presl’s original choice in the formation of the compound must stand. Martius is frequently credited with the valid publication of a genus Chnoophora, in his Icones Pl. Crypt. Brasil. 1834, but this is evidently incorrect. In the formal taxonomic treatment, pages 62-63, Martius explicitly treats Chnoophora Kaulf. as a synonym of Alsophila and as a section or subgenus of it. The species that appears as C. excelsa on t. 27 and t. 37 is given in the text as Alsophila (Chnoophora) excelsa. I believe that the formal text must take precedence in this case, and in others where the name Chnoophora is used. The generic name, when used by itself, should be ascribed to Kaulfuss and new binomials with it treated as published in synonymy. Trichipteris (Figs. 39-43) is an American genus of about 90 species. It is characterized by marginate petiole scales that lack ‘dark setae, normal, free venation (Figs. 42-43) and absence of an indusium. Trichipteris is nearly the equivalent of the classical Alsophila, in America, because there are only a few exindusiate species belonging to other genera in the neotropics. The cellular differentiation of the petiole scales is usually similar to that in - Cyathea and is described in some detail there. In some species, such as T. albidopaleata and T. aspera, the modified margin is very narrow; in others such as T. scabriuscula it is rather broad but poorly developed; in T. Wendlandii, although definite, it is both narrow and slightly modified. These examples of species with only slightly marginate scales nearly provide a connection with 42 ROLLA TRYON Sphaeropteris in which some species have tendencies toward marginate scales. Species of Trichipteris often grow at lower altitudes than those of other genera and it the only genus repre- sented in the Amazon basin. The chromosome number of n=69 has been reported by Walker (1966) for T. armata (as Cyathea armata). Recognition of Trichipteris and Cyathea as genera is based on evidence that each represents a separate evolutionary line. They are undoubtedly closely related and their evolutionary status and affinities could also be expressed by their classification as sub- genera. However, the large numbers of species in each enforces their claim to generic rank. A comparison of the species in these two genera has shown very few cases of close similarity between indusiate species of Cyathea and exindusiate Trichipteris. Aside from these cases, species groups and distinctive species seem to have closest affinities within their own genus. There are three groups of species that might indicate an inti- mate relation between Trichipteris and Cyathea: (1) Trichipteris armata and T. bicrenata with Cyathea acutidens and C. leucolepis- mata; (2) Trichipteris obtusa, T. oblonga and T. chnoodes with Cyathea columbiana; and (3) Trichipteris pubescens and an undescribed allied species with two undescribed species of Cyathea. Similarities among the species in these three groups are in characters of the lamina architecture and indument, the vena- tion, the relative length of the petiole and lamina and the habit. These characters may show convergent evolution in species of different genera. This interpretation is especially clear in the species of the third group. These four species all have a short petiole and a pinnate-pinnatifid lamina of similar size and shape which is pubescent on both surfaces. However, the two exindusi- ate species of Trichipteris have similar paraphyses and petiole scales and in these structures they differ from the two similar indusiate species of Cyathea. The characters common to the two pairs of species are best interpreted as convergent. Characters of the paraphyses and the details of the petiole scales, in addition to the indusium, are alike in members of other species-groups and they are a more certain guide to evolutionary affinity than the size, architecture and shape of the lamina and its pubescence. THE CLASSIFICATION OF THE CYATHEACEAE 43 of Vi GSS ~ WEN? Y. / ie LU hi A) A hic MY ge 3 Wace ( y 39 ii A—Y WZ NS. O LE, SiG > ‘ss 3 f petiol les: 39, T. mexicana, ges . F ex, T. mexicana (as in Fig. 39). 41, Apex, T. albidopaleata, Mexia 4869, X 150, GH. Fics. 42-43. Portions of pinnules showing i ptacles, all & 2. 42, T. arbuscula, Brade 8255, US. 43, T. compta, venation and rece L. B. Smith 6579, US. The following list of species will serve as examples of the genus. It does not include those in which problems of taxonomy or nomenclature are known. 44 ROLLA TRYON WEST INDIES vere ste (Sw.) Tryon, comb. nov., Polypodium armatum Sw. Prod. Veg. Ind. Occ. am 1788, Alsophila armata (Sw.) Presl, not Mart., Alsophila Swartziana T. aspera (L.) Tryon es a nov., Polypodium asperum L. Sp. Pl. 2:1093. 1753, Alsophila aspera (. ) Ss eng. T. borinquena hare ‘Tryon, comb. nov., Alsophila borinquena Maxon, Amer. Fern Jour. 15:56. T. Eatonii (Jenm.) hoes “comb. nov., Alsophila Eatonii Jenm. Journ. Bot. 25: Js Estellec (Riba) Tryon, comb. nov., Alsophila Estellae Riba, Rhodora 69: od 1967. T. Hodgeana gate Tryon, comb. nov., Cyathea Hodgeana Proctor, Rhodora 63:31. 1961. i rego iprch ‘(Hook Tryon. comb. nov., Alsophila sagittifolia Hook. Syn, Fil. 37. di prema ate n) Tryon, comb. nov., Alsophila strigillosa Maxon, Contrib. U. S. Nat. Herb. 24:37. 1922. [Alsophila Swartziana—Trichipteris armata]. MEXICO AND CENTRAL AMERICA hipteris bicrenata (Liebm.) Tryon, comb. a seats 4 els Bre Vid. § k, Skr. V, 1:289. 1849, Alsophila ue L T. chnoodes (Christ) Tryon, comb. nov., Alsophila ies ia Bull. j . 190 Herb. Boiss. II, 4:958. mexicana (Mart. ) “Tryon, comb nov., Alsophila mexicana Mart. Icon. T. wesiotica '(Maxe i Tryon, comb. noy., Alsophila nesiotica Maxon, / Contrib. U. S. Nat. Herb. 24:43. 1922, (Cocos Is: J: pansamalana (Maxon) Tryon, comb. nov., Alsophila pansamalana ~~ Maxon, Contrib. U. S. Nat. Herb. 24:40. 1922. T. scabriuscula (Maxon) Tryon, cone nov., Alsophila scabriuscula Max-. 19. on, Proc. Biol. Soc. Wash. 32:125. ore! ase (Pres!) Tryon, ra nov., Alsophila Schiediana Presl, 1836, Tent. Seles ws ‘ setlig PS a Tryon, comb. nov., Alsophila stipularis Christ, Bull. Hed. sec II, 4:958. 1904. T. trichiata (Maxon ) Pare solo agg nov., Alsophila trichiata Maxon, — U. S. Nat. Herb. 24:44 ursina Segoe ® Tryon, wie nov., Alsophila ursina Maxon, Jour. oy Acad. Sci. 944, T. Wendlandii ‘CKaho) Tryon, comb. nov., Alsophila Wendlandii Kuhn, Linnaea 36:1 T. Williamsii "ae on) eee eggs nov., Alsophila Williamsii Maxon, Contrib. U. S. Nat. Herb. 24:46. 1 SOUTH AMERICA richipteris albidopaleata (Copel.) Tryon, comb. nov., Cyathea albido- Bsr oo Univ. Calif. Publ. Pot. 17:25. 1932, Alsophila albidopaleata —— Ve Ss: seer ( Alston ) PS gr comb. nov., Cyathea anacampta Alston, | . 1958. jou Wash. Acad. Sci. 48:230 { THE CLASSIFICATION OF THE CYATHEACEAE 45 . arbuscula (Kze.) Tryon, comb. nov., Alsophila arbuscula Kze. Bot. _ Zeit. 2:313. 1844, T. atrovirens (Langsd. & Fisch.) Tryon, comb. no olypodium 9p 2 . & virens vote & Fisch. Icon. Fil. 12. 1810, Alsophila sre (Langsd F % ) Pre ay tine gig Tryon, comb. nov., Alsophila bulligera Rosenst. Fedde R Repert. 25:57. T. caracasana ta ) Tryon, comb. noy., Alsophila caracasana KI. Linnaea 18: jam 1844. mpta (Mart. o Tryon, comb. nov., Alsophila compta Mart. Icon. Pl. a3 Bras. 66, 1834 nol priests ( Hook. ) Tryon, comb. nov., Alsophila conjugata Hook. Syn. , 1d eS Pate (Raddi) Copel., Alsophila corcovadensis (Raddi) C.Chr. T. crassa (Karst.) Tryon, comb. nov., Alsophila crassa Karst. Fl. Columb. 2:187. 1869. T. decom ey ee) ) Tryon, comb. nov., Alsophila decomposita Karst. Fl. eee 2:1 demi a (Morton) nee comb. nov., Alsophila demissa Morton, F eines Bot 28:7. icromatolepis (Fee) Tryon, comb. nov. Saisie dicromatolepis Fée, Crypt. Vasc. Brésil 1:1 T. elegans (Mart. ) Pres}, Alsophila elegans M T. co ) 2 T. cordata (K1.) Tryon, comb. nov., Alsophila cordata KI. Linnaea 20:441. © 1847. ~ i T. floribunda (Baker) Tryon, comb. nov., pre oe floribunda Baker, 45. 1874. Syn, Fil. ed 2, 458. T. frigida (Karst.) Tryon, comb. nov., Alsophila frigida Karst. FI. Columb. ee ep 1860. - Gardneri (Hook.) Tryon, comb. nov., Alsophila Gardneri Hook. Sp. : Scene (Fée) Tryon, comb. nov., Alsophila Glaziovii Fée, Crypt. Vasc. Brésil is 160. 1869. T. Gleasonii (Maxon) ia comb. nov., Alsophila Gleasonii Maxon, 925. T. em J (Pres!) pulley comb. nov., shania hirsuta Presl, Delic. , 190. 1822. Alsophila hiveuta (Presl) Kz T. infesta (Kze.) Tryon, comb. nov., Aiichile infesta Kze. Linnaea 9: 98. — T. Kalbreyeri (C.Chr.) Tryon, comb. nov., Alsophila Kalbreyeri_C.Chr Ind. os 44. 1905 5 (nom. seg for ee podophylis Baker, not Hook. \ uhnii (Hieron.) Tryon, comb. Nephrodium Kuhnii Hieron. Engh mary Jahrb. 34:440. 1904, Alsophila Kuhn (Hieron.) C.C pSecmeraggh oar Tryon, comb. nov., Alsophila lasiosora Kuhn, Lin- naea 36: ot T. lat sagan aes) Tryon, poets nov., Alsophila latevagans Baker, ss Bot. 19:203. 1881. A regi (Met) Tryon, comb. nov.,Alsophila Lechleri Mett. Fil. / Lech. 2:28. 1 z oar stig (Mart) Pb comb, nov., Alsophila leucolepis Mart. Icon. Pl. oye Bras Melobarrti (Brad) Tryon, comb. nov., Alsophila Mello-barretoi 1951. : a Arq. Jard. Bot. Rio Janeiro 1E22, | gor’ 46 ROLLA TRYON exiae (Copel.) Tryon, comb. nov., Cyathea Mexiae Copel. Univ. © Cait Publ Bot. 17: Se 1932. . microdonta (Desv.) Tryon, comb. nov., Polypodium microdontum ., Desv. vat bess urf, ietinds Berl. Mag. 5:319. "1811, Alsophila ‘idosotiohed (Desv.) D rT: microphylla ee Tryon, comb. nov., Alsophila microphylla Kl. Lin- ry naea 18:541. T. Miersii fe ) Tryon, comb. nov., Alsophila Miersii Hook. Sp. Fil. 1:38. 1844. T. nigra (Mart.) Tryon, comb. nov., Alsophila nigra Mart. Icon. Pl. Crypt. Ree 71. 18 in T. oblonga (KL) Tryon, comb. nov., Alsophila oblonga KI. Linnaea 18:540. T. obtusa (XL) Tryon, comb. nov., Alsophila obtusa Kl. Allgm. Garten- zeit. 30:41. pastazensis ” Hieron, ) Tryon, comb. nov., Alsophila pastazensis Hieron. 06. T. pauciflora (Presl) Tryon, comb. nov., Alsophila a Presl, Gefassbiindel aren der Farrn 35. 1847 (preprint from Abhandl. bohm. 3.1 (iaulf) KU Vinnaea 18-540. a. at online mie (C Chr. ) Tryon, comb. nov., Alsophila phalaenolepis C.Chr. Fedde Repert. 10:213. 1911 a: phemmmeneees Liook) Tryon, comb. nov., Alsophila phegopteroides Hook. Syn. Fil. 3 ries (Brade) Tryon, comb. ay , Alsophila Portoana Brade, Arch. Instit. piel Veg. Rio Janeiro 1:223. T. praecincta (Kze.) Tryon, athe nov., ‘ Alsophila praecincta Kze. Flora 1839 (1 y: Beibl. 53. De ong (Willd.) Tryon, comb. nov., Polypodium procerum Willd. Sp. Pl. 5: 206. 1 T. pubescens (Baker) Tryon, comb. nov., Alsophila pubescens Baker, Syn. Mi 449. atl na wild. ) Tryon, comb. nov., ee pungens Willd. Sp. Pl. "S 206. 1810, Alsophila pungens ( Willd. ) Pr T. rufa (Fée) Tryon, comb. nov., Alsophila is Fée, Crypt. Vasc. Brésil i: ys 1869. arginalis oe Tryon, comb. nov., Alsophila submarginalis - submar ; ae Kew Bull. ryonorum (Ri “ta Tryon, comb. nov., Alsophila Tryonorum Riba, 2 7 gare 69:66. nf aeaetes Tryon, comb. nov., Alsophila Ulei Christ, Hedwigia © vernicosa (Kuhn) Tryon, comb. nov., Alsophila vernicosa Kuhn, Lin- naea . 36: 155. 1869. T. villosa ( Willd.) T comb. nov., any: ioe Willd. Sp. PI. 5:495. 1810, Alsophila bes ( Willd). Desv 7. CYATHEA cad. Turin, 5:416, 1793. Type: Cyathea arborea fees y et sicher sat nomen 5,). THE CLASSIFICATION OF THE CYATHEACEAE 47 Hemitelia R. Br. Prod, Fl. Nov. Holl. 158. 1810. Type: Cyathea multiflora Sm. (Brown did not make any combinations for the names of the species of his new genus). Disphenia Presl, Tent. Pterid. 55. 1836, nom. superfl. Type: the same as that of Cyathea (all species, except Cyathea arborea, that were originally included in Cyathea had, prior to Presl’s publication, been removed to other genera: two species of the original six to Cystopteris and three species to Hemitelia). ormophyllum Newm. Phytol. 5:237. 1856, nom. superfl, Type: the same as that of Cyathea (Newman included Polypodium arboreum L. in his genus ). pressed, attached at one point of a pseudopeltate or peltate base, structur- dark setae, the apex rounded to filamentous; minute indument of the petiole, when present, of squamulae and (or) rarely of patent trichomidia; costa pubescent above; veins free, in lobed or pinnatifid segments the basal vein on each side extending above the base of the sinus; indusium present, scale- like to sphaeropteroid. Cyathea (Figs. 4, 10, 44-46) is an American genus of about 110 species. It is characterized by marginate petiole scales that lack a dark seta, normal, free venation (as in Figs. 42-43) and the presence of an indusium. The separation of exindusiate Trichip- teris and indusiate Cyathea has been discussed under the former genus. The petiole scales of Trichipteris, Cyathea and C nemidaria are similar in having a cellular differentiation of the margin (Figs. 39, 44-46). The central portion is of large, elongate cells with their long axis parallel to that of the scale; beyond this center the cells become progressively smaller, often more rectangular, and finally oriented approximately at a right angle to the edge of the scale. There is also usually (but not always) a transition from heavy walled and dark colored central cells to thin walled and light colored marginal cells which often gives the scale a bi- colorous appearance. Species of Cyathea with a sphaeropteroid indusium are especially numerous in the northern Andes where they seem to form a large group of closely related species. The chromosome number of n=69 has been reported by Walker (1966) for Cyathea arborea. The following list of species will serve as examples of the genus. It does not include those in which problems of taxonomy or 48 ROLLA TRYON nomenclature are known. It includes only a selection of the many closely related and inadequately known species of the northern Andean region, especially of Ecuador and Colombia. WEST INDIES C. arbore cocenite oe C. Brittoniana Max c. 7 (ork cy Domin, Hemitelia calolepis Hook. C. dissolut Cyathea aquilina aa Domin, Alsophila aquilina Christ. a (L.) S C. Lewisii pn & Proctor) Proctor, Hemitelia Lewisii Morton & Proctor. C. muricata Willd., Hemitelia muricata ( Willd.) Fée. C. parvula (Jenm. ) Domin, Alsophila parvula Jenm. C. producta Maxon. C. Sherringii (Jenm. ) Domin, Hemitelia Sherringii Jenm. C. tenera Griseb MEXICO AND CENTRAL AMERICA Cyathea acutidens — Domin, Alsophila acutidens Christ. C. aphlebioides C C. conspersa C <-C, costaricensis (Kuba) Domin, Hemitelia costaricensis Kuhn. 2.C, basen 24 Maxon C. fulva (Mart. & Gal. ne Fée, Alsophila fulva Mart. & Gal. 7/< 4 C. Jurgensenii von C. Maxo milli 6725 Gy sniatillgs ora S », Hemiteli multiflora (Sm.) Spreng. | ‘6756 C. notabilis Domi n, Alsophila notabilis — 1922, not t Saporta Mém. , Soe. Géol. France II, "8: 329. 1868. (Cocos Is.). C. onusta Christ. C. illleatead Christ. -C, suprastrigosa — Maxon, Hemitelia suprastrigosa Christ. C. Tuerckheimii M SOUTH AMERICA sheen asperata Sod. aspidiifo a Domin, Sesthes dapdllosiies Sod., not (Bl.) Moritz. ' C conde Kars' -. C, Boryana (Kahn) Domin, Hemitelia Boryana Kuhn. « _C, brachypoda Sod >) 0 C, castanea Baker, _-.¢9 (, catacampta Alston. THE CLASSIFICATION OF THE CYATHEACEAE 49 i) \\) As om pe F it y. e ee A NQN 7-1\ 3 f 4 is 2) a 3 ) ag 3 * é N: { 4) Sy ‘ Fics. 44-50. CyatHea and Cnemrparta. Fics. 44-46. CYATHEA, esto! oe eg scal : i la, Cuatrecasas 18186, US. 45, Cy. platylepis, Schultes alana Mage oe dete ae ctor $513, GH. Fies. 47-50 & Cabrera 15079, GH. 46, Apex, Cy. parvula, Proctor 551 Ss sade Cnemiparta. Fic. 47. Portion of petiole scale, Cn. spectabilis, Britton ot of chong NY. Fries. 48-50. Portions of pinnae showing venation, receptacles ae Tee bella, Hort. Lips. X 1, _ 49, Cn. speciosa, Killip & Smith 24536, X 1-1/2, GH. 50, Cn. Ewanii, Ewan 16729, X 1-1/2, US. ¢ i) e) 50 ROLLA TRYON Cc 9 ee Domin, Hemitelia obscura Mett., not Cyathea dhaiead eae ) Copel C. Copelandi Luerrs. (Ilha Trindade). C. corallifera Sod. C. decorata osetia Tryon, comb. nov., H Spite decorata Maxon, Jour. Arn. Arb. 27:439. 1946. 2 C. divergens Kze. ox pee SD C. ebenina Karst. ndosa Karst ty Me ; 22 [Cyathea fulva Sod.=Cyathea Sodiroi]. erzogii Rosens leucolepismata Alston. meridensis Karst. Mettenii Karst. microphylla Mett. muricatula Sod. nitens Sod. emitelia obscura Mett.—Cyathea columbiana]. ~ I J O iseeiavieiie Leer 3 x WT — ifolia ; petiolulata Karst. ilosa Baker. aoe nic eek) Domin, Hemitelia platylepis Hook. ° uberu eatherbyans (Morton) Morton, Hemitelia Weatherbyana Morton ( Caltneees Isls. ). 8. CNEMIDARIA Cnemidaria Presl, Tent. Pterid. 56. 1836. Type: Cnemidaria speciosa Presl. Cnemidopteris Reichenb. Deutsche Botaniker 1 (Repert, Herb. Nomencl. Gen. Pl.), Abtheil. 2:148, 235. 1841, is an illegitimate correction of the name Cnemidaria Presl. Microstegnus Presl, igure ee der Farrn, 45. 1847 (preprint from Abhandl. bohm. :353. ype: Microstegnus grandi- folius oath ) aor (Cyathea pcan a Willd. ) = Cnemidaria grandi- folia d.) Proc Hemisegta pee , Gefissbindl stipes der Farrn, 46. 1847 (preprint from Abhandl. bé 848). Lectotype: Hemistegia Kohautiana ( Pres] ) Aig = Pesci syntiewnee Presl. recat Presl, oe Stipes der Farrn, 47. 1847 (preprint G 5:355. Abha . Gas. . Type: Actinophlebia ho a ) Presl (iskeo ben horridum L. ) = Cnemidaria horrida (L.) Presl. THE CLASSIFICATION OF THE CYATHEACEAE 51 resse ch pubescent; veins forming areolae along the costa Cnemidaria (Figs. 13, 47-50) is an American genus of about 40 species. It represents a strong evolutionary line which, in the more advanced species, has developed reduced lamina architec- ture, areolate venation (Figs. 49-50), an acaulescent habit and equatorial pores on the spores. While evolution has occurred in these characters, the indusium has maintained an essentially uni- form hemitelioid form. The petiole scales (Fig. 47) are similar in cellular differentiation to those of Trichipteris and Cyathea and they are discussed in detail under Cyathea. In most species there is a relatively broad petiole scale with a dark central portion and broad whitish margins. The chromosome number of n=69 has been reported for Cnemidaria horrida by Walker (1966). The following list of species will serve as examples of the genus. It does not include those in which problems of taxonomy or nomenclature are known. WEST INDIES Cnemidaria grandifolia ( Willd.) Proctor, Hemitelia grandifolia ( Willd.) Spreng. Cn. horrida (L.) Presl, Hemitelia horrida (L.) Spreng. Cn. Kohautiana Presl, Hemitelia Kohautiana (Presl) Kze. Cn. obtusa (Kaulf.) Presl, Hemitelia obtusa Kaulf. MEXICO AND CENTRAL AMERICA : Cnemidaria arachnoidea (Maxon) Tryon, comb. nov., Hemitelia arach- idea Maxon. Contrib. U. S. Nat. Herb. 16:34. 1912 (Cnemidaria arachnoidea Underw., in synon.). ae ae n. chiricana (Maxon) Tryon, comb. nov., Hemitelia chiricana Maxon, Contrib. U. S. Nat. Herb. 16:33. 1912. bos Cn. choricarpa (Maxon) Tryon, comb. nov., Hemitelia choricarpa Maxon, Contrib. U. S. Nat. Herb. 16:40. 1912. eo : Cn. conformis (Tryon) Tryon, comb. nov., Hemitelia conformis Tryon, Rhodora 62:1. 1960. G”™ 5 ig ‘eur i 52 ROLLA TRYON Cn. contigua (Maxon) Tryon, comb. nov., Hemitelia contigua Maxon, Contrib. U.S. Nat. Herb. 16:32. 1912 (Cnemidaria conti igua Underw., in rens (Liebm.) Tryon, comb. nov., Hemitelia decurrens Liebm. / 1849. . in, decur ea "Selsk. Skr. V, 1:286. 7 QO Cn. s (Maxon) Tryon, comb. nov., Hemitelia grandis Maxon, Contrib. U. S. Nat. Herb. 16:37. 1912 Cn. mutica (Christ) ag comb. nov., Hemitelia mutica Christ, Bull. i Soc. Bot. Genéve HF 233; ook. n. rudis (Maxon) Tryon, com b. nov., Hemitelia rudis Maxon, “Contrib. A; Cn. subglabra (Maxon) Tryon, comb. nov., Hemitelia subglabra Maxon, i Contrib. U. S. Nat. Herb. 16:36, 1912 (Cnemidaria subglabra Underw., synon. ), SOUTH AMERICA Cnemidaria nero eae Tryon, comb. nov., Hemitelia abita- / uensis ee. w Bull. 1929: Cn. amabilis a so ait nov., Hemitelia amabilis Morton, Fieldiana Bot. 28:10. 195 n. bella ( Mett. ) Tryon, comb nov., Hemitelia bella Mett. Fil. Hort. Bot. Lips. 110. 1856. Cn. dissimilis (Morton) Tryon, comb. nov., Hemitelia dissimilis Morton, F nidinas Bot. 28:8. 1951. Cn. Ewani i (Alst on) Tryon, comb. nov., Cyathea Ewanii Alston, Jour. 1958. _ Wash. Acad. ‘Sei, 48:231. Cn. integrifolia (KI.) Tryon, comb. nov., Hemitelia integrifolia Kl. ee 18:539. 1844. Karsteniana (KI1.) i fa comb. nov., Hemitelia Karsteniana Kl. Allcest Gartenzeit. 20:42. 185: Cn. Lindenii tos.) Tryon Pak nov., Hemitelia Lindenii Hook. I Pl. t. 706. 1848, Cyat. tiny speciosa Willd. (not Cnemidaria~ speciosa Preel) Hemitelia speciosa ( Willd.) Kaulf. Cn. nervosa (Maxon) Tryon, comb. nov., Hemitelia nervosa Maxon, “Jour. Wash. Acad. Sci. 34:309. 1 - quitensis (Domin) Tryon, comb. nov., Hemitelia quitensis Domin, or Bull. 1929: 215. > some) Tryon, comb. nov., Hemitelia roraimensis Domin, ee Bull, 1929 Cn. speciosa ig Hemitelia th Kze. (nom. nov. for Cnemidaria speciosa Presl, not Hemitelia speciosa ( Willd) Kaulf. ). [Hemitelia speciosa=Cnemidaria Linde nii]. Cn, pase) dh (Kze.) Tryon, comb. nov., Hemitelia spectabilis Kze. a 21:233. 1848. [Hemitela subincisa=Cnemidaria speciosa]. ana (Sampaio) Log comb. nov., Hemitelia Uleana Sampaio, :65. 1923 : . Ulean: Bol. "ee Nac. Rio Janeiro 1 LITERATURE CITED Bower, F. O. 1926. The Ferns, vol. 2. Cambridge University Press Brownuie, G. 1961. Additional chromosome n umbers—New Zealand ferns. Trans. Roy. Soc. New Zealand Bot. 1:1-4, THE CLASSIFICATION OF THE CYATHEACEAE 53 CurisTENSEN, C. 1938. Filicinae (Chapter 20), Verdoorn (Ed.), Manual of Pteridology. Martinus Nijho DeWo tr, G. 1953. On the sub- division of the Cyatheaceae. M. Sc. Thesis, city pth of Malaya. Ho.ttu 1957. The scales of se ay (with special reference to eed Sm.). Kew Bull. 1957:41-45. ee . 1963. Cyatheaceae. Flora Malesia II, 1 (2): 65-176. —————— 1964. Tree-ferns of the genus Cyathea Sm. in Asia (excluding Malaysia). ape Bull. 19:463-4 oS e tree-ferns of the genus Cyathea in Australasia and \ the. Pacific, Blumea 12:241-274 aera sane , 1961. Morphology and classification of the tree-ferns. ~Phytomorphology 11:406—-420. Manton, I. & W. A. SLEDGE. 1954. Observations on the cytology and tax- sta of the boise ag flora of Ceylon, Phil. Trans. Roy. Soc. Lon- don, Ser. B, 238: 127-— Ripa, R. 1969. The pe palea a Swartziana complex ger aer eng Rhodora 71: 7-17; and Revision monografica del complejo Alsophila Swartziana Martius Ne haeny eae). Ann. Instit. Biol. Univ. Nac. ea México, 38, Ser. Bot. (1): 61-100, “1967.” Roy, S. K. & R. E. Hotrrum. 1965. Oe sin a eg I observa- tions on Metaxya rostrata (H.B.K.) Presl. Am rm Jour. 60-164. SEN, U. 1964. Importance of anatomy in the sear of we abil and their allies. Bull. Bot. Soc. Bengal 18:26—34. STEARN, W. T. 1954. Notes on some ied works. Jour. Soc. Bibl. Nat. 3-16. M. 1941. out: = Bineeieg des Cyathéacées malgaches. Bull. Franc 88:5, eters septic or ee © Fl. Madagas. Comores. 4° famille. Ame rerers 1953. Les peta alg de YAfrique intertropicale Frangaise. Mém. Instit. Franc. Afr. Noire 28. Waxxer, T. G. 1966. A cytotaxonomic survey of the Pteridophytes of Ja- maica. Trans. Roy. Soc. Edinb. 66: 169-237. A MONOGRAPH OF THE FERN GENUS ERIOSORUS! ALICE F,. Tryon Eriosorus, a genus of tropical American ferns, is perhaps more familiarly known under the older name, Gymnogramma, stem- ming from Hooker’s Synopsis Filicum (1868) which included nearly a hundred species. Underwood (1902), in his series on genera of American ferns, attacked Hooker’s treatment as “the most unaccountable and unnatural collection of misfits that ever figured in the pages of a treatise on systematic botany.” Although Hooker's treatment was indeed unnatural, Underwood's criticism was unduly caustic since Hooker did divide Gymnogramma into six sections, and the species now under Eriosorus were, for the most part, treated under Eugymnogramma. The following is an account of publications treating significant groups of the species now in Eriosorus, as well as the most useful and recent generic classifications. The essential data on the tax- onomic history of each of the species are found in the synonymy. As with much of systematic botany, the initial critical work came from Sweden. The first handbook of ferns by Olof Swartz (1806) included Grammitis cheilanthoides from Tristan da Cunha (erroneously reported from Mauritius). Documented specimens from these islands were made by Aubert du Petit-Thouars in 1793. In the text of his work, Petit-Thouars (1808) described the species as Asplenium filipendulaefolium, but the illustration is named Grammitis cheilanthoides Sw. Apparently Petit-Thouars learned of the earlier name while his work was in preparation. Studies of American tropical plants were greatly stimulated by the explorations and publications of Alexander von Humboldt: Near Caracas, Venezuela, he and Bonpland collected two species of this group. These specimens were classified by Nigaise Desvaux (1827) under the new genus, Gymnogramma. He combined them with the earlier species described by Swartz, in the genus Gram- mitis, on the basis of the sporangia without indusia disposed along the veins. Unfortunately, he also included Gymnogramma rufa (L.) Desv., which is the type of the earlier genus Gymno- pteris, thus Gymnogramma is now considered to be a superfluous name, as has been already noted by A. Tryon (1963). Specimens, from the rich collections sent from Ecuador to Kew +The work has been supported by National Science Foundation Grant GB-1693. A MONOGRAPH OF ERIOSORUS 55 by William Jameson, were the basis for the new genus Jamesonia, described by William Hooker and Robert Greville in the Icones Filicum (1827-1831). Shortly after proposing this genus, they described two new species under Gymnogramma, based on the Jameson collections, and these are now considered to represent hybrids involving Jamesonia. Eriosorus was proposed by Antoine L. Fée (1852), not as a replacement for Gymnogramma, but as a new segregate genus. On the basis of many approximate and mostly confluent sori, it it was included with Jamesonia and five other genera under Polypodiaceae, subtribe Cheilantheae in the group Eucheilan- theae. Eriosorus rufescens (as Gymnogramma) was proposed in the same work and included in subtribe Hemionitideae, in the group Leptogrammeae which also included Pterozonium, on the basis of the sori being equivalent in number to the veins. Ano- gramma was also treated in the same publication, and under this name Fée proposed a new species of Eriosorus as Anogramma Ottonis. Thus, Eriosorus was first presented, in a restricted sense but with several species now recognized as belonging to it, under two other genera. Gustav Kunze combined Gymnogramma under Jamesonia, and noted the similarities of the genera in the detailed description of Jamesonia hispidula in his Farrnkraiiter (1846). This concept was reversed by Georg Mettenius in his floristic treatment of the Filices (1864) in which he used Gymnogramma and placed Jamesonia in synonymy. This early work on the Colombian flora was elab- orated by Herman Karsten (1857-1869 ). He treated seven species under Gymnogramma, based on his own collections and field observations. His specimens from the vicinity of Bogota represent some of the difficult variant forms which now appear to be hy- brids. The most complete study of those species now included in Eriosorus was made by Maximilian Kuhn in his work on the Chaetopterides (1882). Both Jamesonia and Eriosorus are in- cluded under Psilogramme, the former under subgenus Jamesonia and the latter under Eupsilogramme which included 24 species, 16 of which are recognized here. Lucien M. Underwood (1902) followed this use of Psilogramme in his review of Hooker's application of the name Gymnogramma. The name Psilogramme was also used by William R. Maxon in his work on the North American species (1915). Edwin B. Cope- 56 ALICE F. TRYON land revived the earlier name, Eriosorus, in his Genera Filicum (1947) as being a genus of 35 species, 14 of which he lists. This name has been followed since then, as in the study of the species in Costa Rica by Edith Scamman (1962), and in the work on the Ferns of Peru by R. Tryon (1964). I prefer to follow Carl Christensen’s classification ( 1938) of the Polypodiaceae until more facts are known about the relationships of the families. In this, Eriosorus (as Gymnogramma) was placed in the subfamily Gym- nogrammeoideae, the tribe Gymnogrammeae and in the group of the Chaetopterides which includes Jamesonia, Pterozonium and three other genera. In the most recent classification by Rudolfo E. G. Pichi-Sermolli (1966) Eriosorus is included in the new family Hemionitidaceae, between Pterozonium and Jamesonia, in the tribe Jamesonieae with four other genera. A larger group of genera, including Pityrogramma and Anogramma are treated in the tribe Hemionitideae. On the basis of this study and that of Jamesonia (1962), as well as the work on the related groups, Pityrogramma and Anogramma, by Rolla Tryon (1962) and of Pterozonium by David Lellinger (1967), it appears that Eriosorus represents the least advanced element among these five, mainly American, genera. Eriosorus, Jamesonia and Pterozonium form a closely related group on the basis of many similarities such as the pattern of venation, soral arrangement, alignment and structure of the sporangium, indu- ment and spores. In these characters they are sufficiently distinct from the Old World genera Syngramma, Craspedodictyum and Taenitis to represent an independent evolutionary line. Ano- gramma and Pityrogramma are not as closely related but similari- ties of the sorus, sporangia, spores and lamina indument indicate that they can be associated with the previous three. Several cyto- logical reports for these genera have established a base number of x =29 for Anogramma, which is the same as that here suggested as the base number for Jamesonia and Eriosorus on the basis of hexaploid or higher counts. From a number of counts, Pityro- gramma appears to have a base number of x=30. However, the recent report by Walker (1966) of n—=58 for Pityrogramma tri- foliata (as Trismeria) in Jamaica, along with evidence for hybrids between this and Pityrogramma as proposed by Rolla Tryon (1962) suggest that Pityrogramma has base numbers of both 29 and 30. A MONOGRAPH OF ERIOSORUS 57 Eriosorus is regarded as the least advanced among these five genera as is evident from the less elaborated spore sculpture, the simple form of rhizome indument, unspecialized leaf form in several species and in the spathulate form of the gametophyte. There is a close relationship between this genus and Jamesonia and it is apparent that the latter has been derived from more than one element in Eriosorus. The relationship to Pterozonium is not as Close and is without clear lineal derivation. ACKNOWLEDGEMENTS Collections er re studies of these plants were made with Rolla Tryon, the earliest in while hunting Jamesonia in Venezuela and Colombia We jie 7 a and also tree ferns in Brazil in 1965. It was our special pleasure to meet the eminent collector and botanist of that country, Dr. Brade, who generously shared his knowledge of Eriosorus localities of Mt, Itatiaia. In Sao Paulo, Dr. Alcides Teixeira, Director of the Ins anetts e Janeiro. te) Her pies anum, generously sR assistance in obtaining material near og Fs e Fields studies in Costa Rica were facilitated by the Organization for Tropical Studies and i the University of Costa Rica through the kindness of Dr. gee : gh Rodri In of type material in European herbaria, J. A. nege of es Brith Muse helped me with locations of Alston’s Nee De rmy generously Settimicteatcd the pee of the Seon Electron Microscope ne = age useum and a sample of Eriosorus spores was examined. Dr. M. Jarrett and F. Ballard eS volta ies data relating to the jee te and Baker specimens at K M. Tardieu-Blot and A, Lourteig located types among the rich cc hg in this group at the Muséum ae erga Naturelle in Paris. Prof. T. epee eas of in ays. + am parti cula cy inde sy “ Dr. he s A icosmene dass his prsecemglel 58 ALICE F. TRYON My sincere thanks are extended to the curators of herbaria cited for loan of specimens for extended study. Abbreviations of herbaria follow pee : y : : ite from a and César Vargas and John Wurdack from Peru. Particular thanks are made to Timothy Plowman for splendid cytological material from Mt. Itatiaia and to John Mickel for collections of special interest from Mexico. The art work enhancing the study was done by Marjory Markel and final typed draft with much editorial pee ay For lively discussions of problems relating to these plants and innumerable kindnesses, I am grateful to Gerald Gastony. For his generous counsel and poset attention on many matters of the study, I am most indebted to Rolla ryon. EVOLUTIONARY TRENDS Eriosorus represents a relatively old group among genera of the Polypodiaceae. This is made evident by the occurrence of exindusiate sori which follow the veins, spathulate gametophytes, a high polyploid level, a fossil record of the spores and a broad geographic range. Hybridization appears to have obscured the broader lineal evolutionary relationships in the genus. Most of the species can be associated in groups of two or three closely allied members as shown in Fig. 1. This chart summarizes the species groups, the major levels of specialization and also affinities with other genera. More detailed relationships are noted in the species treatments and in discussions on the cytology, geography and morphology. Associations that can be most clearly established are indicated by heavy lines. The species groups are arranged in three levels: those at the lowest, most generalized level have well developed elongate-triangular leaves, simple rhizome trichomes and deep brown spores; the highest level shows two major trends in special- ization of the leaves—complex, scandent ones and compact, linear forms; the central level consists of groups intermediate to the two extreme ones. The most generalized level is best represented by Eriosorus myriophyllus and E. congestus with their unspecialized leaves, simple rhizome trichomes and deep brown spores. Eriosorus A MONOGRAPH OF ERIOSORUS 59 Sellowianus is close to the former species, but has more constricted leaves and is confined to drier sites in Minas Gerais. The above three species are geographically peripheral to the main Andean center of the genus. The broad range of E. myriophyllus in Brazil, at the lowest altitudinal range for the genus, suggests a possible center here prior to Andean speciation. The occurrence of E. con- gestus in Costa Rica suggests an earlier migration of an unspecial- ized form northward from South America. Hexaploidy in this species and in E. myriophyllus shows that a high polyploid level has been attained in these generalized species. At the intermediate level, no strong association can be estab- lished between the five main species groups. Affinities within the groups are indicated by heavy connecting lines on the chart. There are especially close relationships between E. hirtus and E. his- pidulus as shown by similarities in leaf architecture, black rhizome bristles and tan spores. The group of E. aureonitens-accrescens- Stuebelii is characterized by dense tomentum on the leaves. Relationships in this group may be complicated by hybridization because the species occur together and the latter two have ir- regular spores. The group of E. Wurdackii-insignis-Orbignyanus SPECIALIZED nen JAMESONIA Pie | ~ 7'¢ CHEILANTHOIDES* EWANII ff 4 ee sciias ‘jeilaiaacha BIARDII HIRSUTULUS SETULOSUS FLEXUOSUS GLABERRIMUS i Hesies ne enoce One HS ENS PTEROZONIUM ————__1 STUEBELII VELLEUS ORBIGNYIANUS ,” , ACCRESCENS WARSCEWICZII HISBIDULUS INSIGNIS | if LJ rT AUREONITENS NOVOGRANATENSIS PAUCIFOLIUS HIRTUS WURDACKII? Loans CONGESTUS MYRIOPHYLLUS GENERALIZED adil Fic. 1. Chart of the evolutionary trends. The taxa arranged as noted under that topic in the text. 60 ALICE F. TRYON has similar sori, restricted to marginal bands and pinnae departing from the rachis at angles greater than 90 degrees. Eriosorus Wurdackii is the least specialized of this group and supplies a link with this genus and Pterozonium. Relationships with Pterozonium are shown in several characters, such as the sub-marginal sori, firm pinna texture, deep brown trichomes confined mainly to the sorus, and vein ends terminating short of the margin. Pterozonium reni- formis and P. brevifrons, two of the most widely distributed species, occur in northern Peru, and the latter has been collected by Wurdack in the same area as Eriosorus. There are two trends in leaf form among the most specialized species. The scandent one is best represented by Eriosorus flex- uosus. The broad, black rhizome bristles and light tan spores also show specialization in characters other than the leaves. Eriosorus flexuosus is one of the most dynamic species ecologically, as shown by its broad geographic distribution and wide altitudinal range. It occurs with Eriosorus Biardii in Brazil and appears closely allied to it because of similarities in the fractiflex rachises and slender, bifurcate ultimate segments. Erisorus Ewanii is a remarkable species, also close to E. flexuosus. It represents an intermediate between the scandent and linear-leaved forms, but exhibits several unique characters as noted in the species discussion. The second evolutionary trend at the most specialized level is the reduction of the leaves to linear forms. It is from this group that Jamesonia has evolved, and here there are no clear morpho- logical disjunctions between the genera. There are several hybrids and variants, noted in the species treatments, which involve Jamesonia and Eriosorus. Eriosorus cheilanthoides is geographi- cally the most dynamic species of the linear-leaved group with the widest distribution in the genus, reaching the most remote island in the South Atlantic. Its relationships to other 1-pinnate species, such as E. hirsutulus and E. Lindigii, are not clear, but these may be involved in hybridization with E. cheilanthoides at the lower polyploid levels. These species are involved with Jamesonia, and variants implicating Jamesonia imbricata, J. rotundifolia and J. bogotensis are noted in the species treatments. A second series of linear-leaved species that represents another independent connection with Jamesonia includes E. setulosus and E. longipetiolatus. They are related to E. rufescens at the inter- mediate level of specialization, and to a group of species allied to J. verticalis. A MONOGRAPH OF ERIOSORUS 61 GEOGRAPHY Morphological diversity within this genus suggests that the amount of evolution involved has required considerable time. A few fossil records of the spores document its occurrence in the Pleistocene and possibly the Oligocene. Spores of Eriosorus cheilanthoides were described from peat cores on Tristan da Cunha and Gough Island in the South Atlantic by Hafsten (1960). On Tristan these are at the lowest level of the core, below 2.8 m. and two levels above this. On Gough Island the record is more continuous from 4.3 m. up to 0.3 m. This profile was correlated with a radio-carbon-dated monolith, dated at 4720 + 130 B. P. Eriosorus spores are found below this dated level and thus have probably existed there for at least 5000 years. Hafsten’s excellent photographs of subfossil spores from 3.5 m. on Gough show the prominent equatorial flange with projecting angles characteristic of modern material. Similar spores are identified by van der Hammen and Gonzalez (1960) as Jamesonia but these cannot be distinguished from those of Eriosorus. These samples were taken near Bogota, Colombia and the lowest level represents Pleistocene deposition. The base of the core was C,, dated at 21,900 (+ 600 ) B.C. and was interpreted as the last part of a cold phase, probably of the Wiirm stage of the Pleistocene. The profile shows a nearly continuous record of these spores from the lowest level at 32 m. up to near the surface. They are the most abundant spores of the pteridophytes included in their sample, except for “Cyatheaceae,” and suggest that these plants were flourishing during most of the period. The photographs certainly represent either Eriosorus or Jamesonia spores. At the present time both genera are frequent in the vicinity of the Sabana de Bogota and it is quite possible that the spore sample may represent a mixture of both. A single spore of Jamesonia is reported by Briggs and Graham (A. Graham, pers. comm. 1969) from the San Sebastian formation in Puerto Rico and is dated Middle Oligocene. If it can be identified as this complex with certainty, it more likely represents Eriosorus which is known from the Luquillo Mts. in Puerto Rico. The evolutionary development of Eriosorus and its broad geographic range do imply a considerable period of development and a mid-Tertiary record would not be unexpected. The geographic distribution of the species also provides some information on the evolutionary history of the genus. The species 62 ALICE F. TRYON 1. Distribution of Eriosorus and graph of altitudinal ranges. Map oo 1000 P foot contour in outline, inset of South pein islands, Tristan da Caske 3200 se. - tea Gough 352 km. of Tristan. Altitudinal ranges at 200 m. cake be. 4200 m. the taxa abceeiaed ae the first two or three letters, the varieties by a dash and the aa letter. A MONOGRAPH OF ERIOSORUS 63 are mainly in cool, moist highlands. The general range is shown on Map 1 with the 1000 foot (305 m.) contour in outline. The altitudinal range is between 600-4200 m. The graph accompany- ing the map shows altitudinal ranges of the species. The altitudes are usually expressed as ranges on the collections and the whole range is arbitrarily incorporated in the bars for each of the taxa. More than half of the taxa occur above 2200 m. and only three are wholly below 1800 m. The general geographic range of Eriosorus extends from Santa Cruz in central Bolivia, north along the Andean Cordillera and Central American highlands to the high pine-oak forest in Guer- rero, Mexico. In Venezuela, it occurs from the Sierra Nevada east- ward along the mountains bordering the Caribbean to Sucre. It is disjunct on several of the sandstone massifs in Venezuela and on Roraima in British Guiana. In Brazil, the genus extends from Minas Gerais south in the highlands to Cerro Largo, Uruguay. Species of the genus are known in the Lesser Antilles in Dominica and also in the Greater Antilles in Cuba, Hispaniola and Puerto Rico. The most disjunct stations are in Tristan da Cunha and Gough, some 2000 miles east of South America. The species are concentrated in Brazil, the Andes and Costa Rica. Of the six Brazilian species, four endemics are relatively wide-ranging in southeastern Brazil. Of these, Eriosorus myrio- phyllus is most widely distributed and occurs at 600 m., the lowest altitude reported for the genus. Eriosorus Sellowianus is a more specialized form, restricted to Minas Gerais. The other two en- demic species, E. Biardii and E. insignis, are also more specialized and are more closely related to the Andean species than those of Brazil. Eriosorus flexuosus and E. cheilanthoides, the two species representing the most specialized forms in the genus and those having the widest geographical range, are confined to single stations at high altitudes in Brazil. They are considered to be more recent migrants than the above-mentioned Brazilian species, and are found in the Andean region. Eriosorus cheilanthoides certainly arrived on Tristan by long distance dispersal from east- ern Brazil after the last half of the Pleistocene when the island was first available for colonization. This also suggests that the species might have migrated across the continent from the Andes in the same manner. ne The largest concentration of species, including 19 taxa, 1s the Andean region. Ten of these occur at high altitudes, mainly above 64 ALICE F. TRYON 3000 m., and most of them have reduced, linear leaves and local ranges and five of them are endemic in Colombia. They are exem- plified by Eriosorus longipetiolatus, which has very reduced, jamesonioid leaves. This species occurs on two islolated paramos of southern Colombia in conjunction with species of Jamesonia and E, setulosus from which it is possibly derived by hybridiza- tion. In the Andes of Peru there are three endemic species, each occurring in the north around Chachapoyas. Eriosorus Wurdackii is known only from there and E. Stuebelii and E. accrescens appear again in the southernmost department of Puno. The concentration of species with reduced leaves at high alti- tudes in the Andes represents more than one evolutionary line. A group of six species with large, scandent leaves is also mainly Andean. The latter occur at a lower altitude, have greater alti- tudinal range and represent different evolutionary elements. Specialized characters such as glandular, tomentose or coriaceous conditions of the leaves or light colored spores are also derived features of Andean species that have moved north into Mexico and east into Venezuela. This diversity of forms in the Andean region may reflect the considerable climatic fluctuations which occurred during the Pleistocene. The Central American species are mostly concentrated on the higher volcanos of Costa Rica. The four species which occur there are more Closely related to South American species than to each other. Eriosorus congestus, the most frequently found, is usually very abundant at lower altitudes than the others in Costa Rica. from Costa Rica. Their disjunct ranges suggest that they were past. A MONOGRAPH OF ERIOSORUS 65 There are no strong phyletic lineages evident in this genus as have been shown in other groups in the American tropics such as Pellaea, Doryopteris and Lindsaea. There are aggregates of two or three closely related species without strong connections be- tween them. The morphological diversity and disconnected elements in Eriosorus can probably be correlated with the pronounced climatic and ecological changes that occurred, particularly in the Andean region, during the Pleistocene. The fluctuations during this period would be effective forces influenc- ing the migration, isolation and extinction of populations and would also provide the environmental conditions for hybridization which is characteristic of the genus. Observations at sites where Eriosorus occurs in montane areas of Costa Rica and Colombia show that conditions suitable for hybridization are produced where man has been active in eliminating the forests by burning and lumbering. CyTOLocyY The existence of both 6-ploid and 12-ploid chromosome num- bers proves that polyploidy occurs in Eriosorus. The presence of plants with ca. 174 largely unpaired chromosomes at meiosis shows an intermediate condition between the two polyploid levels. It demonstrates a stage prior to doubling of chromosomes in the sequence which has resulted in high chromosome numbers in this genus. The illustrations of meiotic cells, shown in Fig. 2, and the chromosome numbers included in Table 1, were obtained from young sporangia, prepared in the field, in a standard fixative of 3:1 alcohol and glacial acetic acid. These were stored under refrigeration from one to six months, and then stained in aceto- carmine, as described by Manton (1950). Photographs were made from these preparations which were made permanent by freezing with solid CO,, and mounted in diaphane. The cytological records for Eriosorus and Jamesonia, including literature records, are summarized in Table 1. : The prevalence of morphologically discrete species in Eriosorus and those in Jamesonia with meiotic chromosome numbers of 87 suggests that these levels have been attained in a uniform system. e number is regarded as representing a hexaploid level and may possibly be derived from other genera at lower levels. How- ever, on consideration of the wide diversity of morphological ALICE F. TRYON 66 fo or, ¥ ¥ ee Oo, ” 4 4 bh lag as : } 2 ~ oF « ; . \ Fic. 2. For legend, see opposite page. A MONOGRAPH OF ERIOSORUS 67 types, particularly among the Andean species, and the record of two ploidy levels within the genus, it seems likely that the lower levels may still be found among the Andean species. The meiotic chromosome number of 174 for Eriosorus cheilan- thoides was first reported by Manton & Vida (1968) and was in- terpreted by them as 12-ploid. They regarded this unusually high number in the Tristan plants as confirmation of Christensen’s view that the species is an endemic on those islands. They also noted the special need for an examination of Andean plants, which I had regarded (A. Tryon, 1966) as similar to those on Tristan. The chromosome count presently reported from a collection of E. cheilanthoides from Mt. Itatiaia, the highest peak in eastern Brazil, as n=174 confirms the close relationship of the Tristan plants to the continental ones. On Itatiaia, E. cheilanthoides grows in close association with Jamesonia brasiliensis and there are spe- cimens intermediate between these species. Cytological fixations of these unfortunately did not yield definitive results. This dodeca- ploid level of n=174 apparently has been derived from a lower hexaploid and the latter from doubling of the triploid stage. In turn, the triploid has undoubtedly originated from crosses be- tween the diploid and tetraploid which are based on the mono- ploid, x=29. This scheme is supported by the independent interpretation by Manton & Vida of E. cheilanthoides as a 12-ploid based on x=29, which they made prior to the discovery of hexa- ploids. The high somatic chromosome number, 2n=348 in E cheilanthoides, supports its disposition as a derived species as shown in several morphological characters noted elsewhere. A precise count could not be determined for Eriosorus myrio- phyllus from Brazil, but from the general volume of paired chromosomes in meiotic cells the number seemed to be on the order of a hexaploid. Cytological investigation of this species, which grows at relatively low altitudes, is of interest since it represents the most generalized form in the genus. In my revision of the genus Jamesonia, J. bogotensis from Paramo Chisaca in Colombia was reported as n=—87 at meiosis. The present report of the same number for J. Scammanae from Fig. 2. Photographs of chromosome squashes from permanent acetocarmine ere a of first meiotic divisions (see Table 1 for counts and ploidy levels, Fig. 3 for diagrams). Jamesonia Scammanae, Rodman 21a, X 660; b, Eriosorus Warscewiczii, ah Tryon 7003 30; c, E. War ii X Jamesonia Scammanae, Tryon & Try e 048 1060; d, E. fleruosus var. fleruosus, Tryo ryon 7014, X hens glaberrimus, Tryon & Tryon 70 00; f, E. flexuosus & «Sagas Eigen 6 : x : ryon 7011, X 1060; g, E. congestus, Tryon & Tryon 7044, cheilanthoides, Plowman 2840, X 660 TABLE 1] CHROMOSOME NUMBERS OF ERIOSORUS & JAMESONIA Ploidy Collection Locality Species Number a congestus ” See ‘a -- ) 87" 87 87" 87"! E. cheilanthoides 174" (Fig. 2h, 3f) oe E. flexuous 87" ( Fig. 2d, 3d) 87 E. aaa S7" (F ig. 2e, 3c) II E. myriophyllus ca. 87 E. Warscewiczii 87" ( Fig. 2b, 3b) ic 87 E. op eiag x E. Warscewiczii ca. 174" (Fig. 2 E. ee x J. Scammanae ca. 174! (Fig. 2c Jamesonia bogotensis ST" J. Scammanae 87" ( Fig. 3a, 2a) 87! Tryon & Tryon 6997 (cH) Tryon & Tryon 7045 (cH) Tryon & Tryon 7063 (GH) en & Tryon 7044 (cH) Se : ee oe ed (cH) Plow 2840/ 5140 fee ickson 1 aa & Vida 1968 ) Tryon & Tryon 7014 (cH) Tryon & Tryon 7016 (cH) Tryon & Tryon 7061 (cH) Tryon & Tyron 6745 (cH) Tryon & Tryon 7003 (cH) Tryon & Tryon 7017 (cH) Tryon & Tryon 7050 (cH) Tryon & Tryon 7011 (cH) Tryon & Tryon 7048 (cH) Tryon & Tryon 6178 (cH) Tryon & Tryon 7047 (cH) Rodman 21a (cH) Costa Rica: Prov. Heredia Vara Brazil: Rio de Janeiro Mt. Itatiaia South Atlantic, Tristan a Cunha Costa = Prov. Alajuela olca che Algsaele: Volcan Pods Cos shire Prov. San Jose L Pa Im Brazil: Rio ge Janeiro, near Palm Costa Rica: = Alajuela, Volcan Pods Prov. Alajuela, ‘hiss Poas Prov. an rtago, Cerro de la “So Rica ei Alajuela Volcan Costa hie Siew, Cartago, Cerro de la Muerte Colombia: Dept. Cundina- marca, Paramo de Chisaca Costa Rica: Prov. Cartago, Cerro de la Muerte Prov. Cartago, Cerro de la Muerte NOAUWL “A AOLIV A MONOGRAPH OF ERIOSORUS 69 Costa Rica suggests that in Jamesonia, as well as in Eriosorus, species may have stabilized at the hexaploid level. The hybrids discussed in this work are proposed with confi- dence in two cases where the putative parents and intermediate a * b e *2 ° “ae Pe wo 7 ad cette Srre_ Sih: Seiad 2 eg, tale Dee “has ge itt, a OE ee” + OR eS see a Jo + & #.+ + os + ° > © Bg ~ v xe te / of Fe OO! eo +y,47 x + Or 2 + sawv a eo, & FS pt gee Uh, Mian 6, ’ ¥G x Ft) 4s aad a at w rf oo Pd “if j $ * = L Ti ag VIN a fe 3» vy tet e + se + see Ho, eae Pee + %, ttt 7 xara < x ¥ Be, ° 5 "vf + es f + x +%4o Gt t+ yo oe + a& ¥ Ms co dow wage GSR be ER Pai +e +? x A AEt5r¥ & 9 gh tie 3 at %s Fates «8S ae 52 aT OF ie we or a es ~* Me at 9g *y x x SN etet © res 7 Fic. 3. Explanatory diagrams of species in Fig. 2 showing bivalents in focus in black and the remainder in outline; from th xcept Jamesonia. a, n= 87; b, Eriosorus Warscewiczii, n=87 ; c, &. glaberrimus, n=87; 4d, flexuosus var. flexuosus, n=87; e, E. congestus, n=87; f, E. cheilanthoides, n=174. ty 70 ALICE F. TRYON forms are known in the field and have been cytologically exam- ined, Several other putative hybrids are proposed which have not been cytologically studied but are morphological intermedi- ates that can be associated with species occurring in the same habitat or geographic range. Other intermediate collections, noted as variants under the species, are tentatively proposed as hybrids in the hope of providing a useful guide to field work on these complexes. The record of the two hybrids with 174 largely un- paired chromosomes at meiosis, from plants which are morpho- logically intermediate, indicates that hybridization precedes doubling of the chromosomes. The following observations on the gametophyte and the ecology of the plants are pertinent to hybrid- ization. The gametophytes of Eriosorus insignis produced abun- dant mature antheridia (Fig. 4) prior to archegonia. This sequence is suggestive of an adaptation promoting outcrossing and, under suitable conditions, hybridization. The numerous intermediate forms between species of Eriosorus and Jamesonia suggest that the integrity of the species in these genera is not so much main- tained by genetic incompatibility as it is by the habitat and ecology of the species. Field observations were made and reported by A. Tryon (1968) on populations in relation to cytological sampling for the Costa Rican species. Eriosorus congestus is the widest ranging species of the genus in Costa Rica. There are abundant plants in cut-over pasture land at La Palma and there are also plants of E. glaber- rimus on the few remaining trees. A collection from this locality was morphologically intermediate between the two species al- though it resembled the latter more closely in its scandent habit. Unfortunately its sporangia were too mature for cytological study. However, the spores were aborted and on the basis of this, the intermediate morphology of the plant, and the association of the species at this locale, the specimen is considered to be a hybrid of E. glaberrimus and E. congestus. On Volcan Poas there are numerous plants of Eriosorus flexuo- sus below the crater and they are especially conspicuous growing among litter remaining after lumbering. This species was also abundant on shrubs nearby in the road clearing with numerous plants of E. Warscewiczii. One collection from this site was mor- phologically intermediate between the two species, although it resembled E. flexuosus more closely in its scandent habit. The cytology of this plant clearly showed 174 largely unpaired chrom- osomes at meiosis. A MONOGRAPH OF ERIOSORUS WZ In the paramo of Cerro de la Muerte, Eriosorus Warscewiczii occurs at 3150 m. with Jamesonia Scammanae and there are inter- mediates between these species with ca. 174 largely unpaired chromosomes at meiosis. Similar specimens from Chirripo Grande were described as Gymnogramma Kupperi. The reduced, linear leaves of these hybrids resemble those of plants in the Andean E. cheilanthoides complex, which also involves Jamesonia hy- brids. The Costa Rican intermediates and those of the Andes involving Jamesonia are difficult to identify without information on the species-association and on the cytology, because the Jame- sonia characters strongly mask those of the Eriosorus. GAMETOPHYTES There does not appear to be a previous record of gametophytes for the species of Eriosorus which are included here. Their spath- ulate form is uncommon in the Polypodiaceae and they are also of special interest because of marked resemblances to the gameto- phytes of the Schizaeaceae. Spores of three species were germinated in clay pots on steril- ized soil with a top dressing of pot chips. The sequence of devel- opment was followed for about five months in Eriosorus insignis from Brazil (Tryon ¢ Tryon 6701) and a shorter time for two other species, E. hirsutulus and E. hispidulus. The cultures were unfortunately lost by accidental flooding. Several stages in their sequence of growth (see Fig. 4) were traced with the use of a microprojector. The spores of E. insignis germinated about four- teen months after they were collected and those of E. hirsutulus, collected in 1961, were still viable after five years. In E. insignis and E. hispidulus, many of the gametophytes form a two-rowed filament by lateral cell division prior to the formation of the thallus plate. In E. hirsutulus, the single cell filament persisted more than a month after germination. In Eriosorus insignis, the two-rowed forms are apparent at seven weeks and, as shown in Fig. 4d, they extend to the spore. The apex persists as a single, unusually attenuated papillate cell. There are numerous, coarse, tan rhizoids, often two or more per cell, especially on the lower portion of the filament, a dense mat of which obscures the structure of the lower part of the gametophyte. Thus only a few rhizoids are included in the drawings. Early stages in plate initiation are evident at seven weeks and the spath- ulate form is well developed by eleven weeks. Series of cells, differ- 72 ALICE F. TRYON eee lez 2 OOD A SENHA Yer A) RNY ee “0 () ARON NS I) 4 OS EEN Gh CBR se “i bycee, BO WKY BL BO N x Hye Jd ie. eo= Fic. 4. Gametophytes with some rhizoids and attached spores, a-g, Eriosorus insignis: a-d, at seven weeks, e, at eleven weeks with antheridia, f, at five months, with some antheridia and lateral meristem at left, all 45, g, antheridium, Tryon & Tryon 6701 (GH); h-j, E. hispidulus, at seven weeks, & 45, Gastony 11 (GH); k—m, E. hirsutulus, at eleven weeks, X 60, Tryon & Tryon 5922 (GH). entiated from a lateral meristem, are clearly evident by this time and also some antheridia on the lower portion of the thallus. The broad, spathulate form of the gametophyte was maintained in these cultures for a period up to five months. There were abun- dant, mature and dehiscent antheridia at this time but no arche- gonia were produced. The three-celled antheridia, shown in Fig. 4g, consist of a short, basal cell below the larger, cylindrical one. The antherozoids are tightly packed and appear to push a funnel- shaped core into the central region of the basal cell. There are few, ca. 20-30, massive antherozoids. The single cap cell of the anther- idium dehisces and the antherozoids are released singly through a pore, with the surrounding cell wall forming a spout-like lip. The production of antheridia and absence of archegonia in these gametophytes after five months, suggest that they are adapted to a system of outcrossing. Such a system would be most effective in the formation of the intermediate specimens of plants, regarded as hybrids between species. A discussion of this will be found under several of the species. Gametophytes of Eriosorus hispidulus, Fig. 4h-j, from Puerto Rico (Gastony 11) and E. hirsutulus, Fig. 4k-m, from Colombia A MONOGRAPH OF ERIOSORUS 73 (Tryon & Tryon 5922) were grown and seemed to develop more slowly but were observed for a shorter time than E. insignis, Fig. 4a—g. Their general shape was similar to E. insignis but no antheridia were apparent after three months. An asymmetrical thallus with a persistent lateral meristem is reported for Anogramma, and in Pityrogramma it later becomes asymmetrical-cordate as reported by Momose (1964). Thus, an affinity between Eriosorus and these two genera is suggested by similarities of the gametophyte as well as the sporophyte. The early lateral divisions of the filament, the spathulate shape and lateral meristem in older forms are similar to comparable stages in Mohria, and especially in Anemia, both of the Schiz- aeaceae, studied by Atkinson (1960, 1962). These similarities are suggestive of broader relationships of Eriosorus with that family, and perhaps a closer affinity to it than to genera having wholly cordate gametophytes among the “Gymnogrammoid ferns” in the Polypodiaceae. MorPHOLOGY AND ANATOMY There does not appear to be a comprehensive morphological and anatomical study of this genus. Dunzinger (1901), a student of Goebel, wrote a thesis on the morphology of Gymnogramma with many illustrations of the spores. In it, the spores are de- scribed for six species which are included here in Eriosorus. Bower (1928) included the latter under Gymnogrdmma, which was one of nine genera forming a central group of gymnogram- moid ferns. This group was characterized by stelar systems based upon the solenostele without medullary strands and marked by perforations dividing the leaf into two vascular bundles. The vascular system in the rhizome of Jamesonia was described by Bower as a slender solenostele with alternate, elongated leaf gaps and Jamesonia was included in a more primitive, primary group of gymnogrammoids. . On the basis of the morphological and anatomical similarities of the rhizome, and on other characters noted in the following discussion, the relationship between Eriosorus and Jamesonia appears to be a close one. In Eriosorus as well as Jamesonia, the amphiphloic siphonostele with dictyostelic stages represents an intermediate stelar state between an intact cylinder and a dis- sected dictyostele with many strands. 74 ALICE F. TRYON A morphological and anatomical survey of all of the species included in this treatment would be too lengthy to present here. However, detailed studies have been made of two of the species which represent distinct morphological forms. They are Eriosorus myriophyllus [Tryon and Tryon 6745 (cH)] collected near Pal- mares, and E. cheilanthoides [Tryon and Tryon 6724a (cH)] from Mt. Itatiaia, both in the state of Rio de Janeiro, Brazil. Although these may not be representative of all the species, they may serve as examples for the genus and the following general discussion of morphological and anatomical structures is based mainly on them. Eriosorus myriophyllus has a compact rhizome which is larger and less strongly repent than most species. The rhizome in E. cheilanthoides is slender, elongate, repent and more characteristic of the genus although the leaves are 2-pinnate and represent a reduced form, Other morphological aspects of the plants such as indument, epidermis, sporangia and spores are more broadly surveyed to include characteristics of these struc- tures which bear on ideas concerning the evolution and phyletic position of the species. Methods. Specimens were treated according to the techniques outlined by Metcalfe (1960) with modifications as noted. The rhizomes and petioles were boiled and softened in water prior to storage in 70 percent alcohol. Sections were cut between pith on a sledge microtome and cleared in 25 percent hypochlorite solu- tion (Chlorox) for 10-20 minutes. In doing this, the tissue becomes clear and is restored to near fresh condition and requires a shorter time and a less concentrated solution than the treatments outlined by Metcalfe. After being washed and transferred successively to 50 and 70 percent alcohol, the sections were stained in a fresh prepared mixture of one part haematoxylin and 15 parts safranin (1 percent in 70 percent alcohol for 30 minutes). After dehydra- tion in 70, 95 and 100 percent alcohol and transfer to xylol the sections were mounted in Permount. Transverse sections of the pinnae of Eriosorus cheilanthoides and of the pinnules of E. myriophyllus were prepared by a similar method. Studies of the epidermis, vascular system of the leaf and seg- ment borders were made from material immersed in 50 percent NaOH from several hours to two days, washed in water, hardened in 50 percent alcohol and then mounted in lactic acid. The dia- grams and drawings showing cellular details of structures have A MONOGRAPH OF ERIOSORUS 7S all been drawn from the prepared sections projected on a Bausch and Lomb microprojector. Sporangia and spores were studied mainly from materials mounted in lactic acid, and special prepara- tions are noted in the discussion of spores. izome. In all species the axis is repent or decumbent. In external morphology, the rhizome is generally cylindrical and elongate, usually with very short, compact internodes. It is slender —less than 10 mm. (usually between 2-4 mm.) in diameter—and sometimes dichotomously branched. The surface is obscured by appressed, bent petioles and adventitious roots which greatly increase the rhizome girth. Anatomical differences in the rhizomes of Eriosorus myriophyllus and E. cheilanthoides are noted in the description of the tissues. The stelar system is an amphiphloic G. 5. Rhizome. Diagrams of the amphiphloic siphonosteles and cellular details of tissues traced with the aid of a microprojector. Aa-Ab Eriosorus myriophyllus : Aa, diagram with one leaf gap, the epidermis with basal cells of the les Ab, oO ryo xylem w (cH). Ba-Bb E. cheilanthoides: Ba, diagra’ epidermis with basal cells of the bristles; Bb, cellular det tracheids, both from Tryon & Tryon 6724a (GH). you m with two leaf gaps, near a third, the ails, the xylem of compact 76 ALICE F, TRYON siphonostele with an elongated leaf gap usually interrupting the cylinder (Fig. 5Aa) or with two or three overlapping gaps. The slender rhizome in E. cheilanthoides has a more complex form with three overlapping gaps (Fig. 5Ba) which approaches a dic- tyostelic system. The epidermis is not strongly differentiated from the cortex. In Eriosorus myriophyllus (Fig. 5Ab) the cells are more irregular- ly aligned and thinner walled than in E. cheilanthoides (Fig. 5Bb). The basal cells of the rhizome trichomes adjacent to the epidermis are usually larger than those of the epidermis itself. In some sections, cells of both the epidermis and cortex adjacent to the trichomes are enlarged and possibly have a secretory function. Both species have trichomes with glands and E. myriophyllus has especially copious exudate. The cells of the cortex, the pith, and connecting tissue in the area of the leaf gap are strongly lignified. In Eriosorus myriophyl- lus the cells of the peripheral 5-8 layers of the cortex are thicker walled than the central 6-10 layers. In E. cheilanthoides, the cortex is composed largely of thick-walled cells comprising 7-10 peripheral layers with 2-4 layers of starch-storing parenchyma cells adjacent to the vascular structure. Thin-walled parenchyma also occurs in the cortex of Jamesonia rhizomes but appears to be unusual in other ferns. The lignified cells are especially prominent in E. cheilanthoides and constitute the largest part of the cylinder (Fig. 5Bb). The endodermis is readily identified by thin walls and the deep-staining Casparian bands which are most conspicu- ous, in transverse section, on the radial walls. The endodermis also envelopes the vascular traces connecting with the roots and petioles. The vascular tissue consists of inner and outer layers of phloem composed of angular, thin-walled sieve and parenchyma cells, surrounding the central xylem core. The most striking difference in rhizome structure between the two species is in the form of the xylem. In Eriosorus myriophyllus thin-walled parenchyma cells form conspicuous strands through the xylem, while in E. cheilan- thoides the xylem is composed wholly of compact lignified tracheids. In both species the tracheid walls have compressed helical thickening. The indument of the rhizome has been employed in several classifications and phyletic schemes treating the “Gymnogram- A MONOGRAPH OF ERIOSORUS 77 moids,” including Eriosorus. Simple rhizome trichomes are one of the basic characteristics unifying the central genera of the “Gym- nogrammoides” and also of the larger group, “Chaetopterids,” of the Polypodiaceae. Structure of the rhizome indument has been studied here in some detail because of its taxonomic importance. In the descriptions of the trichomes, differences in the disposition and color are noted and also the number of basal cells and the shape of the apical cell. Unfortunately, many of the collections are without rhizomes. They are not known in Eriosorus Orbigny- anus and E. accrescens, and in E. Ewanii only rhizomes of juve- nile plants have been seen. The general form of the rhizome indument in Eriosorus ranges from a simple, uniseriate trichome to a broad, flattened true scale. Uniseriate trichomes occur adjacent to the rhizome apex in all species, and this is considered to be a basic form characteristic of the genus. Rhizome indument in 17 species is predominantly of this type, but in several species the indument is essentially trichome-like but with two to four cells at the base. These rather simple bristles represent forms intermediate between trichomes and thickened, broad bristles. In six species, some of the indument is broader at or near the base, up to 10 cells wide, several cells thick, and is deep brown to black in color. These structures are also regarded as bristles but represent scale-like forms. The excep- tional occurrence of true scales in E. flexuosus var. galeanus (Fig. 33Ba) clearly represents a specialized type of indument. The rhizomes of var. galeanus have bristles as well as light brown or tan colored, flattened scales. The rhizome trichomes are often glandular with the apical cell inflated—usually pyriform or capitate. The wall of the apical cell is much thinner than other cells of the trichome and the outer layers appear to be lost as the cell becomes secretory. In the descriptions of the species, trichomes are noted as glandular when exudate is apparent on the apical cell. The occurrence of bristles and scales in Eriosorus correlates with other more specialized morphological characters. Most species with such indument also have elaborated, scandent, or reduced linear leaves and some also have more specialized spore characters. These correlations, as well as the occurrence of simple trichomes in all of the species, reinforce the concept that bristles and scales represent a derived state in the genus. 78 ALICE F. TRYON Roots. Adventitious roots are found on all surfaces of the rhi- zomes. They are usually more abundant adjacent to the petioles than elsewhere, but often densely clothe the entire structure. In Eriosorus myriophyllus they are deep brown, strongly bent, widely spreading and usually about 1 mm. in diameter. In E. cheilan- thoides they form a compacted mat around the rhizome, are light brown, less than 0.5 mm. in diameter, and are densely covered with lustrous, gold-colored root hairs. A collar of epidermal tissue protrudes from the rhizome surface and ensheaths the roots. This structure, illustrated in E. insignis (Fig. 6a) is characteristic of the adventitious roots in both Eriosorus and Jamesonia. The epidermis, in transverse section, consists of thin-walled cells, small- er than those in adjacent cortical tissue. Cortex cells in the outer 4 or 5 layers have slightly thicker walls than the epidermis and contain deep-staining inclusions. An inner layer adjacent to the EPIDERMIS INNER CORTEX a t: a, Portion of rhizome with five petiole bases, adventitious roots with ensheathing collars, and trichomes, enlarged, Eriosorus insignis, Brade 15802 (RB); b, c, transverse sections of root with thickened inner cortical layer in cellular detail, traced using a microprojector; b, E. myriophyllus, Tryon & Tryon 6745 (cH); ¢, EZ. cheilanthoides, Tryon &Tryon 6724a (cu). A MONOGRAPH OF ERIOSORUS 79 endodermis (Fig. 6c, b) has very large cells with differential thickening on the inner tangential and radial walls. The endo- dermis is composed of a relatively few elongate cells with con- spicuous Casparian thickening on the radial walls. The vascular tissue consists of a central xylem core of 4-6 large tracheids with groups of smaller protoxylem elements at opposite ends, in a diarch arrangement. Elongated phloem cells with angular walls are clustered, adjacent to the larger tracheids. The pericycle con- sists of 1-3 layers of larger parenchyma cells, which are between the phloem and endodermis. The peculiar, enlarged cells with thickened walls in the inner cortex of Eriosorus (Fig. 6b, c) are located in a position similar to a layer of enlarged but unthickened cells in the roots of Adiantum, as described by Ogura (1938). In the roots of Anemia colimensis, similar tissue is described by Mickel (1967) as “a sclerified pali- sade layer of inner cortical cells.” The differential deposition confined to the radial and inner tangential walls of this tissue in Eriosorus resembles the endodermal thickening reported by Esau (1953) in roots of certain monocots. Leaves. The leaves are closely placed on the rhizome in most species. They are borne in a spiral sequence but with paired members in nearly opposite positions on the stem. The leaves show greater variation than other organs and in this genus there are major trends toward reduction and elaboration of the lamina. A tendency toward leaf dimorphism is apparent in several species but is most pronounced in Eriosorus hispidulus. Leaf complexity is quite variable. In the descriptions of the lamina, division is given in respect to the “normal” maximum, exclusive of exceptional cases of further division. Representative portions of leaves are shown in Fig. 7 to illustrate the use of the terms lobe and ultimate segment as applied in the descriptions. The term ultimate segment is especially critical in Eriosorus and it is applied to the ultimate division of the lamina having two or more veins. It is used with reference to leaves with segments of tertiary or a higher order (the primary order is equivalent to the pinna and the secondary to the pinnule). Definitions of other terms follow those in the glossary of terminology of the fern leaf by Rolla Tryon (1960). The term pinnatifid is not used here as it cannot be applied consistently in this genus with any precision. 80 ALICE F. TRYON ULTIMATE SEGMENT Fic. 7. Leaf complexity with ee applied in descriptions. a, pinnule, secondary division of 3-pinnate lamina; b, tertiary segment of 6-pinnate lamina; c, two ultimate egments; d, pinna, primary division at 2-pinnate lamina The least complex lamina, in E. longipetiolatus, is about 10 cm. long, once pinnate and with as few as 13 entire pinnae. In the most complex leaves, as those of E. flexuosus, the lamina may exceed four meters in length, is scandent or scrambling, fractiflex and up to six times pinnate with the pinnae oriented in several planes. Leaves of both of these species represent extreme forms. Most species have the lamina 30-50 cm. long and are two or three innate. Epidermal cells of the leaves, in transverse section, are oval or have irregular lobes protruding into the adjacent spongy tissue. The cells of the lower epidermis are slightly smaller and have stomates which do not, or only slightly, protrude from the surface. Cell wall patterns of the leaf epidermis are included in the figures for each species. They were traced, using a microprojector, from segments partially cleared in sodium hydroxide. The tissues were A MONOGRAPH OF ERIOSORUS 81 peeled, mounted in lactic acid and the cell walls were traced from comparable regions between the veins. Cells of the lower surface, adjacent to the veins, are usually longer than those be- tween the veins. Several examples of variant patterns are illus- trated from samples of Eriosorus flexuosus and E. hirtus showing the differences in size, density and orientation of the guard cells. Eriosorus was not included in the survey of stomates in the ferns by Kondo (1962), but the pattern resembles that of Woodwardia orientalis and is of the 2A type in his system. This type is based on the development of the guard cells and their attachment to the cell walls after division of the stomatal initial. Among epidermal cell wall patterns of Eriosorus flexuosus (Fig. 34) the smallest guard cells (Fig. 34Ab) are found in the type collected in the vicinity of Caracas. In contrast, the largest cells (Fig. 34Ah) are found in the hybrid with E. paucifolius from Cerro Auyantepui in southern Venezuela. The patterns in E. flexuosus from Mexico (Fig. 34B) have exceptionally undulate walls in the upper epidermis and the guard cells are only slightly smaller than those of the hybrid. The collection from Cerro Auyantepui is treated as a hybrid on the basis of an intermediate leaf form between that of E. flexuosus and E. paucifolius. The spores are unusually sculptured with exceptionally broad, irregu- lar equatorial flanges. The large epidermal cells in these speci- mens may also indicate a hybrid origin of these plants. Such differences in the epidermal cells and spores when correlated with chromosome numbers may allow a preliminary assessment of polyploidy from herbarium specimens. The leaf rachis usually has a slightly lighter color than the petiole and in Eriosorus myriophyllus and E. flexuosus it is mostly straw colored or tan. The channel on the adaxial surface is con- tinuous with that of the pinnae stalks. The lamina tissue is often decurrent on the rachis, especially in the apical portion of the leaf. A single vascular strand extends throughout the rachis and in transverse section the tissues are similar to those in the petiole apex. The lamina is anadromic in leaves more than once pinnate and the basiscopic pinnules, especially in the basal pinnae, are usual- ly enlarged. These characteristics of the lamina are useful in reconstructing the position and orientation of fragmentary por- . tions of large leaves. 82 ALICE F. TRYON The petiole bases are usually appressed to the rhizomes and are strongly bent or bowed. This orientation of the petioles is similar to that in Jamesonia and some species of Pterozonium. They are more strongly appressed to the rhizome than in other groups, such as Pellaea, which also have slender, elongate rhi- zomes. The petiole length may vary from 1/12 as long as the lamina, as in Eriosorus cheilanthoides, up to four times longer than the lamina as is found in the aptly named E. longipetiolatus. Near the rhizome the shape is terete or subterete and at the apex it is plane or channeled on the adaxial surface. The color is usu- ally brown ranging from castaneous to atropurpureous except in E. myriophyllus and E. flexuosus, in which the apex is usually tan. In transverse section, the epidermal cell walls appear strongly thickened and the lumen is small and irregular. The cortical cell layers nearest the epidermis also have thickened walls but the lumen outlines are fairly regular. The largest portion of the cortex, 7-12 layers outside of the endodermis, is made up of thin-walled parenchyma. The vascular tissues near the rhizome form a broad U-shaped strap, becoming sharper and V-shaped near the apex of the petiole. Protoxylem occurs at the base of the V and at the ends of the arms where it is overarched by a few metaxylem cells. In Eriosorus myriophyllus the xylem has strands of parenchyma similar to those found in the rhizome of this species. The phloem is mainly along the outer sides of the arms and interrupted or with few cells at the ends. Veins. Veins usually terminate at the margin of the ultimate segments. In Eriosorus Lindigii, E. hirsutulus and E. hispidulus the veins terminate short of the margins. This condition is so constant that it is useful in characterizing these species. The vein ends are usually only slightly broadened in most species but in E. rufescens and the closely allied E. setulosus they are much enlarged to broadly clavate or cuneate. The vein ends are quite elaborate in E. Stuebelii and E. aureonitens. They are not only enlarged but, in the latter especially, the veins protrude into the teeth along the segment margins. In E. longipetiolatus the veins are deeply immersed in the coriaceous lamina tissue. In E. Biardii, which has an herbaceous lamina, only the ends are immersed on the abaxial surface. The most extreme elaboration of veins is found in E. Ewanii where the ends are strongly dilated into a pad of thickened tissue. This is particularly remarkable as it shows the development of a completely unique character in the genus. A MONOGRAPH OF ERIOSORUS 83 The trichomes of the lamina, particularly among the sporangia, were compared in Eriosorus, Jamesonia and Pterozonium by A. Tryon (1965) with respect to the definition of paraphyses. Names of some taxa used in that work have been changed and terms have been clarified in this revision, but the following basic idea is re- emphasized. In Eriosorus the indument occurring among the sporangia consists of trichomes; they may be glandular, but are not differentiated from those on other parts of the lamina, and cannot be construed as being paraphyses. Leaf trichomes which are described as crispate may be variously curled or twisted and are disposed in a lax manner. These contrast with rigid ones which are usually shorter and erect or appressed. The elongate apical cell of the trichome is usually somewhat acuminate and tapers to a rather rounded apex. The form of the globose apical cell ranges from slightly enlarged to pyriform or capitate. The trichomes may be clear and quite colorless, tan to deep brown, or bicolorous. More than one form of trichome may occur on the same structure, as is often the case on the rachis and petiole. A few species seem to have essentially glabrous mature leaves, but some type of indument usually occurs in channels on the adaxial surface of the rachis and also at the pinnae axils. In Eriosorus Wurdackii the adaxial leaf surface appears glabrous but there are tufts of deep brown trichomes at the pinnae axils which are similar to trichomes at the axils in Pterozonium. The petioles often appear less strongly indumented than other parts of the leaves, but there are usually many scars from decidu- ous indument on the epidermis. Petiolar indument is complex because near the base it resembles the rhizome indument. It is usually more abundant at the apex and there it resembles indu- ment of the rachis. The greatest development of leaf indument in Eriosorus is in E. aureonitens and E. Stuebelii the Andean species occurring from southern Colombia to southern Peru. The leaves of these species'are completely enveloped in tawny or rust colored tomen- tum similar to that found in several species allied to Jamesonia canescens which grow in northern Colombia and Venezuela. There are no close geographical connections between these groups and there are no other resemblances; thus, it seems there has been a parallel development of the tomentose condition in the two genera. This type of indument contrasts with that in E. rufescens, E. setulosus and E. longipetiolatus in which the trichomes are 84 ALICE F. TRYON discrete, rigid and usually bicolorous, ruddy or deep brown and clear or tan at the base. These rigid trichomes are similar to those in Jamesonia cinnamomea and J. Goudotii which occur on the same paramos in southern Colombia with these Eriosorus species. The similarity of indument and their close geographical associa- tions suggest possible hybridization as noted in the discussions of E. setulosus and E. longipetiolatus. About half of the species of Eriosorus have trichomes bearing copious exudate on the apical cells. There are different forms of the glands. In E. myriophyllus they have a pyriform apex borne on a long, uniseriate stalk and are quite distinct from the glands with a capitate apex on a short stalk, as in E. Ewanii. In the latter species, the leaf surfaces are densely covered with capitate glands also characteristic of Jamesonia cinnamomea, which occurs on the same paramos in southern Colombia with E. Ewanii. The similar- ity of indument and geographic associations of these plants sug- gests the possibility of hybridization involving Jamesonia as noted in the discussion under E. Ewanii. Sporangia. The sorus in Eriosorus usually extends for most of the length of the veins in the ultimate segments and there is no indusium. The sporangia develop in an outward (or acropetal) sequence progressively along the vein toward the margin. The dev equence of the sporangia differs from that in other genera such as Pellaea and Notholaena in which the younger sporangia are produced basally on the veins. In other “Gymno- grammoid” genera with prolonged linear sori, such as Syngramma, Craspedodictyum and Aspleniopsis, the sporangia are in a mixed state of development along the veins and the youngest are not concentrated in the distal portion as they are in Eriosorus. The mature sporangia are often most abundant on the penultimate veins. In E. Wurdackii and E. Orbignyanus they are restricted to the terminal portion of the veins and form submarginal bands. Sporangial structure of Eriosorus congestus (see Fig. 8) shows differences in the two faces, especially the marked asymmetry of the capsule. The form is generally pyriform and somewhat longer than broad, or orbicular. The annulus is interrupted by the stalk and the number of indurated cells ranges from 12-26. The number of annular cells was formerly considered to be, but is not, tax- onomically significant in this group. There are 2-6 thin-walled cells between the annulus and stomium and below these 24 A MONOGRAPH OF ERIOSORUS 85 indurated cells, between which the sporangium opens. There is usually a tier of three cells directly subtending the capsule and from 1-3 tiers between this and the receptacle. The sporangia in Eriosorus differ from those of other groups in the Polypodiaceae which have elongated stalks. The lower cells of the stalk in Erio- sorus may increase by intercalary division and form a cushion of cells which is not readily distinguishable from cells of the recepta- cle. In E, velleus, five capsules may be subtended by a single cushion of cells. In E. rufescens, E. hirsutulus and E. cheilan- thoides there are often trichomes on the stalk or cushion similar to those on other parts of the leaf. The form of the stalk (Fig. 8a) with three cells adjacent to the capsule and one or two unthick- ened tiers adjacent to the receptacle is more frequent in the genus and regarded as the more generalized type of sporangium than that with intercalary divisions as noted above. Spores. Remarkably good descriptions and illustrations of spores were done by Dunzinger (1901). In his treatment of Gymno- gramma, he regarded spores as the most useful character for establishing species groups. The illustrations, although simple line drawings, clearly show the unique sculpture o the spores in lateral view as well as on the main faces. Irregular or aborted Fic. 8. Sporangia and spores. a—c, Sporangia, X 85, Eriosorus congestus: a, proximal face, the stalk with three cells subtending the capsule; b, lateral view showing excentric annulus; c, distal face, Tryon & Tryon 7018 (cu). d-f, spores, E. flexuosus: d, proximal face with equatorial flange at the perimeter with three projecting angles; e, lateral view with two ridges of distal face intersecting in an angle near the equatorial flange; f, distal face with three ridges forming basal triangle and tubercles within the central areola, Tryon & Tryon 7010 (cu). 86 ALICE F, TRYON spores were noted in Gymnogramma elongata. They obviously represent spores of one of the hybrids which are frequent in this complex, treated here under E. cheilanthoides. In the survey of spores by Erdtman (1957) Gymnogramma (Eriosorus) congesta is illustrated, including the surface detail on the two faces. Frag- ments are shown which infer that a layer exists outside of the exine in these spores. Eriosorus flexuosus spores are illustrated by Tschudy and Tschudy (1965) and they indicate that these spores are without perine. My observations confirm this and I consider the fragments of perine shown by Erdtman to be related to the deteriorated wall resulting from acetolysis. Spores of all of the species were examined in dried condition and in lactic acid preparations. Several species were also studied from preparations cleared by acetolysis or by sodium hydroxide. These cleared materials were useful for examination of some of the surface detail but the spores became decolorized and were disintegrated in the process of acetolysis. Deterioration of prep- arations by the same process was also reported by Tschudy and Tschudy and they attribute this to a chemical breakdown of the cell wall. Spores of Eriosorus hirtus and E. congestus were exam- ined with a scanning electron microscope (Fig. 9a-c). The follow- ing general descriptions were drawn from both light and scanning microscope studies. ere are usually 64 spores per sporangium and this is consid- ered to be the normal complement. There is considerable variation a b c G. 9. Photographs of spore details from scanning electron microscope studies: a, Proximal face with central triradiate sear, adjacent tubercles and equatorial flange in perimeter; b, distal face in oblique view with two basal ridges intersecting and three tubercles within central areola, both Eriosorus congestus, Tryon & Tryon 6995, X 500; c, surface detail of ridges and floor of proximal face, E. hirtus, Williams & Alston 294, * 2660. A MONOGRAPH OF ERIOSORUS 87 in size. The spores examined, which were mounted in lactic acid, showed the greatest diameter of the polar face from 40-80u. There seem to be correlations between spore and epidermal cell size which may be of interest in the analyses of hybridization and poly- ploidy in the species. A good indication of hybridization or some other irregularity in specimens is poorly developed or aborted spores, but this is not wholly reliable. There are some specimens which have abundant well-formed spores that seem to be hybrids on the basis of other morphological characters. A study of the spores of such variants, using the scanning microscope, showed irregularities in the structure of the equatorial flanges although the spores appeared well-formed. Spore color in Eriosorus is usually brown, ranging from a mod- erately dark, ruddy shade to deep brown. Among four species with light brown or tan spores, E. hirtus and E. hispidulus are closely related and represent derived forms in other aspects and E. flexuosus and E. cheilanthoides are quite distantly related but represent specialized forms in the genus. Spore shape is basically tetrahedral but flattened on three merid- ional planes which are compressed by contact in the tetrad. The free convex surface is slightly larger than a half sphere and elongated in lateral view. The proximal face (Fig. 8d) is subtri- angular in outline with three convex sides and three angles more or less protruding from the flange or subtending ridge. The tri- radiate scars are slightly raised and extend #~% the distance to the equator. There are broad, parallel ridges or projections, variously coalescent, which form the margo. The ridges, highly magnified in Fig. 9c, consist of coarse, pebbled material. The exine texture of both sculpture and floor appears to be uniform over the entire spore surface. The equatorial ridge is noted in the descriptions as a flange. This may be variable in width and quite thick, and is more or less extended at the three angles which are aligned with the triradiate scar. On the distal face (Fig. $f) three contiguous ridges form a triangular base upon which the spore usually rests. The spores are usually oriented with the proximal or polar face upright. This orientation is possibly advantageous for germination of the spores or early growth of the gametophyte. The central areola within the basal triangle may be quite smooth, papillate or often includes several coarse tubercles. The angles of the basal triangle are connected by short ridges which extend up to and 88 ALICE F, TRYON often protrude slightly at the equatorial flange. In E. myriophyllus and E. Sellowianus the triangle is large. The ridges of the triangle are up on the lateral spore surfaces, nearly parallel to the equa- torial flange, and their ends protrude at the three angles. The spores of Eriosorus are similar to those of Jamesonia and are characteristic of these genera. They are similar to Anemia spores in that the three angles prominently protrude at the equator and that they possess strong, coarse ridges. The variant pattern of parallel ridges noted above in E. myriophyllus also resembles the prominent banding in the equatorial region in spores of Anemia. This also suggests a possible origin of the characteristic basal triangle in Eriosorus spores from more con- tiguous ridges in the equatorial region. SYSTEMATIC TREATMENT Ertosorvs Fée, Genera Filicum 152, t. 13B, f. 1. 1852. Copel. Gen. Fil. 58. 1947. type: Eri ens Fé pel. Psilogramme Kuhn, Fests, 50 Jub. Reals. Berl. (Chaetop.) 332. 1882. TYPE: Gymnogramma elongata Hook. & Grev.=Eriosorus cheilanthoides x Jamesonia. Psilogramme, Section Eupsilogramme Kuhn, op. cit. 335. 1882. Gymnogramma auct., non Desv. Mag. Ges. Naturf, Berlin 5:304. 1811, id est C. Chr. in Verdoorn, Man. Pterid. 304. 1938: Reimers, in Engler, Syllabus Pflanzfam. ed. 12, 1:302. 1954. Rhizome repent, usually with short, compact internodes, an amphiphloic siphonostele with dictyostelic stages, densely clothed with golden brown to black, rigid or crispate, erect’ or appressed trichomes or bristles, with 1-10 cells at the base, rarely scales. Leaves usua y erect, sometimes scrambling or scandent. Lamina elongate-triangular, -rhomboid or linear and 30-50 cm ong, not exceeding 20 cm. and usually less than 10 cm. wide, 1-pinnate to usually 2-3-pinnate, or scandent and up to 4 m. lon m. wide and 6- pinnate. Petiole terete or subterete, near the apex usually plane or channeled astan sometimes restricted to a portion of the vein and aligned in a inal ais developing in acropetal sequence, the capsule usually pyriform or ers A MONOGRAPH OF ERIOSORUS 89 subtending the capsule, often with intercalary cell divisions Sompoage: a cushion of cells adjacent to the receptacle, sometimes with tric s on the stalk. Spores tetrahedral, deep to ruddy brown or lighter, srr tan, the proximal face with —— ridges or tubercules adjacent to the triradiate scar, with a moderate to broad ph ari flange, the three angles confluent otru KEY TO THE SPECIES OF ERIOSORUS . Leaves scandent, ae or ae ne xe : 3 meters long (specimens “ial ane lete), 4 or more b. Ultim — s dichotomously ibe . pencinc bifid, slender, usually with “* or 2 v c. Vein ends not atlas to somewhat —— lamina glabrous or sparsely pubescent, rarely with glandular trichom d. Rachis gang a or deep brown throughout; pinnule rachises aie descen ve * m the pinna rachis in an arc or angle ge ater degrees; lamina pe ac spores deep brown .... 25. E. glaberrimus. d. Rachis cand or deep brown below, the upper portion, especially near the apex, tan or straw colored pinnule ——s fractiflex, usually ascending at an angle with pinna rachis of less than 90 degrees; lam- ina more or less pubescent; eck glandular; aha - or light brown c. Vein ends enlarged, usually dilated at the end, forming a aa of thick- ened tissue at the margin; lamina hispid, with rigid, glandular —— b. Ultimate =o elaine or cuneate (not Thanos abe), foal with 6 to 20 or mo 20. E. Orbignyanus. a. Leaves hei or rif 5 i Ht or vee 1 to 3 times pin nate: lamina of m os leaves mostly between 5-50 cm. long, usually not exceeding 70 ; g. g. Veins extending to or nearly to the margin; apex of the terminal “ entire or nearly so, with borders of elongate cells, ae hg spores deep brown g. Veins terminating short of the margin; apex the terminal lobes eg ular, with the border cells irregularly iden spores light or brown. h. own. h. Ultimate segments pu ubescent, the trichomes without aan gird glandular in intermediates); segment borders wi : more or less projecting at the apex... ..... E irsutulus. h. Ultimate segments hispid, with rigid, glandular trichomes; segment borders papillate with cells irregularly projecting at ‘i. apex ....- : f. Lamina with rigid, bicolorous trichomes or ; pin ceo et i. Pinnae, at least in the lower portion of the lamina, clongte-oate, te en lobed; the margin plane, entire or deeply lobed . . E. setulosus. e a: im F 90 ALICE F. TRYON i. acti gpenten: about as long as broad; the margins incurved or nrolled, WA SE ri a heentin, bo atucetts longipetiolatus. é. in ching eopalae -ovate, or eta. the central or lower pinnae about twice as long as the upper on j. Leaves with tan or rust colored tomentum eek obscuring the lamina surface or if sparsely pubescent, the pinnae stalks at least 1 cm. long; leaves scandent, scrambling, or if erect the pinnae sessile. k. k. Basal pinnae with stalks 1-25 cm. long; rachis fractiflex; leaves with indefinite growt ]. Vein ends ace at the margin, often in a sinus Fae ee aes a wtea Ce a ot Mara hat ye ONY coal gig te worse . accrescens. 1. Vein ends terminating in a tooth protruding from the segment mar. Dis he os Gai atairayet oasis btu ie ones = Sige + ee 6. E, aureonitens. k. Basal — em or with stalks less than 1 cm. gore vere straight or nearly so; leaves with determinate growth ....... . Stuebelii. j. Leaf me deat. apparent, the ase glabrous, sia or gland- ular; leaves usually erect. m. m. Leaves distant on the rhizome, the internodes elongate. n. n. Lamina texture herbaceous to ee the vein ends no scarcely enlarged, rarely subclavate .......... . pau cifollas. ; — texture rigid, coriaceous; vein ends enlarged to broadly clavate o. Pinnules with a broad, strongly decurrent base; pinnae elongate- triangular (the length exceeding twice the breadth); se buds (cro- Bessie: often ne with dense, tan tomentum 9. ranatensis. Pinnules narrowed at the hans: often stalk-like; pinnae ig HC 2 uae a4 ie shea twice the breadth; leaf buds small, glabrous PS ee ye sex ioe eed ae ees ct, MRE re cresanicsl. m. Rides with ee _ be Bed internodes short, Pripmaate p- p. Veins terminating at or near the in in a lobe o} > Rachis and upper ol - the welia as tan or straw poled ¥. Ultimate segments usually plane, with obtuse, mostly emarginate Wpinee is Re ce lam een ctiaeaie bees can: 1, E. myriophyllus. r. Ultimate segments incurved or enrolled, often bead-like with iate, usually acute apices .............. 2. E. Sellowianus s. Pinnae elon ngat oto or -triang ar, what longer than the apical sig the ees se a _ the pinnae usually larger. t. t. Rachis flexuose; pinnae descending or at right eae _ the = 21. PU OS Lee ee IE pe oer ee ma E. insi t Rachis usually ara pinnae more or less ascending or at Heh angles to the rac is. Lamina 3- or 4-p mane the pinnules elongate-ovate or vere” lar; ultimate bie usually with strong bifid lobes. v. Rhizome trichomes light or golden brown, 2 or sc 1 cell at the base, often => spores deep brown 3. E. congestus. v. Rhizome bristles deep brown or black, thickened, with meet (3-8) cells at the base, rigid, erect; spores tan or light bro amina 2-pinnate, the pinnules ovate or cuneate "with ‘be. ss a lobes, the margins crenate, retuse or more deeply cleft E. rufescens. s. Pinnae lanceolate, the basal pinnules not or slightly eg than the apical ones; pinnae equilateral A MONOGRAPH OF ERIOSORUS 91 ae Veins terminating in a lobe short of the margin e margins with a prominent, yellowish rim; upper surface of the lamina pubescent or glandular with ee erect trichomes . hispidulus, Xx. Pkioate. segments orbicular with few, coarse es series yh ak ane 1. Eriosorus myriophyllus (Sw.) Copel. Gen. Fil. 58. 1947 Fic. 10, Mar 2 Gymnogramma myriophylla Sw. Vet. Akad. Handl, 58. 1817. Freyreis, Brazil, Villa Rica (now Ouro Preto). August 1815. s-pal, vere GH; isotypes: s-Pal photo cu; BM-fra sirens raat Fée, Gen. Fil. 158. 1852. (non Swartz, 1817, Paesia). TY ussen, Brasilia, ex char. “indusio obsoleto, sporis trigonis.” Cheilanthes elandul ifera Moore, Ind. Fil. 242. 1861 (non roe Peo based on wi s glandulosa Fée. Moore’s name was taken us Fo Crypt. Vas Ores. st :55. 1869, but not as a new name as accepte by some ae Anogramma villosa Fée, Crypt. Vasc. Brés. 1:60, 1869. TYPE: Claussen, in 1841, Brazil, Minas Geraes P! photo GH; nomen nud. Gen. Fil. 184. 1852. Psilog Ta ae meee (Sw.) Kuhn, Fests. 50 Jub. Reals. Berl. (ques ). 33 oe bate ne myrio jophylla Sw. var. eglandulosa Rosenst. Hedwigia 46:148. 1906. a Schmalz 132, Brazil, Santa Catarina, Tresbarrassera, erb. Rosenst. s-pa! isotype: Ny! The pepe at s-pa is probably the holo- type but does not bear the varietal na Gymnogramma myriophylla Sw. var. " eglandulosa sap ios Rosenst. Hedwigia 46:148. 1906. TYPE: Hirgens dr bapa , Brazil, R oe rande do Sul, mnogramma Glaziovii C. Chr. je Bot. tl “9( 11) :20. 1910, Based on C. dlendutos Fée (non Swartz, 1817). Gymnogramma Felipponei Hert _ Darwiniana 1:159, t. 160. 19 924: An. Mus. Nac. Montevideo 1:356, t. 35, fig. a—g. 1925. TYPE ses n. 36 et 452 Jan. 1877, Uruguay, Sierra Souza, Cerro Largo, M Rhizome repent (often compact and quite erect at the apex), with short internodes, ca. 3-5 mm. in diameter, with trichomes or bristles — e bud minute. Rachis straight, rarely somewhat fractiflex, the upper channeled, the lamina dec ee near the apex, sometimes slightly at peal 92, ALICE F. TRYON pinnae, castaneous to straw colored, densely pubescent, the trichomes clear or _ erste se — al cell alae usually glandular. Pinnae at right angles o the rachi mewhat ascending, elongate-triangular, rarely ovate, the Satine aide slightly tec 0.25-10.0 cm. long, ve cm. wide, delicate her oro or somewhat membraneous; upper ace ely to sometimes with decurrent lamina ya pinnules elongate-ovate or -triangu- lar; ultimate segments ovate with several — oe ay often bifid, the apex retuse or more deeply cleft, peas eins terminating in a cleft at the margin, not or — enlarged; border 7 narrow, clear, 1 cell wide, the cells , a tended by a tier or cushion of usually brown cells, the eae: af 12-21 indurated cells. Spores deep brown, the proximal face quite smooth, with ridges appressed to the triradiate scar, with a m ~rortancene broad equatorial flange, the angles often be obe See gies face wit large, usually smooth, central areola, sometimes ee ridges nearly parallel to and with the ends ane tate the plesk he flange. Field studies in Brazil indicate that the species has a broad ecological tolerance as the plants occur in humid to xeric situa- tions and at altitudes ranging from 600-2300 m. The compact form and growth of the rhizome are unusual because it is often deeply embedded in heavy, laterite soils. The plants apparently are adapted for survival under dry conditions and possibly light burning which is frequent in some areas where they grow. They are abundant on recently exposed soils along road banks and trails. At the highest point along the trail above the city of Ouro Preto, there were specimens of all sizes including some young ones with deteriorated gametophytes still adherent. Meiotic chromosomes have been examined in material collected near Palmares, Tryon ¢> Tryon 6745 (cH), and although a precise number cannot be reported it is probably between 63-87 biva- lents, and is tentatively given as 87. This population and others from Brazil should be checked because lower chromosome levels may be expected in the species. Eriosorus myriophyllus contrasts particularly with species of the Andean region and five others of Brazil in being exceptionally uniform morphologically. Only a few collections from Rio Grande do Sul and Parana are distinctive in having a more delicate leaf texture and eglandular trichomes. They may represent different cytotypes but they are small speci- mens from rocky sites and are more likely to be depauperate orms. A MONOGRAPH OF ERIOSORUS 93 Fic. 10, Eriosorus myriophyllus: a, habit with few pinnae in detail and rachises of others, X 1/3; b, pi 4 2 both Tryon & Tryon 6877 (GH); ¢, margin with vein end and glandular trichomes, X 34; upper epidermis with trichomes; e, lower epidermis with portion of veins; f, lamina trichomes, upper surface; g, lower surface, all 40; h, rhizome trichomes, X 20, all from Tryon & Tryon 6718 (cH). This species is most closely related to Eriosorus Sellowianus, a more specialized type from the drier areas in Minas Gerais. In e erect orientation of the rhizome apex, it is similar to E. congestus and there are other similarities between them in the details of the pinnae. These two species have the most generalized leaf form which is regarded as the least modified and is the basic form in the genus. The spores of E. myriophyllus and E. Sellowi- anus also have sculpture aligned more like the banded spores of Anemia. 94 ALICE F, TRYON In shade beside streamlets, on damp shaded sandstone, in open or shrubby growth on roadbanks. Brazil and Uruguay, at 600- 2300 m. ADDITIONAL SPECIMENS EXAMINED: Brazil. Minas Gerais: Badini 123 (RB), Itacolomy, 2824 (s, us); Serra do Caparaé, Brade 1 (ny), Serra do Cipo, 97 (c, BHMG, RB); Claussen 102 (c, P), 278 ); Ouro Preto, Glaziou 15738 (x, c, K, P); Belo Horizonte, Markgraf et al. 3554 (8, RB); Dia ina, Mexia 5845 , GH, us); Caldas, Mose (P, 8, S-PA); Villa Rica, Pohl 9 (w); Se e Capanema, Schwacke 9258 (Pp), Ouro Preto, 145! eh ‘esis 2 () Silveira & Thomar, April 1896 (s-PA); ripui, 4 km o Preto, Tryon & Tryon 6848 (cH), Serra do Ouro Preto, pote laa ease 6881, 6882 (cH); Weddell 1569 (P). Rio de a Itatiaia, Brade 6503 (Ny, us), 10050 (R, RB), 10165 (BM, R, BB), 4495 (rp), 15537 (BM, Ny, RB); Ca — Porto 2252 (rp); near Rio, Burchell elie. (GH, K, s-PpA); Organ Mts., Gardner 102 (3M, E, G, P. ; (a, a Serra de Cubatio. Lindberg 22 (B); anal da Bocaina, ion Tr ae S, S-PA, ‘ Herb, Capan ema Ap 1877 (8M, RB); Villa Nova, Annies 7 (ny); Serra S. Luiz, capi 89 (RB); Fortaleza, Prat 2900 (P), Ypiranga, 3375 (BM, P, R, S), sy (s), Riv. Tibagy, 3488 (s), Villa Velha, 4028 (cu, P, B); 14908 ay. Iraty, 7811 (BM, s, s-PpA, us), Serra do Mar, 14434 (3, BM, F, a Serra de S. Luiz de Puruna, Pabst 5915 (cu, HB); Carambehy, Schwa oe 765 (p). Santa Catarina: Lages, Spannagel 106 (s-pa); Bom Retiro, : Grav R Rio Pardo, Faz. Agra, Jurgens, 1906 (8, BM, K, s, s-PA, us); Morro Sapu Leite 1702 (a); Sao Le sige Rick (c Hu). Uruguay. Herb. Arec em. 1875 (s-pa). Cerro Largo: Arechavaleta 455, 2015 (Pp). 2. Eriosorus Sellowianus (Kuhn) Copel. Gen. Fil. 59. 1947 Fic. 11, Map 3 Gymnogramma Sellowiana Mett. ex Kuhn, Linnaea 36:69. aor TYPE: Sello 1365, Brazilia, Herb. Mett. 8! photo cu; isotype s! photo Psilogramme apie (Mett. ex Kuhn) Kuhn Fests. 50 Teh: Reals. Berl. prance ) 337. nogramma S Schwackeana Christ, Pl. Nov. Mineiras 2:18, 1900. LECTO- TYPE: Packs 9398, Brazil, Ouro Preto, Pl; isolectotype: cu-frag.; Para- types: Schwacke 7564; Serra do Ouro ¥iet o, He rb. Christ p!, Em!; Serra de photo cu Eriosorus Schwackianus (Christ) Copel. Gen. Fil. 59, 1947. A MONOGRAPH OF ERIOSORUS 95 Rhizome repent, with short internodes, ca. 3-5 mm. in diameter, with trichomes or bristles crispate, sometimes rigid, light or golden brown, at i u . long. P nne straw colored, from 1/8 to 1/3 as long as the lamina, with sparse to dense the a channeled, the lamina slightly decurrent at the pinnae axils, castaneous to straw colored, densely pubescent, the trichomes clear or light brown, the apical cell globose, eotulae Pinnae slightly to strongly ascending, elongate- triangular to -ovate, sometimes linear, equilateral, 0.3-3.0 cm. long, 0.3-1. m. e, membranaceous or coriaceous, rarely more delicate, subsessile; er surface sparsely pubescent to nearly glabrous, the trichomes clear, the cells wide, the cells sometimes prolonged into glandular trichomes, e at se ta irregular, often protruding from a porangia along th ns often short of the ultimate division, most abundant on the angles often projecting in two shal - usually smoot Sentyal areola, the three ridges nearly parallel to and with ends projecting into the equatorial flange. Constant features characterizing these plants of Minas Gerais include pinnules with dense glands and laciniate margins. The coriaceous leaf texture and bead-like enrolled pinnules are usual but less constant aspects which seem to reflect the xeric habitats in which the plants usually occur. The relationship of this a to E. myriophyllus is relatively close. There seems to be no ovie dence of the kind of variation that is associated with hybridiza- tion. The specialized form of pinnules noted above shows a derived state as compared to E. myriophyllus. Eriosorus Sellowi- anus is the only clearly differentiated taxon that occurs within the geographic area of E. myriophyllus, which ranges from Minas Gerais in Brazil south to Uruguay. These two species provide a standard of differentiation for comparison of variation in the hybrid complexes among the Andean species. Among rocks on planalto, in exposed places or sometimes over- grown by shrubs. Minas Gerais, Brazil, at 1450-1550 m. 96 ALICE F. TRYON A d e . Eriosorus Sellowianus: a, habit, & 1/3, gree 15737 (x); b, pinna, X 6, pone 1779 (GH); ¢, margin — vein end, X 2 : wrt epidermis; e, lower epidermis; f, g, lamina trichomes, f up surface, g i surface along vein, all X 40, from Glaziou 7312 (P); h, we llbias per tetie with ae ferns of rhizome at base, X 20, Glaziou 15737 (x). . a ADDITIONAL peer EXAMINED: Brazil. — Gerais: Serro do Cipo, Brade 14398 (BHMG, BM, nB); Itacolomy, Damazio (Ny-part 1248 (p, R, RB), 1260 60 (R), i784 (2), isda i gated Foster 710 (cu, =H — do Pieda e, Glaziou 7312 (x, Pp), 1 , C, G, K, Ny-frag.), ag. 0. , BM, C, K, P); near Rio Preto, Mendes Magis 3 56 (a ), Alto do Pico ao cad, 1779 (B ae cu), 1810 ( pumc, HB); Cachoeira do Campo, Schwacke, April 1906, (Bm), Se Conersate: 9258 (p), Serra do Piedade, 9777 (P, xB), Ouro Preto, 10701 (P, RB), 12745 (BM, NY, P, RB), 127450 i RnB), Serra do Cachoeira, 14417 (P, RB); ey das Vainio 33257, 33262 (cH, run); Serra do Piedade, Warming, 1866 (BM 3. Eriosorus congestus (Christ) Copel. Ind. Fil. 58. 1947 Fic. 12, Map 4 Gymnogramma congesta Christ, Bull. Herb. Boiss. Il, 4:1098. 1904. TYPE: [Chares by Maxon) Tonduz 12575, Costa Rica, La hag 1459 m., een 1898, P!; isotypes: c! usl; lps mae Wercklé, Costa Rica, p, photo ¢ roraminet: congesta (Christ) Maxon, Bull. Torrey Club 42:81. "915. oS. (often compact and strongly erect at apex), with short : mm iameter, pi crispate, golden pee trichomes or bristles, at the ibe usually with one or sometimes two cells, the apical ye elongate. Leaves erect, 7-105 cm. ag Petiole ane or channeled on upper surface, Sonate to ph! gong ie cual 1/3 to 1/4 longer than the or sometimes equal to it, wi o dense pubescence, the A MONOGRAPH OF ERIOSORUS 97 usually longest, 3-pinnate, 4-50 cm. long, 2-10 cm. wide, determinate, the apical bud minute. Rachis straight, the upper surface channeled, the lamina decurrent at least near the apex, castaneous, densely pubescent, the tri- chomes clear or tan, the apical cell usually elongate, sometimes globose. Pinnae slightly ascending, the basal ones often strongly ascending, — triangular or -ovate, the basiscopic side usually larger, 0.5-9.0 cm. : 0.34. er surface moderate to densely s a moderate. broad equatorial flange, the angles not or slightly a ig the distal face This is the most abundant of the Costa Rican species, growing largely at lower altitudes beyond the range of the others. It is common along road banks, on mossy turf, often in shaded sites but appears to be tolerant of open sun and drier, clay soils. In the Cordillera Central and the Talamanca Range it grows in cut- over woodlands in the cloud forest, and thrives ih deforested areas, apparently invading the open places. Evidently the species reproduces freely from spores because there are abundant young plants in these areas. At La Palma it is frequent, especially at the bases of tree stumps. Scandent plants of Eriosorus glaberrimus also occur here on the few remaining trees. A specimen intermedi- ate between E. congestus and the former [Tryon & Tryon 7612 (cH)], more closely resembles E. glaberrimus in its scandent habit and is treated as a hybrid under that species. Cytological samples of five populations of Eriosorus congestus from the provinces of Heredia, Alajuela and Cartago uniformly have 87 bivalents at meiosis. This is regarded as a hexaploid level originating from a triploid and achieving a balanced cytological condition by the doubling of the chromosomes. The lower poly- ploid levels have not appeared in the populations sampled in Costa Rica. 98 ALICE F. TRYON Mars 2-5. Map 2, Eriosorus myriophyllus. Map 3, E. Sellowianus, both Brazil. Map » E. congestus. Mar 5, E. paucifolius, p, var. paucifolius, s, var. Steyermarkii, n, var neblinae; hybrid with E. fleruosus var. flexuosus, star. Eriosorus congestus represents the least specialized form among the Costa Rican species on the basis of the elongate-triangular, 3-pinnate leaves with undifferentiated margins and the simple rhizome trichomes. These characters, as well as the nearly sessile, and often decurrent pinnae and dark brown spores, suggest that it is most closely related to the Brazilian E. myriophyllus. ong mosses in open, cut-over woodlands in the cloud forest, in thickets or-on road banks in mossy vegetation or soil. Costa Rica, at 1300-2340 m. ADDITIONAL sP EXAMINED: Costa Rica. 1901-1905, Wercklé (Micu, s-pa), 1903 (cH), 207 (e). Heredia: Vara Blanca, between Pods and Barba volcanos, Maxon ¢> Harvey 8380 (s-pa); Scamman 7048 (cu); slope Bar H); , Godfrey 3518 (cH, K, s-pa); vicinity of Vara Blanca, Tryon & Tryon 6995, 6997 A MONOGRAPH OF ERIOSORUS 99 (cH), s.e. slopes of Barba, 7018 ia Alajuela: Pods, Hunnewell 16508 (cx); Alfonso Jiménez 821 (¥F); Palmira, Austin Smith F79, H288, NY1410 (¥F); Scamman 7625 (cH). San Teel. ie Palma, A. & rade 85 (3, BM, P, 5S, a ey al. 17904 (¥F a Tryon & Tryon 7044, 7056, 7059 (cH); near La Sierra, L. O. Williams 16357 16464 (Fr), Williams et a 28108 (¥, GH). bit with some pinnae in de tail and rachise iru from Tryon & Tryon 7018 (GH H); ¢, margin 1 e, lower epidermis; f, g, sane trichomes, f low urface, all X 40, from Tryon & Visi 6995 (GH); h, iciae ee ab, Tryon ’ Tryon 7003 (GH). 100 ALICE F. TRYON 4, Eriosorus paucifolius (A. C. Smith) Vareschi, Fl. Venez. 1(2):641. 1969 hizome repent elongate, with long internodes, 1.5-3.0 mm. in diameter, the trichomes or bristles ioe appres sed, ray brown, at a base one or two cells, the apical cell globose. Leaves er sere ca . 14-92 long. Petiole ebtorets or plane on the upper surface ropurpur or we brown, Biel to about 1/3 as long as the lamina, coal densely plant rt, clear or tan glands, the apical cell globose, also with some ihgae darker trichomes. Lamina elongate-trullate, -ovate or ovate-lanceolate, the longest pinnae in the lower half of the lamina, the basal ones usually the apex ac large cm. long, 0.3-3.0 cm. wide, herbaceous or itso ane upfoce usually slightly fas Ra the trichomes mostly short, erect, clear or tan, with the apical cell globose, glandular, or few longer, eglandu- own ridges adjacent to the triradiate scar, the equatorial flan ange narrow or mod- erately broad, sometimes slightly irregular, the three angles not projecting, the distal face smooth within the central areola or with a few large tubercles. These collections from isolated Guayana massifs—Duida, Roraima, Ptari-tepui and Neblina—are included under one species on the basis of similarities in several characters. They are alike in having slender rhizomes with long internodes and ruddy brown, uniseriate trichomes, the leaves with short, glandular trichomes on the lamina, and deep brown, sparsely sculptured spores. Differences in the division of the leaves and the shape of the ultimate segments in these are less relevant than the similarities noted above. Collections from the state of Bolivar, proposed as hybrids with this species under Eriosorus flexuosus var. flexuosus possibly involve var. Steyermarkii, which also occurs in Bolivar. The strongly fractiflex rachises in the Ule collection included under that variety also suggest a possible connection with E. flexuosus. A MONOGRAPH OF ERIOSORUS 101 NE NE J 1 Garey ~) ayy WY, g vA Wr, Wr af ene t = surface; i, j, Mathews 1814 (Bm); k, 1, Lechler 2255 (GH); m, rhizome bristle, 20, Steyermark 57346 (us). ized. The latter are restricted to paramos at higher altitudes, mainly in southern Colombia. The connections of E. rufescens with species at less specialized levels are not clear because there seems to be no convincing evidence to draw upon. A few collec- tions from northern Peru [La Pucarilla, Cajamarca, Lopez & Sagdstegui 5456, 6713, 6714 (cH)] have leaves which are less reduced and possibly relate to more generalized species. They seem best placed under E. rufescens on the basis of several details of the borders, veins and indument. On deep mossy banks in ceja montafia, in shaded crevices of bluffs and on earth banks, at 2440-3600 m. Venezuela to Bolivia. ADDITIONAL SPECIMENS EXAMINED: Venezuela. Tachira: Paramo de bn Steyermark 57346 (us). Colombia. Cauca: between Leja and ner es, Lehmann 4427 (, x, P, us). Ecuador. Pearce 250 (x). Canar: Cerro Yangu- 126 ALICE F. TRYON ang, e. of Azogues, F osberg & ues 22782 (us). Peru. La Libertad: Puerta del Monte, Pumatambo, Lépez & Sagdstegui 3436 (cu). Hudnuco: Carpish.., ms : t Yungas, Unduavi, Buchtien, Feb. 1914 (c, Pp), 6 24, ‘1908, 2165 ls Nov. 1910, 2648 (s-pa, us); Pearce, Dec. 1865 K). VARIANT INVOLVING ERIOSORUS RUFESCENS e spores of the following collection are highly irregular and the rachises are oa pee flexuose which suggests that it is an intermediate possibly with E. flexu rh Li co aun of that species was made by Killip & Hazen from ry fore a ewhat lower altitude, in the same locality. Colombia. lima: “Guindio Trail, Killip & Hazen 9494 (cu, ny, S, US). 11. Eriosorus setulosus (Hieron.) A. F. Tryon, comb. nov. Fic. 21, Mar 11 Gymnogramma setulosa Hieron. ae Bot. Jahrb. 34:479, 1904. Typx: Lehmann 6180, ee in monte Paramo de Achupallas, inter Almaguer et 200 m a Cruz, 3000-32 B! photo cH; isotypes: x! te cH; P! photo cH; vs! Rhizome repent, the internodes short, ca. 3 mm. in diameter, with r igid, appressed trichomes or bri stles, lustrous, deep brown or the base 1 or 2 cells, the apical cell gras or globose, glandular. Leaves erect, 13-42 cm. long. Petiole slender, terete near the r izome, channeled near the ina castane- wn, a ith similar, denser trichomes; stalk 1-3 mm. on basal pinnae, often tan or green with decurrent lamina tissue; ace usually slightly raised from upper surface, terminating short of the mar usually br — clavate; der no nti a onl salle: with many tri- chomes similar to those on the lamina su ace. Sporangia most abundant on penultimate segments extending alon ng main veins to the costa, the stalk of 2 tiers of unthickened cells, annulus of 16-21 cells. Spores tan or golden rown, the proximal face with tubercles and short ridges a eae to the triradiate scar, with a ieee often irregular equatorial saa angles Preeeings the distal face with many prominent tubercles within ch central A MONOGRAPH OF ERIOSORUS 127 sy /] a Xe) (4 ey, Le) 53 Bee fil ion Fic. 21. Eriosorus setulosus: a, lamina with apical of Pp 1/3, Lehmann 6180 (us); b, rhizome from small plant with four petiole bases, the apex at left, & 1/3, Tryon & Tryon 5958 (GH); c, margin with basal cells of trichomes 20; d, e, epidermis with basal cells of trichomes darker, X 40, d upper surfac lower surface; f, trichome from lower surface of lamina, all X g, upper epidermis, h, lower epidermis, X 40; i, rhizome trichomes, X 10, all from Tryon & Tryon 5958 (GH). Eriosorus setulosus is a true paramo species occurring at the higher altitudes for the genus. It closely resembles E. rufescens, with which it occurs in southern Colombia. The larger guard cells shown in Fig. 21 e, h, suggest that it represents a high polyploid level. It occurs on the same paramo with E. longipetiolatus and with Jamesonia Goudotii in southern Colombia and has recently been collected with specimens of Jamesonia Scammanae by Sparre in northern Ecuador. Two other species, Jamesonia verticalis and J. cinnamomea, also occur on paramos in Cauca and represent a species group in that genus which is more closely allied to E. setulosus than to others in Jamesonia. The more reduced lamina cell size and spore irregularities in E. setulosus suggest that it may have a hybrid origin involving one of these species of Jamesonia and E. rufescens. On paramos, in mossy banks, at 3000-3750 m., southern Colom- bia and Ecuador. ADDITIONAL SPECIMENS EXAMINED: Colombia. Cauca: Paramo de las Papas, ca. laguna La Magdalena, Idrobo et al. 3089 (coL, GH); Paramo de Puracé, 25 km. e. of Popayan, Tryon & T: 8 (cH). Ecuador. Carchi: near Voladero, Barclay & Juajibioy 9387 (cH); Paramo El Angel laguna oriente del Voladero, Sparre 14199 (cH, s). 128 ALICE F. TRYON 12. Eriosorus longipetiolatus (Hieron.) A. F. Tryon, comb. nov. Fic. 22, Map 11 Gymnogramma longipetiolata Hieron. Engl. Bot. Jahrb. 34:479. 1904. TYPE: Lehmann 650, Colombia, Narifio, paramos near Bordoncillo, 3300 m. B! photo cH; isotype: LE! photo cH. 2 erect, ] cm. lo slender, terete near the rhizome, subterete or shallowly channeled near the lamina, castaneous, shining, usually 3 or 4 times longer than the lamina, with i brown, the apical cell m. deep brown with a clear base; stalk 0.5-2.0 mm. long, often tan or green with ridges continuous wi ose of the rachis; veins depressed in the upper surface, usually strongly clavate, short of the margin; border with a row of thick-walled cells about as long as broad, or irregularly dentate, with tri- chomes similar to the lamina surface. Sporangia most abundant on the penultimate veins extending along the main veins toward the rachis, the The orbicular pinnae with strongly depressed veins are unique features of this paramo species. It appears most closely allied to, and has been collected with, Eriosorus setulosus on Péramo de las Papas in southern Colombia. Jamesonia Goudotii which also oc- curs there has pinnae disposed in two ranks and with strongly incurved margins. In the treatment of Jamesonia (1962) some collections from this paramo were included as variants of that species. Two other species, Jamesonia verticalis and J. cinnamomea also occur on the paramos of Cauca. The latter is especially sim- ilar to E. longipetiolatus in having orbicular pinnae. On paramos in rock or wet places, at 3300 and 3530 m. ADDITIONAL SPECIMENS EXAMINED: Colombia. Cauca: Pdramo de las Papas, around Laguna La Magdalena, Idrobo et al. 3169 (cox, cH). A MONOGRAPH OF ERIOSORUS 129 e . Eriosorus pigakptk ae he habit t, X 1/3; b, pinna, lower ie with 3- odciey x Pas. oe with trichome, 20; d, upper epiderm e, lower pe toon rmis; f, g, lamin nee ri chon oe f upper surface, g lower surface; h, saiske trichome, LX 403.1, ehiccuis trichomes, X< 10, all from pit et al. 3169 (coL). 13. Eriosorus cheilanthoides (Sw.) A. F. Tryon, Brit. Fern Gaz. 9:271. 1966 Fic. 23, 24, Map 13 Grammitis cheilanthoides Sw. Syn. Fil. 23, 219, 419. 1806. type: Tristan da Cunha (Mauritius in error). Herb. tag ig photo cH. Asplenium filipendulaefolium sib Fl. stipe 34, t. 4, Oct. 1808. rypE: du Petit-Thouars, Tris the can p! photo eon ae flipendulosfolia ( ‘(Pet -Th.) Desv. Gok. Nab, Berlin ag 5. asia cheilanthoides (Sw.) Kaulf. Enum. Fil. 71. 1 Psilogramme cheilanthoides (Sw.) Kuhn, Fests. 50 jab. ity Berl. Sueee ) 335, 1882. ymnogramma elongata var. brasiliensis Brade, Arg. Jard. Bot. Rio de Janeiro 13:64, t. 2, £. 3. 1954. Type: Brade 1 15535, Brazil, Pedra shay rosy perto da lagoa, see do Itatiaia, Rio de Janeiro, RB. mm. in diameter, the tri- cm. long. Petiole nati at the rhizome, at the apex p ig Ss —— on the mai seecinase from 1/12 to nearly equal the length of ina, with P ce, the trichomes crispate, clear or tan, pical cell elongate Lamas ear, the central pinnae slightly longer (up to four times longer than broad, in hybrid) b oO i ered, 2- pinnate (1-pinnate in hybrids), 5.5-82.0 cm. long, 0 cm. wide, inde- terminate, usually small, rarely larger than a elon Pp nt. Rachis s ght, pl or somewhat c led on r surface, atro- urpureous to castaneous, moderately to densely pubescent, the trichomes 130 ALICE F. TRYON clear or tan, the apical cell usually elongate, ee globose. Pinnae at right angles to the rachis, or somewhat ascending, elongate-ovate, Pina. 0.5-1.2 cm. long, cm. wide, herbaceous, subsessile; sparsely pubescen t with cri rispate, clear or tan tri ichomes, the pitas cell ie elongate, sometimes globose; lower ebaia with similar, usually -_ ust annulus of 16-20 indurated cells. Spores usually deep brown daaeninte slightl lighter, br i j car, The high chromosome number and considerable morphological variation in Eriosorus cheilanthoides show that this species is more complex than can be shown in a formal taxonomic treatment. The available data suggest that hybridization may account for some of the diverse forms. Three hybrids are proposed after the main citations: the first two are readily distinguished by linear, 1- pinnate leaves and involve species of Jamesonia; the third has 2-pinnate leaves with long central pinnae, two to four times longer than broad, and appears to involve E. flexuosus. Some of the proposed hybrids occur in Ecuador, north of the range of the species; further data are needed to clarify their status. The specimens from the South Atlantic islands of Tristan da Cunha have been critical in the interpretation of variation. The material that I have examined, from the first collection of Petit- Thouars in 1793 to the recent ones of Wace in 1956, provides samples of populations long isolated from related species. These show a considerable range of variation in size and leaf form. They were utilized for comparison with similar specimens of South America which often occur with other related species and with Jamesonia. There is a strong resemblance between specimens from Tristan, Brazil and some of those from Bolivia and Peru. This is shown by the linear, 2-pinnate, slightly pubescent leaves as well as details of the border cells, vein ends and rhizome indu- ment. Manton and Vida’s report (1968) of a chromosome pubes of n=174 for Eriosorus chelanthoides from Tristan da C A MONOGRAPH OF ERIOSORUS 131 2/3, Tryon sn Tryon 5319, Peru (cu); Bc,Bd, lamina trichomes, X 40; Be upper surface, Bd lower surface, Jameson, Ecuador ee Be, rhizome bristles, T dcop Tryon 5319 (GH). Ca—Cd E. cheilanthoides K E - flexuosus: Ca, portion = ~p soe % BS oO Fy a2 5 S32 oy > se 136 ALICE F. TRYON apoyas, Wurdack 1161 (cH). Cajamarca: Prov. Cutervo, Lépez zo Sagdstegui — 0 (cH); pass s. of Conchan, Stork & Horton 10072 (vs). Libertad: entre Unamen y Bolivar, Lépez b Sagdstegui 3332, Las Quinuas, 3348 a Junin: Con oe Satipo, Saunders 1078 (cH). Hudnuco: Carpish Pass, Ferreyra 8172, 10033 (cu); Hodge 6272 (cH); Pampayacu, Kanehira 143 (cH, us), 175 as). Stork & Horton 9910 (¥, cx); Tryon Featherstone 1792 (¥, c, us). C uadquina, Biie 1, Valle Lares, 1777, Vilcabamba, 2099, La Convencién, 2160 (us); Cerro de Cusilluyoc, Er F, GH, NY, s, us); Pillahuata, Vargas 16784 (cH). Boli Ss. Paz: yt em Tate 326 (Ny, us); Pelichuco, R. S. Williams 2604 (cH, NY, us). Cochabamba: Colomi, Adolpho 106 (vs); Pojos, Steinbach 8367 bis (cH), Cuchicanchi, 6729 (in part F, us). 3. Eriosorus cheilanthoides x Eriosorus flexuosus var. flexuosus Fic. 23C, 24C, Map 13 Gymnogramma flabellata Grev. & Hook. Hooker Jour. Bot. 1:61, = 120. 1834. TyPE: Jameson, in 1832, Ecuador, Surucucho, near Cuenca, road to Naransal, mts. of “Peru,” 9000 ft. He rb, Greville, Jp photo cH; “ailirect: BM!, E! photos cu, K, Ny; Herb. Hook. x! Anogramma flabellata (Grev. & Hook.) Fée, Gen. Fil. 184. Psilogramme aeons (Grev. & Hook. ) Kuhn, Fests. 50 jub. ae Berl. (Chaetop.) 336. 1882. Eriosorus fabellatus (Grev. & Hook. ) core Gen. Fil. 58. 1947. One of the Buchtien collections t of Cardenas, noted below, are mixed with specim E. cheilanthoides which iH formed spores € Pavon and Steere collections more c y m- ble E thoides in their shorter pinnae ess bifurcate segments, straight rachises and dark brown, well formed spores. They may represent a vari closer to E. cheilanthoides than the others included under the above hybrid name Ecuador, Peru and Bolivia. Among rocks in moist situations, at 3200-3600 m. $ EXAMINED: Ecuador. Prov. Cuenca, Jameson 114 (x). I Pen eral ers 171 (c); Panatahuas, Prov. Tarma, Ruiz 48 (B, us); Contumarca, J. B. ae ere (GH, K, Us). Cuzco: Gunther 86 PA). Bolivia. La Paz: U: yungas, , Buchtien s.n. (in part cH), 2735 (s-pa, aa B42 (vs) Hibs, Cérdenas 866 (in part cH), Cochabamba: Colomi, A MONOGRAPH OF ERIOSORUS 137 14. Eriosorus hirsutulus (Mett.) A. F. Tryon, comb. nov. Fic. 25, Map 14 Gymnogramma hirsutula Mett. Ann. Sci. Nat., V, 2:209. 1864. LEcTOTYPE: Lindig 371, Colombia, Cipacon, 2700 m., Herb. Mett. 8! photo cx; isolecto- types: BM!, k!, p! photos GH, us. ymnogramma Karstenii Mett. op. cit. 210. 1864. type: Lindig 15d, Colombia, Bogota, B; isotypes: p! photos cu, us; Ny! - te Psilogramme hirsutula (Mett.) Kuhn, Fests. 50 Jub. Reals. Berl. (Chaetop.) 340. 1882. Psilogramme Karstenii (Mett.) Kuhn, op. cit. 340. 1882. Rhizome repent, the internodes short, ca. 2-4 mm. chomes or bristles rigid, appressed, ruddy to deep brown, at the base 1-3 g cm. long. Petiole subterete at the rhizome, at the apex plane or slightly e len of the id, erect, brown, with a lighter base, the apical cell elongate. Lamina lanceolate, the central darker in the upper portion, the apical cell elongate. Pinnae at es to the rachis or somewhat ascending, ovate or elongate-ovate, equilateral, 0.2- 0 ong, cm. wide, herbaceous, subsessile; upper surface ] i elongate (rarely bulbous in variant); lower surface wi similar somewhat denser trichomes; stalk 0.5-2.0 mm., slightly channeled or terete; pinnules cuneate usually bifid, scarcely imbricate, the margin sometimes retuse; veins ending short of the margin, usually well back of the border, the ends not or The collections of Eriosorus hirsutulus, mainly from the Depart- ment of Cundinamarca, Colombia, consist of specimens with well- formed, light brown or tan spores, and some, included as variants, with aborted or irregular spores. This species resembles Eriosorus cheilanthoides in having linear leaves. However, differences in the shape and disposition of the pinnae, vein ends, spores and the geographic ranges of the two suggest independent and perhaps a parallel evolutionary development of each. Eriosorus hirsutulus may represent one of the lower chromosome levels within the dodecaploid complex associated with E. cheilanthoides. 138 ALICE F. TRYON 1G. 25. Eriosorus hirsutulus: a, habit, X 1/3; b, pinna, X 2-2/3; c, margin with vein end, < 20, all from Tryon & Tryon 6074 (GH); d, e, lamina trichomes, x 40, d x 40 h, j upper surface, , k lower surface, f, g Lindig 371 (pm), h, i Tryon & Tryon 6074 (Ga); j, k E. areates Variant 1, Alston 7237 (Gu); rhizome trichomes, X 10, Lindig 371 (3M). The variants, treated apart from the main citations, can be dis- tinguished most readily by the presence of aborted spores. These plants may be of hybrid origin involving other species of Eriosorus or Jamesonia which are frequently found on the paramos of Colombia. On the basis of my own collections and field records, and from those of other collectors, it has been possible to recon- struct associations of some of the species from Cundinamarca. On Paramo Guasca, E. hirsutulus occurs at a somewhat lower eleva- tion than Jamesonia rotundifolia. The variant with less dissected leaves resembling Jamesonia occurs with E. hirsutulus and E. osus along road banks somewhat below the paramo. Eriosorus flexuosus has also been collected by Killip & Smith at the edge of Paramo de las Vegas and by the Littles near Monserrate. The collection, Lindig 371, with well formed spores is taken as the type of Eriosorus hirsutulus instead of the other collection, Lindig 15e, cited by Mettenius, which I have not seen Colombia. Among rocks on peaty rock ledges and oe banks along road, at 3000-4200 m. A MONOGRAPH OF ERIOSORUS 139 ADDITIONAL SPECIMENS EXAMINED: Colombia. Boyaca: Sierra Nevada del eae Barclay & Juajibioy 7362 (cH). Cundinamarca: Los Ga i ty Alston 1 (BM, cH), Boqueron de Chipaque, 7507 (nM, cu); Paramo de Coachi, ae 2177 (co.); Pennell 2238 (¥F, GH, Ny, a Bogtt, © indig 15c (BM, kK, P); Alto de Cruces Guadalupe, Cuatrecasas 556 L, F, GH, us); Haught 5073 (s-pa); paramo e. of Guasca, Little & Little 7443 (cH, us); Tryon & Tryon 5922, Paramo ak Palacio, 6042, 10 km. e. of Zipaquira, 6073, 6074 (cH). Caldas: Nevado del Ruiz, Bischler 1459 (coL). VARIANTS INVOLVING ERIOSORUS HIRSUTULUS WITH PUBESCENT LEAVES 1. On Paramo Guasca, northeast of Bogota, yee ee occurs in abtindioe on vies higher er, Sy sites, while plants of Erio bgt on and this variant occ an ow si aramo. aaa is pro ably genetically favelveals as show by the e form, strongly inrolled innae and dense tomentum on the bud ma robe of the follow tions. Colombia. Norte de Santander: La Mesita, Pamplona, into. ge a BM, GH); en: sige Bie (c). Cundinamarca: Bogoté, Lindig 15 (3M), 15a (3, BM, P); G , Tryon & Tryon 5922a (cH). 2. The fo lowing ¢ eollection be aborted spores and leaves es dense, rust colored tomentum e rachis and pinnae of the same in Jamesonia d with specime the edge paramo. Colombia. Santander: Paramo de las Vegas, Killip & Smith 15632 (GH, NY, P, s). VARIANT INVOLVING ERIOSORUS HISPIDULUS WITH GLANDULAR LEAVES 3. Specimens of the Little collection cited below are mixed with Jamesonia imbricata var. glutinosa. The glandular character of the variant implicates var. gluti Specimens of Eriosorus flexuosus collected near Monserrate nam de Chico, Cuatrecasas 5501 (coi, F, us); Bogota, 3100 m., Lindig 15b in part, (B, k, Pp); Monserrate, Little ‘s Li ittle 9447 ( CH, us). 15. Eriosorus Lindigii (Mett.) Vareschi, Fl. Venez. 1(2):637. 1969 Fic. 26, Map 15 Gymnogramma Lindigii Mett. Ann. Sci. Nat. V, 2:210. 1864. LECTOTYPE: mse 15b, Megane a ee 3100 m. Herb. Mett. s! in part; pore ige BM! oto CK. collection consists of two elemen applied to ie eatin r leaves, hispid glands and well formed spores. Portions of the collection Lindig 15b represent this species and are found e ing anne B, left three leaves with rhizome and nearly complete leaves of pac gas BM, all three leaves; K, plant with rhi- zome and largest leaf; x, Herb ook. all five fragments; P, central with rhizome. The other ens of this collection which have larger leaves, mostly eglandular fy tiwciainy and fon rted spores have been iden as variant a, under Eriosorus hirsutu hag ngs Lindigii ( Mett.) ata. Fests. 50 Jub. Reals. Berl. (Chaetop. ) 340. 1 140 ALICE F. TRYON Gymnogramma woodsioides Christ, Bull. Herb. Boiss. II, 7:274. 1907. TYPE: Wercklé, Colombia in 1906. Herb. Christ, r! photos cu, us; isotype: spat Rhizome ee the internodes short, the trichomes crispate or rigid, appresed golden to ruddy ae , at the base 1 or 2 cells, the apical cell globose, often wi ces erect or a and spreading, 8-36 cm. of the sai ibe glabrous or spars ers pu ubescent, the trichomes crispate, tan e overed wi pha s rown exudat ot lea small slightly cending ova or a his eae equilat teral or nearl se .2-0.8 cm. argins, usu lly incurve j hepa s of the margin, clavate or rN fas aN ‘ibe o ee a aS) 4 | ; d Fic. 26. Eriosorus Lindigii: a, habit, < 1/3, Tryon & Tryon 6076 = Dy, we x eee c, Margin with sho vein pay 20; 4 trichome; e, lower epidermis; f, g lamina trichomes, f upper surface, g lower Silas all X 40, Lindig 15b (P); h, rhizome trichomes, X 20, Tryon & Tryon 6076 (GH A MONOGRAPH OF ERIOSORUS 141 Eriosorus Lindigii is most closely related to E. hirsutulus and possibly represents a stabilized intermediate of this and Jamesonia imbricata var. glutinosa. These three taxa occur on the paramos around Bogota, but there is no record, at present, of their associa- tion together at any site. The variant, from La Calera, certainly represents an intermediate form involving Jamesonia. The patelli- form shape and bent stalks of the pinnae, their dense glands and irregular margins are all characteristic of Jamesonia. The spores are entirely aborted in this collection. This taxon is recognized primarily on the basis of a unique association of characters found on the specimens cited. There is a preponderance of well formed spores. The plants occur on relatively distantly isolated paramos. Cundinamarca, Colombia. On sandstone ledges or in shade at base of boulders, at 2800-3350 m ITIONAL SPECIMENS EXAMINED: Colombia. Cundinamarca: San bal. J ee. Apollinaire & Arthur 167 (ons; Péramo Guasca, ia sor roog 1921 (c, K, Ny, us); paramo above El Chico, Fosberg 22031 (us); Paramo Cruze Verde, Tryon & Tryon 6076 (co, cH); Usaquén, Uribe Uribe 215 sicle are interme to and Encl involve hybrid tion with Jamesonia imbricata var dlutinase vg? occurs on severa e paramos near Bogota. Cc ia. : Par, La Calera, 6 km. e. of Bogota, Tryon, nam Tryon & Idrobo 6150 feud. GH). 16. Eriosorus aureonitens ( Hook.) Copel. Gen. Fil. 58. 1947 Fic. 27, Map 12 Gymnogramma aureonitens Hook. Icon, Pl. 9: t. 820. 1852 (prior to = cf. — Chron. 1852: 278). type: Lobb, Peru, Veto x! photo cx; fragment ny! e Eriosorus scandens Fée, Gen. Fil. 152, t. 13B, f, 1. 1852 OF ganar December,” see W. T. Stearn, Webbia 17:207-222. 1962). TyPE: Ruiz, i 153 c! erb. hoto GH Psilogramme aureonitens (Hook.) Kuhn Fests. 50 Jub. Reals. Berl. (Chaetop.) 341. 1882. Rhizome repent, compact with short internodes, ca. 2-4 mm. in diameter, the fou sities castes rigid, ruddy to deep brown, at the base bas hone wide, 1-3 cells thick, the apical cell globose. Leaves subscandent ling, 2 cm. long (the longest incomplete). Petiole very senda. subterete at the rhizome, plane or slightly ¢ channeled on the upper surface and about 4 times as broad near the apex, atropurpureous, about 1/3 as long as e lamina, tomentose, the trichomes matted, ferrugineous, the apical cell 142 ALICE F. TRYON si ts subterete or slightly sulcate on the upper surface or plane, atro- pu ous, with dense, matted tomentum, the trichomes Sergius cate. the apical cell elongate. Pinnae strongly ears aa departing from the rachis at an acute angle, or depart ge the iscopic pinnules sometimes larger, 6-18 cm. long, 5-7 cm. wide, ra aioe upper surface cl oO similar to the upper surface, usually denser slone the veins; stalk 10-35 mm. long, terete with dense tomentum as on the rachis; pinnules deltoid, triangu- . ; veins protruding from the margin in a tooth, the vein ends enlarged, broadly clavate at the base of the tooth; border mostly one row, usually interrupted, the cells irregular, those at the vein end shorter, protruding an with numer- ous trichomes eyo to ania on the lamina surfaces. regen ia oe alon own, pro ridges parallel to the tritadiate scar ae irregular tubercles in the angles of ese and adjacent to the usually broad irregular —— flange, the angles projecting, the distal face with several large tubercles This is one of the unique species in that it possesses dense tomentum enveloping the large, scandent leaves. Similar indu- ment occurs in several species, mainly of Venezuela, allied to and including Jamesonia canescens. However, the highly reduced lin- ear leaves of these species of Jamesonia are wholly unlike those of Eriosorus and suggest that there has been a parallel development of the dense tomentum in the two genera. A dense, ruddy tomen- tum also occurs on the smaller, erect leaves of E. Stuebelii which also occurs in northern Peru. There are other resemblances to E. Stuebelii such as the disposition of the vein ends, the epidermal cells and spores. Eriosorus aureonitens is also similar to E. accres- cens in the scandent habit of the leaves and long pinna stalks, and these two species occur in the same region in the Department of Amazonas, Peru. Both E. Stuebelii and E. accrescens are known only from Peru; they occur at higher altitudes up to 3300 m. and their spores are often irregularly formed. Eriosorus aureonitens has the widest range, growing from Colombia to southern Peru and occurring at lower altitudes. The spores are abundant, well formed and evidently are effective in species reproduction. The more limited record and abnormal spore development of the other species suggest that they are possibly intermediates involving hybridization with E. aureonitens. Climbing or scrambling, locally frequent in open places, on moorland, between shrubs, and on clay banks in woods. Southern Colombia to southern Peru at 2750-3150 m A MONOGRAPH OF ERIOSORUS 143 > Or nae 10m». FP RIO 2 # it His tase Fic. 27. Eriosorus aureonitens: a, lamina and upper part of petiole, X 1/ 3; b, pinnule, upper surface with : with t t protruding vein end and trichomes, X 20; e, upper epidermis, the ¢ ; chomes darker; f, lower epidermis, both 40, all from Wurdack 1738 (cH); g, rhizome trichomes, X 10, Hutchison & Wright 5504 (cH). 144 ALICE F. TRYON ADDITIONAL SPECIMENS EXAMINED: Colombia. Tolima: Alto de Oseras, 17. Eriosorus accrescens A. F. Tryon, Rhodora 65:57. 1963 Fic. 28, Map 12 TyPE: Vargas 2921, Peru, Prov. Urubamba, Puyupata, vs! > incomplete ), 5 long. Petiole very slender, subterete at the rhizome, lane or slightly channeled on the upper surface an ut 4 times as broad e apex, atro ureous, ca. about 1/3 as long as the lamina, densely pu nt, the trichomes somewhat matted, tan, the apical cell with an elongate ap elongate-trullate the pinnae oriented in one lane, the central ones longer; the basal pinnae are often withered, 3-pinnate, 15-56 cm , m indeterminate, the apical bud large and densely tomentose. Rachis straight or usually somewhat flexuose, pla: r slightly sulcate on the u surface, castaneous, becoming lighter colored ome elongate. Pinnae ascending, departing from the rachis at an acute elongate-triangular or deltoid, the basiscopic pinnules often larger, 4— ng, 3-6 cm. wi e with s > the angles not or slightly projecting, the distal face with several large tubercles. All of the specimens are incomplete but the long petioles, broad- est at the apex, and the long pinna stalks are suggestive of a scandent leaf habit. In these characters, as well as the general form of the leaves and indument, the species resembles Eriosorus aureonitens. The leaves of E. accrescens are not densely tomen- tose as in the former, and differ in having broader, more strongly lobed ultimate segments and veins ending in a sinus at the margin. A MONOGRAPH OF ERIOSORUS 145 Both species occur in dense shrubby vegetation dominated by bamboo, in the Departments of Amazonas and Puno, Peru. In wooded ravine in shrubby vegetation with bamboo, in shade, Peru, at 28 m ADDITIONAL SPECIMENS EXAMINED ate azonas: entre Leimebamba y Balsas, Lépez et al. 4444 (cH). C uadquifia, Biies 992 (us), Valle de Lares, Montana de Cola, sis (asi ice e Chaco 2135 (us). Puno: Sandia, Weberbauer 733 (B, usM). 18. Eriosorus Stuebelii (Hieron.) A. F. Tryon, Rhodora 65:57. 1963 Fic. 29, Map 12 Gymnogramma — Hieron. Hedwigia 48:219, t. 9, f. 5. 1909. TyPE Stiibel 1058, Peru, Mojon-Cruz, inter Pacasmayo et Moyobamba B! photo sad fragment cu! Rhizome repent, the internodes short, compact, ca. 2-3 mm, long, the trichomes or bristles crispate or rigid and appressed, atropurpureous to deep brown, at the base 1-4 cells wide, 3 cells thick, the apical cell globose. times Leaves erect, 24-28 cm. long. Petiole slender, terete, at the a r br e base, plane or slightly sulcate on supper surface, about 1/3 as long as the lamina, tomentose, the tric ore matted, ferrugineous, the apical cell elongate. tes oedge pe ce yaa e basal yong sometimes smaller than the central o 8-22 cm. long, 2-8 cm. wide, deter- minate, the apical bud ee ee mre tomentose. Rachis stenight, sub subterete or lightly sulcate on the upper surface, spe atted tomentum, the trichomes ferrugineous, crispate, the apical cell clongate. eae slightly wicedding or at right angles to the rachis pon cubes any r cells, the annu cells. ‘own, the oximal face with broad ridges parallel to the triradiate scars, the Rear ually broad, somewhat irregular, the angles si gd many coarse fe on both faces, sometimes very irregular reer This species is known from the original collection made in northern Peru about a hundred years ago, and from a recent one made by César Vargas in southern Peru. The new material is 146 ALICE F. TRYON G. 28. Eriosorus accrescens: a, upper portion of lamina, X 1/3, Vargas 2921 (us); b, pinna, with lower pinnule cleared of indument, X 2/3, Biies 2135 (us); c,d, pinnules, upper surface with pubescence, X 2/3; c, Lopez et al. 4444 (Gu); d, Vargas 2921 (us); d, e, Margin + a epidermis, both Vargas 2921 (us). placed with the earlier collection, mainly on the basis of the sim- ilarity of the leaves which have subsessile pinnules and dense indu- ment. It differs somewhat in having veins slightly protruding, as shown in Fig. 29d, and in this respect resembles Eriosorus aureo- nitens. The larger leaves and long pinnae stalks in that species are perhaps related to their scandent or scrambling habit. The plants occur in dense vegetation at low altitudes. The compact leaf form in E. Stuebelii is probably better adapted to the more open habitats at higher altitudes. The shriveled spores and vari- ability in shape and orientation of the guard cells (Fig. 29, g, i) in these specimens are noteworthy. In woods, Peru, at 3300 m. ADDITIONAL SPECIMEN EXAMINED: Peru. Puno: bajando a Cachi-Cachi, Prov, Sandia, August 6, 1967, Vargas 11834 (cH). A MONOGRAPH OF ERIOSORUS 147 ni AA AAS ¥ ae) Pe ‘t Pe) aap a * Ls ia XA bate te xt ‘a X 1; c, pinna, lower surface with veins, the tomentum removed, X 1; d, e, margins with vein ends and trichomes, X 20, all from Vargas 11834 (Gu); e, Stiibel 1058 (cu); f-i, epidermis, with basal cells of trichomes darker, X 40; f, h upper surface, g, i lower surface; f, g Stiibel 1058 (GH); h, i Vargas 11834 (cu); j, rhizome trichomes, X 10, Vargas 11834 (cu). 19. Eriosorus Wurdackii A. F. Tryon, spec. nov. Fic. 30, Map 16 Rhizoma internodiis brevibus trichomatibus atrofuscis vel nigris ad basim cellulis 14 plerumque 2 latis, lamina elongato-triangularis plerumque 2- vel 3-pinnata apice iecislate gemma glabra, rhachis plus minusve fracti- flexa castanea vel atropurpurea in axillis pinnarum trichomatibus atro- i idis. ae elongato-triangulares rigido-herbaceae, ; is brevibus rigidis, pinn pinnulae ovatae vel deltoideae adaxialiter glabrae a axialiter sparsim pubes- i i ne attingen' i centes, nervi ad marginem ve e ngentes extremis plus minusve clavatis, sporangia plerumque in fascia submarginali, sporae atrofuscae. t. Amazonas, Prov. Chachapoyas, of Molino- 3 : Ww pampa, in rock crevices in Jalca zone, 2200-2300 m., July 31, 1952, J. J. Wurdack 1514 GH; iso US. izome elongate, repent, the internodes short, ca. 4-7 mm. in diameter, the trichomes or bristles rigid, appressed, deep brown to nearly black, at the base 1-4, often 2, cells wide, 1 or 2 cells thick, the apical cell elongate. Leaves erect, 26-46 cm. long. Petiole subterete near the rhizome, at the 148 ALICE F. TRYON oo channeled, atropurpureous, equal to or slightly longer than the lamina, glabrous or with sparse, rigid, erect, brown trichomes, the apical cell elongate. Lamina elongate-triangular, the base broader than the central i id i brown, or the base ing slightly from the Oo ose of deltoid and shallowly lobed; ultimate segments icular or ovate, the E le) 3 ~ or o af 5 2 S Q = = a a is} =) oe “oO ga or ° g 2, ga Es a n ima a ° — o i car, angles not projecting, the distal face smooth within the central areola. SRN RYN HOS? tN we avis Fic. 30. Eriosorus Wurdackii: a, habit with about two-thirds of the petiole omitted, x I/ 3; b, pinna with sporangia and trichomes on acroscopic pinnule ; ¢, margin with ice — % 20; d, trichomes from pinna axil; e, lamina trichomes from sorus; upper epidermis, g lower epidermis, all 40; h, rhizome bristle. 10, all from Wurdack 1541 (gx). ne ens aN A MONOGRAPH OF ERIOSORUS 149 The species, known from this single collection from northern Peru, supplies a possible link with the distinctive scandent species, Eriosorus Orbignyanus. This relationship is shown by the peculiar habit of the pinnae descending from the rachis at an angle greater than 90 degrees, the sori usually forming submarginal bands and the veins often terminating short of the margin. Eriosorus Wur- dackii is regarded as less specialized than E. Orbignyanus on the basis of its erect habit and simpler leaf form. The submarginal sorus bands are unusual in Eriosorus. This, in addition to several other aspects of the plants, such as the firm texture of the pinnae, dark brown trichomes confined largely to the sorus among the sporangia, and the vein ends terminating short of the margin, suggests a connection with the genus Ptero- zonium. Two of the most widely distributed members of that genus, P. reniformis and P. brevifrons occur in northern Peru. A collection of the latter was also made by Wurdack in the same area as this new species of Eriosorus. Pterozonium represents a more specialized genus with once pinnate or simple leaves. It is certainly more closely related to Eriosorus than to other genera, and E. Wurdackii provides a possible link between them. I am pleased to name the species for Dr. John Wurdack, whose fine collections of Eriosorus and the related genera, Jamesonia and Pterozonium from Peru, and the Guayana and Venezuelan high- lands, supply some of the basic data for our knowledge of these genera. 20. Eriosorus Orbignyanus (Kuhn) A. F. Tryon, Rhodora 65:56. 1963 Fic. 31, Map 16 mnogramma Orbignyana Kuhn, Linnaea 36:70. 1869. TYPE: D Onion 209, Bolivia, Cochabamba, Yuracarés, Herb. Mett. 8! photo cu; isotypes B! c! photo cx; p! paratype: Ovens 174, B Lea La Paz, Yungas, Herb. Mett. B! oa GH; isoparatypes: cl, p! photos Gymnogramma prehensibilis Bak. Syn. “Fil ed. 2, 517. 1874. sie Pearce, July, 1866, Bolivia, La Paz, Sandillani, 8000-9000 9000 ft. x! photo P silogramme Orbignyana (Kuhn) Kuhn, Fests. 50 parte heal Berl. zome not seen. Leaves scandent or scrambling, 3 m. long. Lamina ‘hdeae pinnae oriented in one plane, the — ones — than the apical, 4-pinnate (largest puis specimen, ca, 95 cm. long, 18 cm wide), indeterminate, the apical bud seat ’ slightly pubescent. Rachis the lower surface convex, es the upper surface Sealy channe staneous, somewhat lighter near the apex, aeiely pubescent or glabrous, 150 ALICE F. TRYON e triradiate scar, equatorial flange narrow to moderately broad the angles not projecting, the distal face smooth within the central areola. Eriosorus Orbignyanus is similar to E. flexuosus in the scram- bling habit of the leaves. Both species apparently were collected at Yuracares, Bolivia, by D’Orbigny. There are several differences between them, particularly in the shape and the division of the lamina, the spores and the orientation of the pinnules, suggesting that the scrambling habit may be a secondary character which was independently developed in the two species. The orbicular form of the ultimate segments and position of the sporangia in submarginal bands are also characteristic of E. Wurdackii. The larger guard cells in E. Orbignyanus, shown in Fig. 31f, may reflect a different ploidy level than those of E. Wurdackii (Fig. 30g). Eriosorus Orbignyanus is known only from fragmentary portions of the lamina, and it is difficult to reconstruct the com- plete leaves. The rhizomes are lacking in all collections but it is noted in the label data of one collection that they are embedded in mosses. The indument of the rhizome, used for indicating relationships in other species, is probably composed of unspecial- ized trichomes, similar to those found in E. Wurdackii. DOrbigny’s collection 299 from Yuracarés includes some fertile pinnae and has been chosen to typify the species, rather than his collection 174, which seems to be completely sterile. Scandent or scrambling on brush, rhizomes in sphagnum. Co- lombia to Bolivia, at 1400-3800 m. A MONOGRAPH OF ERIOSORUS 151 NAL SPECIMENS EXAMIN Colombia. Santander: Cerro Haught 1961 (cH, us). Antioquia: : Tabac Kalbreyer 1365 (3, x, ple aa Narino: between Santa Lucia and Pasto, 3800 m., Stiibel 264 (B); 3 5) above Sachamate, Ewan 16676 (cH, No, s, US). Ec uador. Azuay: Cuenca, Le Pearce 306 (x) July 5, 1910, Markham Huan f Weberbauer 3514 (B, BM) in: Porvenir, Killip & Smith 25947 (ny, us) aupimayo, Biies 1949, 1950 (us); ca. Hacienda Luisiana, Pro uZzco: u 1 . Convencién, Tr R. Dudley 11240 (cu); Bolivia. Bang 2238 (B, BM, GH, K, NY, US, W), oe NY, us). La Paz: Yungas, Rusby 129, in part 128 Pet Cargadira, R . S. Williams 1111 (3m), Paradiso, 1248 (cu, Ny, us). Cocha- bam eg Incachaca, epragie: 6768 (BM). FP 6 4 sv Mas 16-19, Map ieactes orton, an E. Wurdackii, star. Mar 17, E. insignis. Map 18, E. can Map 19, E. Ewa 152 ALICE F. TRYON Zee ren ies owe nGateeali HR Beaty NN)! Neh Fic. 31. Eriosorus Orbignyianus: a, diagram of pinna rachises and rachis from apical portion of a large leaf, X 1/3, Ewan 16676 (us); b, tertiary segment with veins, 2/3, Biies 1950 (us); c, two ultimate segments with veins, one with sporangia 1.8 submarginal band, X 2-2/3; d, margin with vein end; e, f epidermis, e upper epidermis, f lower epidermis; g, lamina trichomes from upper surface, all < 40, Ewan 16676 (us). 21. Eriosorus insignis (Kuhn) A. F. Tryon, comb. nov. Fic. 32, Map 17 Gymnogramma insignis Mett. ex Kuhn, Linnaea 36:70. 1869. TYPE: St. Hilaire, << Negra, at border of ‘Rio de Janeiro and Minas Gerais s!, photo GH; isotypes: St. Hilaire Cat. n’72 p!, photo cu, Cat. B’458 p!. The holotype a description of the species, a m the Mettenius Her ame eet there is a pencil sketch of part of the lamina and the printed descrip- tion of Psilogramme insign uhn’s i rial, upon isotypes: kl, ny- a ex xl, Pl, ks o cu, us. In the second volume, Glaziou 5321 is also cited an the Psilogramme insi i msgs Kuhn, a re 337. 1882. Gymnogramma ubia (Kuhn) Bak. Ann. Bot. 5:485. 1891 ae Eriosorus Feei Copel. Gen. Fil. 58 1947. Based on pelcembiin scandens A MONOGRAPH OF ERIOSORUS 153 es clear to brown or > the apical cell usually globose. Lamina elongate-triangular, the base usually slightly broader than the central portion, the 0 cm. long, 8-18 cm. wide, determinate, the apical bud small, slightly the basiscopic side, slightly larger, 1.5-8.0 cm. long 1-4 cm, wide, herbaceous to coriaceous; upper surface moderately to sparsely pubescent, the trichomes rigid, brown, or patent, clear or tan, the apical cell elongate or globose; lower i i imilar to those above; stalk 5— long, sulcate, some th decurent lamina tissue; pinnules ovate; ultimate segments orbicular or ovate with several shallow lobes, the ins crenate, usually plane; veins extend to or ly to narrow, Clear with 1-3 rows of elongate cells, n at the vein end irregular, about as long as broad. Sporangia mostly on , the stalk of 1 or 2 tiers of clear cells, the annulus of 19-20 indurated cells, Spores deep brown, the proximal face with narrow ridges parallel to the triradiate scar, the equatorial flange narrow, the 3 angles not projecting, the distal face smooth within the central areola or with a few, coarse tubercles. The large scandent leaves of these collections show considerable variation in the division of the pinnae and pinnule shape but are more uniform in details of the venation, spores and indument. The collection of Santos Lima 417 has especially robust leaves with coarsely lobed pinnules. The cells of the upper epidermis are larger than those of other collections and have slightly undulate walls. The epidermal cell patterns from several collections, in Fig. 32, show considerable variation in size and probably reflect different ploidy levels. Those from the type collection of St. Hilaire are smaller than those of the Santos Lima collection. The scandent, fractiflex leaves with descending pinnae, orbicu- lar ultimate segments and dark spores suggest that Eriosorus insignis is closer to the Andean species, E. Orbignyanus and E. Wurdackii, than it is to the other Brazilian species, E. myriophyl- lus or E. Biardii. The more complex scrambling leaves and broad bristle-like rhizome indument indicate that the species represents 54 ALICE F. TRYON A 2 ey Ye Na aN mM Rags aie at 5 - 32. Eriosorus insignis: a, leaf, X 1/3; b, pinnule, X 1-1/3; c, margin with vein ends and glandular trichomes on upper surface, X 20, all St. Hilaire B’ 72 (v); 4, rhizome small plant, & 1/3, St. Hilaire B’ (P); e-i, lamina trichomes, €,g,i, upper wer surface; e,f, Tryon & Tryon 6701 (cu); g,h, Silveira #62 (Rr); i, St. Hilaire C72 (P); j-q, ermal cells, the basal cells of trichomes darker ; jn, p, upper surface; k,m,o,q, lower surface; j,k, St. Hil 2 (P); + 40; 78 Im, Glaziou 3552 (r); no, Tryon & Tryon 6701 (GH); p,q, Santos Lima 417 (88); "8, rhizome bristles with few elongate rhizome cells at base, X 10; r, St. Hilaire C458 (P); s, Silveira 462 (Rr). A MONOGRAPH OF ERIOSORUS 155 a fairly specialized one in the genus. It is exceedingly rare on Mt. Itatiaia where I found a single colony of a few plants on the planalto. They were in a moist crevice at the base of a large boulder apparently protected from the periodic burning of this high, rocky grassland. Rare, in moist, shaded places at edge of boulders, or in caves. Eastern Brazil, at 1000-2300 m. ADDITIONAL SPECIMENS EXAMINEDS Brazil. Minas Gerais: Serra da Caraga, Alvaro Silveira 462 (p, n); Serra de Thitipoca, Schwacke 12310 (Pv, R). Rio de Janeiro: Therezopolis, Glaziou 89, April 1868 (Rn); Frade de Machai, Brade 15802 (BM, Gc, Ny, RB); Alto do Desingano, Sta. Magdalena, Santos Lima & Brade 13151 (BM, RB); Serra Norte-Vermelho, Sta. Magdalena, Santos Lima 417 (rp); Itatiaia, w. face of Pedra Assentada, Tryon & Tryon 6701 (cH). Sao Paulo: Campos de Jordao, Campos Porto 3108 (BM, RB). 22. Eriosorus flexuosus (HBK.) Copel. Gen. Fil. 58. 1947 Rhizome repent, with short internodes, ca. 4-8 mm. in diameter with rigid, usually appressed, lustrous deep brown to black trichomes, poesia or ae ic e apex or base, 5- 6-pinnate, in the smallest fertile specimen 18 cm. long and 12 cm. wide, in the longest complete specimen 200 cm. gt and 37 cm. t broadest near the rachis), the basiscopic side sometimes larger, 2-33 cm. long, 1-25 cm. wide, herbaceous, delicate or sometimes a more rigid texture; clavate; border narrow, clear or opaque, 1-3 mgat along the edge bulging at the apical end, often protruding in an irregular 156 ALICE F. TRYON e irregular ridges adjacent to the triradiate scar, with narrow to moderately se caietecia) rae the angles not or slightly onsen the distal face usually with a smooth central areola or with few, coarse tubercles, sometimes aborted. Ad Al Fic. 33. Eriosorus flexuosus: Aa—Am var. flexuosus fo Aa, mall lea: h of a small leaf, with fiy alias in detail and rachis o pana > tee | bud, enlarged, Tryon & Tryo 04 (GH); Ac, rhi (cH); Ad, diagram of pi hi nd portion of the rachis, Alston 6 tertiary segment with veins and some sporangia, 1, Tryo ul € segments with veins, sporangia and trich tri hizome bristles, X 10; Ak, Al, Tr ryon oe Tryon 6109 on Am, Alston 6469 (GH). Ba var. galeanus: vhicome scales, X 10, Hinton 14221 (cu A MONOGRAPH OF ERIOSORUS 157 Eriosorus flexuosus has the most extensive distribution of the genus on the American continents. It ranges from southern Mexico to Bolivia, and occurs in eastern Brazil and in the Greater Antilles. It also has the greatest altitudinal range, occurring at 00 m. in southern Mexico and up to 4200 m. in the Cordillera Oriental of Colombia. It has been more frequently collected than other species because it is very conspicuous. The plants are scram- bling or climbing on shrubby growth in the lower montane zone and in low woods bordering paramos. The leaves may attain more than four meters in length, and are usually fractiflex with the pinnae oriented in several planes. The ultimate segments are usually slender and bifurcate but may be broader and cuneate. The collections included in the general citations represent only a portion of the material studied, and consist mainly of the most widely distributed collections. Several variants are included as examples of some of the main deviations from the usual pattern, particularly those which can be associated with other species. To a large extent, hybridization has been a factor in the production of variation. The putative hybrids involving E. flexuosus are treated y formula under the species they most closely resemble. They are also noted in each case under the treatment of the second parent. The record of meiotic chromosome counts of 87 bivalents at meiosis reported here in Eriosorus flexuosus var. flexuosus from Costa Rica is interpreted as a hexaploid level and implies the existence of three lower chromosome levels. The hybrid with E. Warscewiczii from Volcan Pods is proposed on the basis of the associations of plants in the field and the cytological analyses of meiotic cells. There are ca. 174 chromosomes in these, mostly uni- valents as shown in Fig. 2g. The new variety, E. flexuosus var. galeanus, known only from the Galeana district in Guerrero, Mexico, is the northernmost rec- ord for the genus. The plants are especially notable because they have true scales on the rhizome. These structures, shown in Fig. 33Ba, are several cells wide and may be somewhat thickened at the base, but are usually distinctly laminar above. The leaves are somewhat more pubescent than in var. flexuosus, but are generally similar to that variety in the form and division of the pinnae. For this reason they were not illustrated. Eriosorus flexuosus represents one of the most derived species in the genus as is evident from the complexity of the leaves, 158 ALICE F. TRYON bristles and scales on the rhizome and light colored spores. Simi- larities with other species such as E. Ewanii and E. Biardii suggest that these species may be intermediates involving E. flexuosus. The large, scandent leaves of E. flexuosus are also similar to E. glaberrimus, but other differences in the spores and rhizome indument do not support a close relationship. The shape of the ultimate segments, their borders and vein ends, as well as the broad bristles on the rhizome and light spores are similar to E. hirtus. The more complex leaf form of E. flexuosus has probably evolved from a simpler one similar to that of E. hirtus. KEY TO THE VARIETIES OF ERIOSORUS FLEXUOSUS Rhizome with lustrous deep brown to black trichomes * bristles; leaves scandent or scrambling and herbaceous or more rigid in are 22a. E. flexuosus var. flexuosus Rhizome with light brown or tan scales, leaves ei and dice: hevacecal scab iggiiniar nice OO a ES enn ile 22b. E. flexuosus var. galeanus > SS mil hii Dy Holdridge 7925 (cH). Cartago: o onti Cuatrecasas & Garcia Barriga 10090 (cox, F, GH, Cu Sig et al. 12675 (cH); Paramo de Rodded Killip © § ‘Smith 18678 (GH, Ny, Us), Paramo de Santurban 19607 (coL, GH, NY, us). Santander: n. of Velez, "Ripe 15668 ; Boy de Belén, Barclay & Juajibioy 7660 ba Giese de age 0 elgg 801 (cH undinamarca: U Usaquen, rrr ton 7: o (eM, cH); M ontserr e, Ewan 6144 (¥, Ny, s, ve) Bogota, india 34 (x, ou, x, Pp); Schiefer 517 (cu); Péramo de Guas Tryon & Tryon 5926 (cu), 7 km. sw. Sibate, 6100 (cH). Tolima: Vole anc, Killip & Hazen 9490 (cu, us). Huila: Comissaria de Caqueta, —— as 8434 (us). Bolivar: Fee a Pennell 4457 (¥, GH, x, us); El San i de la ae 1726 (us); Las Palmas, les Hoy 6548 —o apt — Ss). O: ‘ Chile, bay sar 10611 (yy). Imbabura: assy Acosta Solis 8275 (¥F). ichine Oro, E4617 (ny, us). El Ores Zerum ap Rapesco 2 E2133. foe ee Santiago-Zamora: between Sevilla de ri ond Mendez, Camp E1616 (Ny, us). Loja: se. of Loja, Espinosa E1570 (cu, ny). Peru. Cajamarca: La Pucarilla, Lopez & Sagdstegui 5458 (cH). Amazonas: below Chachapoyas, Stork & Horton 10393 (F, c, Kk). Cuzco: Cerro de — co 13941 (¥, cH, ny); Pillshuate, Vargas 16754 (cH). Lechler 2247 (B, E, G, K, P, w); e re Ayapata y Kainslnyoe, Vi Vargas 10 10750 (c w). ragua: eas Tovar, Fendler ae GH, “3 P, ay Moritz “139 (a, a Lara-Trujillo: Paramo de los geen Barc lay & Jua saat jibioy 10285 cc Trujillo: above nage Alston 646: were e. a: Sierra Neva 162 ALICE F. TRYON (vEN). Tachira: s. of Alquitrana, Steyermark et al. 101061 (cH). British Guiana. Roraima, im Thurn 159 (x, us); Jenman, 1894 (£, Ny). Brazil. Espirito Santo: Cerro Batatal, Glaziou 15739 (Bs, se om ds ~ se Se Republic. La Vega: Loma Rosilla, Fuertes 1784 (£, H, K. : e oe of baa Maile ios 721, 737 (cH). Santiago: aioe. Eicon 13851 (8B; c, arranged in two Ripe ego on leaf indument. Specimens included under numbers 2-6 in the series are mostly fragmentary portions, apparently from large leaves. These are ieithouit petiole or rhizome and therefore are especially difficult to identify. VARIANTS WITH PUBESCENT LEAVES AND USUALLY SIMPLE TRICHOMES n his treatment of Psilogramme Maxon nana P. villosula and pres it from closely related species on the basis of copiously short- villose leaves. He cited only the type. This and other iiemens noted below can be distinguished by this character as well as somewhat broader ultimate than a sual for glands and trichomes on the leaves, and Maxon indicated that it was poe another species. It is likely that E. congestus, which has dense pu on the leaves, and is in the same range, may implicated . hybridization has occurred. Costa Rica. San José: E] Paramo region n du General, Pittie 10452 (us); Cerro de las Vueltas, Standley & Valerio 43563 — — San Isidro de El General, pigeon as one (cH); Williams . al. 24403 (F); TitG ee 1 and with rae brown spores are possibly in termediates derived rye hyb iia : e the s this material may be clarified. Venezuela. TAachira: Paramo de Tama, Steyermark 17314 (¥, cH); Steyermark & Dunsterville 98582 (cH). Colombia. Norte de Santander: Péramo del Hatico, Killip & Smith 20628 (CH, Ny, Us). Antioquia: Alto Capiro, Ewan 15763 ( ). Cundinamarca San Miguel, Cuatrecasas ¢ Jarmillo 12037 (us). Cauca: Mount el Derrumbo, nsagie 7508 (cH, a a us). Ecuador. Azuay: Sevilla de Oro, Ca E4770 Y, us). Peru. Caj : Socota, Stork ¢x Horton 10132 (¥, x). Bolivia. Rio Juntas, O. Ranken ‘April 1892 (B, NY). VARIANTS WITH GLANDULAR LEAVES 4. The material cited below differs from the strongly scandent specimens A MONOGRAPH OF ERIOSORUS 163 under Variant 1 because of its more aime habit. The more compact and densely glandular rise suggest that congestus may be involved if hybridization has occurred. hats Tia. ‘San José: n. of San Isidro del pea Mex ir fp 2990 (F, The plants of the cited colbseaion have well formed tan spores and the lamina texture is more delicate bose an other variants from Colombia. Epidermal cll — and patterns, as shown i g, h, are quite uniform. Colombia. ander: Paramo de las Pussita. Killip & Smith 18195 (BM, COL, GH, NY, wes The ce collection is extremely fragmented but quite vanes in shape of the broad, cune ape of the ultimate segments. Eriosorus ; landulosus occurs on the same department in Ecuador as this variant. A putative hybrid with E. flexuosus is sed under that taxon. This collec- propo col tion differs from that in its scandent habit. Ecuador. Loja: André 4514 (F, GH, K, NY) PUTATIVE HYBRIDS INVOLVING ERIOSORUS FLEXUOSUS Eriosorus flexuosus var, flexuosus x Eriosorus Warscewiczii Eriosorus Warscewiczii is frequent at the high altitudes near the crater on Voleén Pods. Somewhat lower, in the cutover forests, uosus var. uo- h spores has been desi at by the letter a under the same number. Costa Rica. Alajuela: ic road, below Pods crater, in turfy humus, 2500 m., Tryon & Tryon 7011, 7011a (cH). Eriosorus flexuosus var. flexuosus Eriosorus paucifolius riosorus Lasseri Vareschi, Acta Bot. Ven. 1:94, f. 6. 1966. Type: Vareschi & F a. 4945, Venezuela, Bolivar, Cerro Auyantepui, vEN (pinna frag- ments see The nail that I have examined of the type collection of Eriosorus Lasseri represents only two fragmentary portions of pinnae = a drawing of a “rhizome scale.” This material ogra of two elemen ts. ts. One most closely resembles E. paucifolius in its and pinnule division and is eglandular. The other is glandular. Both are generally similar to more complete collection cited below , all of whi ch have erect leaves with flexuos ose ises. The 164 ALICE F. TRYON as well as its occurrence on the massifs in the i” e of Bolivar. Venezuela. Bolivar: Cerro Auyantepui, Vareschi & Foldats 4857 (vEN); below El Liberator, Secure 93983 (GH, VEN); Roraima, Steyermark 58754 (F, Us). British Guiana. Mt. Roraima, McConnell & Que elch 9 (K, Ny). The la et specimen cited below is much aaa but the scandent leaves resemble E. flexuosus. It differs from the previous collections in having densely glandular leaves and a copious exudate on ands. The collection on resents type of E. flexuosus from the beans i Caracas. liv U: 22b. Eriosorus flexuosus var. galeanus A. F. Tryon, var nov. Fic. 33B, 34B, Map 20 Rhizoma internodiis brevibus squamis vel setis ee fuscis vel fulvis, lamina elongata plus minusve oblongata 4- vel 5-pinnata pinnis in planis 1 vel 2 dispositis apice acuminato indeterminato gemma ‘ae rer pubes- centi, pinnae delicate herbaceae adaxialiter et abaxialiter trichomatibus sce, nervi ad marginem attingentes non vel leviter dilatati, sporae pallide exico, Guerrero, Puerto Gallo, del Cerro Teotepec, August 11, 1964. tated. 18594 cu; isotype: NY. Rhizome with lax, crispate, light brown or tan scales or thickened bristles, lighter than the thizome surface, at or near the base 3-11 cells wide, 1-3 . ith acuminate. Rachis pubescent. Pinnae ascending and spreading, not appressed to the rachis, delicately herbaceous with clear trichomes on surfaces; veins extending to the sen at not or "slightly enlarged. Spores light rown with a narrow equatorial flan al species of Eriosorus hive rhizomes with bristles or thickened e . Joba. The leaves of var. galeanus are ah illustrated as they are pila similar in detail to those of var. flexuosus. ield data accompanying the collections bu axa plants of Guerrero represent the most northerly record for the genus and it would be of interest to know if they geographically replace var. flexuosus or grow in association with it. The Hinton collection lacks the rhizomes but it is included here because of the similarity of the light — spores, pubescent rachises and the veins terminating at the segment margins. The variety is named for the district Galeana, in the state of Guerrero, in which all of the collections have been made. Terre strial, sometimes scrambling on shrubs, growing between shrubs in oak and pine —_ a a at 2450-3025 m. DITIONAL EXAMINED iene yin rrero: Piedra Ancha, Hinton 14221 py i a Teotepec, 14309 (Fr, us); Cerro Teotepec, 2 km. ne. del Campamento El Gallo, Ssloneehs & “MeVaugh 125 (Ny). A MONOGRAPH OF ERIOSORUS 165 23. Eriosorus Ewanii A. F. Tryon, spec. nov. Fic. 35, Map 19 Rhizoma plantae juvenilis internodiis longis trichomatibus fuscis ad basim cellulis 1-3 plerumque 1 latis, lamina elongata oblongo-trullata vel i es atae v oblongo-rhombicae rigido-herbaceae adaxialiter et abaxialiter glandibus capitatis exudatiferis, pinnulae trullatae segmentis ultimis gracilibus bifidis profunde lobatis, nervi ad marginem attingentes plerumque dilatati extremis callosis incrassatis, sporae atrofuscae aliquando irregulares. TYPE: Colombia, N ? in ruddy brown, at the base 1-3, usually 1 cell, the apical cell elongate. Leaves erect, or twining, 23-4 . long. Petiole terete, or subterete, atropur- pureous or lighter, ca. less than half as long as the lamina, glandular, the , the central ones often longest, 4-pinnate, 9-38 cm. long, 2-8 cm. wide, indeterminate, the 5 a u : actifl neled, atropurpureous or castaneous, densely glandular, the glands with long, clear basal cells and globose, yellow apex. Pinnae ascending at an acute angle and appressed to the rachis, usually imbricate, elongate-ovate a. imilar, less dense indument; stalk 2-6 mm. long, sulcate on the upper surface, glandular; pinnules elongate-ovate; ultimate segments usually bifid, cuneate, with slender lobes, often longer than broad, the margins retuse or a u narrow, the angles prominently projecting, the distal face with coarse tubercles within the central areola, sometimes irregular or aborte The dense glandular indument and thickened vein ends are distinctive features of these plants. Their relationship to E. flexu- osus is clearly shown by the general form of the lamina and ulti- mate segments. The oblique orientation of guard cells in the epidermis shown in Fig. 35f, the irregular sporangia and frequent aborted spores suggests that these plants may represent an inter- mediate involving E. flexuosus in some hybrid combination. The 166 ALICE F. TRYON collections are from paramos at high altitudes. The reduced form and glandular lamina of the specimens suggest possible connec- tions with Jamesonia. Both J. pulchra and J. cinnamomea have been collected on Volcan El Galeras; the latter, with glands and dark spores, is close to Eriosorus. On the basis of the relatively wide distribution of these plants of E. Ewanii in southern Colom- bia it appears that they are effectively reproduced by spores. It is a special pleasure to name this for Professor Joseph A. Ewan in recognition of his contributions to our knowledge of South American plants which has been greatly enriched by his collections and his particular interest in ferns. rowing in tufts among low bushes, on cannes and upper paramo scrub. Southern Colombia, at 3400-3765 m ADDITIONAL SPECIMENS EXAMINED: Colombia. Cauca: Quebrada del Duende, Camis 19145 (a, F, us); Narino: Putamayo, Pdramo el Tabano, Garcia Barriga 4527 (cox, us): woods near Pasto, Jameson 476 (c, BM-in iE 24. Eriosorus Biardii (Fée) A. F. Tryon, comb. nov. Fic. 36, Map 18 Anogramma they Fée, Crypt. Vasc. Brés. 1:241, t. 77, £. 1. 1869. TYPE: Glaziou 3331, Brazil, Serra sige ies ce ‘aes Janeiro, June 1869, Herb. Cosson Pp! photo cx ; iso a, eS us! The second collection at Paris has a ptiid label ero that it See om the Herb. Glaziou, oes the date 27 May 69, which er utes that the work of Fée published in or later than June oie Gymnogramma ext. ity Mart. Fl. Bras. 1(2):599. 1870. TYPE: Glaziou 3331, Brazil, dos ree Rio de Janeiro, x! se i Biardii (Fée) Kuhn, Fests. 50 Jub. Reals. Berl. (Chaetop. ) Rhizome repent, compact with short pines singe mm. in — ) 4 ° o ne , her aceous sparsely pubescen t to pea ‘dabrow, the trichomes clear, oe usually elongate; A MONOGRAPH OF ERIOSORUS 167 f Fic. 35. Eriosorus Ewaniti: a, diagram of pinna rachises and portion of the rachis, ower eé trichomes from lamina; g, er surface; h, lower surface, all X 40, from Ew 16316 (GH); i, rhizome tri oe of young plant, iar with elongate cells of rhizome at base, 20, Cuatrecasas 19145 (a). weed = angia, the apical cell elongate; stalk 2-4 mm. long, sulcate surface, = ridges continuous with ose on the rachis, cuneate, gay bifid lobes as long as or slightly ass San broad, the i i ins ending short of i ma retus ually incurved or plane; v ndin the margin, slightly enlarged (the inal n obscure on the abaxial surface); arrow, clear, 1 or 2 rows of elon cells, marginal ones protrudin e apical end, those at the segment apex about as long as broad and slightly protruding. Sporangia most abundant on base ultimate and on the penultimate veins, the stalk short, of 1 or 2 tiers of clear cells ; _ of 16-20 indurated cells, Spores rown, the proximal face with dense tubercles usually coal t > ace broad es acc el to the triradiate scar, with a narrow —— pues: moo > The lamina tissue is herbaceous and not unusually thickened, but the vein ends are submerged on the abaxial surface. In the shape of the ultimate segments, oc ors borders, and in lamina indument the species is similar to E. flexuosus. It is readily dis- tinguished by the smaller, linear leaves and predominantly straight, dark colored rachises. In the suite of specimens collected by Brade 19246, some leaves have slightly flexuose rachises and 168 ALICE F, TRYON Ry ii - Bs fia Hy We d orus Biardii: a, habit with some ocr in yn and —_ of pes ong 20; a eS eat Prag og! ne le & 16515 (Gu 40; £ ic H); h, rhizome bristles with small basal cells from rhizome epidermis, X 20, Brade 19246 (Rp). the ultimate segments are strongly bifid. In these and other col- lections the width of the lamina is especially variable. The geographic associations are useful here because E. Biardii occurs in Espirito Santo and the only Brazilian record of E. flexuosus is from that state, made by Glaziou in 1884, On the basis of this geographical association and morphological similarities of these A MONOGRAPH OF ERIOSORUS 169 species, E. Biardii is considered most closely related to E. flexu- osus. In partial shade, between shrubs. Brazil, at 2000 and 2100 m. ADDITIONAL SPECIMENS EXAMINED: Brazil. yes Santo: Castelo, Brade Cali (RB). Rio de pa si nee ry Brade 9523 (x), Serra dos Orgaos, o dos Antas, 16515 (BM, GH, RB, S, US); Peres Glaziou 78 in rape 1868 (Rr). 25. Eriosorus glaberrimus (Maxon) Scamman, Contrib. Gray Herb. 191:85. 1962 Fic. 37, Map 21 Psilogramme glaberrima Maxon, Bull. Torrey Club 42: ae 1915. TYPE: Tonduz 12531, Costa Rica, La Palma, September 4, 1898, uv ae ie Pl; paratypes: from the same ‘place, Brade, March 17, 1908, on fe s!, s-pal; Maxon 498 us. cymnogramma glaberrima (Maxon) C. Chr. Ind. Fil. Suppl. Prélim. 19. 19] Rhizome repent with short internodes, ca. 3-8 mm. in a the tri pian e ce capris or rigid, sind to dee _ brown, at the base 1-7 eparting ang greater than 90° (the pinnae rachises fractiflex, the pinnule ake: strongly curved, forming arcs ascending toward the pinna phe aig omg or peal one herbaceous or some papyraceous; upper surface ually glabrous, the young leaves with a few clear trichomes, the asics cell elongate; lower surface glabrous or with few trichomes aioe the sporangia, similar to those above; stalk 1-4 cm. long, prince on the ups r surface, the ridges continuous with got of the rachis, glabrous; pinnules elongate-trian e bifid, cuneate, with slender t lobes about indurated cells. Spores deep brown, the proximal face with peered sculptured bands parallel t Ce ee triradiate scar, the al flange moder 170 ALICE F. TRYON ately broad, the angles not projecting, the distal face with a few coarse tubercles within the central areola, or smooth. The scandent leaf form of Eriosorus glaberrimus somewhat resembles that of E. flexuosus although there are basic differences in the orientation of the rachises, in the form of the leaf apex and disposition of the pinnules. The plants occur in wet forest and are ecologically more restricted than E. flexuosus. Meiotic cells of plants from La Hondura have 87 bivalents at diakinesis. This is regarded as another hexaploid similar to other Costa Rican species. It is the only species, among six in Central America, with- out marked affinities with species in the Andean region. On the basis of the characters noted above, distinguishing it from E. flexuosus, as well as the ultimate segments with broader, spreading lobes, and the dark spores, it seems more likely to have originated from an element formerly more widely distributed than from species now in Costa Rica. Scandent or subscandent in wet forests or on moist road banks in the lower montane zone. Nicaragua and Costa Rica, at 1230- 2300 m. ADDITIONAL SPECIMENS EXAMINED: Nicaragua. Omotepec, C. Wright (cH, K, us). Costa Rica. Cob Blanco, We ) Heredia: Vara Blanca, Haupt 205 (us); slope of Volc4n Barba, Scamman & re 3 : sé: o. p, s-PpA); Max & Harvey 7940 (s-pa, us); at 1510 m., Tryon & Tryon 7061, 7064, 7065, 7066, 7067, 7068 (cu); Cola de Gallo, Stork 1952°(us). Cartago: Santa Clara de Cartago, Lankester, 1930 (us); La Estrella, Standley 39424 (us); between mpalme & La Sierra, Tryon & Tryon 7058 (cH); above San Isidro, Weber 6014 (cx); near La Sierra, L. O. Williams et al. 28046 (F). PUTATIVE HYBRIDS INVOLVING ERIOSORUS GLABERRIMUS Eriosorus glaberrimus Eriosorus congestus La Palma, the locality of the specimen of E. glaberrimus, is now largely cleared and the land is used for grazing. However, there are still a few scattered trees and patches of woodland, pecially some distance from the main roadway leading to La Hondura. We found several plants of E. glaberrimus there with scandent leaves nearly four meters long. In pen areas, on and about the bases of old tree stumps, congestus was abundant. The i tee wi a scandent with elongate leaves. The rachises are slightly flexuose, not at all arc and have and cun gments ar to those of E. congestus. Unfortunately, the sporangia were too mature for cytological fixation, and the spores were aborted. Costa Rica. San José: La Palma, on road to La Hondura, 1510 m., Tryon é Tryon 7062 (GH). A MONOGRAPH OF ERIOSORUS 171 ELAN A iy ace Yi fh a co fh sa UN ALN \\ A S x g h others, a panne of the ala Hee OL ph 2 fe ae shicat ted. enlarged; c, i i i from Tryon tertiary segment with veins and some sporan all Tr Tryon 7061 GH); d, two ultimate segments with veins, and Trangia on one, 2-2/3; -¢, f, margins on terminal port f lobes with vein ends, ,e, Brade 84 Pat f. — & Tryon-7061 (Gu); & h, epidermis; g upper epidermis, h lower epidermis; i, trichome from sorus, all X 40, Brade 84 (s-PA); j; 2 se ome bristles, elongate re of i at base, X 20, Tryon si Tryon 7058 (GH). DUBIOUS AND EXCLUDED NAMES riosorus Lechleri (Kuhn) A. F. Tryon, Rhodora 65:56. 1963. TYPE: ae 2262, Peru, shine a Gavan, ! photo cH. . (Gymnogramma Lechleri Mett. ex ex Kuhn, Linnaea 1869, Psilogramme Lechleri (Kuhn) agp Fests. 50 Jub. Reals. Berl Neto) 339. 1882), A further study of 172 ALICE F. TRYON Andean Eriosorus results in the conclusion that the single, ae leaf collected by Lechler cannot = ntified with any known species. Eriosorus Ruizianus Fée Pi Se, t 13, £29, 1852— Pityrogramma ferruginea (Kze. — Gymnogramma dom ingensis Bak. Ann. Bot. 5:485. 1891. type: Hort. Bull. $29, 1875, Santo Domingo, Alto Carusal, 7000 ft. k! photos cH, us an fragment. It is quite possible that the three incomplete leaves which represent this name may be from a cultivated plait because the e petioles are abnormally thickened. William Bull was a ortichtenvalist growing orchids primarily, in = sane Gym ymnogra: glandul lifera Hieron. Hedwigia 48:217. 1901. Type: Stiibel 299, Ccleenhia. i. inter Rejoy et Santiago, s! photo cx. The vein ends terminate short of the argin and suggest the specimen may be a variant form of E. hispidulus, but I cannot pov it there with confidence. ymnogramma hirsutula Mett. var. glandulosa Hieron. Hedwigia 48: 220. 1909. tyPE: Stiibel 187, Colombia, Rio Pae es, Bl Bier O GH. This collection ars to represent a hybrid between Jameson A linear leaved species of Eriosorus but I ee cial ently identify th material as a species of either genus. oem, Luge Ettinghausen, bigaet ae bie neetyes 56, t. 31, f. 5 Wien. 1865, nud. The figure is wholly inadequate to meet t th sie seinem of “Arti cle 44 of the Code of Namenelahic. nogramma laserpitiifolia Kze. Bot. Zeit. 3:285. 1845. Type: Moritz 39 Fa 79 (sterile) Venezuela, Caracas. The Moritz collections have not been seen but the oe specifying flexuous sathiate suggests that they may represent E. flexu moan Tita i Hook. var. glabriuscula ee. eds isotype c! photo cu. The label notes that the specimens were oe schivted grow- in shoved situation whic vc account for the unusually thin leaf texture and slightly elongated internodes. The dark costa and compact form of the pus e with bicolorous pe tes seem to relate the specimens to E. rufescen 2:18. 1900. Bas Satake Regnelli na er, ¥ 2 1, t. 43, 0 auieh is Cheilanthes. Christ cited Schwacke 12745 which is E. Sellowianus, but the combination made is exclud Eriosorus ramma subscandens S : Quitensis, 401 3 4 iro -2: VS. TYPE: Sodiro, Ecuador, Volcan Corazén. On the basis of such characters 7 quadripinnatifid fronds, a flexuose rachis and linear ultimate segments, note in the description, the nam me may represent E. flexuosus v. LITERATURE CITED 960. The Schizaeaceae: The gametophyte of Mohria. Phytomerphology 10:351-36 1962. The Schizaeaceae: The gametophyte of Anemia. Phyto- morphology 12:264-288. : Bower, F. O. 1928. The Ferns. Vol. 3. The Leptosporangiate Ferns. Univer- sity erie Cambridge, En f. CurisTENsEN, C. 1938, Filicinae, in Manual of Pteridology. Martinus Nijho The Hague. ATKIN: —_———__ ____. A MONOGRAPH OF ERIOSORUS 173 ponies eee “ B. 1947. Genera Filicum. Chronica Botanica. Waltham, Massa- stare N. “A. 1827. Prodrome de la famille des fougéres. Mém. Soc. Linn. Paris 6:171-337. Scioaua. G. A. 1901. Beitrige zur Kenntnis der Morphologie und Ana- tomie der Genera came a ex is, Gymnogramme und Jamesonia. Dissert. Univ. Miinch. M Erptman, G. 1957. Pollen air Spore Morphology. Plant Taxonomy. Almqvist & Wiksells. Stockholm Esau, K. 1953. Plant Anatomy. John Wiley & Sons, Inc. New Y: FEE, M. ry 1852. Exposition des Genres ad la Famille des ee . Fam. Foug. 5) Paris & Strasbou Raiaiee, U. 1960. Pleistocene ievelaneaen of vegetation and climate in Tristan da Cunha and Gough island. Univ. Bergen Arb. Naturv. 20: VAN DER HaMMEN, T. & E. Gonza.es. 1960. Upper re ig and holocene climate and vegetat ion of the “Sabana 3 Bogota” Colombia, South America. Leidse Geol. Meded. 25:261-3 Hooker, W. J. & R. K. Grevitie. 1827-1831. get Filicum. London Hooker, W. J. & J. G. Baxer. 1865-1868. Synopsis Filicum, London. Ed. 2. anit: London. Karsten, H. G. 1859-1869. Florae Columbiae. Berlin Konpo, “T. 1962. A Contribution to the Study of the Fern Stomata. Bull. Shizuoka Univ. Fac ulty Ed. 13:239-26 Kuun, M. 1868-1869. Reliquiae Mettenianae. Linnaea 35: :385-394; 36:41- 149. —————~—~—. 1882. Die Gruppe der Chaetopterides unter den Polypodiaceen. Fests. 50 Jub. Reals. Berl. (Chaetop.) 323-384. Kunze, G. 1846. Farrnkrauter. Leipzig. Lanjouw, J. & F. A. Srarvev. 1964. Index Herbariorum. Reg. Veget. 31:1- an D. B. 1967. Preroxonium, in Maguire, The Botany of the Guayana Highla hea T Manton, I. 1950. Pioblens of Cytology and Evolution in the Pteridophyta. i d. is Roy. Soc. B 170:361-3 ities W. R. 1915. The North American Species of Psilogramme. Bull. :7 Metcatre, C. R. 1960. Anatomy of the Monocotyledons. 1. Gramineae. Oxford, Clarendon Press MeTTENIUus, G. 1864, Filices. In Triana & Planchon, Prod. Florae Novo- Granatensis Ann. Sci. Nat. V, 2:193— MicxeL, J. T. 1967. cp Phylogenetic Position of Anemia colimensis. Amer. Jour. er aes Momosg, S. 1964. The SS Piaticn of Ceratopteris. Jour, Jap. Bot. 39:225- Ocura, Y. 1938. Anatomie der Vegetationsorgane der gg a in Linsbauer, Handbuch der Pflanzenanatomie 7(2). a. Petit-THouars, L. = A. pu. 1808. Esquisse de la flore ae Tile de Tristan cugna. Pari Picui-SERMOLLI, R. ol G. 1966. Adumbratio florae Aethiopicae 13. Hemio- nitidaceae. "Webbia 21:487-505. a} Scamman, E. 1962. The Genus Eriosorus in Costa Rica. Contrib. Gray Her 191 81-89 174 ALICE F. TRYON Swartz, OLor. 1806. Synopsis Filicum. Kiliae TrYON, As F, 1962. A Monograph of the een Genus Jamesonia, Contrib. Gray Herb. 191: 109-197. ———————. 1963. Notes on the Fern Genus Eriosorus. Spars 65:56-57. ----—-——— . 1965. Paraphyses in the Ferns. Taxon 14:2 966. Origin of the Fern Flora of Tristan ‘a ete Brit, Fern aes 9: 26 ———————. 1968. Evolutionary studies in a group of Costa Rican Ferns. Abstr. Amer. Journ. Bot 35-736 TRYON, R. M. 1960. A sane of some terms relating to the fern leaf. Taxon 9:104—109. ———————. 1962. Taxonomic fern notes 2, ee (including Tris- meria ) Pie gaits Contrib. Gray Herb. ———————. 1964. The Ferns of Peru. Be siesoas atch. Gray Herb. 94:15 ; Tscuupy, R. H. & B. D. Tscuupy. 1965. Modern Fern Spores of Rancho Grande, apres ren Bot. Ven. ALKER, G. 196 A Cytotaxo nomic ou rvey of the Pteridophytes of mate Trans. ov Soc, Edinburgh 66: 169-237. Unverwoop, L. M. 1902. American Ferns 4. The Genus Gymnogramme of the Synopsis Filicum. Bull. Torrey Bot. Club 26:617-634. A REVISION OF THE GENUS MENKEA EvizABETH A. SHAW There are approximately fifty endemic species of Cruciferae in Australia. Many were first described as species in genera other- wise extra-Australian. They have since had a varied nomenclatural history, being transferred from one genus to another, until O. E. Schulz (1924, 1933) described several new genera to accom- modate them. Some, however, have always been placed in genera entirely Australian, one of which is Menkea Lehmann, now including six species of small winter- and spring-flowering ephemerals of central and southern Australia. Most of the early Australian botanical collections were made by English and French explorers, but in 1838 a German collector, Johann Ludwig Preiss, went to Western Australia, returning three years later with extensive collections of plants and animals from the southwestern part of the then Swan River Colony. The plants, finally listed under 2718 numbers, were turned over to various European specialists for study with the results edited by J. G. C. Lehmann of Hamburg and published from 1844 to 1848 as Plantae Preissianae. The treatment of the Cruciferae (Vol. 1:257-262) was prepared by Alexander von Bunge and published in December, 1844 or January, 1845, but Lehmann, who was director of the botanic garden at Hamburg, grew some plants from seed brought back by Preiss and published a description of a new genus, Menkea, and one species, M. australis, in the Index Seminum of the garden for 1843. Lehmann offered no suggestions concerning the affinities of the genus except to remark “nov. genus Cruciferarum e Com- melinearum tribu,” a slip corrected by Bunge in his treatment to “e Camelinearum tribu.” Their concept of the Camelineae was probably that of de Candolle and included genera in which the siliques are completely dehiscent and not compressed contrary to the septum, and the embryos notorrhizal. Bunge remarked that Menkea is a very clearly defined genus, “affine ex characteribus Orobio et Eudemati, ex habitu Stenopetalo. . .” and went on to point out that it differed from the first two genera by the “quad- riseriate” seeds and the habit, and from Stenopetalum by the unilocular siliques and petals that are not elongated. Orobium Reichenb., now generally included in Aphragmus, and Eudema resemble Menkea only superficially in that the siliques may be eseptate. : 176 ELIZABETH A, SHAW The first two species described in Menkea, M. australis and M. draboides (Hook.) Benth., have small oblong or obovate siliques which are strongly compressed in the plane of the replum so that the valves are nearly flat; the septum is much reduced or absent and the ovules are biseriate and very numerous. Menkea draboides was described in 1844 as a species of Stenopetalum by Hooker, who apparently did not then know of Lehmann’s publica- tion of Menkea. He stated that in spite of the eseptate siliques he was reluctant to separate the species from Stenopetalum, that is, from S. lineare R. Br. ex DC., which is, however, very different in habit and has nearly cylindric, few-seeded siliques and greatly elongated petals, and from his own Stenopetalum procumbens which is Menkea australis. In 1874 Mueller described M. sphaero- carpa and remarked, “Speciem . . . a genere removere nolui propter valvas fructuum turgentes, quia enim Cochlearia species siliculis tum planis tum turgidissimis includerit”; since then it has been accepted that Menkea includes plants both with compressed and inflated siliques. The genus, as now delimited, consists of a group of species characterized by small compressed or inflated siliques in which the septum is reduced to a very narrow rim or completely gone and the ovules are biseriate and numerous. Schulz (1936) placed Menkea, including only M. australis, M. draboides and M. sphaerocarpa, in subtribe Brayineae of the Sisymbrieae which is distinguished from subtribe Camelinineae [sensu Schulz] by the leaves being not amplexicaul and the seeds not mucose. He put Stenopetalum into the monogeneric tribe Stenopetaleae which essentially differs from the Sisymbrieae only by the erect calyx and elongated petals. I am reluctant to offer any opinions about the relationships of Menkea to extra-Australian genera, but I think that among the endemic genera, Menkea is perhaps closer to Stenopetalum than to any of those in the Arabidopsidineae (Shaw, 1965) or to those which have obcom- pressed siliques. Although Schulz, in 1933, transferred M. villosula to his newly described genus Phlegmatospermum, this was a result of his having relied on the original description of the species which contains some inaccuracies, and the two genera are, I think, not closely related; the three or four species of Phlegmatospermum all have strongly obcompressed, few-seeded siliques and are pubescent with malpighiaceous trichomes. All six species of Menkea are ephemerals of arid and semi-arid parts of central and southern Australia. Often they are found in A REVISION OF MENKEA 177 places such as creek beds and clay pans or in any shallow depres- sion which might receive runoff water. There are various notes on herbarium labels indicating that the plants were growing on soils derived from limestone and calciphily is not uncommon in the family. The center of distribution would seem to be in north- ern South Australia where five species have been found. The known range of each species is shown by the maps and the cited specimens; in each case the species may be more widely spread, but the plants are short-lived and, in part, grow in an area which is not well-known botanically. The genus is named for C. T. Menke (1791-1861), a physician and amateur malacologist of Bad Pyrmont. ACKNOWLEDGEMENTS I should like uh acknowledge the assistance of Dr. Hansjérg Eichler, Keeper of the State Herbarium of South Australia, si provide facilities and pe east i during the time I was a member of his staff, and the help and companionship of those people a Ah and collected wit in also wis nk Mr. A. C. Beauglehole of Gorae ustralia. z West, Victoria, Australia for permitting me ae: study m material from his rbarium, eth of the following eto: bt Paper Det inet mat — in their care: AD, ADW, B, BM, BRI, CANB ELU, NIE, E YD, W. The abbreviations are ae conducted by Lactenive and Seales (1964), with the exception of MELU, the herbarium of a Botany Department of the University of Melbourne, which is not listed n their publication. SYSTEMATIC TREATMENT Menkea Lehmann, Ind. Sem. Hort. Hamburg. 8. 1843 ate spEcies: Menkea australis Lehmann, Ind. Sem. Hort. Hamburg. 8. i Plants small glabrous or villous annuals; stems several, prostrate or erect m a rosette of basal leaves; basal leaves linear to oblanceolate, the blades entire, dentate or pinnatisect and narrowing to a slender petiole; cauline f stamens erect or spreadin ngs glandular tissue = cular to square or 178 ELIZABETH A. SHAW KEY TO THE SPECIES OF MENKEA A. Plants usually prostrate and spreading; siliques strongly compressed, the ti nearl ek ul siliques glabrou C. Petals usually white; tea completely reduced; ovules 40-80 per es ae OO 1. M.a molar ni BAe ly cnet a ana a ermer iis: Siete Wie 2 este om "Oana ries and siliques papillose and often twisted. .... Pay is ee A, Plan ts orn erect; siliques subt cece in section, the vas oe D. Plants villous with s arte HellOMmes: eso ks aes esl M. vi illosula. D. Plants completely glabro E. Pet ne white or cream- ed 2-3.7 mm. long; leaves subset and entire c E. Petals usually mauve or pink, 3-5.2 mm. bed — leaves not co spicuously succulent, usually lobed or dentate __ go | 1. Menkea australis Lehm., Ind. Sem. Hort. Hamburg. 8. 1843 Map 1 TYPE: Western Australia: without exact locality; Preiss 1937 (LU); probable isotype (MEL 7669). Sten opetalum procumbens Hook., Icon. PI. ot 610. 1844. HOLOTYPE: 3 Menkea procumbens (Hook. el . Muell., Frag, 2:142. 1861 Menkea coolgardiensis Sp. Moore , Journ. Bot. 35:162. 1897. HOLOTYPE: (i) Australia: near Coolgardie; Spencer Moore, 1895 (Bm); photo ae en | cm. istant, buds takes to ovoid; iepale 1-2 (25 ) o-1 i i 2.5 mm. long, 0.4-0.9 mm wide, white or pink to mauve, rather coarsely vei wk ieee or obovate or oblong, usually subacute, the margins entire o: e; stamens 2 mm. long, the filaments slender oak little expan anded; ale ~ a 28 sometimes alineotd, range-brown to dark red- L-brown —— as long as or slightly oe than the radicle. , ~ neseaT ECIMENS: South Australia. Evelyn Downs, Ising, 1952 AD OC tack Koch 326 (ap, BM, K, Nsw 77564); plane Gorge, A REVISION OF MENKEA 179 near Quorn, anon., 1916 (ap); Koonamore, Osborn, 1928 (syp); Wynarka, Ising, 1960 (ap); Whyalla-Kimba, Higginson, 1955 (ap); Ooldea, Cleland, 1935 (ap); Maralinga, Hill 749 (3m). New South Wales. Nyngan, Boorman, 1903 (GH, Nsw 77559); Cobar, Abrahams, 1911 (Nsw 77560); Broken Hill, Morris 393 (Nsw 77563); “Zara,” Wanganella via Hay, Officer, 1917 (ap); Murray and Darling River, Mueller ¢& Beckler s.n. (MEL 7665, MELU). Victoria. Swan Hill, McAdams 89 (met 11005); Hattah, Carr, 1955 (mELU); northwest of Lake Albacutya, French, 1887 (met 7664); Nhill, St. Eloy D’Alton 4 (mE. 7663). Western Australia. 4 miles south of Sand- stone, George 5 PERTH); near Laverton, George 3743 (PERTH); Northam, Fitzgerald, 1898 (Nsw 77565); Swan River, Drummond 2 series no. 48 (BM, K, LU, P, W). This species is probably more widely spread than the cited collections indicate, and might be looked for in the southern part of the Northern Territory and in southwestern Queensland. Al- though not uncommon, the plants are prostrate and short-lived and are easily overlooked by collectors. In habit, Menkea australis somewhat resembles Hymenolobus procumbens (L.) Nutt. ex Schinz & Thell., but the latter is distinguished by the siliques which are completely septate. In the protologue, Lehmann neither cited specimens nor men- tioned a locality but remarked “Semina in Australia occidentali ex herbario Preissiano accepimus.”, indicating that the descrip- tions are based on material collected in Western Australia by Ludwig Preiss during his stay there in 1838-1841. Bunge, who prepared the treatment of the Cruciferae for Plantae Preissianae, cited Preiss 1937 under Menkea australis, so it is likely that the material under that number in Lehmann’s own herbarium is the holotype. On Lehmann’s death in 1860, the Preiss collections in his herbarium were purchased by Agardh (Bot. Zeit. 20:255. 1862) and are still housed at Lund. Menkea coolgardiensis is known only from Spencer Moore's original collection. Mr. A. S. George, Australian Liaison Officer during 1968, kindly examined this specimen at the British Museum ( Natural History) and reported that, in his opinion, it is M. australis. Moore described his material as “sparsim puberula” and remarked that this species differed from M. australis “chiefly in the much larger flowers with their persistent reflexed sepals, as well as in the differently shaped silicules.” However, Mr. George found the plants to be quite glabrous; the size of the floral organs falls well within the range of those of M. australis; and the descriptions “siliculis oblongis compressis” and “Siliculae basi 180 ELIZABETH A, SHAW breviter angustatae, 0.4 cm. long., vix 0.2 cm. lat.” apply perfectly well to the siliques of M. australis. For several years Mueller confused Stenopetalum procumbens Hook. (Icon. Pl. t. 610. 1844) with S. draboides Hook. (Icon. Pl. t. 617. 1844), both names based on collections made in the Swan River Colony by James Drummond. Hooker apparently did not know of the descriptions of Menkea and M. australis published by Lehmann, and published S. procumbens before the second fascicle (pp. 161-320) of the first volume of Plantae Preissianae (in which Bunge gave amplified descriptions) appeared in De- cember, 1844 or January, 1845 (Stearn, Jour. Soc. Bibl. Nat. Hist. 1:203-205. 1939). In 1862, Mueller made the combination Menkea procumbens, based on Stenopetalum procumbens Hook.; on the same page he gave a brief description of M. australis, correctly citing Lehmann’s original description and the fuller one provided by Bunge, but he cited as a synonym S. draboides Hook., and remarked “Hujus speciei diagnosin juxta tabulam supra citatam [Icon. Pl. t. 617] exstruxi, quum plantam ipsam nondum viderim.” Having seen no authentic material of S. draboides, Mueller assumed it to be the same as Lehmann’s M. australis. It is surprising that he did not realize that Hooker's diagnosis and description of $. procumbens agree much better with the description given by Lehmann and Bunge of M. australis than do those of S. draboides. In particular, Hooker said of S. draboides, “. . . siliculis oblongo-obovatis compresso-planis subtortuosis unilocularibus (dissepimento nullo) minutissime puberuli-granulatis. . . .” The siliques of M. australis are never twisted and completely lack trichomes or papillae, while those of M. draboides are usually twisted and are always papillose. The taxonomy of these two species was clarified by Bentham (1863). The German-Australian collector, Max Koch, whose collections were widely distributed to Australian, European and American herbaria, in listing the plants he had found at Mt. Lyndhurst in the Flinders Ranges of South Australia (Trans. Roy. Soc. S. Austral, 22:102. 1898), said of Menkea australis, “My No. 326 is a variety differing from the typical form by the paucity of foliage. It is quite prostrate, racemes are filiform, flowers white, more minute than with M. australis, and the fruits somewhat narrower at the apex, and slightly wrinkled.” Koch here confused M. australis with a hitherto undescribed species. On one sheet of A REVISION OF MENKEA 181 Koch 326 (ap) he noted “prostrate var: very different from typical form 270.” However, the prostrate form (Koch 326) is true M. australis while Koch 270, also distributed as that species, is M. crassa E. Shaw, a species seldom found outside the Lake Eyre basin and the northern Flinders Ranges in South Australia. 2. Menkea lutea E. Shaw, sp. nov. Map 1 Herba annua Bae caulibus gracilibus plerumque prostratis; folia basalia rosulata, spatulata vel obovata, pleru me pinnatisecta lobis oque latere, in peti longiorem angustata; folia caulina remota, + obov ea in unguem aequilongum vel bre ttenu. a in beiailas alicees shadites vel ellipticae arting ephiottearin semina + ellipsoidea HOLOTY Western ere era. airstrip, bebe ahi Range per side, narrowi e; inflor but rapidly aint eter anthesis, bu is abnicbiae ome 1.7-2.3 mm. long, elliptic or oblong to ovate, some saitces cucullate; petals 1.8-2.8 mm. long, 0.8-1.2 mm. wide, bright yellow be coarsely veined, oblong to clongatedly obovate or sometimes with a distinct wale or rhombic lade essed, s nas or stipitate; styles — mm. long, stigmas small and depressed-capitate; septum reduced to a narrow rim, this present sometimes only at the proximal end of the aie Sele 0.7-0.9 mm. long, oblong to ellipsoid, orange to ipaitbayiatee cotyledons ae shorter than the radicle. ECIMENS SEEN: Western Australia. Wingellina near Mt. Hinchley, Cleland, 1960 sa) Blackstone Range Mining Camp, George 4820 (PERTH). npr airstrip by r road to Giles, Wilson 2466 fab): Western Australia or South Australia. Tompkinson Range, Cleland, 1954 (ap). The Tomkinson and Blackstone Ranges were crossed on horse- back by Emest Giles in 1873. Richard Helms, botanical collector with the Elder Exploring Expedition (which relied on camels for 182 ELIZABETH A, SHAW transport), spent several days in the western part of the Black- stone Range in 1891, but it is only in recent years, with the devel- opment of the weather station at Giles and the construction of airstrips, that this very remote area has been at all accessible to field biologists. Menkea sphaerocarpa and M. villosula have also been found in the ranges of northwestern South Australia, but both species differ from M. lutea in that the siliques are subglobose; further- more, M. sphaerocarpa has much larger mauve or pink petals and M. villosula is hirsute. 3. Menkea draboides (Hook.) Benth., Fl. Austral. 1:80. 1863 Map 2 Stenopetalum be cotyledons accumbent. 2n=36 SPECIMENS SEEN: occasion ial on inner slope, Outer Islet, Guadalupe Island, Baja California, Mexico, April 16, 1948, Reid Moran 2935 (ps); floor crater on Outer Islet, Guadalupe Island, July 18-19, 1937, Peter J. Roviet s.n. (ps). The Outer Islet is also known as Islote Zapato and according to Moran (1969) it consists mostly of a seabound volcanic crater with steep inner slopes and sheer outer seacliffs on three sides. 194 REED C. ROLLINS It is noteworthy that Moran found and described a new species of Eriogonum (E. zapatoense) from the same location. In its shrubby habit, Erysimum moranii is most like E. insulare and E. suffrutescens. However, it differs from each of these species in a number of significant ways, one of the most important being in the nature of the seeds. In E. moranii, the seeds are broad, flattened, winged all around and the cotyledons are accum- bent while in E. insulare they are narrow, plump, wingless and the cotyledons are incumbent. These two species also differ in the length of the pedicels and siliques, the pedicels being 1.5-2 cm. and the siliques 3-5 cm. in E. insulare compared to 3-5 mm. and 2.5-3.5 cm. in E. moranii. Actually, Erysimum moranii may be more closely related to E. suffrutescens, particularly var. grandifolium, than it is to E. insulare. However, these species differ considerably in growth habit, leaf disposition and leaf length. The pedicel length is some- what comparable, although usually shorter in E. moranii and the silique length of var. grandifolium is about the same or slightly longer than in E. moranii. The siliques of var. grandifolium are definitely tetragonal in cross section whereas they are broader and flat in E. moranii. The seeds of these taxa are radically different being plump, angular, wingless and with mostly incumbent cotyledons in var. grandifolium, but flat, nonangular, winged and with accumbent cotyledons in E. moranii. Furthermore, the trichomes of E. moranii are consistently two parted while being three parted in all infraspecific taxa of E. suffrutescens. Plants grown in a growth chamber from seeds of the type num- ber began branching after a few weeks of growth and continued to ramify into a bush-like form as growth proceeded. This growth habit is substantially different from that of many species of Erysimum (e.g., E. capitatum, E. asperum et al.) where a single rosette of leaves is most common and if branching does occur it is usually in the upper part of the flowering stalk. Actually, the growth-form is more like that of some of the Aegean species of Erysimum (cf., Snogerup, 1967a) which are also island dwellers. The chromosome number! of 2n—=36 in Erysimum moranii is the same as in a number of other North American species of the genus (Mulligan, 1966; Rollins, 1966). There are both large I am indebted to and wish to thank Mrs. Lily Riidenberg for this count and for the privilege of examining preparations of root-tip smears of E. moranii NOTES ON STREPTANTHUS AND ERYSIMUM 195 and very small chromosomes in the complement of this species and in this respect the cytological picture is similar to that of other American species as well. The range of chromosome size is far greater than in any complement of the Aegean species of Erysi- mum as given by Snogerup (1967b). LITERATURE CITED Muuucan, G. A. 1966. Chromosome numbers of the family Cruciferae. UI. anad. Journ. Bot. 44: 19. — = C. 1963. Protandry in two species of Streptanthus ( Cruciferae). gre :45-49. —_—_———— 66. Chromosome numbers of Cruciferae. Contrib. Gray Herb. 197: 1365, SNocERuP, S. 1967a. Studies in the Aegean ag Mag Erysimum sect. Chei- ranthus A. Taxonomy. Opera a Botanica No. 13:1-70. ——_—————. 1967b. Studies in the Aegean sate x. Erysimum sect. Chei- ranthus B. Variation and evolution in the small-population system. Opera Botanica No. 14:1-86. b iaibarege 5 ied a Ppa teas ie i INDEX 197 INDEX Actinophlebia 50 Alsophila 25 Amphicosmia 25 Amphidesmium 16 petroselinifolia 106 refracta 159 Schomburgkiana 112 villosa 91 Asplenopsis 84 ssa peo filipendulaefolium 54, Cnemidopteris 50 Cormophyllum 47 Craspedodictyum 56, 84 ryptogramma retrofracta 159 Cyathea 46 Cyatheaceae, Classification of 3 Dichorexia 25 accrescens 90, 144 aureonitens 90, 141 Biardii 166 cheilanthoides 61, 68 cheilanthoides x flexuosus var. flexuosus 136 cheilanthoides x Jamesonia 135 cheilanthoides x Jamesonia elongatus 135 flexuosus var. flexuosus pauci- folius 16 flexuosus var. flexuosus < Wars- cewiczii flexuosus var. galeanus 164 glaberrimus 68 16 glaberrimus X congestus 170 hirsutulus 71, 13 hirtus 104 hirtus var. glandulosus 108 hirtus var. glandulosus x flexu- osus var. flexuosus 1 hirtus var. hirtus 106 aie stibleks 128 Matthewsii 123 Monograph of the Fern Genus 54 myriophyllus 68, 91 novogranatensis 12 Orbignyanus 149 Ottonis 112 paucifolius 100 paucifolius var. neblinae 103 paucifolius var. paucifolius 102 paucifolius var. Steyermarkii 103 retrofractus 159 1 Sellowianus 94 198 setulosus 126 Stuebelii 145 velleus 116 Warscewiczii 68, 117 Eucheilantheae 55 5 car og 88 Fourniera 17 Glaus cheilanthoides 129 flexuosa hirta 106 a 54, 88 frons elongata 135 elongata var. brasiliensis 129 elongata var. itatiaiensis 134 extensa Sai Felip 1 flipendolafoia 129 flabellat Socom on flexuosus var. linearis 159 eager var. glandulosa 172 106 ei pes 116 hispidula 112 incisa 114 INDEX insignis 152 longipetiolata 128 Mathewsii 122 Mathewsii var. glabriscula 172 niece nae myriophylla enh var. gia hatin 91 myriophylla var. eglandulosa f. flexuosa Orbignyana 149 Ottonis nega paucifolia Potroselinifala 106 Regnelliana 172 retrofracta 159 rufescens 122 Ruiziana _ scandens 1 casas 112 Schwackeana 94 7 agree spe 59, 115 135 Alston iscceiaaia 68, 139 brasiliensis 135 canescens 14 cinnamomea 127, 128, 166 Goudotii 127, 128, 135 hispidula 112 imbricata var. glutinosa 139 australis 177, 178 coolgardiensis 178 crassa 18 draboides 182 e rocumbens 178 Revision of aa Genus 175 sphaerocarpa villosula sg Metaxya 16 Microstegnus 50 Nephelea 37 Neurogramma scandens 152 Phlegmatospermum villosulum 183 5 Polypodium astrolepis 135 Psilogramme 55, 88 aureonitens 141 asana 108 cheilanthoides 129 elongata 135 INDEX 199 flabellata 136 flexuosa 159 glaberrima 169 glandulosa 108 haematodes 159 mbes 137 hirta hispidula lig myriophylla 91 Orbignyana 149 Ottonis 112 paucifolius 102 portoricensis 112 refracta 159 rufescens 123 sennodalahen 112 Schizocaena 16 Shaw, scm ACTS Shpaeropteris 1 Stenopetalum draboides 182 procumbens lj spake Notes on 190 Tryon, Alice 54 Tryon, Rolla 3 Contributions from the GRAY HERBARIUM 1971 NO. 201 ‘ Reed C. PROTOGYNY IN THE CRUCIFERAE Rollins AND NOTES ON ARABIS AND CAULANTHUS THE VASCULAR FLORA OF ST. LAWRENCE ISLAND WITH SPECIAL REFERENCE TO FLORISTIC ZONATION IN THE ARCTIC REGIONS Steven B. Young Reed C. Rollins CHROMOSOME NUMBERS OF and CRUCIFERAE II Lily Rudenberg . EDITED BY Reed C., Rollins . Kathryn Roby PUBLISHED BY THE GRAY HERBARIUM OF HARVARD UNIVERSITY IssuED JANUARY 95, 1971 Contributions from the GRAY HERBARIUM 1971 yon Reed C. Rollins Steven B. Young y ; on : \ eed ° — CHROMOSOME NUMBER ig g i CRUCIFERAE UL S04 A Lily Riidenberg SSRN i, EDITED BY Reed C. Rollins Kathryn Roby es ae ied PROTOGYNY IN THE CRUCIFERAE AND NOTES ON ARABIS AND CAULANTHUS REED C. ROLLINS Since my early works on Arabis (Rollins 1936, 1941), I have grown many species of the genus and studied more than a score of North American species in flower in the greenhouse or experimental garden. However, none of these showed any evidence of functional protogyny and none had excerted anthers. Now, flowering material of the taxon I have previously called Arabis suffrutescens var. perstylosa shows both pro- togyny and excerted anthers to be present. When buds are fully grown and just before anthesis, the elongating style projects through the apex of the slightly opened bud exposing the stigma. This is clearly shown in the left hand photograph of Plate 1. After pollination, the style tends to bend to one side of the flower and the filaments elongate until the anthers of the paired stamens are well excerted above the corolla. Even the anthers of the shorter single stamens are above the ends of the petals when the flower is at full anthesis. The anther position is shown in the right hand photograph of Plate 1. Tests on three plants show them to be self-incom- patible. This is taken as reasonably good evidence that the taxon as a whole is essentially self-incompatible. Protogyny is not supposed to be present in the Cruciferae (Bateman 1955a) and even now we assume it is not common in this family or its occurrence would have been noted in the literature. Such a modification of the usual maturation sequence within the flower promotes outcrossing and is of significance for the survival of a population if there is a reduce gene pool and if other outcrossing mechanisms are not present or are ineffective by themselves. The Arabis population from which our seeds were obtained apparently is a small localized one and there is some circumstantial evidence that this taxon itself is very restricted in numbers of populations, possibly con- sisting of a single population of a limited number of individuals. Only two collections of it have been made, both by Professor Lincoln Constance of the University of California at Berkeley. He made the first collection, in 1938, which was used as the basis for describing the new taxon, A. suffrutescens var. perstylosa. In 1969, Dr. Constance, accompanied by T. I. Chuang, made a second collection at the same site as the first, including mature seeds from which our plants were grown. At that time a considerable search of the area was made without the discovery of any new sites. The one known population is on an open serpentine outcrop near rocks. Other crucifers, particularly taxa of the genus Streptanthus, occupy similar serpentine habitats (Kruckeberg 1951, 1954, 1957) and are often equally limited in their distributions. In the case of the Arabis here being con- 4 REED C., ROLLINS : ax th PLATE 1. Arabis constancei. Left, bud with projecting style. Right, flower at full anthesis. Bo figures 20. Photo by Frank White. PROTOGENY IN THE CRUCIFERAE 5 sidered, it is possible that the population has become too reduced in incompatibility allele number for self-incompatibility to function efficiently as an outcrossing mechanism. Selective pressure to promote outcrossing in some other way could be intense under such circumstances. The de- velopment of protogyny is one way the need for increased outcrossing could be insured by the population, if the incompatibility system became inefficient. It is interesting that new information has now completely negated the statement Bateman (op. cit., p. 63) could make only a few years ago that, “there is no protandry, no protogyny and no dioecy in Crucifers.” We have shown that protandry is present in two species of Streptanthus (Rollins 1963), dioecy was acknowledged to be character- istic of Lepidium sisymbrioides by Bateman (1955b), and now, protogyny is shown to be present in the family. There is evidence produced by one of my students, Mr. Ihsan Al-Shehbaz, that protogyny occurs in the genus Thelypodium and we now think it may be more widespread in the Cruci- ferae than we would have supposed at the time of our initial discovery f it.t In the course of our study of the Arabis material referred to above, it has become clear that the taxon involved should be recognized on the specific level and not associated with A. suffrutescens as in my former treatment. Because of his involvement in obtaining the original, and sub- sequent collections, and his continued interest and help, I propose to name this species for my former mentor and long time friend, Dr. Lincoln Constance. Actually Dr. Constance and I published a new species of Arabis together [A. crucisetosa] many years ago (Constance & Rollins 1936). Arabis constancei Rollins, sp. nov. erba perennis, ue ramosis, caulibus simplicibus erectis glabris 1.5-3 dm. Gia. foliis basilaribus tegris glabris vel ciliolatis lineari-oblanceolatis 1.5-3 cm. longis, mm. latis, foliis evalinds sessilibus non auriculatis glabris, sepalis glabris eg mm. longis, siliquis compressis glabris pendulis acutis vel accuminatis 4—5.5 cm . longis, 3-4 mm. _latis, stylis 2.5-4.5 mm ear an — orbicularibus vel late ellipticis in the e Gray Herbarium, cpliectod near sone on open serpentine, ‘ 6 miles southeast of "ulaey on road to Blairsden, Plumas Co., California, July “¢ _ LL. Constance & T. I. Chuang 3875. era aaipcion "studied: open bar pease ne slope, above Middle Fork of the Feather River, 7.3 miles southeast of Ounicy. Plumas ae “biases re June 9, 1938, L. Constance 2309 (GH). nial; stems one to several from a branching subligneous caudex, erect, simple, le apie dan 1.5-3 dm. high; basal leaves in dense rosettes, entire, linear- Gh laxsclste, acute, stiff, thickish, with a prominent mid-rib, bluish-green, ciliolate 1While the present paper was in process, an unpublished thesis entitled, HL einicneore in the Floral Biology of the Arabis Holboellii Complex,”’ by Thomas Frank Johnson sent e by Professor par R. Kruckeberg. Johnson observed emergent pistils in Arabis holboellii ar nA. "Stee which surely means that they are protogynous. Thus, we are certain of the Peditio at protogyny is more common than we could have reasonably believed a few months 6 REED C. ROLLINS on the margins with simple or forked trichomes to glabrous, 1.5-3 cm. long, 2-3.5 mm. wide; cauline leaves entire, oblong to lanceolate, sessile, non-auriculate, glabrous, reduced upward, overlapping below, remote above, 1-1.5 cm. long, 2-4 mm. wide; mm. long, filaments of single stamens 6-7 mm. long, anthers ca. 1 mm. long; siliques pendulous to strictly reflexed, glabrous, strongly flattened, nearly straight but with uneven margins, nerved from base to middle or slightly above i apex, 4-5.5 cm. long, 3-4 mm. wide; styles 2.5-4.5 mm. long; fruiting pedicels strongly reflexed but not geniculate, glabrous, 6-10 mm. long; seeds flattened, nearly orbicular to slightly oblong, winged except for area of funicular attachment, ca. 3 mm. in diameter including wings; wing ca. 0.5 mm. wide; cotyledons accumbent; radicle separated from cotyledons by a deep groove. 2n = 14. There is no doubt that Arabis constancei is a close relative of A. suffrutescens, However, the exposed differences betwen these taxa have been increased in number as we have had more material to work with, particularly growing plants, from which we could make comparisons of characters. The sharpest differences are in the flowers which we did not have available for study at the time of our former treatment of this taxon. Previously, we had indicated the plants of Arabis constancei to be wholly glabrous. But the new specimens of this species show the basal leaves frequently to be ciliolate-margined. If the leaves become glabrate, ere often is one or a few trichomes at the apex of the leaf. For some reason, the specimens of the earlier collection, Constance 2309, were wholly glabrous. This is also true of the plants we grew in the greenhouse even though the seeds were from wild plants which had at least some trichomes on their basal leaves. Arabis constancei differs from A. suffrutescens in having non-auriculate instead of auriculate cauline leaves, greatly elongated styles instead of sessile stigmas or at most very short styles, excerted stamens rather than included stamens and seeds with wings about 0.5 mm. wide rather than 1 mm. wide. In general, there is less of a woody foot present in A. con- stancei than in A. suffrutescens. Also, there is a much better developed basal rosette with a denser cluster of leaves in the former than in the latter. In any given plant of A. constancei usually there are both fertile branches and sterile branches present. But in A. suffrutescens, sterile branches are not present or are exceedingly rare. CAULANTHUS At various times over the past thirty years, I have considered the generic problem posed by a strong similarity of several species, some of which are usually treated in the genus Streptanthus and others that are ordinarily placed in Caulanthus. Might not all these species be better put under Streptanthus, the older of the two names, as was done by Jepson (1936)? In setting up the genus Caulanthus, Watson (1871) was impressed by the PROTOGENY IN THE CRUCIFERAE Z need to separate from Streptanthus a group of species having seeds with incumbent cotyledons, mostly terete to slightly obcompressed siliques and petals with reduced blades. He left to Streptanthus those species with siliques strongly flattened parallel to the septum, seeds with accumbent cotyledons and petals with developed blades. Greene (1904) strongly dissented from the treatment of Watson and a later one of Robinson (1895), but by proposing nine new genera to include the species mostly to be associated together in Streptanthus and Caulanthus, he was hardly of any help in developing a reasonable classification for the group. Payson (1923) provided an important presentation of the problem and of a classi- fication that was more or less in accord with the treatment of the earliest authors. His monograph has helped to establish Caulanthus in the manuals and floras and I believe this is nearer the mark than would be a return to a more inclusive Streptanthus. However, we are quite aware that Strep- tanthus and Caulanthus illustrate once again one of the most frequently encountered problems in the taxonomy of the family Cruciferae, that of indistinct boundaries separating the genera. In my judgment, it is in the interest of a reasonable and workable classification to accept both Caulanthus and Streptanthus. It was necessary to review this matter and arrive at a decision in order to be able to handle the identities of certain specimens received from several areas in the intermountain basin. For the present, I shall deal with one new taxon that falls clearly into the genus Caulanthus. However, since Jones (1893) referred to specimens of it in the protologue of the original description of Thelypodium elegans, it is first necessary to point out that although the species described below resembles T. elegans [Sisymbrium elegans (Jones) Payson] in a general way, the two taxa are very distinct. I have examined the holotype and three isotypes of T. elegans. These are Consistent with the description insofar as the characters of the plants are concerned and differ only with respect to the minor fact that the labels all read May 6, 1891 instead of May 7, 1891 as given in the protologue. At- tached to the holotype is a card giving the description in Jones’ hand- writing, largely as he published it. However, two collections with the same data as the type series, “Westwater, Colo., May 6, 1891, collected by Marcus E. Jones, A.M.,” one at California Academy of Sciences and one at the Gray Herbarium, are similar to specimens from Green River, Utah, referred to below and do not belong to the type series. It is assumed that there was some mixing of two collections before they were distributed, perhaps by Jones himself. In the protologue, Jones states “A form from Green River, Utah, that I refer to this species is simple stemmed and with appressed pods.” Two collections from the Jones herbarium in the Pomona College herbarium dated May 7, 1891 and May 9, 1890 from Green River, Utah, undoubtedly represent the material mentioned. These and several More recent collections from the Green River area belong to Caulanthus divaricatus rather than to Sisymbrium elegans. 8 REED C. ROLLINS Caulanthus divaricatus Rollins, sp. nov. pedicellis divaricatis tenuibus glabris vel sparse pubescentibus 7-12 mm. longis, siliquis teretibus divaricatis glabris vel sparse pubescentibus 6-9 cm. longis, 1.5-2 mm. longis, seminibus oblongis immarginatis 1.5-2 mm. longis, cotyledonibus incumbentibus. Holotype in the Gray Herbarium collected about 75 miles west of Blanding and 10 miles east of Hite, Twp. 34 S. R. 14 E., San Juan Co., Utah, May 16, 1961, Arthur Plants annual, single stemmed and without a true basal rosette of leaves; stems erect, virgately branched above, rarely simple, densely pubescent below with contorted and twisted whitish flat trichomes to nearly glabrous, usually glabrous above, 2-9 dm. high; lowest cauline leaves densely overlapping, sessile but scarcely auriculate, entire to irregularly dentate, oblong, obtuse, strongly 1-nerved, sparsely pubescent to m. long, 1-3 cm. wide; cauline leaves becoming strongly auriculate in shape and more acute than the lower; all branches terminated by dense inflorescences; flower pedicels divaricately ascending, slender, sparsely pubescent to glabrous; sie mm nerved, 7— long; claw whitish, obovate, abrupty narrowed at bl junction, mm. long, ca. 2 mm. wide; blade vertically folded and crisped, yellowish, mm. long, ca. 1 mm e; filaments erect, 44.5 mm. long; anthers slightly excerted, sagittate, introrse, not coiled, ca. 1.5 mm. long; paired stamens only slightly longer than single stamens; mold of glandular tissue subtending base o nearly encircling single filaments except for an area below filament insertion; ovary terete, usually very sparsely pubescent; stigma slightly larger in diameter than s le, slightly bilobed, the lobes over the r iting pedicels divaricately There is some variation represented by the specimens cited below but most of this appears to be uncorrelated. The differences such as glabrous vs. pubescent individuals are present in the same populations as are differences in the length of the gynophore. The position of the pedicels and of the siliques appears to be related to maturity. Both pedicels and siliques are nearly erect in the earlier stages becoming more widely spreading as the infructescences mature. Caulanthus divaricatus has flowers that are yellowish in overall appear- ance because the sepals, short petal blades and anthers are yellow to straw colored. However, the claw of the petal which is included within the calyx is much lighter and in living material we have in the greenhouse this part of the petal is nearly white. In dried specimens, the same appears to be true. The broad claw which abruptly narrows to a constriction at the junc- tion of the crisped blade is a feature of most species of Caulanthus and PROTOGENY IN THE CRUCIFERAE 3. Photo by Frank White. e, X 2/ of the holotyp 10 REED C. ROLLINS serves to distinguish this species from others in Sisymbrium with which it might otherwise be confused. OTHER COLLECTIONS STUDIED, Utah Carbon Co.: 2 miles n. of Price, D. E. Bright 10 (Bru); Price, S. Flowers 1438, 1438a (ur). Emery Co.: 1 mile n. of Castle Dale, Bassett Maguire 18334 (Ny); about 10 miles east of pone pa Higgins & Reveal 1256 (cu, “ae Clawson, Ripley & Barneby 4735 (cas, cH); 3 miles n. of Woodside, S. L. Welsh 6887 (nyu, ny); Gunnison Butte, O. S. Walsh 31 Sad 1 mi. s. of jet. 6, 1891, M. E. Jon (cas, cH); Grand River near Moab, vous 3, 1915, E Jones s. n. (GH); Cisco, May 6, 1891, M. E. Jones (uc); Green River, May 7, 1891, E. Jones s.n. ( same, May 9, 1890 (Pom, uc); same, May 1914 (cas, (cu, Ny). Garfiel pe sheet 25 miles s. of eo Welsh, Atwood & Higgins 8953 (syu). San Juan Co.: Whirlwind Draw, R. 15 E., T. 39 S., H. Rooney 245 (yu). 2Not “Colo” meaning the state of Colorado as would be assumed from the way the label is written and as was given by Jones in his citation of the type of Thelypodium elegans. A clue to this mistake is found in Jones’ handwritten note on one of the sheets in which he says, ““Westwater on the Colo., meaning the Colorado River. Westwater is in Utah, although it is near the Colorado border. LITERATURE CITED BATEMAN, A. : 1955a. Self-incompatibility Systems in Angiosperms III. Cruciferae. Heredity 9: 53-68. ———————. 1955b. Note on Dioecy in the Cruciferae. Heredity 9: 415. Constance, L. anp R. C. Rotuins. 1936. New or otherwise Noteworthy Northwestern Plants II. Two ote Species from the Grand Canyon of the Snake River. Proc. Biol. Soc. Wash. 49: 147-150. GREENE, E. L. 1904. Sake West American Cruciferae. Leaflets Bot. Obs. and Crit. 1: 81-90; cf., 224-299. JEpson, W. L, 1936. A Flora of California I: 20-35. Jones, M. E. 1893. Contributions to Western Botany. No. 5. Zoe IV: 254-282. Kruckeserc, A. R. 1951. Intraspecific Variability in the — of Certain Native Plant Species to Serpentine Soil. Amer. Jo ——-————. 1954. The Ecology of se ian Soils. IL Pad Species in Relation to Serpentine Soils. Ecology 35: 2 ————-—— - 195 57. Variation in F ser ty e Hybrids between Isolated Populations of the tine Species, Pci peat glandulosus Hook. Evolution XI: 185-211. . nographic Study of Thelepsodabe and Its Immediate Allies. n. Mo. Bot Catt 9: 233-324 iain: B. L. 1895. Cruciferae. Gray and Watson, Synoptical Flora of North America t pt. I. agiroe Rouuins, R. C. 1936. bags Genus Arabis L. in the Pacific Northwest. Res. Studies State Coll. Wash. IV: 1-52. een, SORE A Mobigaries Study of Arabis in Western North America. Rhodora 43: 289-325, 348-411, 425-485, : rie ip tandry in Two Species of Streptanthus (Cruciferae). Rhodora Serpen oe | Dey 3 eal | 65: Watson, S. ey Botany. U.S. Geol. Expl. Fortieth Parallel V: 14-31. THE VASCULAR FLORA OF SAINT LAWRENCE ISLAND, WITH SPECIAL REFERENCE TO FLORISTIC ZONATION IN THE ARCTIC REGIONS STEVEN B. Younc! INTRODUCTION This paper consists of two sections: the first, a discussion of the vascular flora of St. Lawrence Island; and the second, a theoretical scheme for breaking the arctic regions of the world into a series of four floristic zones. This proposed system is an outgrowth of my fieldwork on St. Lawrence during the summers of 1966 and 1967, which also resulted in the treatment of the island’s flora given in Section 1. When I first became interested in St. Lawrence Island, I was struck by the fact that less than 200 species of vascular plants were known to occur there, although some 500 or more species were known from areas on the adjacent mainland of Alaska. Since the Quaternary history of St. Lawrence is similar to that of the adjacent mainland areas, I assumed that the paucity of species reported from the island was simply the result of insufficient fieldwork. I fully expected to add 100 or more species to its known flora, particularly since many of the species that I expected to be the most common had never been collected ere. ; During my first summer's work on St. Lawrence, it soon became evident that the island’s flora was, in fact, much more depauperate than that of any area of similar size on the adjacent mainland coast of Alaska. I was also surprised to discover that many species which were most abundant on the mainland coast were either missing entirely from the St. Lawrence Island flora, or were found only in a few isolated stations, usually in protected areas on the south side of the island. Clearly, the depauperate- ness of this flora must be largely due to currently acting ecological, rather than historical, factors. In this paper, it is shown that the main ecological factor is the amount of warmth available during the growing season. The majority of arctic vascular plant species have a northern limit of distribu- tion which is in a state of equilibrium, controlled by the summer tempera- ture regime of the area. On the basis of climatic data, it is possible to make quite accurate predictions of the composition of the flora of an area. Conversely, floristic data can be used to indicate the probable summer climatic regime of an area. A number of anomalous situations, such as the unusually rich flora of the Inner Fjord Region of Spitzbergen, can be explained on the basis of the concepts discussed in Section 2 of this paper. 1Present address: Academic Faculty of Botany, Ohio State University, Columbus Ohio. Research supported by National Science Foundation Grant GB7346 to Harvard University (Re c Rollins, Principal Investigator), the Fernald Fund of Harvard University and the Society of Sigma Xi. 12 STEVEN B. YOUNG ACKNOWLEDGMENTS Much of this paper is based on a Ph.D. dissertation of the same title which was prepared under the guidance of Professor Reed C. Rollins, Director of the Gray Herbarium. Professor Rollins help, advice and encouragement are gratefully ac- versity Herbaria. It has been a pleasure and a privilege to work in an atmosphere where helpfulness and friendliness are combined with such a high level of wes age ors thank Mr. Slwooko, his family, and the people of the villages of Gambell and Savoonga for helping to make my two summers on the island the source of a great deal of r. " Aq as. Department of Fish and Game at Nome, has always given freely both of his hospitality and of his store of knowledge of the Bering Sea region. SECTION 1. THE VASCULAR FLORA OF SAINT LAWRENCE ISLAND LocaTION AND HIsToryY Saint Lawrence Island lies in the northern portion of the Bering Sea, about 150 miles due south of the Bering Strait. Its location, in relation to adjacent mainland areas, can be seen on the map (Fig. 1). Although politically part of the State of Alaska, the island is geographically more closely related to Asia. On a clear day the jagged mountain ranges of the Chukchi Peninsula are clearly visible from the northwestern headlands of St. Lawrence as the Anadyr Strait, which separates the island from Cape Chaplino on the Siberian mainland, is less than 40 miles wide. One hundred and thirty miles of open sea separate St. Lawrence from the Alaskan mainland, which cannot be seen from the island under normal conditions of visibility. The Siberian affinities of St. Lawrence are nowhere more evident than with respect to the native human population of the island. Their Eskimo language is a branch of the Yupik dialect which is spoken only by the islanders and the natives of the adjacent coast of Siberia. In many other aspects of culture and physique, the St. Lawrence islanders show that their contact with other peoples has long been by way of Siberia (Giddings 1967). Saint Lawrence Island lies some 200 miles south of the Arctic circle, at about the same latitude as Trondheim, Norway. Nevertheless, the environ- ment of the island is truly arctic in every sense of the word. Low-lying areas are covered with dun-colored sedge tundra, while the hills are mostly barren rock and fell-field. The shrubby species which are so typical of the lush tundra of the Bering Sea coast of the Alaskan mainland occur only rarely on St. Lawrence, and the general aspect of the island is ex- tremely bleak and barren. From November to June the island is locked in the grip of the polar ice pack, and dense fogs and high winds are of com- a a ~ ~ ~ VASCULAR FLORA OF ST. LAWRENCE ISLAND ~ _— ee ~ Wrangel | ~ ~_~—_— . Re, Saint \ Lawrence ‘\ I. ae a eae Ebi ‘ 1 \ BERING SEA Sin Sor eee -~ -— ‘ “ ~ ‘ / / ‘ ‘ j \ \ 4 \ f 1 : \ ! a 50m 100m x ae . \ b. ’ ~ ty me / ws ¢ be a ‘ ~ me = \ Wi : \ 1 tp i \ Pribilov _ Is. L-7, me fnace a ai / ne a’ Pas ee Se i ee ae oe 1c. 1. Map of the epg eect Sea region. Approximate locations of 50 a shown by dotted lines. Durin s of maxim Bridge were in the vicinity of the ainsi 100 m isoba' um glaciation, bath. nd 100 m iso the shores of the Bering baths Land 14 STEVEN B. YOUNG mon occurrence throughout the year. Weather records indicate that the temperature regime of St. Lawrence is similar to that of Barentsburg, Spitzbergen, and Upernavik, at 75° north in high arctic West Greenland. In sharp contrast to the barrenness of the land of St. Lawrence is the richness of the surrounding seas. Even today, after decades of overhunting, walrus, seal and whale are abundant during much of the year. The sea cliffs of the island support dense colonies of breeding sea birds which live on fish and crustaceans from the sea. The richness of the Bering Sea has allowed St. Lawrence Island to support a comparatively large human population for long periods of time, probably several thousand years. One can hardly travel a mile along the coast without seeing the remains of human habitations. There are several ancient village sites of magnificent proportions. The most impressive ones are built on a mound of their own rubbish rising to a height of 20 to 30 feet, and covering an area of several acres. The skulls of several hundred large whales can be seen on the surface of the abandoned village of Kialegak, and it is impossible to estimate the number of whales and walruses whose bones are buried in the huge mound. Instead of living the marginal, half-starved existence which many people believe to be the lot of the Eskimo, the inhabitants of Kialegak must have luxuriated in an abundant supply of fresh meat. An advantage of living in a cold climate is that meat can be kept relatively fresh in underground storage chambers for long periods of time. During the long nights, when a winter’s supply of whale and walrus meat filled the meat cellars, the ancient islanders must have had plenty of time to dance to the monotone beat of the walrus-gut drums and to develop their art of carving the refractory walrus ivory. Apparently the first European to learn of the existence of St. Lawrence Island was Vitis Bering, who sighted the island on August 10, (O.S.) 1728. Bering did not land; however, he did note the presence of “cottages of fishermen.” He also gave the island its name, in honor of Saint Lawrence, on whose day the island was discovered. Many of the other early voyagers to Alaska came by way of the Bering Sea, and several of them made land- falls on the island. However, it did not prove to be a good source of valuable furs or precious metals, and was left more or less alone until the latter part of the 19th century, when the New England whalers began to hunt intensively in the Bering Sea. The islanders, well trained in the art of whaling, were soon being recruited as crew members. They also had large quantities of baleen and arctic fox furs for trade, and in later years some of the Eskimos became quite rich, even by white men’s standards, prompt- ing the disapproval of the resident missionaries. However, the first prolonged contact between the white man and the St. Lawrence islanders was disastrous for the latter. The whalers’ trade goods consisted largely of alcoholic beverages, and during the late 1870's the native population, weakened by excessive drinking, low on food, and probably suffering from an epidemic of some exotic disease, was dev- VASCULAR FLORA OF ST. LAWRENCE ISLAND 15 estated. Villages which had been in existence for hundreds of years were so completely depopulated that the corpses were left unburied. At Kialegak it is still possible to find in the short, stiff tundra sedge which covers the village site, human skeletons lying where the bodies fell. By the time the naturalist, John Muir, arrived on the island aboard the Corwin in 1881, there were only about two hundred islanders left out of a population which may have been as high as 2000. The only village that survived with even a fraction of its population was Sevuokuk (Gambell) at Northwest Cape. The white man came to St. Lawrence to stay about 1900, with the arrival of missionaries and schoolteachers at Gambell. At about the same time, reindeer were introduced to the island from Siberia. The best reindeer grazing lands proved to be the barren volcanic uplands of the Kookooligit Range in the central portion of the island, which supported a fairly heavy growth of the lichens that reindeer feed upon. To take advantage of the good grazing, the new village of Savoonga was founded on the north shore of the island, a short distance from the abandoned village of Kookoolik. Gambell and Savoonga are the only real villages on the island at present. Anthropologists have long believed that the pre-Columbian inhabitants of North America reached the continent by way of the Bering Strait. Be- cause St. Lawrence Island is so strategically located with respect to studies of the migration of early man across the Bering Land Bridge, the island has drawn a good deal of interest in archaeological circles, and excavations on the island began as early as 1930. Since then, extensive excavations at Gambell and Kookoolik have been made. There is no evidence at present regarding the existence of land bridge man, but numerous important discoveries of ancient Eskimo cultures have been made. Some of the carved ivory objects found on St. Lawrence represent the apex of Eskimo artistry and craftmanship (cf., Ray 1961; Giddings 1967). With the onset of World War II and the Japanese occupation of the western Aleutian Islands, the military arrived on St. Lawrence, although never in great numbers. A number of small military installations, such as radar sites, were set up but most of these have subsequently been abandoned. A United States Air Force base at Northeast Cape is still in operation. The native population of St. Lawrence Island is now about 1000 people, most of whom live in the villages of Gambell and Savoonga, although a small number also live near the Air Force base at Northeast Cape. Saint Lawrence is still one of the most isolated parts of Alaska, and the islanders have retained more of their traditional culture than have most Alaskan Eskimos. Much of the livelihood of the people is still based on the hunting of seal and walrus in the surrounding seas. The old houses of sod, driftwood and walrus hide have given way to small frame houses, many of which are a curious mixture of native and “white man” 16 STEVEN B. YOUNG architectural styles. The seal oil lamp has been replaced by gasoline and oil stoves, and the walrus skin boats are often powered by outboard motors, but the basic pattern of life on the island has been relatively stable until the present. In general, the St. Lawrence islanders make relatively little use of the native plants of the island. A few species such as Sedum rosea are collected for food, while some others, notably Angelica lucida, are thought to have medicinal properties. The ethnobotany of the island is treated in detail in a separate paper (Young & Hall 1969). PHYSIOGRAPHY AND GEOGRAPHY Saint Lawrence Island is about 100 miles long and varies in width from 10 to 40 miles. The total area of the island is roughly 2000 square miles, approximately equal to that of the State of Delaware. The eastern end of the island is a low, level plain punctuated by several ranges of block mountains, so that from the sea one has the impression of several separate islands, The western half of the island consists mainly of mountains and raised plateaus, with areas of low-lying plain being found only in a relatively narrow strip along the north coast, and along the north shore of the Koozaata Lagoon. The locations of the various physiographic features of the island are shown in Fig. 2. The total length of the coastline of St. Lawrence is about 350 miles. About half of it consists of sandy barrier beaches which separate lagoons from the ocean; these beaches are normally from 100 yards to half a mile wide, and they seldom rise more than 20 feet above high tide line. The lagoons, enclosed by the barrier beaches, are often of considerable size. Koozaata Lagoon, the largest, is about 40 miles long and two to three miles wide. Most lagoons have a single outlet which normally discharges fresh water into the ocean, but during storms and periods of unusually high tide, salt water may back up into them or even wash over the barrier beaches. In areas where the coastline is low-lying and lagoons do not occur, the coast consists of rocky capes and points separated by narrow stretches of sand and pebble beach. Here tundra and fell-field often reach to the edge of the sea. About 75 miles of the island’s coastline consists of sea cliffs. The two major cliff areas are along the north shore of the island between Kangee and Cape Kitnik, and along the southwest coast from Booshu Camp to Powooiluk. The north shore cliffs seldom rise to more than 200 feet; they are formed by the action of the sea on stratified beds of soft volcanic rock. These cliffs often rise nearly vertically or are even sharply undercut, and may extend for several miles as an unbroken barrier. Erosion is rapid and great chunks of rock fall from the cliff faces during the spring thaw or after heavy rainstorms. As perilous as they may be, their rocky ledges provide nesting sites for hundred of thousands of sea birds. An isolated VASCULAR FLORA OF ST, LAWRENCE ISLAND 17 fookoolik BERING Séq ue! . gtolbi Rocks 10 mi. x So etctcetetatatstretots . setae So eoegeee Ataakas ComP es * SOO a pore” at, ons ° SSNS SSS pascesentce SOS Bice. Gaedtuk pox * Booshu Camp , NORTHEAST CAPE Boxer BOY eetatets SO x » SESS Mountains gS Punuk Is. Fic, 2. Map of St. Lawrence Island. Dots show locations where intensive collections were made by author. Open circles show areas visited and where some specimens were collected. Since many of the collections were made between points, not all collection locations are shown. section of these cliffs form Stolbi Rocks, a group of vertical stacks which rise from the sea about three miles offshore from Cape Kitnik. Their sides are a sheer rise to a height of perhaps 250 feet. The thousands of breeding birds on this inaccessible islet effectively eliminate any vegeta- tion of vascular plants. The granite cliffs along the southwest coast of the island are of an entirely different aspect. The cliff faces are usually broken by cirques and talus slopes, so that unbroken sheer cliff faces stretching more than a ile or so are rare. In some cases the cliffs may rise to a height of 1000 feet. With their turreted peaks and castellated monoliths of gray granite, they remind one of a monstrous ruined city. This little visited area un- doubtedly has the most spectacular scenery on St. Lawrence Island. While true sea cliffs are not found in areas other than the two mentioned above, steep talus slopes reach the coast at Gambell, Tapphook, and Southeast Cape. Approximately one-half of the land area of St. Lawrence consists of lowlands with an elevation of less than 100 feet above sea level, a con- siderable fraction of which is covered by shallow lakes and ponds ranging in size from a few yards to a mile or more in diameter. These ponds are usually shallow, with low banks and ephemeral inlets and outlets. The surrounding tundra is poorly drained and often saturated with water, or even covered with standing water thoughout the growing season. There are several rivers of considerable size on the island. The lower reaches of the rivers are broad and sluggish, with winding channels and many cutoff lakes. This is particularly true of the Koozaata River in the south-central portion of the island. Some 15 species of plants, otherwise unknown on St. Lawrence, grow in and around this river. Many rivers 18 STEVEN B. YOUNG are navigable by skin boat for comparatively long distances, and it would probably be possible to cross the eastern end of the island by boat with only a few short portages. Other rivers are swift and clear, and often con- tain well-developed gravel bars, where many unusual species are found. The mountains of the eastern and western ends of the island appear to be uplift mountains, and the exposed rock is mostly granitic. The entire southwestern portion of the island consists of a dissected upland about 200 square miles in area and reaching elevations of 1500 feet. The tops of the mountains are broad, rolling, rock deserts, which often drop away sharply to valley floors and to the sea. This area is the only part of St. Lawrence which shows evidence of having been glaciated at some earlier time. There are several spectacular cirques and some broad U- shaped valleys. The valley glaciers probably never coalesced to the point of forming even a local ice cap. Large patches of firn are found at several locations, and a relatively minor change in the climatic regime of the island could result in the formation of small glaciers within a relatively short period of time. The mountains of southwestern St. Lawrence extend to the north and east as rolling, rocky plateaus, usually with an altitude of less than 500 feet. The northward extension culminates at Sevuokuk Mountain on Northwest Cape, while the eastward extension ultimately disappears under the lava flows of the Kookooligit Range. A mountainous spur to the northeast reaches the coast at Tapphook. Perhaps the most salient geographical feature of St. Lawrence is the Kookooligit Range, which is an oval shield of Pleistocene lava forming the central portion of the island. This shield is about 15 miles wide by 20 miles long. The range begins as a series of sea cliffs and escarpments and gradually rises to an altitude of 1500 feet at the center. Numerous cinder cones protrude from the shield, the highest of which rise to about 2200 feet, the highest point on the island. At least one large caldera and several smaller craters are present on the Kookooligit shield. They are filled with water, and often do not thaw until late July or in August. Although many of the lava flows have a very fresh appearance, no fumaroles, warm springs, or other indications of recent volcanic activity are to be found. The major lava flows apparently date from the early Pleistocene (Hopkins, et al. 1964). Streambeds around the periphery of the Kookooligit Range cut through the lava into earlier deposits, and petrified wood and coal are found in the streambeds. Petrified wood from St. Lawrence has been identified as M. etasequoia (Chaney 1951). Isolated cinder cones are found along the entire northeastern portion of St. Lawrence, as far east as the Punuk Islands, which were at least partially formed by volcanic activity. These cones are probably related to the same volcanic episode which resulted in the formation of the Kookooligit Range. There are no indications of volcanic activity west of the western border of the Kookooligit Range. The major mountains of the eastern end of St. Lawrence are isolated block mountains, the most impressive of which is the rugged Kinnepaghulghat Range which rises to about 1800 VASCULAR FLORA OF ST. LAWRENCE ISLAND 19 feet and covers 40 square miles near Northeast Cape. The smaller Kialegak Range forms Southeast Cape, and Soomagat and Mygapowit Mountains lie in the isolated interior of the island. THE Bertnc LAND BripGE AND REFUGIUM Any study concerned with the history of the biota of St. Lawrence Island must take into account the history of the Bering Land Bridge. The history of the land bridge and its biogeographical implications have been covered in detail elsewhere (cf., Simpson 1940; Hopkins 1959a; Colinvaux 1964 and particularly Hopkins 1967) and need only be summarized here. The floor of the northern part of the Bering Sea and of most parts of the Chuckchi Sea lies only 50 to 100 meters below present sea level. The sea floor is actually a continental shelf which, if emergent, would make Alaska and Siberia a continuous land mass (Fig. 1). The land bridge thus formed would be about 1000 miles wide and stretch from near the Pribilov Islands northward to the vicinity of Point Barrow, Wrangel Island and the New Siberian Islands. It has long been recognized (Simpson 1940) that the mammalian fauna of western North America and Asia showed strong evidence of interchange throughout most of the Tertiary. The obvious and generally accepted conclusion is that a broad land connection existed in the vicinity of the Bering Sea continually, if not continuously, throughout the Tertiary. During the Pliocene, crustal warping in the Bering Sea region resulted in a lowering of the Bering-Chuckchi Platform (Hopkins et al. 1964) to approximately its present level, and the land connection was severed. owever, during the major glacial advances of the Pleistocene, the level of the oceans throughout the world was lowered by as much as 100 meters, due to the vast amounts of water which were tied up in con- tinental ice sheets. If it is assumed that the level of the Bering-Chuckchi Platform was more or less stable throughout the Pleistocene, the obvious implication is that, during each of the four or more major glacial ad- vances, the Bering Land Bridge was reopened. The land bridge would have existed in the form of a vast level plain. The various islands, includ- ing St. Lawrence, would then have been isolated highlands and mountain ranges. For reasons that are not fully understood at present, most of central and western Alaska and eastern Siberia were never subjected to extensive glaciation during any of the Pleistocene glacial advances. Therefore, the Bering Land Bridge not only served as a corridor for the migration of plants and animals between Alaska and Siberia, but it also must have served as a great refugial area for many elements of the arctic biota which elsewhere were either exterminated or driven out by the advancing ice sheets (cf., Hultén 1937). There can be little doubt that the climate of the land bridge during much of the Tertiary was of a more or less temperate nature. Petrified wood of tertiary age occurs on St. Lawrence, and many of the mam- 20 STEVEN B. YOUNG malian species which crossed the land bridge are considered to belong to groups adapted to temperate climates. The Pleistocene climate of the land bridge is less clear. Most workers (cf., Colinvaux 1964) believe that the climate of the land bridge, whenever it was open during the Pleistocene, was essentially arctic and probably no warmer than the present climate of the area. However, there are some anomalous data indicating that the situation may be more complex. For example, Colinvaux (1967) notes a number of genera of the Pleistocene pollen flora not presently on St. Lawrence Island, but which do occur in more southern parts of Alaska. The presence of large amounts of pollen of the Umbelliferae in a submarine core from near Kotzebue Sound (Colinvaux 1964) could indicate the presence of a rich umbelliferous tundra in that area at about the time when the land bridge was submerged for the last time. Tundra of this type is now seldom found north of the Pribilov Islands. The treeless condition of arctic land areas seems to be caused largely by low amounts of available summer warmth, and low summer temperatures are normally associated with a maritime climate, making the treeless tundra a coastal phenomenon. Tundra areas do not exist at low elevations, even in the far north, more than about 200 miles from the nearest large body of water. During the existence of the land bridge, it is assumed that the emergent Bering-Chuckchi platform was at least 1000 miles wide, and it seems reasonable to conclude that the climate must have been highly continental at some periods, with relatively warm summers and cold winters. The presence of small glaciers on the Pribilov Islands ( Hopkins & Einarsson 1966) and on St. Lawrence Island during the Pleistocene are considered evidence that the land bridge climate was colder than the present one. However, no conclusive dating is available for the times when these areas were glaciated and it is quite possible that these minor glaciations were out of phase with the major glacial periods. Small alpine glaciers are usually more dependent on an adequate supply of precipitation and cool summer temperatures than upon the yearly mean temperature, and it is doubtful that glaciers could form near sea level on St. Lawrence unless an extremely maritime climate prevailed. There- fore, it might be considered likely that the glaciers of the Bering Sea islands were formed at the beginning of glacial periods, before the land bridge had emerged and that they did not persist throughout land bridge times. Recent studies (McCulloch, in Hopkins 1967) indicate that at some time during the Pleistocene the timberline was considerably closer to the Pribilov Islands than it is at present, indicating that warmer conditions, at least with respect to summer temperatures, prevailed in Alaska during the Pleistocene than at present. In general, the evidence indicates that the Bering Land Bridge, during the Pleistocene, was 4 broad and probably treeless plain, and that a more or less arctic climate prevailed. From present knowledge, it does not seem justified to conclude that the climate of the land bridge was colder than at present, and VASCULAR FLORA OF ST. LAWRENCE ISLAND 21 there is certainly some evidence that summers in parts of the land bridge may have been warmer than now. WEATHER AND CLIMATE The climate of St. Lawrence Island can be characterized as polar mari- time, with short, cool summers and with a comparatively heavy precipita- tion for an arctic area, Due to the presence of the polar ice pack during the winter and spring, the warming influence of the surrounding sea is not strongly felt during the cold months, and winter temperatures are comparatively low. Climatic data for Gambell and Savoonga are summarized in Fig. 3, including data from some other arctic areas for comparison, As both Gambell and Savoonga are located on the north coast of the island, these locations probably have a more extreme maritime climate than areas in the southern portion. Clear days are a rarity during the summer months at Gambell, but there are sometimes several in a row in the southern part of the Kookooligit Range, although at the same time Gambell Mountain may be blanketed in dense fog. The comparatively low temperatures experienced during June in Savoonga are probably due to the pack ice remaining in the vicinity of Savoonga for a week or two longer than at Gambell. The strong ocean currents which sweep past the Gambell Peninsula apparently are effec- tive in clearing the ice pack earlier there. The absolute maximum tempera- ture recorded at Gambell is 65°F, and it is unusual for the daytime temperature to rise much above 50°F. Therefore, daytime temperatures at Gambell are quite comparable to those recorded along the arctic coast of Alaska and in the Canadian Arctic Archipelago. These temperatures are several degrees lower than those recorded on the mainland Bering Sea coast of Alaska. No climatic data have been gathered from southern coastal and interior portions of St. Lawrence, but clearer weather in these areas probably allows temperatures to rise to a slightly higher level than at Gambell. Conversely, increased radiational cooling in these areas can make them more prone to summer frosts, which aimost never occur at Gambell. Winter temperatures on St. Lawrence are comparatively high for an arctic area. The mean January temperature at Gambell is 20°F higher than at Point Barrow, and short periods of thawing tempera- tures may occur at any time of the year. Precipitation on St. Lawrence is unusually high for an arctic area. It is responsible for the extreme wetness of many of the tundra areas of the island, and also for the relatively large areas covered by permanent ice and snow. Snowfall is exceedingly variable, but it may reach as high as 190 inches. Most of the snow which falls on exposed areas is blown out onto the icepack, but large amounts are also deposited in cirques and ravines. Mean wind speed throughout the year at Gambell is 17.8 mph. Calm days are rare, and winds of gale force may rise suddenly at any time. as STEVEN B. YOUNG aa . Dae. Oe ze E a 10 . a as E a ae — + a — . a = -20 s 50 % 7 c c Rs : : : ee : es Ate SAVOONGA BARROW a 0 ALASKA ICELAND UPERNAVIK GREENLAND SVALBARD 3. Gra phs showing mean temperature and precipitation by month for two stations on St. lente Island, with similar data from other far northern stations for compari During late summer and autumn, violent storms, usually from the south- west, may last for days or weeks at a time. € growing season on St. Lawrence usually begins in early June when the snow begins to melt in exposed areas. By late June the willows are VASCULAR FLORA OF ST. LAWRENCE ISLAND 23 in leaf, and most of the early tundra flowers, such as Lloydia, Anemone, Ranunculus, Primula, and Pedicularis are in bloom. Summer lasts through July and the first two or three weeks of August; by late August, most plants have completed their life cycles, and the leaves on willows and Arctostaphylos have begun to turn. Early September brings the first snow and freezing weather, and the ice pack begins to form in late October. PERMAFROST, FROZEN GROUND FEATURES AND SOILS Permafrost. Perennially frozen ground underlies most of the land area of St. Lawrence Island. The only exceptions seem to be the beds of lakes with a depth of over four feet. This is undoubtedly because lakes on the island do not freeze to a depth of more than about four feet during the long but only moderately cold winters. The lack of permafrost beneath lakes probably has no correlation with the depth of permafrost in terrestrial locations. There are no data available on the depth to which permafrost extends on St. Lawrence. The depth of the active (seasonally thawed) layer of the soil varies greatly depending largely on conditions of drainage and vegetation. The active layer is most shallow in wet tundra with a complete vegetation cover, particularly where Sphagnum is abundant and the depth of the thaw may be no more than six inches during the entire summer. In more mesic situations, the depth of thaw averages from two to three feet, with deeper thawing occurring along stream banks, on solifluction lobes and on raised hummocks. The depth of thaw of raised beaches, barrier beaches, etc. is not known. I found permafrost at a depth of about three feet in a raised beach near Gambell in early July, indicating that the total depth of thaw is considerably greater than three feet. Frozen Ground Features. All of the soil features commonly associated with intense frost action (cf., Flint 1957) occur on St. Lawrence Island. Frozen ground features have a considerable and not entirely deleterious effect on the constitution of local vegetation. In particular, the minor relief afforded by raised features on patterned ground often allows the development of a comparatively complex vegetation in areas which otherwise would support only bog. Patterned ground is found on all the low-lying areas of St. Lawrence Island, and also on many alpine and fell-field terrains. Where it is wet and low-lying, the commonest form of patterned ground is a system of low-centered polygons. The relief of these features is so slight that it is not readily visible from ground level, and the effect on the vegetation is correspondingly small. In other areas, high-centered polygons may rise to two or three feet above the surroundings. Their effect on the vegetation is considerable, and there are a number of species that are essentially confined to these areas. On flat alpine areas and fell-fields, patterned ground usually occurs in the form of sorted stone rings. With increasing slope, the rings are distorted into ovals and ultimately into parallel strips. 9A STEVEN B. YOUNG These features are usually associated with highly unstable soil and intense frost heaving, and the poor vegetation of these areas reflects this. Frost boils are of common occurrence on wet tundra. They are found by the entrapment of semiliquid clay between the permafrost and a contracting layer of frozen soil on the surface. Ultimately, the frozen surface cracks open, and the clay spreads out over the surrounding vegetation, usually destroying it. Frost boils are revegetated slowly, and they are often visible for many years after their formation. Solifluction is common where there is some slope and a fairly thick mantle of soil or gravel. Solifluction tends to concentrate soil at the edges of advancing solifluction lobes which are raised somewhat above the surrounding terrain, with the result that they are comparatively well drained and deeply thawed during the summer. The edges of these lobes often support a comparatively lush vegetation, and there are some species which are more or less restricted to such areas, at least on St. Lawrence Island. Soils. To my knowledge, no work has been done on the soils of the island. However, similar soils on the Arctic Slope of Alaska have been studied intensively (Tedrow & Cantlon 1958; Drew & Tedrow 1962). Tedrow and Cantlon (loc. cit.) distinguish a single zonal soil in arctic areas designated as arctic brown soil. It is a product of podsolization, and develops only under conditions of adequate drainage, a deep active layer, and moderate soil particle size. As a consequence, this type of soil is seldom developed over large areas. On St. Lawrence, arctic brown soil is found along stream banks, on solifluction lobes and particularly on the stabilized backshores of barrier beaches. The total area involved is probably less than 5 per cent of the land area of the island. With increasing wetness, arctic brown soils grade into tundra and ultimately bog soil. This is the most important soil type on St. Lawrence Island and probably covers over half the island’s land area. With decreasing depth of bedrock, arctic brown soil grades into a lithosol, while with increasing particle size it grades into a regosol. The distinction between these two types is often not clear, as in the case of a slope or plateau mantled with frost-riven rock fragments. In any case, “soils” of these types are of major importance on St. Lawrence Island, covering most of the mountainous areas, fell-fields, and many of the less stable beach ridges. On a local level, variation in the nature of soil is often closely correlated with various types of patterned ground, and it has been proposed that arctic soils should be classified on the basis of both the genetic soil profile and the patterned ground (Drew & Tedrow 1962). It is axiomatic that the type of soil is closely correlated with vegetation. Bog soil usually supports a closed community consisting of a few species of grasses and sedges, while arctic brown soils commonly support a more complex community of many species of plants. Other soil types usually support a poorly developed vegetation, although the Elymus zone on the foreshores of beaches is an exception to this rule. VASCULAR FLORA OF ST. LAWRENCE ISLAND 25 VEGETATION AND HABITATS The vegetation of St. Lawrence Island consists entirely of a low, generally herbaceous growth which ranges from essentially complete cover in some wet areas to virtually no cover, at least of vascular plants, on alpine rock deserts and lava flows. However, lichens, particularly species of Cladonia and Cetraria, are often common in these areas. Tussock forming species, of which Eriophorum vaginatum is the most important, are rare or absent on St. Lawrence. Tussock tundra does not occur on the island, although it is often well-developed on the mainland of northern and western Alaska. Shrubby species are also of little im- portance in the St. Lawrence Island vegetation. The only common shrub willow is Salix pulchra, and this species normally does not exceed one foot in height, although in riparian gravel plants may be two feet or more tall. There are reportedly some areas on the southern slopes of the mountains on the eastern end of the island which support shrubby growth. I have not been able to find these areas and cannot comment on the species involved. A reasonable breakdown of the habitats on the island would distinguish four major types, each with a corresponding vegetation formation. The types are: bog and wet tundra; alpine and fell-field; mesic tundra; and aquatic habitats. The first two types are, in terms of area, by far the most important. There is a strong correlation between the major habitats and the soil types discussed in the previous section. A number of minor habitats are also distinguishable on St. Lawrence Island. Generally, these result from the action of man or other biotic factors. Wet Tundra. Wet tundra is, in terms of area covered, the most im- portant vegetation formation of St. Lawrence Island. It covers approxi- mately half of the land area of the island. Wet tundra is most commonly developed at low altitudes, and it is most prevalent on the level plains of the eastern end of the island. However, small patches of typical wet tundra occur in alpine areas wherever there is impeded drainage. On many of the rolling plateaus there is not enough relief to provide adequate drainage, and here also wet tundra is dominant. The vegetation cover on wet tundra is usually close to 100 per cent. Exceptions occur in areas where frost boils are abundant or where intense frost action disturbs the vegetation. In the wettest tundra, Carex aquatilis is the most abundant species, and may form nearly pure stands over large areas. In better drained areas, Eriophorum angustifolium becomes dominant, with Dupontia Fischeri also often being of major importance. Wet tundra areas are usually dotte with Sphagnum hummocks, frost boils and raised polygons. The relief of these features is often enough to have a considerable effect on drainage, with the result that many wet tundra species are found only in these places. The species most commonly found on hummocks include: Salix arctica, §. pulchra, Rumex arcticus, Saxifraga heiracifolia, S. punctata, 5. 26 STEVEN B. YOUNG nudicaulis, Rubus chamaemorus, Vaccinium vitis-idaea, Senecio atropur- pureus and Petasites frigidus. Alpine Areas and Fell-fields. The term alpine as used here does not denote any particular amount of elevation, as typical alpine habitats extend down to sea level on many parts of the island. There is no clear-cut distinction between alpine areas and fell-fields, but the latter term is generally used for areas of unconsolidated rock and gravel, whether they occur on mountains or not. Sizable areas in the interior of St. Lawrence Island are flat and often raised only a few feet above the surrounding wet tundra, but nevertheless have developed a typical open fell-field vegetation containing essentially the same species as those found in the higher mountains. Alpine and fell-field vegetation is developed on 30 to 40 per cent of the land surface of St. Lawrence. It ranges from less than 50 per cent cover on unconsolidated gravel and rock to no cover on lava flows and rock deserts at high elevations. In general, conditions in alpine and fell- field areas are rather dry, but the impermeability of the substrate allows water to be trapped in many small pockets and seepage areas, even at higher elevations. A few species, e.g., Ranunculus glacialis, Claytonia acutifolia and Polygonum bistorta, are usually confined to these areas. Some gravel flats at low elevations also may be damp, or even saturated with water. There, frost action is often extremely intense and the thin vegetation cover probably is due to soil instability. One can often find sizable clumps of vegetation which have been uprooted and overturned by frost action on wet gravel flats, Rock deserts are found in the mountain ranges on the eastern and western ends of the island, particularly at the higher elevations of the Poovoot Range near Boxer Bay. The substrate here consists of rather large fragments of frost-riven granite. Soil is found only in small pockets where the mantle of broken rock is thinnest, and over large areas there may be no significant growth of vascular plants. However, lichens of several genera are often abundant on the surface of the rocks. Lava flows occur in the central and southern portions of the Kookooligit Range. The lava here is relatively unweathered, and usually supports a weakly developed vegetation, similar to that found on other rock deserts. In the northern part of the Kookooligit Range, the lava is softer, more deeply weathered, and is often cut by deep stream banks. A number of species are characteristic of these areas, and some of them are not found elsewhere on the island. Examples are: Saxifraga flagellaris, Chrysosplenium Wrightii and Phyllodoce coerulea. The first two species are probably calciphiles. e alpine habitats of St. Lawrence are so varied that it is difficult to characterize them in terms of the species present in the plant com- munities. The following species commonly occur on the wetter alpine habitats, and they are often abundant: Lycopodium selago, Deschampsia VASCULAR FLORA OF ST. LAWRENCE ISLAND 27 caespitosa, Juncus biglumis, Luzula confusa, Salix phlebophylla, S. polaris, Oxyria digyna, Saxifraga punctata, Sedum rosea, Cassiope tetragona, Primula tschuktschorum and Artemisia arctica. In drier areas, species such as Hierachloe alpina, Trisetum spicatum, Arctagrostis latifolia, Carex nesophila, Arenaria arctica, Potentilla ssp., Oxytropis nigrescens, Pedic- ularis lanata and several species of Artemisia are often common. Mesic Tundra. The term mesic tundra as used here is something of a catchall phrase, since it includes a number of superficially unrelated habitats such as sandy backshores, riparian gravel situations and upland tundra. However, in all of these habitats the active layer of the soil is comparatively deep and a zonal soil (arctic brown soil) has been de- veloped. The area covered by mesic tundra on St. Lawrence Island is comparatively small, perhaps 5-10 percent of the total land area of the island. Except along the coast, mesic tundra is confined to areas in the central and particularly the south-central portion. In other areas it is usually confined to small patches on solifluction lobes, along streambanks and on raised beaches. Floristically, mesic tundra is the richest habitat on the island. Perhaps 90 per cent of the non-aquatic flora of the island can be collected on mesic tundra, and the majority of the rarer terrestrial species are found only in these areas. Examples are: Veratrum album, Ranunculus Turneri, Gentiana auriculata and Campanula uniflora. A number of other species are common to abundant on mesic tundra, but are practically unknown on the rest of the island. Among these are: Calamagrostis canadensis ssp. Langsdorffii, Juncus castaneus, Potentilla palustris, Rubus arcticus and Epilobium anagallidifolium, all of which grow on mesic tundra in interior portions of the island. Such species as Aconitum delphinifolium, Primula borealis, Pedicularis verticillata, Chrysanthemum arcticum and Artemisia Tilesii are often abundant on backshores but rare elsewhere. Salix Chamissonis, Silene acaulis, Wilhelmsia physodes, Epilobium latifolium and Pedicularis Oederi are confined to riparian gravel situations. A characteristic type of mesic tundra is developed on the foreshores and backshore areas of the 200 or more miles of barrier beach surrounding the island. In many areas, the lagoons behind these beaches have been reduced to little more than ephemeral ponds and puddles, and the back- shore may be a mile or more wide. The flora found on backshore and foreshore areas on the periphery of the island is quite uniform. The fore- shore communities reach from the level of the highest storm tides to a point somewhat behind the greatest elevation of the barrier beach. As the beaches are normally rather steep on the seaward side and slope away gradually to the landward, the foreshore community normally covers a much smaller area than does the backshore community. The foreshore community is always dominated by a thick growth of Elymus arenarius. Between the sea and the Elymus zone is often a narrow zone in which Honckenya peploides, Mertensia maritima and Senecio pseudo-arnica 28 STEVEN B. YOUNG are common; higher up the beach Conioselinum chinense, Angelica lucida and Lathyrus japonicus may be mixed with the Elymus, but none of these species is common. The backshore community is neither as lush nor as thick as that of the foreshore, but it is much more complex, and as many as 75 species may be found on an area of backshore of no more than a few acres. Among the more common species are: Equisetum arvense, Festuca brachyphylla, Phippsia algida, Luzula tundricola, Salix reticulata, S. ovali- folia, Cerastium Beeringianum, Sagina intermedia, Melandrium apetalum, Polemonium boreale, Pedicularis verticillata, Artemisia Tilesii, A. arctica and Chrysanthemum arcticum. The floristic richness of the backshore zone is due to its generalized habitat in which alpine species such as Papaver radicatum, Saxifraga flagellaris and Androsace ochotensis may be found within a few feet of aquatic species such as Hippuris vulgaris and Ranunculus Pallasii. Aquatic Habitats. Although a large proportion of the land area of St. Lawrence is covered by fresh water lakes and ponds, the aquatic flora is usually poorly developed, and many of the tundra ponds contain no true aquatic plants. The shallow edges of the ponds usually support a dense growth of semi-aquatic species such as Arctophila fulva, Eriophorum angustifolium and Carex aquatilis, while the deeper areas may be devoid of vascular plant life. A few species of true aquatics are widely distributed over the entire island; among these are Ranunculus hyperboreus, R. Pallasii, Potentilla palustris and Hippuris vulgaris. In a small area in the south central portion of the island, a true aquatic flora is developed and ten or more species of aquatic plants are found there which are other- wise unknown on the island. Many are low arctic species and make up the major proportion of the low arctic elements of the St. Lawrence flora. Minor Habitats. Several habitat types which do not fit into the major divisions discussed above occur on St. Lawrence. Many appear to be dependent on large quantities of nitrogen introduced into the soil by the activities of man and other animals. Bird cliffs are found along much of the more rugged coastline of the island. In areas where nesting activity is most intense, the soils consist almost entirely of the droppings of sea birds and the plant community consists of the nitrophiles Phippsia algida and Cochlearia officinalis. On the peripheries of the main breeding areas, other nitrogen tolerant species such as Claytonia sarmentosa, Saxifraga rivularis, S. punctata and Sedum rosea are common. Human habitation sites. During the thousands of years that man has inhabited St. Lawrence, large amounts of refuse from human habitations have been deposited. The most extreme examples of this are found in some of the ancient village sites, such as Kialegak, Kookoolik and Sevuokuk where refuse mounds of several acres are found. They consist mainly of animal matter, particularly the bones of whale and walrus. Because of the cold climate, the nitrogen is released extremely slowly and human burial sites which are 500 to 1000 years old (H. G. Bandi, personal VASCULAR FLORA OF ST, LAWRENCE ISLAND 29 communication, July 1967) are still visible as areas of slightly more luxuriant plant growth. When undisturbed, ancient village mounds have a vegetation quite similar to that of mesic tundra, because of good drainage. Growth is unusually rank, however, and a few species such as Pedicularis verticillata and Artemisia Tilesii predominate. Ancient village sites which lie close to modern villages are usually honeycombed with pits, dug by the natives in search of artifacts. Because of the underlying permafrost, these pits are often damp or even filled with water and their sides support a lush growth of Montia fontana, Koenigia islandica, Stellaria humifusa and Cochlearia officinalis. The entire coast of St. Lawrence is dotted with the remains of single dwellings which can be seen for miles because boat racks, made from the jawbones of right or bowhead whales are often still standing. These individual sites are only a few square yards, but they support a flora which is the same as that of the larger village sites. Animal burrows. Many gravelly areas have been extensively tunneled by arctic foxes (Alopex lagopus) and arctic ground squirrels (Citellus parryi). Tunneled areas usually support a dense growth of Arctagrostis latifolia, a species which otherwise seldom occurs in pure stands. Waterfowl resting areas. Large flocks of migrating and molting water- fowl, mostly emperor geese (Philacte canagica) and snow geese (Chen hyperborea), congregate each year on certain parts of the island. The most favored points are at the extreme ends of large lagoons or near small ponds on the backshores near them. The soil in these areas is considerably enriched, and the grazing of the geese probably has some effect on the vegetation. The most common species in these areas are Carex glareosa, C. rariflora and C. subspathacea. On the bottoms of the shallow, ephemeral pools found in these areas, the same species as those occurring in pits of old village sites are usually abundant. Some pools may also support a dense growth of Callitriche verna. Reindeer carcasses. At one time St. Lawrence supported an introduced population of reindeer which has been estimated to have contained up to 10,000 animals and reindeer herding was an important native industry. Apparently the herd grew too large for the carrying capacity of the range and in the late 1940's nearly all the herd died off, leaving carcasses strewn over the entire island. Fay and Cade (1959) mention that the vegetation in the vicinity of the carcasses was considerably more lush an in surrounding areas, but by 1966 this phenomenon had disappeared, although it is still possible to find reindeer skeletons on the tundra. It has been claimed that the poor vegetation of St. Lawrence is the result of overgrazing by reindeer, but this seems highly improbable. The major food of the reindeer presently found on the island is lichens, and the herd is usually found in the high barrens of the Kookooligit Range, where few vascular plants grow, but where a relatively rich lichen flora has developed. The absence of shrub and tussock tundra on St. Lawrence 30 STEVEN B. YOUNG seems to be correlated with the almost complete absence of tussock- and shrub-tundra forming species. The small reindeer herd which is now present on St. Lawrence probably numbers less than 500 animals and it seems to have no noticeable effect on the vegetation. It is almost inconceivable that reindeer have selectively eliminated any species from the island. Construction. Three airstrips and several small U.S. Government in- stallations, most of which are now abandoned, have been constructed on St. Lawrence during the last few years. Construction has been on such a small scale that it has had little effect on the vegetation of the island. The major effect has been produced by the mining of gravel for the air- strips, resulting in the formation of several shallow ponds in the neighbor- hood of Gambell and Northeast Cape. Organic matter has not yet built up in these ponds and the typical wet tundra species are for the most part absent. Instead, such species as Calamagrostis deschampsioides, Festusca brachyphylla and Stellaria humifusa are found growing semi- immersed in the ponds. The habitats of certain areas also have been disrupted by the passage of tracked vehicles. For example, the pebble beach behind Gambell was once covered by a thin, dry tundra, according to the older natives, but the area is now mostly sterile and supports only a few spears of Elymus arenarius. Riparian gravel situations. Some of the large rivers on the island have developed gravel bars of some size. Where they are raised to such an elevation that they are seldom inundated, a typical mesic tundra formation develops, but where they are flooded, a community consisting mainly of Salix pulchra and Epilobium latifolium has developed. At a slightly higher level are found, in addition to the above species, Wilhelmsia physodes, Parnassia Kotzebuei and Silene acaulis, all of which are rare in other habitats. Snow patches. Since the permanent snow patches on St. Lawrence Island contract steadily until early September, bare soil is constantly being exposed during the summer. A few species which can complete their life cycles in a short period of time can be found flowering at the edges of snow patches in late August. The commonest of these are Chrysosplenium tetrandrum, Saxifraga rivularis, S. punctata and Primula tschuktschorum. History or BoranicaL COLLECTING Although the Billings expedition of 1791, including the naturalists Carl Merck and John Main, made a landing on St. Lawrence, the first botanical collecting of any consequence was done by A. L. von Chamisso and J. F. von Eschscholtz of the Kotzebue expedition of 1816-17. They landed at a village near Southeast Cape (undoubtedly Kialegak, which must have been occupied at that time) on July 27, 1816 and again on July 10, 1817. Specimens of perhaps 60 species of vascular plants were collected, in- cluding the type specimens of Eriophorum callitrix and Cardamine VASCULAR FLORA OF ST, LAWRENCE ISLAND 31 purpurea. Many of the specimens from this expedition appear to be lost, and there are few specimens collected by Chamisso and Eschscholtz in U.S. herbaria. However, a detailed list of specimens collected was pub- lished (Chamisso & Schlechtendal, 1826-1836). Saint Lawrence was apparently not visited again by a botanist until 1879 when F. R. Kjellman of the Nordenskjold Vega expedition spent from July 31 to August 2 at some area on the northwest coast of the island. The exact location of the Vega’s landing is not known, but Kjellman’s plant list indicates that he did not collect in any of the higher alpine regions, and it seems likely that the landing was made in the vicinity of Northwest Cape. Several species (e.g., Pyrola grandiflora, Andromeda polifolia and Linnea borealis) included in Kjellman’s collec- tions are now rare or absent in the northwestern portion of the island. The results of his work on St. Lawrence were published in the form of a flora of the island (Kjellman 1882) in which 113 species, including those collected by Chamisso and Eschscholtz and by Kjellman himself are listed. He was particularly impressed by the strongly arctic vegetation. His observations indicate that it was markedly different from that of adjacent mainland areas even before the introduction of reindeer to the island. In 1881, the steamer Corwin, in search of the DeLong expedition, landed on St. Lawrence on May 28, June 8, and July 4 with the naturalist John Muir aboard. The landing was made somewhere on the northwest coast. Muir, too, was impressed with the bleak and barren aspect of the island. He writes (Muir 1918): Saint Lawrence Island, as far as our observations extended, is mostly a dreary mass of granite and lava of various forms and colors, roughened with volcanic cones, covered with snow, and rigidly bound in ocean ice for half the year. Muir’s collections, now in the Gray Herbarium, contain few specimens from St. Lawrence. He (1918) mentions that Silene acaulis, Andromeda, Ledum, Linnaea and “several species of Vaccinium” were common. These are all rather rare on the island at present. Only two species of Vaccinium are known to occur there, one of which, V. uliginosum, is known only from a couple of isolated localities. On July 13, 1899, F. V. Coville and T. H. Kearney of the Harriman Alaska Expedition landed at Northeast Cape, apparently for one day only. Their small collections, now at the U.S. National Herbarium, contain a few species which were previously unreported from the island. In the summer of 1931, H. L. Mason visited Savoonga on June 26 and July 9, and collected at Aivichtook Lagoon on July 10 and the Naskok Lagoon on July 12. The main collection is at the California Academy of Sciences, with a number of duplicates at the Gray Herbarium. During the summer of 1931 and several succeeding summers, Otto William Geist made ethnographical and archaeological studies on the island. Geist traveled widely around the island by boat and apparently he was the first 32 STEVEN B. YOUNG white man to travel extensively on the south side of the island. Geist’s col- lection of plants, mostly made during the summer of 1933, are located in Stockholm, the Gray Herbarium and the University of Alaska Herbarium. Jacob Peter Anderson, the indefatigable collector of the Alaskan flora, spent September 3, 1938 at Savoonga and the following day at Gambell. The numbers of the specimens supposedly collected by Anderson on St. Lawrence are not all consecutive, indicating that there may be some confusion in the labeling. This would explain the fact that Anderson's supposed St. Lawrence collection, made during only two days, and in areas which the author has visited repeatedly, contains several species which are otherwise unknown from the island. Anderson’s collections are in the Iowa State University Herbarium, with many duplicates in Stock- holm, the Gray Herbarium and the University of Alaska Herbarium. Hultén (1940) lists several other small collections from St. Lawrence. Among these are: E. O. Campbell in 1903; L. J. Palmer in 1921; and K. L. Chambers in 1938. He (1941-1950) also lists a number of specimens collected by George Haley, supposedly on St. Lawrence Island. In his list of botanical collections from Alaska, Hultén (1940) makes no mention that Haley ever visited St. Lawrence, and he also notes (Hultén 1946 ) that the labels of Haley’s collections are not always reliable as to location. Several of the species supposedly collected from the island by Haley have not been found by other workers. It seems probable that the specimens were obtained elsewhere, perhaps on the Pribilov Islands. Between 1940 and 1966, when my own work on St. Lawrence began, a few small collections were made on the island. The most important of these were made over a period of several years by Dr. Robert Rausch and Dr. Francis H. Fay of the Arctic Health Research Laboratory at College, Alaska, who collected single specimens from several parts of the island. The more recent of these have been placed at my disposal. The older collections were identified by Dr. John H. Thomas of the Dudley Herbarium of Stanford University. Dr. Thomas kindly sent me a list of the species he had identified. Porsild (1965) mentions a single collection of Primula tschuktschorum made at Boxer Bay by Franz Sauer in 1960. I have no further information on this collection. My own work on St. Lawrence Island took place during the summers of 1966-67. I spent a total of about five months there, during which time I collected 1100 sets of specimens. The major collection specimens loca- tions are shown in Fig. 2, but many were collected on walking trips between the locations indicated on the map. The most intensive collecting was done in the Boxer Bay area, along the Koozaata River and in the Kookooligit Mountains in the vicinity of Savoonga. I was able to spend less times on the eastern end of the island and consequently did not visit all of the mountain ranges in the area. My collections include specimens of 235 species, of which about 60 have not been reported from the island before. VASCULAR FLORA OF ST. LAWRENCE ISLAND 33 ANNOTATED List OF SPECIES General Notes. The following is a list of the species of vascular plants which are known to occur on, or have been reported from, St. Lawrence Island. The arrangement of the species follows that of Hultén (1968a). Species listed numerically and not enclosed in brackets are accepted as being members of the present St. Lawrence Island flora. Bracketed species have been reported in the literature as occurring on the island, but, for one reason or another, exclusion from the recorded flora seems warranted. The relatively small number of specimens collected on St. Lawrence by earlier workers are scattered in herbaria throughout the world. At the outset of the present study, it was felt that the limited amount of time and money available were best spent in field work on the island, rather than in trying to assemble all earlier specimens. Therefore, it is possible that some of the species excluded from the flora are represented by specimens which I have not seen. However, the majority of the unsub- stantiated reports seem to be based on specimens which are either in- correctly labeled as to collection location or which were misidentified. The nomenclature used generally follows that of Hultén (1968a, 1968b). No attempt has been made to include synonymy except in the cases where a species is treated under a different name in other major works on the arctic flora, as for example Porsild (1964) and Tolmatchev (1960-1966). In order to reduce repetition, the author's name is listed only for the first specimen in a sequence of several specimens of the same species under the designation, specimens examined. All specimens listed without indication of their present location are deposited in the Gray Herbarium. The overall distributions of the species in the St. Lawrence Island flora have been treated in more detail than is customary in a paper of this kind. Since the second section deals with factors affecting the distribution of arctic plants, it seemed important to include a fairly detailed picture of the distribution patterns of the St. Lawrence Island flora. The northern limit of the distributions of the species under discussion is characterized by a zone number ranging from 1 to 4. An explanation of the zones is given later in this paper, and a map of the zone boundaries is given on page 94. The ranges of most of the species treated here are shown on dot maps by Hultén (1958, 1962, 1968a), T olmatchev (1960-1966) and Porsild (1964). I have tended to be somewhat conservative in the taxonomic treatment of many of the species discussed below. In several cases, groups of specimens which many workers would place in two separate species are “lumped,” as in the cases of Saxifraga davurica, Rubus arcticus and Polemonium boreale. In these cases, my field experience in western Alaska has led me to believe that all of the specimens of these groups belong to a single population, at least on St. Lawrence Island. In the case of Rubus arcticus, for example, it is possible to collect specimens which many 34 STEVEN B. YOUNG workers would regard as belonging to two separate species from the same clone. LYCOPODIACEAE 1. Lycopodium selago L. ommon in most alpine situations. Occasional on backshores and hummocks of wet i sak Although not all specimens from the island have the appressed leaves typical ssp. appressum, field observations nica that the contention of Hultén (1968a) that two subspecies of L. selago occur on St. Lawrence is not justified. SPECIMENS EXAMINED: Young 55, Tapphook; 251, Savoonga; 278, Northeast Cape; 369, Kialegak; eo: Siknik; 614, Boxer ve 741, Gambell. Mason, July 12, 1931, Pe oa clavatum L. mall, sterile clumps were found scar el on rocky alpine areas. The specimens saputeetty belong to ssp. monostachyon. The presence of this species on_ St. Lawrence is probably due to the continuous arrival of spores from adjacent mainland areas seagice i Paro bed a. oung 53, Tapphook Mountain; 210, yah ator 328, North- se eshte “555, ( Gacdtnks “TL Boxer Bay. No previous reports. Range: circumpolar, ow arctic and ee regions, with stations in the southern hemisphere. Northern limit: upper zo 3. in alpinum L. ncommon on raised beaches and along gravel stream banks. Not found in the higher ee areas. NS EXAMINED: Young 97, Kookooliktook River; 265, Ataakas Camp; 327, Nuetheust Cape; 378, Kialegak; 550, Gaedtuk. No previous reports. Range: nearly circumpolar, but with gaps in Canada and Siberia. Northern limit: upper zone 4, reaching zone 3 in East and West Greenland. EQUISETACEAE 4, oe scixpokicr. Michx. delicate individuals are found in grassy tundra, usually alon a stream banks. Other th y gs an size, can are no morphological features which reliably distinguish be- ver these two form ECIMENS (E oe tt fluviatile L. ampl. Ehrh. , Hultén (1968a shows a station for this species on St. Lawrence. Specim which I consider ens be abnormal individuals of E. arvense can be mistaken for E. fuviatile, which I have not collected on St. Lawrence. 5. Equisetum palustre L. Small, sterile specimens collected at a —— ogg on a mudbank in a slough of the Koozaata River are best identified as thi SPECIMEN EXAMINED: Young 1354, Koceant "Rive . No previous reports. Range: nearly circumpolar, low arctic and temperate cee ‘Northern limit: northern zone 4, reaching zone 3 at Vaigatch Island. 6. Equisetum arvense L. Rather common along the shores of lagoons and small lakes, and at the edges of frost boils and other disturbed areas on wet tundra. Sterile shoots are seldom more VASCULAR FLORA OF ST. LAWRENCE ISLAND 35 than 5 cm tall and do not develop a central axis. Fertile shoots are only occasionally ool SPECIMENS EXAMINED: Young 73, Tapphook; 215, cnegel tek Kialegak; 575, Gae dtuk. Mason 6086, Savoonga. Several other re eports. Range: mpolar, arctic and a regions. Northern limit: conforms almost perfectly f The northern edge of POLYPODIACEAE 7. Cystopteris fragilis (L.) Bernh. A single station was found on a talus slope on the west bank of the Boxer River, about four ‘ileg upriver from Boxer Bay. None of the specimens have mature sori, so it is impossible to tell whether i! represent ssp. Dickieana or ssp. fragilis. SPECIMENS EXAMINED: Young 1311, Boxer River. No previous reports. Range: circumpolar, arctic and ee regions, also with stations in the southern hemi- sphere. Northern limit: 8. Dryopteris fragrans (L.) Schott Occasionally found in crevices in nite barren lava fields along the southern edge of the Kookooligit Mountains. Som specimens are unusually delicate, with fronds less than 5 cm tall and with the tachi decides and n nekily devoid of sca sa . These speci- a nil cloned ow an ecologically induced condition rather a genetic race. $ EXAMINED: Young 549, 1383, near Gaedtuk. No ak reports. Range: ne alti cir cumpolar but rare in Greenland and Europe. Northern limit: barely aes the southern border of zone SPARGANIACEAE 9. Sparganium hyperboreum Laest. Fertile specimens were found in a small pool on a bank of the Koozaata River pbest five miles upriver from Gaedtuk. ri eile specimen collected in a small pool n sp a ales is ey also this species SP EXAMINED: Young 454 (?), Kialegak; 1347, Koozaata River. No fa i s sepa ange: circumpolar, mainly arctic. Northern limit: northern zone 4, teaches the lower edge of zone 3 in West Greenland and northern Alaska. POTAMOGETONACEAE 10. Potamogeton perfoliatus L. it Found at a single station in the upper reaches of the Koozaata River, where it formed an extensive patch in about five feet of water. The specimens clearly be long to ssp. Ric ae a well defined American race which is occasionally treated as ecie: SPECIMENS eecieie: Young 1342, Koozaata River. No previous reports. Range: (P. perfoliatus sensu lato) circumpolar, low arctic and temperate regions. Northern limit: zone 4, reaching southern zone 3 near Scoresby Sound, East Greenland. 11. Potamogeton subsibiricus Hagstr. (P. Porsildorum Fern. ) Sterile specimens were found on the bottom of the Koozaata River near Gaedtuk and in several small pools nearby. SPECIMENS EXAMINED: Young 1341, Gaedtuk. No previous reports. Range: three small, very disjunct areas: the lower Yenesei Basin, Alaska, and southern Hudson Bay. Northern limit: not clear. 12. SC vaginatus Tur m on the bottom of ie Koozaata River near Gaedtuk; usually found in two to six ae of water. SPECIMENS 1346, Gaedtuk. No — reports. Ran not —— known. Apparently more or i circumpolar in arctic and sa ceeale regions. Northern limit: not clear 36 STEVEN B. YOUNG JUNCAGINACEAE 13. Triglochin palustris L. Sterile specimens were found at one station, on a mud bank in a slough of the Koozaata River. The single collection of Equisetum palustre was made at the same Opec EXAMINED: Young 1348, Koozaata River. No previous si te Range: circumpolar, arctic and temperate regions, not extending north into arctic Siberia. Northern limit: does not conform well to any zone boundary; eee zone 3 in Greenland. GRAMINEAE 14. Hierochloe alpina (Sw.) Roem. & Schult. Of poe occurrence on most of the drier rocky and alpine ar oi SPECIMENS EXAMINED: Young 54, Tapphook; i Savoonga; 3 2, Kialegak; 566, 1340, Gaedtuk. Several other reports. Range: ia pte Northern limit: closely approximates the northern edge of zon 15. Hierochloe pauciflora R. Br. sani in dry alpine beat PECIMENS EXAMINED: Young 226, ven cel 301, Northeast Cape. Also reported Be Kjellman (1882). Range arctic; nearly cir lar, but not known from Green- land or northern Europe. Northern limit: alisely's approximates northern edge of zone 2 throughout its range. 16. Alopecurus alpinus Smith Rather rare; most commonly found in cirques and on talus slopes in the so western portion of the island. Most specimens have long awns inserted near the tag of the lemma. They can therefore be placed in on Saag he This is a rather well- defined race of the Beringean area (Hultén, 1942), but it is less distinct on St. Lawrence than in more southern areas, and transitions between ssp. Stejnegeri and ~ son io occur on the island. g 628, Boxer Bay; 1411, near Southwest Cape. Gliaiabotlaie 66. Andarsonk 5169. Geist, 1933. Range: circumpolar, arctic. Northern limit: occurs throughout zone 1. Not treated by Hultén in Circumpolar Plants (1962). ii, "Pps algida (Soland.) R. Br. nitrophile, this —— is abundant and often dominant on bird cliffs and on old vile sites tes. Elsewh it is uncommon and Ng aigee 9 The distinction between on specimens from St. Lawrence “Island. Hultén , 1950, 1968b) considers a single specimen (Kjellman, Aug. 1, 1879, pro parte) to be P. concinna; this is supposedly only specimen from North America. cage to ‘Hultén (1950), P. algida not a nitrophile. Saint Lawrence soc mag scistcsaly have a single stamen, _ there is me a that two g 5 5 a a 5 er 2) 8 8 i) at 3 5 SPECIMENS EXAMINED: Young 230, 231, — a Northeast Cape; 689, . Bay; 735, Gambell. Several other reports. Range: P. algida) circumpolar, Also known from two alpine stations in western US. ke limit: found scout zone Papel concinna) See under P. algida. VASCULAR FLORA OF ST. LAWRENCE ISLAND 37 18. Saeeant latifolia (R. Br.) Griseb. Fairly common on drier habitats, particularly near the burrows of ground squirrels and arctic aes Occasional on backshores. Most mature specimens have the elongated, z . MINED: Young 70, 120 Tapphcoks 228, Savoonga; 317, No patos ates “146, ‘ealegaks 532, Siknik; 679, Boxer feos 792, Gambell. cna other reports. Range: circumpolar, arctic. Northern limit: 19. Calamagrostis canadensis (aie ) Beauv. ndant on mesic tundra in the central and southern portions of St. Lawrence. Rare or absent elsewhere. Saint Lawes specimens are high grown, with large, open ston Hied are aererabhe to ssp. Langsdorffi. INED: Young 712, Boxer Bay; 1397, Gaedtuk; Anderson 5150; Geist, 1933, Hultén (1942) also lists a specimen (Geist, 1933) as C C. canadensis ssp. Langsdorffii X C. nutkaensis; I have not seen the specimen. Range: circumpolar, arctic and cool temperate regions. Northern limit: zone 4, reaching zone 3 on arctic coast of the Chuckchi Peninsula. 20. Calamagrostis deschampsioides Trin. Specimens which are best identified as this species were found growing semi- “apc a the sandy shores of sonal er near Gambell and Kialeg EXAMINED: Young 465, Kialegak; 750, 752, 763, 794, Gambell. ae Airing by) Hulk (1942). Range: = species is apparently rare. Its range is poo known; i s to be essentially circumpolar, but very ae ted. Northern limit: said to site Wresgel Island (Hultén, 1962), a lower zone 2 are 21. Noman rie neglecta (Ehrh.) Gaertn., Mey. & soe Uncommon; found in some alpine areas and also sandy shores of small There is a consi rable amount of morphological ciation in the material tested below. So e specim wi n panicles and long awns might be considered to pen P belong to C. kolymaensis K Kom. (cf., Porsild, 1965). The genus Calamagrostis in the Beringean region is so complex and ated known that it seems best to treat it con- sy hanaeged until more adits has been SPECIMENS EXAMINED: Young 171, 299, ‘Savoonga; 564, Gaedtuk; 767, 795, Gambell. No previous reports S Rasp: circumpolar, arctic and cool temperate regions. Northern limit: apparently lower zone 3. 22. Deschampsia caespitosa (L.) Beauv. airly common on dry tundra and alpine areas over the entire island. Deschampsia ae. ery involved complex of wide distribution. Two quite distinct forms are found on St. Lawrence Island. The more common form is rather i into ssp. orientalis Hult. (D. brevifolia of Porsild a rather distinctive ith involute, blui ri ae sone ~ small spikelets is sometimes found. This has been described as D. glauca as D. caespitosa var. glauca (Hartm.) Sam. Variety glauca is - caine as a separate species here, ugh ay change its s e entire complex is in great need ot a — biosystematic study before a “full clarification can be made. a NS EXAMINED: D. caespitosa ssp. orientalis: Young 186, Kookooligit Mca abe: 663, 665, 672, 694, 1414, Boxer Bay; 746, 750x, Gambell; 1341, 1375, Gaedtuk. Geist, 1933, Southwest Cape caespitosa var. glauca: Young 252, Savoonga; 481, ‘ t, 1933. Range: ‘the aespitosa complex is a wide- ecies southern hemisphere. ic- ou occur in the so p Northern limit: zone 1. The ranges of the various segregates of the complex are difficult to discuss, since there is so little agreement on the taxonomy of the group. 38 STEVEN B, YOUNG 23. Trisetum spicatum (L.) Richt. Fairly common in most habitats. All specimens from St. Lawrence are low-grown, have short, broad glumes, and contracted panicles. According to Hultén (1959) they belong to ssp. spicatum, the most arctic form of the T. spicatum com lex. SPECIMENS EXAMINED: Young 119, Tapphook; 229, Savoonga; 413, Kialegak; 537, Siknik; 580, 589, Gaedtuk; 675, Boxer Bay; 798, Gambell. Several other reports. Range: circumpolar arctic and temperate regions. Probably also represented in the southern hemisphere. Northern limit: closely approximates the northern edge of zone 2 throughout its range. 24, Poa arctica R. Br. SPECIMENS EXAMINED: 3 A oe Poovookpuk. Several other reports. Range: (as several poorly defined infraspecific taxa and apomictic groups) circumpolar, arctic-alpine. Northern limit: zone 1. 25. Poa eminens Pres] is species is usually found only in the Elymus zone on the foreshores of eo om I did not collect it on St. Lawrence, nor have I seen any specimens from the island, but Hultén (1942) lists several collected by Geist and Anderson, and it cannot be doubted that the species occurs there. : SPECIMENS ED: none. Range: coasts of the Bering Sea and north Pacific Ocean, southern Hudson Bay and the Gulf of St. Lawrence. This highly disjunct range is nearly identical to that of Senecio pseudo-arnica, another strand plant. Northern limit: not clear, as the range is limited. 26. Poa alpigena (E. Fries ) Lindm. Rare in snow-flushes and other well-watered alpine situations. See P. arctica. SPECIMENS EXAMINED: Young 232x, Savoonga; 646, Boxer Bay. No previous reports. Range: circumpolar, arctic-alpine. Northern limit: zone 1 27. Poa malacantha Kom. (P. Komarovii Roshev. of many authors ) Common on rocky alpine areas and on some old village sites. See P. arctica. a St. Lawrence this is the commonest member of the P. arctica group. All plants whic I have seen are viviparous. SPECIMENS EXAMINED: Young 261, Savoonga; 695, Boxer Bay; 1434, Gambell. VASCULAR FLORA OF ST, LAWRENCE ISLAND 39 Geist, 1933, Poovookpuk. Range: Beringean endemic. Northern _ not clear hectiuse of limited range, but ranges north to Point Barrow, a zone 2 a 28. Poa Lappe: Scribn. & Merr. (P. leptacoma Trin. of some authors ) Ra common on dry tundra and lower alpine slopes. The distinction between this species oe t: Rie gts is not clear. SPE EXA ung 117, 118, Tapphook; 625, 1321, Boxer stk 1456, nee hell. es reportedly pelea by Geist, Anderson (Hultén, 1942). Range: ountainous regions of eastern Asia and western North America. Northern ei not ae but ranges north to ieee Island, a zone 2 area 29. aap fulva ( Trin.) Anderss. Common on the shores al i pools and tundra ponds. rahe a EXAMINED: ung 448, Kialegak; 593, Boxer Bay; 1396, Ga edtuk. Several other reports. ee e: arctic; essentially circumpolar, but absent in most of Greenland and eastern arctic Canada. Northern limit: zo 30. Dupontia Fischeri R. Br. approach ssp. psilosantha. The difference is not clear and may depend partly o habitat and state of development of the 998 There is no reason to vats fing that there are two separate populations on the isla: SPECIMENS EXAMINED: Young 342, No east Cape; 522, Siknik; 678, 728, Boxer Bay; 783, Gambell. a 1933, Boxer Bay. Several other reports. Range: circumpolar, arctic. Northern limit: z [Puccinellia epson (Trin. ) Serib. & Merr.] Reported by Kjellman as Glyceria vilfoidea (Anders.) Th. Fries. The species is not included in the flora of St. Lawrence Island by Hultén (1968a). I prefer to exclude P. phryganodes from the island’s flora until a voucher specimen is foun The species is to be expected on St. Lawrence. 31. Puccinellia Langeana ( Berl.) Geers. nit S rom St. Lawrence apparently do not conform well wi of the subspecies described by S¢rensen (1953) from ee Greenland : SPECIMENS EXAMINED: Young 1448, Gambell. Geist, 1933, Boxer Bay. Anderson 5149, Savoonga. Range: arctic, very disrupted but probably etlly circumpolar. orthern limit: not clear, but reaches zone 2 at Point Barrow and Wr angel Island. [Puccinellia pumila (Vasey) Hitchc.] Hultén (1942) treated the — here considered under P. Langeana as P. mila. 32. Festuca brachyphylla Schult. CG beaches, and alpin : a on backshores, Aap Tapphooks pang s i 588, 1393, Gaedtuk; 688, Boxer Bay; 751, eckall Several other r . Range: umpolar, arctic-alpine. eports Northern limit: northern zone 2, reaching zone 1 at Elif Rees Island. ( Festuca rubra L.) feos Vogt Pes ani that this species was collected at ca by J: P- nee © pre widely introduced lowland form of F. rubra was shown on a dot no na Fle Hise). It seems probable that ees species was acuseien at Sevoout at the Anderson’s visit, and that it has since disappeared. 33. Festuca altaica Trin. A single collection from a rocky streambed in dry tundra seems best identified as this species, although the awns on the lemma arise from a lacerate apex which appears similar to that of some species of Bromus. In other characters, the specimens do not resemble any species of Bromus known to occur in Alaska. 40 STEVEN B. YOUNG SPECIMENS EXAMINED: Young 1397, Gaedtuk. No previous reports. Range: eastern Asia ~ western North America, with outlying stations in eastern Canada. Northern limit: z 34. Elymus arenarius L. Most of the specimens from the shores of St. Lawrence can easily be placed in the taxon known as E. arenarius ssp. mollis or E. mollis Trin. SPECIMENS EXAMINED: Young 132, Os ee 345, Northeast Cape; 458, Kialegak; 485, Siknik; 671, Boxer Bay; 729, Gambell. S$ everal other reports. Range: Elymus arenarius sensu lato: essentially circumpolar, but rare along the coast of Siberia. Northern limit: zone 3. CYPERACEAE 35. Eriophorum angustifolium Honck. Abundant in wet tundra and often the major constituent of such ag isc ery 2 also occurs on the island, but I can find no bp ones that more than one population of E. angustifolium is ts os casa in the island’s flor SPECIMENS EXAMINED: Young 146, 150, 246, Gavceigk: 308, Northeast Cape; 656, 680, Boxer he 740x, 782, Gambell. Several other reports. Range: circumpolar, arctic alpine. Northern limit: conforms almost perfectly with the northern boundary one 2. 36. Eriophorum callitrix Cham. ’s type specimen of this species was collected on St. Lawrence Island collected t own vi a ety circumpolar, but ‘with eal icin gt orthern limit: northern zo 37. Eriophorum Scheuchzeri Hoppe ae found once on a sandy backshore, once in a patch of alpine wet tundra. The only pees report of this species on St. Lawrence is by Kjellman (1882); Hultén (1942) doubted this eg as the specimen could not be found. inesctisiiies EXAMINED: Young 492, Siknik; 1373, Gaedtuk. Range: circumpolar, arctic-alpine. Northern limit: northernmost zone 2, reaching zone 1 in Canada and New Siberian Islands. 38. Eriophorum russeolum E. Fries All specimens of this species from St. Lawrence have white bristles. There is a good deal of variation in the material, and it is possible to distinguish both var EXAMINED: ee olbide um: Young 57, Tapphook; 158, — 31, ast Cape; 605, ier Bay; : — Gaedtuk. Subspecies rufesce oung 147, 247, Savoonga; 400, 447, Kialegak. Several other reports. Range: not a: clear VASCULAR FLORA OF ST, LAWRENCE ISLAND Al because of taxonomic difficulties. Apparently nearly na but absent in Greenland. Arctic-alpine. Northern limit: reaches zone 2 in Siber 39. Eriophorum vaginatum L. Rare on St. Lawrence Island. Found at a few scattered hy on dry tund cies dominates the tussock tundra which is so comm n the mainland oe arctic Alaska. The absence of tussock tundra on St. Lawrence is due | to the rarity of E. vaginatum. SPECIMENS EXAMINED: Young 738, Gambell; 1372, Gaedtuk. No previous reports. om nearly circumpolar, but rare in Greenland. Arctic and cool pom uD regions. Northern limit: northern zone 3, reaching southern zone 2 in a few area 40. Kobresia simpliciuscula (Wahlenb.) Mackenzie Found once, on the mugen = a small fresh water kaspfa SPECIMENS EXAMINED ung 145, Tapphook. No previous reports. Range: arctic- alpine. Essentially praia but ‘fragmented in Eurasia. Northern limit: zone 3, with a few stations in zone [Kobresia myosuroides ( Vill. ) Fieri and Paol.] Reportedly collected by Eschscholtz aipsiones age 1900). Bo: species is = confused with Carex glareosa, which is common . Lawrence. I have never collected K. myosuroides there and so prefer to sstusls ‘the i eckes from the flora until its presence can be supported by a modern specimen 41. Carex Jacobi-peteri Hult. Found several times at the edges of small tundra pools on the south side of the island. These are apparently the first collections of this rather distinctive species outside the type geen at Cape Prince of Wales SPECIMENS EXAMINED: Young 626, 1335, Boxer Bay; 1428, Ataakas Camp. No previous reports Range: see above. Carex scirpoidea M ic Reported from St. Lawrence by Holm (1907) with no specimens cited. : n subspecies which is native to Euro e florets are more loosely arranged on spikes than in most Alaskan specimens, and the lower perigynia are somewhat sha Occasional oa a three stigmas CIMENS EXAM 1417, Booshu Cam mp. No previous reports. Range: bicadty nphiBeringan, rea watt from Alaska and western U.S. to Japan. Also in the Pyrenee and Caucasus Mountains. The species reaches the Arctic only unn. Reportedly collected by Chamisso (Meinshausen, 1900), but this species has not been ronnigt: on St. pion since then. There are no phytogeographical reasons why the species should not occur on St. Lawrence, but since no mo specimens exist it seems “bor to exclude the seaies from the island’s rat 43, Carex woorowin's Schkuhr Of scattered occurrence on drier upland tundra. Carex Lachenalii Ny oy aa ap specimens, SPECIMENS Pipe Young 142, Tapphook; 449, Kialegak; 718, Gambell; 1367, Gaedtuk; 1400 Powooiluk; 1406, Boxer Bay. Geist, 1933, Poovoo kpuk. Range: circum- polar, arctic-alpine. Northern limit: northern zone 3, reaching zone 2 at Wrangel I. 42 STEVEN B, YOUNG 44, Carex glareosa Wahlenb. : Common on wet tundra near the sea, particularly in areas which are subject to normal. SPECIMENS EXAMINED: Young 130, Tapphook; 161, Savoonga; 309x, 325, Northeast Cape; 422, 436, Kialegak; 535, Siknik; 597, 628, 681, Boxer Bay; 739, 740, Gambell Many other reports. Range: circumpolar, arctic-alpine and northern temperate regions. Subspecies stans is the arctic race. Northern limit: follows the northern edge of zone 2. Reaches zone 1 at Elif Ringnes Island in Canada. 46. Carex subspathacea Wormsk. Rather rare along the edges of small lagoons and backshore pools. The species is inconspicuous and may be more commo an ew collections would indicate. PECIMENS EXAMINED: Young 168, Savoonga; 493, 525x, Siknik. Also reported by Rpelvan (1882). Range: circumpolar, arctic. Like other coastal species, apparently not kno they represent an undescribed species. ECIMENS EXAMINED: Young 1422, Kookoolik. Range: coastal areas around the Bering, Chukchi, and Okhotsk Seas. Northern limit: not clear because of limited range. Reaches Point Barrow, in zone 2. 48. Carex stylosa C. A. Mey. 49. Carex podocarpa C. B. Clarke (C. montanensis Bailey ) Found at several small stations in rocky areas near Gaedtuk. When bearing mature spikes, this species is quite distinctive, but specimens collected early in the season are easily mistaken for C. nesophila : Young 571, 581x, 1374, 1380, Gaedtuk. Also reported by Hultén (1942), but not shown as occurring on the island in a later dot map (Hultén, VASCULAR FLORA OF ST. LAWRENCE ISLAND 43 1968a). Range: broadly amphi-Beringean, occurring in the mountains of Eastern Siberia and western North America south to temperate regions. Northern limit: not clear, but reaches Begs Island, zone 2. ommon on a wide v situations. Often found at ah elevations. There is considerable variation in the ane rom St. Lawrence. In some cases the perigynia are indistinctly bitentate at eak, and in a few cases a single stem leaf is present. These specimens are difficult to identify by means of the keys of Mackenzie (1941) ana Hultén (1942, 1968a), but in most Disries they seem to fall well within the range of variation of SPECIMENS EXAMINED: Young 32, 125, Tapphook; 188, 194, 209, Savoonga; 2 282, Northeast Cape; 664, 1342, 1343, Boxer Bay; 756, 759, Gambell; 14 7 oe Camp; 1389, Gaedtuk; 1424, 1426, 1429, near Ataakas oma 1432, ookoolik. ). 51. Carex rariflora (Wahlenb.) J. E. Smith Found once at the edge of a small tundra pool in wet coastal tundra PECIMENS EXAMINED: Young 1420, Kockoolik. Also reportedly ‘collected by R. Rausch and F. H. Fay (J. H. Thomas, P ch communication, 1967). Range: aieunipolar. arctic-alpine. Northern limit: z 52. Carex livida (Wahlenb.) Willd. wo small stations for this species were found, both in wet tundra areas. The St. Lawrence Island specimens are unusually low-grown and stoloniferous. The scales are dark purple, with light green nerves. Similar specimens have been a at Attu Island, and they probably represent a slightly differentiated Beringean of C. livida. The discovery of this rather rare species on St. Lawrence Island pan the range eg several hundred miles. SPECIMENS EXAMINED: Young 148, Savoonga; 657, 661, Bessaem eae No ee a not usually found in arctic areas, and it is almost eae ae arctic and Sanerate Asia. Northern limit: aside from St. Lawrence Island, the few artic stations of this species are in zone 4 53. Carex misandra R. Br. Found in a few scattered stations in mesic tundra SPECIMENS EXAMINED: vice | 1308, Gambell; 1403, near Powooiluk. Also reported by Meinshausen (1900). Range: circumpolar, arctic wi a few alpine stations. Northern limit: closely follows the northern edge of zone 2. (Carex rotundata Wahlen -) eportedly collected by Chamisso and a (Meinshausen, 1900). Ex- cluded from the bok because of lack of recent reports 54. Carex saxatilis L. the south vand central portions a St. Lawrence. All specimens seem to belong to ssp. Setatns EXAMINED: Young 1475, Gaedtuk; 1485, Powooiluk, Also reported by Holm (1907). Range: circumpolar, arctic-alpine. Northern limit: northernmost zone 3, reaching zone 2 at a few stations 55. Carex membranacea Hook. Uncommon on mesic tundra in the southern and central portions of the island. Carex membranacea is often cobeidiercd to be a race of C. saxatilis. On St. Lawrence, the two species occur in the same habitats with no evidence of intergradation, and there seems to be no basis to mgt rae! status as — species. SPECIMENS EXAMINED: gl Boxer Bay; 1402, 1405, near Powooiluk. No other reports in the soe but ln (1968a ) Sie a St. Lawrence Island collection of this species on a dot map. Range: easternmost Siberia and N erican arctic, exclusive of "tr Northern Limit: northern zone 3. 44 STEVEN B. YOUNG JUNCACEAE 56. Juncus castaneus J. E. Smith Abundant on mesic tundra in the central and southern portions of the island. Elsewhere rare and usually confined to specialized habitats such as old village mounds. Occasional specimens are found with little pigment in the inflorescence. Specimens of this type have been called var. pallidus. I doubt that they are of any taxonomic significance. SPECIMENS EXAMINED: Young 563, Gaedtuk; 727, Boxer Bay; 781, Gambell. Also reportedly collected by Anderson (Hultén, 1942). Range: circumpolar, arctic-alpine. Northern limit: closely follows the northern edge of zone 3, with a zone 2 station in north Greenland. 57. Juncus biglumis L. ng. In some respects the above specimens resemble J. Fauriensis Buch. var. kamtchat- censis Buch. from Kamtchatka. However, none of the few available specimens of j. Fauriensis examined have had an inflorescence with onl: florets, and most in- the St. Lawrence specimens seems to be ical of all specimens. The leaves of SPECIMENS EXAMINED: (1) More or less typical L. arcuata: Young 127, Tapphook; 195, Savoonga; 283x, 295, Northeast Cape. (2) Approaching L. confusa, with VASCULAR FLORA OF ST, LAWRENCE ISLAND 45 187, Kookooligit Mountains. Hultén (1943) also repeats several i ot i. 61. Luzula tundricola Gorod. ommon on backshores and dry alpine slopes. Luzula palates was, ri recently, considered to be a variety of L. arctica, from which it differ a number of minor ous ower heads, shorter culms, and broader leaves than L. arctica. Although these differences are relatively minor, they are consistent in our area. There is no doubt that two distinct taxa are involved, although there is some question in my mind as to whether the sare shoe be made at the species level. Luzula arctica sensu lato ther rare on St. Lawrence, and earlier reports of this species undoubtedly are soci nd L. sunente minED: Young 4, Gambell; 103, 121, 122, Tapphook; 283, Northeast Capes 383, Kialegak; 640, 1336, Boxer Bay. Range: broadly amphi-Beringean, ex- ing from Yamal Peninsula to western Mackenzie District. Northern limit: zone 2. 62. Luzula arctica Blytt [Luzula nivalis (Laest.) Beurl.] Rare on St. Lawrence; two stations were found in alpine areas. See L. tundricola. SPECIMENS EXAMINED: Young 788, Gambell; 1404, near Powooiluk. Range: circum- polar, arctic, reaching south of the high arctic only in mountainous regions. Northern limit: found throughout zone 1. 63. Luzula confusa Lindeb. most tundra and backshore areas. In most spaepeeaa the spikes are IMENS EXAMINED: Young 106, Tapphook; 408, Kialegak; 533, 540, Siknik; = 785, "1306, Gambell. Several other reports. Range: circumpolar, arctic, with a stations in alpine areas. Northern limit: found throughout zone 1. 64. Luzula multiflora ( Retz.) Lej. Two small stations were found in _— c tundra on the south side of the island. The specimens are low-grown and delicate, with single flower heads. They belong to ee ‘ead ns race, which Hultén (1968a) calls var . frigi EXAMINED: , Gaedtuk; 1330, Boxer Bay. Also ve aioe Sileinnd tig by "Chatien (Hultén, 1943). Range: circumpolar, low arctic and temperate regions. Northern limit: northern zone 4, reaching zone 3 in Greenland and probably in arctic Siberia LILIACEAE 65. Veratrum album L. A single plant was found growing in mesic tundra along the upper reaches of the Koozaata River. The specimen has a narrow, spike-like inflorescence and long, narrow tals and sepals. The leaves are narrow, acute, and glabrous on both sides; it ohn re belongs to ssp. gamer which is sometimes treated as a distinct species. N EXAMINED: Young 1345, Nuna. No previous reports. Range: a Eurasian 46 STEVEN B. YOUNG species, barely reaching westernmost Alaska. Northern limit: not clear, but apparently reaches zone 3 along the arctic coast of Siberia 66. ft aetcaas serotina (L.) Rchb. mmon to abundant in snow cocbus situations, grassy alpine areas, and mesic tundra Also spits on hummocks of wet tundra. NED: Young 11, Tanplinoks 211, aie 290, Northeast Cape; 365, Kialegak; 704. ae Bay. Several other reports. Ran ge: alpine areas of Europe, Asia, and western North America, also arctic Siberia and Alaska. Northern limit: zone 2. SALICACEAE e genus Salix is a gece ee group, particularly in boreal and arctic regions of western No merica and Eastern Siberia. On St. Lawrence Island it is not as difficult as on the A ides ail , since many of the critical shrubby 67. Salix reticulata L. Common on the lower alpine slopes, occasional on backshores and wet tundra. seis saree oe which participates in the formation of hybrids rarely if at Lawr ie sali — 13, Tapphook; 173, ii 419, Kialegak; 602, circum The most widely distributed of the polar willows. Norther oon it: northern zone 3, 68. opti woh A most alpine areas. Material from the Beringean region is commonly ean under ssp. pseudopolaris, which is sometimes treated as a separate species. The S wrence sland material is — variable, and some of it is probably of hybrid cari One specimen (Young 603) has abnormal, apparently abortive flowers and sc unusual leaves; it is doubtless a hybrid. SPECIMENS EXAMINED: Young 17, Tapphook; ect hte 590, 603, Boxer Bay; 786, Gambell; 1444, Ataakas Camp. Geist, 1933, P vookpuk. Also reported by Kjell- man (1882). peice Arctic Eurasia and Alas ine! to the western Gauatun arctic. Northern limit: zo 69. Salix peop ae undant on most alpine areas. A characteristic species, easily identified by the ein: skelotomised remains of old leaves. The species is seldom involved in hybrids, but see S. i: lia. IMENS EXAMINED: Young 105, ne hook; 270, Fossil River; 284, Northeast Cape; 375, Kialegak; 764, Gambell; 409, 9, 1410, near Powooiluk. The last is an unusually robust specimen with large tae which may be a hybrid. Geist, 1933, Boxer Bay, Poovookpuk, Kangee, “western half.” Several other r reports. Range: i. agit ge mainly confined to Alaska, Yukon, _ i @ rm Siberia. Northern limit: reaches Wieapal Island and Point Barrow, in zon (Salix rotundifolia Trautv. ) VASCULAR FLORA OF ST, LAWRENCE ISLAND 47 Supposedly collected by Chamisso and Eschscholtz (Hultén, 1943). This species is closely related to S. phlebophylla, and intermediates between the two are common (Raup 1959). Two specimens from the Kookooligit Mountains (Young 201; Geist, S risti undifoli on St. Lawrence is not supporte y any modern specimens therefore, and the species is accordingly excluded from the island’s flora. 70. Salix arctica Pall. e most puzzling group of polar willows. In the vicinity of the Bering S S arctica complex is divided into three taxa which are treated as subspecies: ssp arctica, ssp. crassijulis, and ssp. torulosa. Although the differences betwe ic areas have rrow, oblanceolate leaves which Hultén (1968a) considers to be typical of ssp. torulosa. There are number of specimens with abortive, herma- phroditic flowers which r to resemble S. arctica sensu lato most closely but ich appe r which are probably of hybrid origin. As less than half of the S. arctica specimens from St. Lawrence which I have seen can be placed easily in any one subspecies, I have made no attempt to give the subspecies of the specimens in following list. EXAMINED: Young i) Siknik; 558, Gaedtuk; 606, 648, 682, Boxer Bay; 768, 782, Gambell; Mason, July 10, 1931, Aivichtook Lagoon. Geist, 1931, Savoonga; 1933, Poovookpuk, Camp “C. Several reports. Range: nearly circumpolar, somewhat fragmented in the Atlantic regions; arctic. Northern limit: found in most zone 1 areas. 71. Salix fuscescens Anderss. (S. arbutifolia Pall.) Common on hummocks of wet tundra. This species is easily identified because of the presence of a few gland-tipped teeth at the base of the leaf. Occasional specimens wi e€ species with flagelliform branches and the under surfaces in contrast to the leaves of S. fuscencens, which are glabrous on both surfaces. The leaves of dried specimens of S. fuscescens are usually dark brown in color. Point Barrow, a zone 2 area 72. Salix ovalifolia Trautv. between S. ovalifolia and S. arctica; in earlier treatments these were considered under S$. glacialis. Saint Lawrence Island lies in the middle of the zone of contact 48 STEVEN B. YOUNG ene Hultén’s (1968a) S. ovalifolia — S. cyclophylla. Saint Lawrence speci- of this complex are exce ae its riable, — if one had access to a limited correlations of characters. Therefore, I must conclude that only a single taxon is involved. Tolmatchev (1966b) reaches the same conclusion with reaped to eastern y gct ae members of the S. bia Nir complex. PECIMENS EXAMINED: Young 22, 24, 141, Tapphook; 155, 167, Savoonga; 418, Kialopak: 530, 534, Siknik. Mason 6101, Aivichtook L Lagoon. Geist, 1933, Savoonga. Several other reports. Range: difficult to determine because of taxonomic confusion. The S. ovalifolia complex, including S. obulifolia: “s, cyclophylla, and S. stolonifera sensu Hultén (1968a) is found along the entire coast of Alaska and along the coast i Sera Siberia. Northern limit: reaches the vicinity of Point Barrow, a zone (Salis ‘elacialis Anderss. ) Considered as a hybrid between S. ovalifolia and S. arctica. I have examined one specimen (Young 155, Savoonga) which might be this hybrid. 78. Salix ee. Anderss. was collected in a riparian gravel situation in company with S. pulchra, and it is similar in — to that species. It is rn ad that the latter specimen may represent a <> Ichr SP Ns iesiiedons: Young 94 Kookooliktook River; 362, Kialegak. Several other sce ig man amphi-Beringean, generally confined to mountainous areas. Northern limit: ae Wrangel Island, a zone 2 area 74. Salix pulchra Cham. Common to abundant on wet tundra and alpine areas where there is sufficient — ~ found in riparian gravel where it may sae a height of nearly two feet. S EXAMINED: Young 23, 56, 86, 87, Tapphook and Kookooliktook soit 154, Buvcbiges 279, Northeast Cape; 508, S Siknik. Geist, 1933, “western half,” P “C.” Several other — Range: arctic Siberia and northwestern North aaa Northern limit: zon BETULACEAE 75. Betula nana L. Rare on St. Lawrence, although abundant on the Alaskan mainland, where it an important constituent of the vegetation of shrubby tundra. No two authors agree on the taxonomy of this complex group; I follow Hultén (1968a) in con- sidering all specimens from coastal regions of arctic Alaska as ssp. exilis. SPECIMENS EXAMINED: Young 309, Northeast Cape; 380, Kialegak; oe Gaedtuk Also ee. ot by Coville and Kearney (Hultén 1944). e: Betula cumpolar, arctic-alpine. Northern limit: bak ion the ine ape edge KE zone ao POLYGONACEAE 76. Koenigia islandice im Locally common hemeral pools, puddles and Bi ts, particularly in water- fowl wl nesting areas and near old village sites. Appe somewhat nitrophilous. S EXAMINED: Young 237, Savoonga; O73, nS Ba ri Kookoolik. es ge other reports. Range: circ cumpolar, 673, B . Appears hs co be somewhat VASCULAR FLORA OF ST, LAWRENCE ISLAND 49 fragmented and probably eee somewhat in the course of ath since the plant is an annual. Northern limit: zone 3, oe reaching zone 2. 77. Rumex gtaminifolius’ Lamb. clear, ‘but ue preneed Island, a zone 2 are 78. Rumex acetosa L. A few specimens were collected on the banks of the upper reaches of the oozaata River. The specimens appear to be the Hig s0t artic-montane form which Hultén (1968a) treats as ssp. alpestris, and which ewer 34 to the forms treated as ssp. lapponicus and ssp. pseudoxyria by Tolmatchev (1966b PECIMENS EXAMINED: Young 1349, Nuna. Also reportedly collected by Geist (Hultén 1944). Range: the nominate ———* is widely distributed throughout the world, often occurring as an introduced weed. Subspecies alpestris ranges across Eurasia in arctic and alpine regions, rea ing Alaska an e northern Rock Mountains. Northern limit: —— follows northern edge of zone 3 in Siberia; reaches Wrangel Island, a zone 2 area 79. Rumex arcticus Trautv. mmon or abundant on backshores and at the edges of small ponds and puddles on wet tundra. peu on moist alpine slopes PECIMENS EXAMINED: Young 16, T. apphooks 166, Savoonga; 323, agra — 434, Kialegak; 624, Bouse Bay; 771, Gambell. Several other reports. Ran Siberia and northwestern North oe Northern limit: reaches at least to piles me 2. a Oxyria digyna (L.) Hill Common to abundant on rocky str anks, alpine areas, and hummocks on wet tundra. The raw foliage is edible; it rer a pleasant, sour flavor _ makes a gi thirst quencher. a is particularly usef on St. Lawrence Island, since most oud spt to haeaing: mare ein ae S EXAMIN oung 12, — 185, Savoonga; 291, PS iemae Cape; 379, ‘dene 607, sy Bay; 777, Gambell. Many other reports. Range: circum- polar, ar arctic-alpine. One of the most ubiquitous arctic plants. Northern limit: stone throughout zone 1. 81. richer viviparum L. re- producin ing populations of P. vivipara are not known, it seems unlikely that the species tae —e any hybri rids. Young 355, Northeast Cape; 339, 445, Kialegak; 502, Siknik; 578. 509, B — mee 734, Gambell. Anderson 5153b, Savoonga. Also reported by Kjellman (1882). ae: circumpolar, arctic-alpine. No rthern limit: reaches the northern edge of zone 2 82. Polygonum bistorta L Rare on St. Lawrence; a few stunted specimens were collected in alpine seepage areas, often t ation. CIMENS mart ot oung 39, Tapphook; — Kialegak; 693, Boxer ee big other reports. Range: widely distributed im arctic and alpine regions 0 nese Alaska oi extreme northeastern Cainde. Northern limit: barely Fa e 2. 50 STEVEN B. YOUNG PORTULACACEAE 83. Claytonia acutifolia Pall. Unc n in snow patches and iba seepage areas. The St. Lawrence psi material is variable. The majority of specimens belong to the form treated as graminifolia by Hultén (1968b), ys coe Hinges more nearly approach SP acutifolia. Since the variation between thes forms appears to be continuous concur with Hultén (1968b) that they raerrg be considered fees the same Nes However, Davis (1966) and Tolmatchev (1966b) treat the two forms as distinct s ae EXAMINED: Young 619, Boxer Bay; 773, Gambell. Mason 6104, Aivi- nats sg abig Range: arctic and alpine regions of eastern Siberia and Alaska. reaches zone 2 at Wrangel Island. (Cc laytonia am .) This species has been reported twice from St. Lawrence. Hultén (1944) mentions a specimen supposedly collected by Haley in 1926. As mentioned, there is some question as to the reliability of the collection location of Haley’s labels. Davis (1966) identified a specimen of Anderson’s (3669b, ISU) as C. tuberosa. As Hultén (1944) C. tuberosa. Therefore, I conclude that the species does not occur on the island or is extremely rare. It is excluded from the flora until its occurrence on the island can be substantiated. 84. Claytonia arctica Adams es once, ee on a barren cinder cone at the edge of the ea vn SPECIMENS EXAM : Young 1430, Ataakas Camp. a previous repor ange: woctie aa Siber ca the islands of the Bering Sea. Not yet known to occur on the mainland of fy genes 1966). Northern limit: reaches Wrangel Island, in zone 2. 85. Claytonia sarmentosa C. A. Mey. Common to abundant on old village sites, bird cliffs. Less common on hummocks of wet tundra and snow Sieg on alpine sl] SPECIMENS EXAMINED: Young 64, 128, Tapphook; 159, Savoonga; 293, 336, North- east mad 439, Risleale 494, Siknik; 634, Boxer Bay. Several other reports. Range: on, and a few stations in eastern Siberia. Northern limit: not clear, sora zone 3, 86. a fontana L. nal on bare soil on wet areas, particularly in old villa age sites and area where ‘waterfowl congregate. Often associated with Koenigia islandica, the only other annual native to St. Lawrence. arectiaain EXAMINED: Young 138, Tapphook; 169x, Savoonga; 736x, Gambell. Also reportedly collected by Anderson ( Hultén 1944). Range: circumpolar, but re fragmented; arctic and temperate re egions, including stations in the southern hem. sphere. Northern limit: reaches zone 3 in some areas CARYOPHYLLACEAE 87. Stellaria humifusa Rottb. Common on backshores and near lagoons. Occasionally found on foreshores. SPECIMENS EXAMINED: You ng ih Tapphoook; 341, 353, Northeast Cape; 736, 737, Gambell. Several other reports. Range: circumpolar, mostly in arctic, but eines -_ the coast to some temperate Seoul: Northern limit: zone 2, reaching zone in couple of stations. 88. Stellaria crassifolia Ehrh. ional in ephemeral pools and puddles, bare soil areas, sandy shores of small lakes, and particularly on river bars subject to occasional flooding. Specimens with VASCULAR FLORA OF ST. LAWRENCE ISLAND Bi mature capsules were not collected. One or two of the specimens listed under S. humifusa may belong to S. crassifolia. SPECIMENS EXAMINED: Young 754, ain 1384, Gaedtuk. Also reportedly collected by Anderson (Hultén 1944). Range: circumpolar, somewhat fragmented, arctic-alpine. Northern limit: zone 3, reaching zone 2 at Point Barrow 89. Stellaria Edwardsii R. Br. (S. ciliatosepala Trautv. ) Rather rare o we omimge rocky stream banks, and ravines in raised beaches. All St. Lawrence specimens of the difficult S. longipes complex are best identified as S. Edwardsii, although “tie ciliated margins of the sepals are not always particularly evident. SPECIMENS EXAMINED: Young 227, Savoonga; 432, Kialegak; 541, Siknik; 1319, Boxer Bay; 789x, 1304, Gambell. No previous reports. Range: circumpolar, arctic. orthern limit: zone 1. 90. Cerastium Beeringianum Cham. and Schlecht. mon on backshores, along stream banks and other sandy areas. Occasional on drier yaaa slopes. The material from St. Lawrence is extremely variable in terms of commonly foun ' on shore areas, while var. Beanies is more common . stream beds and alpine areas. The distinction between C- iain var. gran PECIMENS EXAMINED: vat. ayaa Young 235, 1447, Savoonga; 431, Kialegak; 491, Siknik; 1438, Ataakas Camp. Variety grandiflorum: Young 289, North- other reports. Range: arctic Siberia, Alaska, and Canada, south in mountainous areas. Apparently intergrades with other members of the C. aie complex in areas of contact, and the exact range is difficult to hee Northern limit: members of e C. alpinum complex reach the a limit of land in all parts of the arctic. Since there are no zone 1 areas within the main part of the eae of C. Beeringianum, 91. Sagina intermedia Fenzl. Cc m backshores, at ey of lagoons, and on old house and village sites. Sp aceolly somewhat nitrophi SPECIMENS EXAMINED: You He "I 39, Tapphook; 236, Savoonga; He Latta Cape; 452, so 544, Siknik; 668, Boxer Bay. Other reports. Range: circumpolar, arctic. Northern limit: reaches zone 1 on Franz Josef Land aed New Bibatieon Island. 92. Minuartia macrocarpa (Pursh) Ostenf. ccasional on most of the drier areas of the island. The specimens treated here as M. macrocarpa all have aed broad — with — or more nerves, and usually . Und mm long, but the old capsules are ge and often sonaigs ane so that the large ones are sometimes of no use in identiiying & species. Seeg igi are — loosely cespitose or trailin 3 thin, semi-wood may or may not be prese PECIME S EXAMINED: ely BLT aaa el , Fossil River 511, Siknik; 648, Boxer eg ‘Seened other reports. Range: and alpine regions of Siberia and Alaska. Northern limit: occurs in some zone 2: areas Be STEVEN B. YOUNG 93. Minuartia arctica (Stev.) Aschers. and Graebn. Occasional, sometimes common on backshores, fell-fields, rocky alpine areas, and other well-drained habitats. This is a variable and difficult species which grades toward M. macrocarpa on one hand and M. obtusiloba on the other. I have placed all speci- mens with involute, single-nerved or nerveless leaves in M. arctica, with the exception of a single specimen treated under M. obtusiloba. Most specimens considered under M. rhegate are loosely cespitose and are herbaceous, although some renee may have a woody taproot. In most specimens the capsule is 5-8 mm long, but a few individuals which appear to be intermediates between M. arctica ae M. macrocarpa may have capsules up to 10 mm long. SPECIMENS EXAMINED: Young 192, Savoonga; 288, Northeast Cape; 572, 1368, Gaedtuk; 702, 720, Boxer Bay. Geist, 1933, Boxer Bay. Range: arctic and alpine areas in Siberia and Alaska. Northern limit: not clear; reaches at least to northern zone 3. 94. Minuartia obtusiloba (Rydb.) House Found once on a dry sea cliff near Boxer Bay. This species is similar to M. arctica, but it has a densely cespitose habit, a thick, woody taproot, somewhat woody branches, and short, imbricated leaves which are sometimes ciliated nearly to the apex. Some of the specimens treated under M. arctica approach M. obtusiloba in terms of growth habit. SPECIMENS EXAMINED: Young 647, Boxer Bay. No date reports. Range: the ringean regions and the mountains of western North America. A closely related or identical species occurs in the Gulf of St. Lawrence einai in eastern Canada [M. marcescens ( Fern.) House]. 95. Honckenya peploides (L.) Ehrh. mmon on foreshores. Usually associated with Mertensia maritima, both species being found to the seaward of the Elymus zone. All St. Lawrence specimens are of grea of Amt habit. S EXAMINED: Young 129, Tapphook; 344, Northeast Cape; 462, Kialegak; 495, “Siknik; 653, Boxer Bay. Several other reports. Range: circumpolar, but in common with most strand species rare along the arctic coast of Siberia. Northern limit: zone 3. 96. Wilhelmsia physodes ( Fisch.) McNeill —— in sandy stream beds, on solifluction lobes, and = raised beaches. : Young 584, Gaedtuk; 726, 743, Gambell. Several other reports Range: easternmost Siberia and northwestern North re Northern limit: ne 3. 97. Silene acaulis L. Occasional on rocky a ——. particularly small alpine stream beds. SPECIMENS EXAMINED: Young 176, Savoonga; 442, Kialegak; 532x, Siknik. Several other reports. Range: ce and alpine areas of North America and Europe. Hardly known from Siberia. Northern limit: reaches zone 1 in Franz Josef Lan 98. Melandrium apetalum (L.) Fenzl — airly common on moist tundra, snow patches, and lower alpine slopes. The my of the arctic members of the genus Melandrium is still not clearly understood VASCULAR FLORA OF ST. LAWRENCE ISLAND 53 the capsule to appear ten-toothed. The mature seeds are about 2 mm in diameter, with a broad wing. Some of the specimens treated here as M. apetalum c some justification, be identified as M. macrospermum, a rare and somewhat indistinct species found only in extreme northwestern North America. SPECIMENS EXAMINED: Young 104, Tapphook; 251, Savoonga; 562, Gaedtuk; 1317, xer Bay. Several other reports. Range: circum lar, arctic-alpine. Northern limit: closely follows the northern edge of zone 2. Reaches zone 1 in Severnaya Zemlya according to Hultén (1968a). 99. Melandrium affine J. Vahl petals as a separate species, M. Soczavaenum Schischk. Since the total range of variation between the two yen can sometimes be ound on a few square feet of of M. SPECIMENS EXAMINED: = ome ons 421, en "507, Siknik; 698, Boxer Bay. ge of zo RANUNCULACEAE 100. Caltha palustris L. Common in shallow pools on backshores and raised beaches, occasional on wet — Saint Lawrence specimens elong to var. arctica ECIMENS EXAMINED: Young 58, 108, Tapphook; 149, ripening 289, Northeast Gis. 417, Kialegak; 516, Siknik; 697, Boxer Bay. Several other reports. Range: ret -cireumpolar, absent in Greenland. Arctic and cool temperate regions. Northern ar. arctica reaches northern z 101. Delphinium brachycentrum L ne Found on the sides of several steep-sided valleys near Southwest Cape. Usually ows on scree slopes or on rock ou pie ECIMENS EX ccm Young ‘oe kK Kangee. Geist, 1933, Poovookpuk. Range mountainous areas in northwestern North America and ‘northeastern Siberia. rccthees limit: not clear, but probably zone 3. 102. Aconitum delphinifolium DC. Abundant on mesic tundra and backshores in the vicinity of ancient or modern human habitations; rare in alpine snow flushes. Hultén (1968a) indicates that both ssp. paradoxicum and ssp. delphinifolium occur on St. Lawrence ens which I have seen have cue low gro gle flower typical of ss orabeeec a SPECIMENS EXAMINED: Young 216, Savoonga; 632, Boxer Bay; 730, Gam Several other r reports. Range: northeastern Siberia and northwestern North America. Northern limit: each Wrangel Island, in zone 103. Anemone narcissiflora L. ores and moist tundra, — in lower alpine areas. All St. mmon on backsho: te I bel t erence Island oo san 10, ee bell; “33, Tapphook; ae Savoonga; 370, Kialegak; 617, Boxer Bay; 1364, Gaedtuk. Sev eral other reports. Range: many dis- junct cake in mountainous ee and Asia, some stations in western North America south of Alaska. she reaches the arctic outside our area. Northern limit: reaching’ Weibel Island, zone 104. Anemone Richardsonii 04 Common along stream banks, on solifluction lobes, and in other mesic tundra Situations. SPECIMENS EXAMINED: Young 84, Tapphook; 243, Savoonga; 367, Kialegak; A gean distri Boxer Bay. Other reports. Range: essentially an expanded amphi-Beringe 54 STEVEN B. YOUNG tion, with a few stations as far east as eastern Canada and Greenland. Northern limit: zone 3. 105. Ranunculus aquatilis L. Found in small streamside pools near Gaedtuk. I am unable to equate the Lawrence specimens with any of the North American varieties of R. aquatilis ia cussed by Benson (1948). The most striking character of the St. Lawrence specimens is the large fruiting head, each containing 30 to 50 achenes which are approximately 2 mm long in the mature condition, and hi idulous along the suture. These numerous than is usual in this form. I am inclined to consider the St. Lawrence material as being a somewhat abertant form of var. capillaceus, but if more material were available it is ona possible that the creation of a new variety would be PECIME g Range aquatilis sensu lato): eich se widely distributed in both temperate a arctic regions, and reaching the southern hemisphere. Northern limit: appears to follow fairly closely along the northern boundary of zone 3, with some stations in zone 106. Ranunculus Gmelini DC. Found in a few shallow puddles near Gaedtuk. The St. Lawrence specimens appear to be intermediate between ssp. Gmelini and te poaial (Richards.) Hult. SPECIMENS EXAMINED: _— ng 1355, Gae . No previous reports. Range: nearly circumpolar, but not known in the arctic pein bordering th e Atlantic Ocean; arctic, alpine, and cool Ricimcate regions. Northern limit: not prot some stations as far north as zone 2. 107. anne: a haa Rottb. These oe appar oo are ssp. sey oreus. Pie specimen vicinity of Northeast Cape (Young 354) was collected in flo ower. This et cimen en has ‘ dling main range is in ee Siberia SPECIMENS EXA : Young 143, Tapphook; 354, Northeast Cape; 455, Kialegak; 527, Siknik. ae reports. bea circumpolar, arctic-alpine. Northern limit: northern zone 2, a few stations in z 108. Ranunculus Pallasii Schlecht. casional in stagnant tundra and isin pools. Saint Lawrence specimens are of rather gerne habit, and the leaves are entire or only slightly lobed. SPECIMEN MINED: Young 321, Rlacthcast Cape; 386, Kialegak; 489, Siknik; 601, — Bay. Coville & Kearney 1971, Northeast Cape. Also reported by Kjellman (1882). e: more or less circumpolar, but in several disjunct areas. Almost entirely con- to arctic regions. Northern limit: zone 3. 109. Reaping glacialis L. somewhat more variation in Beringean populations. Those of St. Lawrence are of comparatively robust — ha gues densely ist and have leaves some- what less ely lok VASCULAR FLORA OF ST, LAWRENCE ISLAND a 110. Ranunculus reptans L. (R. flammula L. var. filiformis (Michx.) Hook. tise growing in shallow streamside pools near Gaedtuk; associated with R. Gmelin SPECIMENS EXAMINED: Young 1387, Gaedtuk. No previous reports. Range: circum- polar; arctic and cool temperate regions. Northern limit: zone 4, reaching zone 3 in a few areas 111. Saliaeigs nivalis L. mon in most alpine and mesic tundra situations. Ranunculus nivalis is closely elated to R. Duleluitene Soledad nd intermediates are not uncommon (Benson 1948, 1954). The two species are distinguished by the hairy receptable and more robust L ; CIMENS EXAMINED: Young 2, Gambell; 395, 453, Kialegak; 621, Boxer Bay; 778, pean, Several other reports. Range: gine hardly arse south of the high arctic. Northern limit: northern zone 2, reaching zone 1 in some areas. 112. Ranunculus sulphureus Soland. Occasional on cea apparently prefers somewhat drier conditions than R. nivalis. See under that S. SPECIMENS EX lana: Young 20, Tapphook; 240, pigeece 280, Northeast Cape. Also reportedly collected by Haley (Hultén, 1944). As noted, there is some doubt about the accuracy of the labeling of soap eee Range: circumpolar, mainly eneaed to the high arctic. Northern limit: zo 113. Ranunculus pygmaeus Wahlenb. Common in alpine areas and near small tundra pools. oon abundant at old village ee. near bird cliffs, and in other areas of rich, moist s SPECIMENS EXAMINED: Young 6, Gambell; 78, Tapphook; 233, Savoonga; ale Siknik; 629, Boxer Bay. Several other reports. pages circu eer arctic, with a few alpine stations in both hemispheres. Northern limit: z sparse than in either of the above es and the sepals th themselves are very delicate, as seems to be pe oe erst of R. pedatifidus. bios peor characters of the above fis = within the range of variation of R. pedatifidus, an extremely variable spec specimens ay snantioney above could be a hybrid between R. pedatifidus and R. a A or R. n SPE aicroe EXAMINED ag ae 107, ila scuaags No previous reports. Range: circum- polar, arctic-alpine. Northern limit: lower zone ( ae repens Benson regards Mason 6094, from Savoonga as a specimen of this species, which is usually an introduced weed, having originated in temperate regions. See R. Turneri. 115. Ranunculus Turneri Greene There is considerable confusion regarding the taxon (or taxa) here er as R. Turneri. The only previous report of R. Setter from St. Lawrence is by Hultén (1944), who _— Mason 6094, are as this species. Benson (1948) regards the same specimen as being the typical form of R. repens. This identification seems arr ipned for ue reasons, the most important being that R. repens is generally CO) cba mperate regions. 56 STEVEN B. YOUNG which may be nearly 3 cm in diameter. The petals are bright wer a ons very broad, often somewhat emarginate, and with a translucent area at the . The : eh : A second group of specimens aah her 1345) was collected on a gravel bar in small river near Gaedtuk. These specimens are tall and robust, reaching a height of 3 to 4 dm. The flowers are somewhat smaller than those of the specimens listed above, and seldom more than 2 cm in diameter. The petals are comparatively narrow, . The not glossy, and have a well-developed triangular nectary fla achenes are about 3 mm long, with a curved, hooked beak about 1 mm long. — pea in this collection appear to be an almost perfect match for R. acriformis A. Gra species ary © known from the Rocky Mountains in northern United States. ‘The toed beak of the one seems to be particularly characteristic of this specie: see only one specimen of R. Turneri identified ed nson (Townsend, 1886, ‘Fall Island); it is quite similar to my 1345 mentioned soles pear _ owers are somewhat larger. The nectary flaps in Townsend’s specim large, a character which should, according to the key given by Benson (1948) epee it from R. Turneri. It appears that, in a few scattered areas of the western American arctic, pe aR of the R. occidentalis complex have persisted in situ during the last glacial maximu These relict populations are rare, and they consist of relatively few individuals. During the period of time that they were isolated from the main body of the R. occidentalis group, they “steskiny tem a inking amount of morphological aprmg<* There is little chance of gene interchange between the relict populations in the north. The name R. Turneri, oe covers a group of populations which are widely disjunct af are probably not much more closely related to each other than they are to some of the more southern populations of the R. occidentalis group. Apparently one or more of these populations have persisted on St. Lawrence, and a nonetendl from my two collections, as well as the specimen of Mason belong to these ti group with specimens available. Therefore, I consider 7 specimens of this ‘eo Brow St conaran er R. Turneri, although it is doubtful at this is a ne taxonomic entity. A case could be made for coe 116. Thalictrum a L. kioonete in moist alpine areas and along some streambanks and solifluction lobes. Young 112, Tapphook; 576, Gaedtuk. Also reportedly ciliate by Masiei ( Hultén 1944). Range: essentially circumpolar, but consisting of many disjunct populations throughout arctic and alpine regions of the northern hemisphere. Northern limit: zone 3, reaching zone 2 at Wrangel Island. PAPAVERACEAE 117. Papaver Macounii Greene Occasional, most commonly found on moist igi slopes and on solifluction lobes. t n th they can be distinguished a Ma and usually are found on differing habitats. The group of specimens here treated as P. Macounii have elongated capsules with the stigmatic disk more or less conical. The he are grey-green, and most of the vegative parts of the plant are are sparsely covered with thick, brown hairs. The al : group of specimens. SPECIMENS EXAMINED: Young 42, Tapphook; 178, Kookooligit Mountains; 800, VASCULAR FLORA OF ST. LAWRENCE ISLAND 57 ets 1329, Boxer Bay; ne Ataakas Camp. Several other reports. Range: not ar, apparently confined to the Beringean region. Northern limit: not clear, but Oey related species are a c oughout the arctic, ‘ide ting all of zone 1. considerably from the gic safeties 9 under P. Macounii. The major ifference is in the f of the capsule; the specimens listed below have a nearly spherical us appea’ green in color and the pubescence is usually more dense than in P. Macounii. It is probably an unusually small specimen of suite orm discussed here which Hultén section ms as P. alaskanum from St. Lawre C NED: Young 198, Keokooligit Mountains; 545, barrier beach 5 aa west of Siknik; 1435, Ataakas rag Range: not clear. Papaver radicatum sensu lato is a a Sew arctic-alpine specie (Papaver Walpolei A. E. Pors.) Hultén (1945) says ae a single leaf collected at Punuk Islands * cir gies belongs to this species. Papaver Walpolei is distinctive because of i ite flow but I have never observed it growing on either the Punuk Islands or ey ae labelin 119. Corydalis pauciflora (Steph.) Pers. Occasional on moist alpine slopes, solifluction lobes, etc PECIMENS EXAMINED: Young 109, Tapphook; 238, Savoonga; 444, en 587, ste ports Bay. Saal other reports. Range: alpine areas of eastern Asia and no m North America. Northern limit: not clear, reaches zone 3 in several So CRUCIFERAE 120. Cochlearia officinalis L. This species is strongly n — it is abundant and of very rank growth on bird cliffs and old village sites. It mmon on backshores and barrier beaches, but almost unknown on tundra and pin areas. Saint Lawrence specimens vary consider- ably in terms of growth habit, size of leaves, and shape o of the silicle. Most of the may be globose. Hultén (1968a ) believes ~ det subspecies can be distiguished ns this character, but the i imens. 121. Eutrema Edwardsii R. B Occasional; usually pee in szecky alpine areas and particularly along rocky stream penal Ns ep: Young 41, 126, Tapphook; 416, Kialegak; 592, Boxer Bay; 1338, "Gabdtnk. Se Several other reports. Range: circumpolar, mainly arctic, but also found in the mountains of central Asia. Northern limit: zone 2. 122. Cardamine bellidifolia L. Common in virtually all oe — on . thie SPECIMENS EXAMINED: Young 9 li; 48, Te phock: 221, ee Northeast Cape; 722, Boxer Bay; 1370, ‘Gasdhok. Many other reports. Range: circum- polar, arctic-alpine. Northern limit: : found throughout zone 1. 58 STEVEN B. YOUNG 123. Cardamine pratensis L. Common on wet tundra, at the edges of pools in backshore areas and in alpine s. ENS EXAMINED: Young 224, Savoonga; 404, Kialegak; 504, Siknik; 661, Boxer Bay. Several other reports. Range: circumpolar, arctic, alpine, and cool ern it: zone 2. Reportedly collected on St. Lawrence by Haley (Hultén 1945). I have never found this rather characteristic species on the island. The possibility that Haley’s labels are inaccurate has already been mentioned, and it seems doubtful that the species occurs on St. Lawrence. 124. Cardamine microphylla Adams Rare; found twice on wet tundra near Savoonga. ; SPECIMENS EXAMINED: Young 184, near Savoonga; 1443, Kookoolik. No previous reports. Range: found in a few scattered locations in eastern Siberia and northern Alaska. Northern limit: not clear because of restricted range. 125. Cardamine purpurea Cham. and Schlecht. Occasional in alpine seepage areas. All specimens have the deep purple flowers characteristic of the typical form of the species. ai SPECIMENS EXAMINED: Young 45, Tapphook; 709, Boxer Bay. Mason 1931, Aivi- chtook Lagoon. The type specimen was collected on St. Lawrence by Chamisso. Range: known only from central and western Alaska and western Yukon. Northern limit: not clear because of limited range. 126. Draba nivalis Liljebl. A single specimen found along a dry streambank has leaves pubescent with the stellate hairs characteristic of this species. Some of the siliques have a faint pubescence, but otherwise the specimens seem to be typical D. nivalis. SPECIMENS EXAMINED: Young 1369, Gaedtuk. No previous reports. Range: essentially circumpolar, but disrupted in Siberia; zone 2. (Draba pilosa Adams ex DC. ) Hultén (1945) lists a single specimen reportedly collected from St. Lawrence (collector unspecified ) that was identified by Pohle as D. pilosa. This species is similar to D. lactea, and in a group as critical as the genus Draba the report cannot be accepted until it is substantiated by a recent specimen. (Draba pseudopilosa Pohle ) mh Reportedly collected by Chamisso and Eschscholtz (Hultén 1945). This species is also closely related to D: lactea, and the report is doubtful for the same reasons as given under D. pilosa. 127. Draba lactea Adams stellate hairs on the leaves and would be pl in typical D. lactea according to most treatments. A few specimens have the stellate hairs lacking or nearly so, as f typical of D. fladni Abnormal specimens with a few hairs on the upper part © Lawrence. There seems to be no reason to believe that more than a single population of this group exists on the island. SPECIMENS EXAMINED: Young 596, Kongee; 723, 1314, 1334, Boxer Bay; 1380, Gaedtuk. Also reportedly collected by Geist at Savoonga (Hultén 1945). Range: circumpolar, arctic, zone 2. reaching zone 1 in Canada. is W Dr ni ‘ Hultén (1968a) shows a station for this species near Savoonga. See D. lactea. 128. Draba alpina L. Found at a few scattered stations in barren alpine areas. Common only in glacial cirques near Boxer Bay. The specimens treated here as D. alpina are low-grown and VASCULAR FLORA OF ST. LAWRENCE ISLAND 59 delicate; the siliques are glabrous or with a few simple hairs on the margin. The flowers are brilliant ere ye wy SPEC INED: Young 205, Atuk Mtn.; 1322, Boxer Bay; 1414, Murphy River May also have Mace ete by pS ahate and Eschscholtz (Hultén 1945). Range: circumpolar, zo 129, Draba macrocarpa Adams ( D. Bellii Holm. ) Found at a single large station in barren hills near Boxer Bay. Differs from D. alpina, to which it is closely eistall: in its slightly more robust growth habit and pubescent siliques. ENS EXAMINED: ee 1323, Boxer Bay. No previous reports. Range: es- sentially circumpolar, zone 1. 130. Draba hirta L. (D. Bees Pursh. she Common near old village sites near Gambell, one station also found on a rocky stream bank on the south side of pa Similar se D. bo ae but usually larger, more isi — bisa only stellate Psa on the flowering st SPECIMENS INED: Young 1377, Gaedtuk; 1451, Cambell Also reportedly eS at Gambell by Chambers (Hultén 1945). Range: circumpolar, arctic; south in central Asia and eastern North America. Northern limit: northern zone 3. 131. Draba borealis DC. Fairly common on backshores and dry tundra at low elevations. There is much variation between ayia: particularly in flower color (which may range ae caulin PECIMENS EXAMINED: Young 5, Gambell; 428, Kialegak; 499x, Siknik; 595, 654, 1320. Boxer Bay; 1420, a Camp. Also reportedly collected by Chamisso and Eschscholtz (Hultén 1945). Range: sight Bathegrec: mainly near the coasts of the Bering and Okhotsk Seas. Northern limit: unclear because of limited range. 132. Braya humilis (C. A. Mey.) Robins. A single station was found in an area somewhat transitional between dry tundra and fell-field. The specime e comparatively large flowers and siliques, over 1 mm broad; according to Bécher (1956) they would p- ar ( Bocher ) Rollins is identification is tentative, however, until y of this complex group can be worked out in greater detail (cf., Abbe, 1948; Rollins, 1953) SPECIMENS oun, , Fossil River. No previous r ange: not 133. Parrya nudicaulis (L.) Regel Fairly common in alpine seepage areas and snow flus SPEC te apne You ee O, 9, Tapphook; 363, eae 683, 715, Boxer Bay. Numerous other reports. Range: from Spitzbergen across arctic and ce ntral Asia to Alaska pa westernmost Canada. Northern limit: zone 2, reaching zone 1 i in Severnaya Zemlya si CRASSULACEAE as Sedum rosea (L.) Scop. Common in most habitats 7B bird cliffs and village sites. fos Sdeiy robust specimens often occur on lava. Saint Lawrence specimens are all purple flowered and belong tg ssp. Gcasuchen poh band nf $ EXAMINED: Young 76, Tapphook; 165, Savoonga; 340, Northeast ray 360, aa 520, Siknik; 618, Boxer Bay. Numerous other reports. Range: except wet tundra and rock deserts. ae penal on 60 STEVEN B. YOUNG entire S. rosea complex is nearly circumpolar, but it is absent from the central Canadian Arctic. Disjunct populations occur in many temperate areas. Subspecies a occurs mainly in eastern Asia and western North America. Northern limit: SAXIFRAGACEAE 135. Saxifraga oppositifolia L. Rare; two stations found on talus slopes in glacial cirques near Boxer Ba SPECIMENS EXAMINED: Young 1312, Boxer Bay. No ai ad reports. Range: circum- polar, arctic south in Se regions. Northern limit: zone 1. 136. Saxifraga Eschscholtzii Sternb. ms si at two stations on rocky outcrops at low elevations. XAMINED: Young 1442, Ataakas Camp. Geist, 1933, Poovookpuk (Oaiveuty of Alaska). eae Beringean and Alaskan endemic. Northern limit not clear because of limited ran ( Saxifraga serphyllifolia se Reportedly collected by Chamisso ore 1945), but Hultén (loc. cit.) suggests that this report may refer to St. Lawrence Bay, on the Chuckhi Peninsula. No modern specimens from St. Lawrence Island are Adan 137. Saxifraga hirculus L. Scattered but locally abundant, particularly near Boxer Bay. Occurs on wet tundra, ~ seepage areas, and on gravel banks of rivers. PECIMENS EXAMINED: Young 75, Tapphook; 222, Savoonga; 429, Kialegak; 636, Boxer shh 774, Gambell. Mason 6092. Geist, 1933. Southwest Cape. Several other rts. Range: circumpolar, arctic-alpine. Northern limit: zone 1. 138. nian flagellaris Willd. r peci santo narrow sepals and f preg a stalked zea They belong ed ssp. fla, i ous. Jan g 466, Invut Mtn.; 1425, Ataakas Camp. Also ign ad by Geist ( Hul ( Hultén 1945). Range: circumpolar, arctic. Northern limit: 139. Saxifraga bronchialis L. Scattered on rocky outcrops at lower elevations, rare on backshores. There is some variation in the specimens listed, but all apparently belong to ssp. Funstonii (Small) Hult. SPECIMENS EXAMINED: Young 199, 206, ahem: 499, Bites at Gaedtuk; 710, Boxer Bay. Geist 1931, Rtas 1933, Boxer Bay. Ran eastern Asia, western North America sieges Rocky Mountains. Northern limit: ara zone 2. 140. Saxifraga as - he cerns ater re eports . Range: eastern “Asia and western North pence Northern it: Zo’ 141. usa spicata D. Don A single station was found along the shores of a cave-in lake near Kialegak. Speci- mens are less high grown than those from central Alaska, but otherwise appear to be VASCULAR FLORA OF ST. LAWRENCE ISLAND 61 ECIMENS EXAMINED: Young 438, Kialegak. Also reportedly collected by Haley; Hultén (1945) doubts this report. Range: endemic to the Yukon River drainage and ering Sea coast of Alaska. Northern limit not clear oe of limited range. 142. Saxifraga cernua L. Common on backshores, village sites and hummocks of wet tundra SPECIMENS EXAMINED: Young 156, Savoonga; 405, Kiale egak; 4 70, Siknik; 635, — Bay; 745, cia Several other reports.. Range: circumpolar, arctic-alpine. Northern limit: zone 1 ( Saxifraga exilis Steph. ) Hultén esse! indicates on a dot map that this species is known to occur on St. Lawrence. I have no information on these collections. Some of the specimens treated here under S. save or S. rivularis might be considered to be S. exilis. 143. Saxifraga nudicaulis D. Don Abundant on wet tundra, wet alpine are SPECIMENS EXAMINED: ab tie 60, 116, Tapphook; 338, Northeast Cape; 612, Boxer Bay. Numerous other reports. Range: endemic to the Bering Strait Region and the shores of the Okhotsk She Northern limit unclear because of restricted range. 144. Saxifraga bracteata D. Don Typical specimens were found only once, on an old village site near ah ae This species is rather doubtfully distinct from S. rivularis, particularly where the tw are sympatric. Some of the specimens treated here as S. rivularis might be identified as S. bracteata. SPECIMENS EXAMINED: Young 170, Savoonga. Several other reports. Range: coastal areas near the Bering and Okhotsk Seas. Northern limit unclear because of restricted range. 145. Saxifraga rivularis L. Ipine areas, sea cliffs, village sites, and wet areas in backshores. Ap- parently somewhat nitrophilous. Specimens from alpine areas are often delicate, strongly pigmented, and erect in growth habit. Those chen other areas are weakly pigmented, = van ae to approach or merge with S. teata. ei SPECIMEN: : Youn be 25, Tapphook; 351, eae ater Sia 472, Siknik; 724, 1413, Atenas =e "776, Gambell. geod other + reports. Range: circumpolar, arctic and a few alpine areas. Neti ern limit: zon 146. oo davurica Willd. Found at a few stations in the Kookooligit Mountains. Specimens are highly variable aa show nearly the complete range of variation between S. zag ica, sensu a and typical S. unalaschcensis Sternb., under which name earlier ns speci are re identified as S. decisis 0: : eenieubs (Engl. and feaiech. ) Hult. The intermediate nature of these specimens suggests that the status of S. unalaschcensis as a full species should be reevaluat SPECIMENS EXAMINED: Young 204, — 1441, Ataakas Camp. Geist, 1933 07 e: eastern Asia and Alaska-Yukon; S ; censis replaces S. davurica in the em — Sea, and the closely slated S. Lyallii Engler occurs in southern Alaska. Yukon ( Saxifraga isscalis py Reportedly collected at Gambell by Chambers (Hultén 1945). Small specimens of S. foliolosa are easily confused with this species. Since I have never found S. nivalis on St. Lawrence and have seen no specimens, I exclude it from the flora. at it ( Saxifraga unalaschcensis Sternb. ) See S. davurica. 62 STEVEN B. YOUNG 147. Saxifraga hieracifolia Waldst. and Kit. Common on hummocks of wet tundra, on backshores, and in wet alpine areas. SPECIMENS EXAMINED: Young 46, 61, Tapphook; 551; Savoonga; 295, Northeast —- spin Kialegak; 609, Boxer Bay. Anderson 3695, Savoonga. Several other reports. Sue zone 2. 148. oe foliolosa R. Br. n hummocks of wet tundra, backshores and in alpine areas. On St. gieidaaen ithe inflorescence pein mainly of bulblets; flowers are rare. PEC EXAMINED: Young 114, Tapphook; 174, 242, Savoonga; 334, Northeast Gane: “71, "Sikaile 655, Boxer Bay; 757, Gambell; 1441, Atanas Camp. Several other reports. Range: circumpolar arctic, with a few alpine stations. Northern limit: zone 2, reaches zone 1 in Franz Josef Land. 149. Chrysosplenium tetrandrum (Lund) Th. Fries Common in old village sites, wet spots on backshores, and at the edges permanent snow patches, where it may be found flowering in late August. Funan S somewhat nitrophilous. PECIMENS EXAMINED: Young 18, Tapphok; 234, Savoonga; 430, Kialegak; 479, Siknik; 796, Gambell. Seed other reports. Range: circumpolar, but rare in Green land and northeastern Canada; arctic. Northern limit: zone 2. 150. pee Ne ee Wrightii Franch. and Sav. SPECIMENS EXAMINED: one a Atuk Mtn.; 1447, Kangee. rae oe ean collected oy Mason (Hultén 1945). Range: Beringean endemic, known only fr easternmost Siberia an aska-Yukon. Northern limit: unclear because ‘of ec lser range, but reaches zone 2 at Wrangel Island. 151. Parnassia Kotzebuei Cham. and Schlecht. Uncommon, usually found in gravel bars, occasional in lower alpine ar SPECIMENS EXAMINED: Young 218, Savoonga; 407, Kialegak; 717, Boxer Bays ea Gaedtuk; 1437, Ataakas Camp. Also reported by Anderson (Hultén 1945). arctic-alpine North America and easternmost Siberia. Northern limit: — att southern edge of zone 3. ROSACEAE (Spiraea Beauverdiana Schneider ) Collected by Chamisso according to Kotzebue (Hultén 1945). This is almost ly a mistake. 152. Rubus chamaemorus L. Fairly common on hummocks in wet tundra areas, but never abundant, as it is on the Alaskan mainland. The natives claim that a good crop of berries occurs only every four to five sai SPEC MINED: Young 71, Ml cep 160, Savoonga; 303, Northeast Cape; sets Siknik; "598, Boxer ‘Bay; 779, Gambell. Se veral other 1 reports. Range: essentially cumpolar, but rare or absent in most of Greenland and northeastern Canada. Nother limit: northern zone 3. 153. Rubus arcticus L. banks on the south side of the island. Se oi this species is rare or absent, with a few stations being found in protected ies and on raised beaches and other mesic tunda situations. Hultén (1968b) has recently united R. stellatus and R. acaulis with . arcticus, according each of the last pi taxa subspecific rank. On St. ee. single stations of R. arcticus (which are probably often single clones, since underground stolons seotly widely ) raglan a range of variation from the typical thats VASCULAR FLORA OF ST, LAWRENCE ISLAND 63 mens with trilobate leaves are found in more exposed situations near the tops of stream banks and gullies, while trifoliolate specimens occur near the lower edges of the colonies. There is much variation in the glands of the sepals. Some specimens have thin, eglandular sepals, while others are densely glandular. There seems to be no correlation of this character with leaf form or other characters, Petals are usually long and narrow, as in ssp. stellatus, but individual specimens may have short, broad petals. I see no evidence that two taxa of R. arcticus occur on St. Lawrence. It appears that, at least in the Bering Sea region, R. arcti more variable than has pre- viously been believed, and it is not possible to decide which of Hultén’s (1968b) subspecies is represented in the area. t is interesting to note that, although R. arcticus goer abundantly on St. wrence, I never found a single fruit. The summer of 1967 was unusually mild, great age. SPECIMENS EXAMINED: Young 330, Northeast Cape; 579, Gaedtuk; 713, Boxer Bay; 1301, 1302, Gambell. No previous reports. Range: nearly circumpolar, not known to occur in Greenland or northeastern Canada. Northern limit: reaches the northern edge of zone 4. 154. Potentilla palustris (L.) Scop. Abundant along the shores of Koozaata River, where it was often observed in wer. Otherwise occasional in small ponds, where flowering specimens were seldom d. SPECIMENS EXAMINED: Young 289, Savoonga; 325, Northeast Cape; 435, Kialegak; 660, Boxer Bay. Several other reports. Range: circumpolar, arctic south to temperate regions. Northern limit: reaches about to the boundary of zone 4-zone 3, with a ) Reportedly collected by Chamisso. Hultén (1946) considers this report doubtful. As there are no specimens of this species known from St. Lawrence, it is excluded 692, Boxer Bay. No previous reports. Range: Scattered stations in the mount: limit: not clear because of limited range, but reaches zone 2 at Wrangel Island. respect to the ternate-leaved species of Potentilla in arctic Alaska is so confusing smaller than is usual in this species. ” SPECIMENS EXAMINED: Young 385, Kialegak; 691, Boxer Bay. Also reportedly collected by Chamisso and by Geist (Hultén 1946). Range: shores of Bering Sea and southern Alaska and British Columbia. Northern limit: not clear because of limited range. 157. Potentilla uniflora Ledeb. A single collection from a rocky alpine situation is best identified as this species. s oy P (1968a) shows a station on St. Lawrence. Range: broadly amphi 64 STEVEN B. YOUNG 158. Potentilla hyparctica Malte The specimens treated here as this species form a reasonably homogeneous group of plants which are of rather erect growth habit, and have hirsute, not tomentose, leaves. This is the commonest Potentilla 0 n St. Lawrence. It is found mainly on rock deserts, dry stream banks, and seadledially on backshores, where it may be rather low-gr Ema es EXAMINED: Young 8, Gambell; 51, a} rr 190, Savoonga; 384, Kialegak; 478, 521, aly 716, 1315, Boxer Bay; 1407, Southwest Cape; 1449, Savoonga. Several other reports are fs Bereey referable to this species. Range: circumpolar, arctic. Northern limit: z ( Potentilla Hookeriana Lehm. ) Hultén (1968a) indicates on a dot map that this species occurs on St. Lawrence Island. I have not seen a specimen from the island which could be referred to this cies. 159. Potentilla Egedii Wormsk. Common along the banks of the oheersinied — near Nuna; otherwise only a few pee Se ssagga found in brackish coastal ar Se AMIN Young 144, Pach em 518, Siknik. sins 160. Geum glaciale Adams Fairly common in high alpine areas in the Kookooligit and Poovoot Ranges. SPEC INED: Young 193, Atuk Mtn.; 1327, Boxer Bay. Geist, 1933, Boxer Bay (University of Alaska). Range: arctic Siberia and Alaska-Yukon. Northern limit: 161. Dryas ssaesigaea Ee saan aig : Young 35, s eppnocls. I > Savoonga; 381, Kialegak; 708, iar Pay: 770, Ganka 1361, Gaedtuk; 5, Kangee. Several other reports Range entially circumpolar, but rare in ae pa where = is aera by D integrifolia, Northern limit: zone 2, reaching zone 1 in the vicinity of T: aimayr 162. Dryas integrifolia M. Vahl A single station found shes the shores of a cave-in lake near Kialegak. PECIMENS EXAMINED: Youn, egak. is undoubtably the same station as that found by Chamisso and Eschechs tz (Hultén 1946). Range: arctic-alpine. — entirely confined to North America. Northern limit: northern boundary of ne 2. LEGUMINOSAE 163. Astragalus umbellatus Bunge Uncommon, usually found on alpine seepage ar BP ssrawanmasdinears ue oe Bet Tepinoks 707, Boxer Bay. aaron 8 6113, Aivi- Lagoon. Also reportedly collected by Geist (Hultén 1946). ge: arctic ean and Alaska- Voken, with a few outlying stations. Northern ke oe ee VASCULAR FLORA OF ST, LAWRENCE ISLAND 65 164, Astragalus alpinus L. Reportedly collected by Mason (Hultén 1947). There is no reason to doubt the authenticity of this report, but I have never collected this species on St. Lawrence. It must be of rare and local occurrence. SPECIMENS EXAMINED: none. Range: arctic-alpine; nearly circumpolar, but rare or absent in Greenland, Spitzbergen and northeastern Canada. Northern limit: zone 2 165. Oxytropis Maydelliana Trautv. Of scattered occurrence on rocky areas around the periphery of the Kookooligit Range. SPECIMENS EXAMINED: Young 1360, Gaedtuk. Also reportedly collected by Mason and by Geist (Hultén 1946). Range: arctic North America and easternmost Siberia. Northern limit: zone 2. 166. Oxytropis nigrescens ( Pall.) Fisch. Fairly common, particularly on fell-fields. The most common form is ssp. bryophila (Greene) Hult., but in the higher mountains, the dwarf ssp. pygmaea ( Pall.) Hult. may be found growing with the larger form. There is some evidence of intergradiation, ut the two forms generally remain distinct. SPECIMENS EXAMINED: (ssp. bryophila) Young 101, Kookooliktook River; 191, Savoonga; 297, Fossil River; 374, Kialegak (ssp. pygmaea). Geist, 1933, Boxer Bay. Mason, July 10, 1931, Aivichtook Lagoon. Several other reports. Range: eastern Siberia and Alaska-Yukon. Northern limit zone 3, reaches zone 2 at Wrangel Island. 167, Hedysarum alpinum L. Uncommon on drier alpine areas at low elevation. SPECIMENS EXAMINED: Young 88, Tapphook; 556, 1376, Gaedtuk. Also reported by Kjellman (1882) under H. obscurum. Range: several large disjunct areas in Siberia and North America. Mainly an alpine species, but reaching the arctic in several areas. Northern limit; not clear, but reaches zone 3 in several places. 168. Lathyrus japonicus Willd. (L. maritimus L.) Occasional in the Elymus zone on foreshores. Specimens from St. Lawrence are all pubescent. They apparently belong to var. aleuticus (Greene) Fern., although there is some question as to whether this is the same taxonomic unit in the Bering Sea region as in the Atlantic region. Two taxa may be involved. SPECIMENS EXAMINED: Young 131, Tapphook; 457, Kialegak; 546, Barrier Beach of Koozaata Lagoon. Geist, 1933, “western half.” Range: essentially circumpolar but, as with other strand species, having large gaps Canada and Siberia. Northern limit: in Beringean region reaches zone 2 at Wrangel Island. In Atlantic region reaches only to southern zone 4. CALLITRICHACEAE 169. Callitriche verna L. not known from elsewhere on ruits with no visible styles. PECIMENS EXAMINED: Young 1421, Savoonga. No previous reports. Range: not entirely clear because of taxonomic problems, but apparently circumpolar in boreal and temperate regions and in the southern part o th limit: zone 4, reaching zone 3 in east and west VIOLACEAE 170. Viola biflora L. A few stations found near snow patches near Gaedtuk. : . » SPECIMENS EXAMINED: Young 552, Gaedtuk. Geist, 1933, “Noong Woak's Camp. Range: disjunct in arctic and alpine regions of Eurasia and western North America. Northern limit: northern zone 4. 66 STEVEN B. YOUNG 171. Viola epipsila Ledeb. n mesic tundra. The St. Lawrence specimens belong to the slightly differ- — = oe known as V. achyrophora Greene. NED: Young 134, Tapphook; 253, Savo oonga. Also reportedly oalees a a eine Mason (Hultén 1946). Range: nearly circum 4 but not own to occur in Greenland and eastern Canada. Northern limit: zon ONAGRACEAE 172. Epilobium angustifolium L. A a small stations found on coastal areas around the periphery of the island. imens were sterile. The individual stations are ener clones developed from sey tapes from the Siberian or Alaskan mainlan IMENS EXAMINED: Young 790, Gambell. No previous reports. Range: circum- sala arctic, boreal, and temperate regions. Northern limit: ing ih about to the boundary between zone 4 and zone 3. 173. Epilobium latifolium L. Common to Sevenient in gravelly stream beds, rare or absent in other habitats. SPECIMENS EXAMINED: Young 93 P Eeckocukieck. River; 239, Savoonga. Also re- po ngs aaa rss Geist (Hultén 1946). Range: circumpolar, arctic-alpine. Northern limit: z 174. Epilobium palustre L. are; found growing with E. anagallidifolium along a few stream banks on the = side of the islan ee ECIMENS EXAMINED: Young 1362, 1386, Gaedtuk. No previous reports. Range: cir econ arctic igs temperate regions. Northern limit: northern edge of zone 4, reaching zone 3 in St. Lawrence and in East Greenland. 175. Epilobium anagallidifolium Lam. Common to abundant on mesic tundra along stream banks on the south side of the island; rare or — elsewhere. The distribution on St. Lawrence is similar to that that of Rubus arc asi NS syne ED: Young 742, 1303, Gambell; 1352, Gaedtuk. No previous reports. Range: arctic-alpine; circumpolar but fragmented, with several large gaps. Northern limit: northern zone 4, reaching zone 3 in several areas HALORAGACEAE 176. Hippuris eee L. Fairly common mall tundra and backshore pools. In some sheltered spots, ene set i. -tetraphylla IMENS Young 248, S avoonga; 324, Northeast Cape; 403, ess 517, ‘Siknik, 747, Gambell Several other reports. Range: circumpolar, arctic south to temperate regions. Northern limit: northern zone 3, with some zone 2 stations. Hultén (1968a) locates a station for this species on St. Lawrence. Individual specimens of H. vulgaris may approach this species. UMBELLIFERAE 177. Ligusticum mutellinoides (Crantz) Willar Occasional in rocky alpine areas and fell-fields. SPECIMENS EXAMINED: Young 100, Tapphook; 273, Fossil River; 570, Gaedtuk; 700, Boxer Bay. No previous reports, but Hultén (1968a) aig a aa for this species on St. Lawrence. Range: several disjunct areas in Eurasi ka, arctic-alpine. sac limit: not clear; reaches zone 3 in St. Lawrence Ry ree Zemlya. VASCULAR FLORA OF ST. LAWRENCE ISLAND 67 178. Conioselinum chinense (L.) BSP. Occasional on barrier beaches on the south side of the island. The entire plant is seldom over 10 cm tall, and the inflorescence is sometimes hardly raised above the 179. Angelica lucida L. Fairly common on barrier beaches on the southern part of the island. Also found in cei near shasta — oung 82, Tapphook; 376, Kialegak; 687, Boxer Bay. Also mebary iain en. Range: not entirely clear because of taxonomic ques- tions, but apparently nearly identical to that of Conioselinum chinense. The ranges of ese two Umbelliferous species are unique. CORNACEAE 180. Cornus suecica L. Occasional on mesic tundra. Usually found in large, isolated patches which may be individual clon ECIME eet MINED: Young 77, Tapphook; cen Northeast Cape; 388, ran 554, Gaedtuk; 772, Gambell. Several other reports. Range: both a -Beringean and amphi-Atlantic, mainly near the coast. Northern limit: northern zon PYROLACEAE 181. Pyrola grandiflora Radius A single specimen was found in an alpine area near Kialegak. SPECIMEN EXAMINED: Young 393, Kialegak. Also reported bes Aor (1882). Range: circumpolar, arctic-alpine. Northern limit: northern zo EMPETRACEAE 182. Empetrum nigrum L. Of scattered occurrence on some backshore and fell-field areas. Never abundant, as on the mainland of Alaska. and seldom if ever sets an abundant crop of fruit. All ie oi EXAMINED: Youn, 34, i dpe 220, Savoonga; 300, Northeast ‘ee ambell. ERICACEAE 183. Ledum decumbens ( Ait.) Lodd. Occasional on epciraag” boulder slopes, and h hummocks of wet tundra. SPECIMENS EXAMINED: Young 99, Tapphook; 302, Northeast Cape; 382, peice arcti 559, Gaedtuk; hs ret Several other reports. Range: circumpolar, Northern limit: z 184. Loiseleuria procumbens (L.) Desv. Seco on fell-fields, ine tundra. CIMENS EXA nid oung 102, Tapphook; 339, Northeast Cape; 391, Kialegak. Fels reportedly setachel . Chambers “ 1947). Range: essentially circum- polar, arctic-alpine. Northern limit: zon 68 STEVEN B. YOUNG 185. Phyllodoce coerulea (L.) Bab. Common to abundant in one small area on the north slope of the Kookooligit Range. SPECIMENS EXAMINED: Young 175, Kookooligit Mtns. No previous — Range: circumpolar, but iaieihicn disrupted; arctic-alpine. Northern limit: zo 186. Cassiope tetragora (L.) D. Don Common, sometimes abundant on most rocky alpine areas. SPECIMENS EXAMINED: Young 37, Tapphook; 189, Savoongs 297, Northeast Cape; “i Kialegak; 600, Boxer Bay. Several other re ports. Range: circumpolar, arctic. Northern limit: zone 2, the only ericaceous species found widely in zone 2. 187. Andromeda polifolia L. mon on wet tundra at one small area near Northeast Cape, otherwise rare or Seent Both Kietionas (1882) and Muir (1918) claim that this species is common on the northwestern portion of the island, probably near Gambell. I have not found SPECIMENS EXAMINED: You ung 326, Northeast Cape. Also collected by Kjellman Range: cy ae arctic and boreal regions. Northern limit: reaches to the notte edge of zone 188. Arctostaphylos alpina (L.) Spreng. Scattered on lower alpine slopes, particularly in a boulder talus. SPECIMENS EXAMINED: Young 38, Tapphook; 329, Northeast Cape; 762, Gambell. aeldney other reports. Range: circumpolar, Aan Northern limit: northern Zon 189. Vaccinium uliginosum Two small stations found on dry tundra. No flowering or fruiting specimens were observe reports. Range: ntunaolee ge ‘and bor ou regions. ‘Northern limit: reaches northern zone 4 in most areas, but to northern zone 3 or even zone 2 in Canada an Greenland. This is appar ently id with the is taxonomy of the group, which is being treated in a separate paper (Young, in press 190. Vaccinium vitis-idaea L. Scattered on hummocks of wet tundra. Most specimens are dwarfed, have few flowers, and do not set fruit heavily. SPECIMENS EXAMINED: Young 52, Tapphook; 264, Savoonga; 305, Northeast Capé; 390, Kialegak; 765, Gambell. Several other reports. Range: essentially circumpolar, arctic and boreal regions. Northern limit: othe zone 3, with a few stations in zone 2, DIAPENSIACEAE 191. Diapensia lapponica L. —" on exposed socky alpine ECIMENS : Young 36, , Tapphook 294, Northeast Cape; 684, Boxer sa S at th everal other reports. Ran oe essenti circumpolar, somewhat disrupted; alpine. Northern limit: zo . sf i 4 PRIMULACEAE 192. Primula nivalis Pall. specimens treated here as P. nivalis =~ P. cena siege ae form a small but extremely difficult group about which no authors agree. The recen’ treatments of Porsild (1965) and Hultén (19684) ac aio ‘all au specimens of VASCULAR FLORA OF ST. LAWRENCE ISLAND 69 a o =I rs S =) Qu oO 4 ir) ’) a Ru ° o 5 [om awd fo. ° 5 n ie} 5 —n cr se : i?) 5 ° ta) — nv 3 ioe) Qu & o % a $9 =] 5 e. 5 cee © =| a amount of variation, most of which is so random that it makes it difficult to delineate subspecific taxa. A final understanding of the group must wait until an intensive biosystematic study has been made. heavily farinose and short and broad, with no rudiments of leaf blades. In the speci- the base. The entire plant is effarinose, except occasionally the inner surfaces of the sepals are farinose. Specimens of this type are normally found on dry tundra, rocky village sites, and in wet alpine areas near permanent snow patches. It sho be mentioned that a large part of the material studied is somewhat intermediate in one or more of the characters mentioned, probably due to hybridization between the two es. ; Porsild (1965) described a new variety of Primula tschuktschorum, var. beringensis from a single collection made at Boxer Bay by Sauer. In one small seepage area at oO although they are not typical specimens of that species. Plants of this type apparently for maintaining a separate variety for them. SPECIMENS bis Asi Youn. 7583, Gaedtuk; 610, Boxer Bay; 803, Gambell. Range: 193. Primula tschuktschorum Kjellm. : Common in most habitats on St. Lawrence. See P. nivalis. SPECIMENS EXAMINED: Young 3, 1457, Gambell; 47, 65, Tapphook; 153, Savoonga; 348, Northeast Cape; 456, Kialegak; 474, Siknik; 620, Boxer Bay. Range: ne endemic, with a few stations in central Alaska and eastern Siberia. Northern limit: no’ clear because of limited range. Common to abundant on backshores and lower alpine areas. Many specimens are slightly farinose on the under sides of the leaves, as in var. ajanensis (E. Busch.) igni i have a so great that it cannot have much significance. Some of the larger specimens hav walk-deveboged basil sheath, similar to that found in P. tschuktschorum, possibly indicating int dation between the two species. “ai tin) Temye-genianien Young 67, Tapphook; 213, Savoonga; 426, na cag 477, Siknik. Many other reports. Range: amphi-Beringean. Northern limit: zone 3. 195. Douglasia ochotensis ( Willd.) Hult. (Androsace ochotensis Willd. ) n in the central portion of the island, both in alpine areas and on backshores, rare 0 ise. SPECIMENS EXAMINED: Young 203, Kookooligit Mtns.; 467, Invut Mtn.; 531, 70 STEVEN B. YOUNG it 690, Boxer Bay. Several other reports. Range: amphi-Beringean, mountains of astern Siberia and Alaska. In central Alaska-Yukon, replaced by D. arctica Hook. D. Gormani Constance. N. gece limit: not clear because of limited range, but known to occur on Wrangel Island, zone 2. 196. Androsace chamaejasme Host Fairly common on the drier alpine areas, s Fiuert ially at lower ow ion SPECIMENS EXAMINED: Young 214, 260, Savoonga; 488, nik; 677, Boxer Bay. Several eats reports. Range: exceptionally fragmented; occurs in many alpine areas a and a North America. Northern limit: not clear, but reaches zone 2 at aaa statio: ( Dodecatheon “re Cham. and Schlecht. ) Reportedly hi by Haley (Hultén 1947). The provenience of this specimen is questioned by Hultén (loc. cit.) for reasons already mentioned, and no other col- lectors have ete the species on St. Lawrence. 197. Trientalis europaea L. Found agen on hummocks of wet tundra at a single statio SPECIMENS EXAMINED: Young 551, Gaedtuk. No prevous enone Range: Eurasia and aioe North America, mainly in boreal regions. Northern limit: lower zone 4, except in the Bering Strait region. PLUMBAGINACEAE 198. sean maritima aaa. ) Wwalld. Acc a flora. Periartedly collected at Garis by Geist wi Hultén 1948). There are n no other reports, and I was unable to find any specimens. It is possible that Geist’s specimen is bm ei as to location SPECIMENS EXAMINED: none. Range: circumpolar, ecg ae and boreal regions. Northern limit: northern zone 3, with some zone 2 stati GENTIANACEAE 199. Gentiana algida Pall. Fairly common on dry, rocky tundra, particularly on the southern and central parts of the island. SPECIMENS EXAM 933, Poovookpuk; also ae by Kjellman feeds ange: fragmented; ae ens of Europe, eastern Eurasia and western North America. Northern limit: not clear, reaches zone 2 in New Siberian Islands. 200. Gentiana glauca Pall, Fairly common on moist tundra, solifluction lobes, and along ae banks. PECIMENS EXAMINED: Young 89, Tapphook; 245, Savoonga; 319, Northeast Cape; 392, Kialegak; 500, Siknik; 591, 719, Boxer Seed 749, Gambell. la other reports. ge: amphi-Beringean. Northern limit: zo 201. Gentiana auriculata Pall. A single station found on a gravel bar near Gaedtuk. The only other Alaskan collection of this species is from Attu Island. SPECIMENS EXAMINED: Young 1390, Gaedtuk. No previous reports. Range: coastal areas of eastern Siberia. Northern limit: not clear because of limited range. POLEMONIACEAE 202. Polemonium boreale Adams ommon on wet tundra, backshores, and lower alpine slopes. In his recent treat- ment of the North American species of Po lemonium, Davidson (1950) placed most St. Lawrence specimens in P. boreale. Hultén (1948, 1968a), on the other hand, VASCULAR FLORA OF ST, LAWRENCE ISLAND 71 treats all specimens as P. acutiflorum Willd. According to the key given by Davidson (loc. cit.) most of the specimens from St. Lawrence that I have examined fall into P. boreale, but certain individuals have at least some of the characters of P. caeruleum ssp. villosum (P. acutiflorum of Hultén). is genus seems to resist all taxonomic attempts to define it. Since I can see no indication whatever that more than one taxon occurs on St. Lawrence, I prefer to treat all specimens under P. boreale until such time as the systematics of Polemonium in Alaska are correctly presented. SPECIMENS EXAMINED: Young 137, Tapphook; 157, Savoonga; 299, Northeast C 409, 424, Kialegak (424 is a white flowered form); 519, Siknik; 622, Boxer Bay. Ge 1933, Poovookpuk. Several other specimens collected by Chambers are listed by Davidson (1950). Range: nearly circumpolar, but absent in northeastern Canada and western Greenland. Northern limit: zone 2. BORAGINACEAE zone 1 in Siberian Islands. 204. Eritrichium Chamissonis DC. Of scattered occurrence on dry, rocky alpine areas and dry tundra. SPECIMENS EXAMINED: Young 263, 1430, Ataakas Camp; 441, Kialegak. Several other reports. Range: coastal areas in the Beringean region. Northern limit: unclear because of limited range. 205. Myosotis alpestris Schmidt : I have never found this species on the island, but it was twice collected by Geist. SPECIMENS EXAMINED: Geist, 1933, Poovookpuk; also reportedly collected by Geist at Atuk Mtn. (Hultén 1949). Range: Eurasia and western North America; arctic- alpine. Northern limit: zone 2. 206. Mertensia maritima (L.) S.F. Gray Fairly common on foreshores, mostly seaward of the Elymus zone. SPECIMENS EXAMINED: Young 135, Tapphook; 268, Savoonga; 343, Northeast Cape; 459, Kialegak; 486, Siknik; 652, Boxer Bay. Several other reports. Range: similar to other strand plants; circumpolar except for a large gap along the coast of Arctic Siberia. Northern limit: northern zone 3. [Mertensia paniculata ( Ait.) D. Don] Reportedly collected by Chamisso; this report is consid (1949). I concur with this, as no modern specimens exist. ered doubtful by Hultén SCROPHULARIACEAE 207. Lagotis glauca Gaertn. Fairly com ine areas. Most specimens have narrow, sharply ae ulated leaves, typical of ssp. minor (Willd.) Hult. The distinction between this n i i wrence specimens. SPECIMENS EXAMINED: 43, 110, Tapphook; 383, Kialegak; 581, —* 662, Boxer Bay; 805, Gambell. Several other reports. Range: arctic Siberia an aska-Yukon. Northern limit: zone 3. 72 STEVEN B. YOUNG 208. Pedicularis verticillata L. Common on backshores, often abundant on old village sites, near bird cliffs. SPECIMENS EXAMINED: Young 414, Kialegak; 1452, Gambell. Several other reports. Range: Eurasia and Alaska-Yukon; arctic-alpine. Northern limit: zone 3, reaching zone 2 at Wrangel Island. 209. Pedicularis parviflora J. E. Smith oi Pennellii ( Hult.) Hult. Fairly common on hummocks = wet SPECIMENS EXAMINED: Young 333, nioetiusnst Cape; 616, Boxer Bay; 755, Gambell. oe other reports. Range: amphi-Beringean. Northern limit: not clear, robe 210, Pedicularis Langsdorffii Fisch. (P. arctica R. Br.) a on moist eaicaage and alpine a EXAM +. Young 49, Tapphook 331, Northeast Cape; 364, ee 498, “Siknik: 631, ome Bay; 801, Gambell. Several beg reports. Range: America and Siberia; arctic- -alpine. ee dae limit: zone 211. Pedicularis sudetica Willd. mmo wet and mesic tundra. This is a complex circumpolar grow fone has iota been monographed by Hultén (1961). Two forms foun St are Diieabictilly found on the Alaskan main EC S EXAMINED: (ssp. albolabiata) ieee 433, Kialegak; (ssp. interiorioides) Young 95, 113, Tapphook; 196, 255, Reveonn* sn Northeast Cape; 411, Kialegak; 528, Siknik; 613, Boxer Bay; 758, Gambell. eral other pepartss Range: nearly circumpolar, absent in Greenland; arctic-alpine. bi eal limit: zone 2 212. Pedicularis capitata Adams Fairly common in moist alpine poe particularly near snow patches. SPECIMENS EXAMINED: Young 40. , Tapphook; 177, Savoonga; 269, ‘Northeast Cape; 355, Kialegak; 706, Boxer Bay; 775, ambell. Sev: , other reports. Range: North America and Siberia; arctic-alpine. deat limit: zon 213. Pedicularis Oederi M. Vahl Fairly common along grassy stream banks and in moist alpine situations. SPECIMENS EXAMINED: Young 44, Tapphook; 258, Savoonga; 696, Boxer Bay; 732 Gambell. Several other reports. Range: Eurasia and western North ropa arctic: alpine. Northern limit: not entirely clear; apparently reaches some zone 2 are 214. Pedicularis Kanei Durand (P. lanata Willd.) Common on drier alpine areas, occasional on backshor SPECIMENS EXAMINED: Young 28, Tapphook; 200, nea 285, Northeast — 437, Kialegak; 482, Siknik; -_ Boxer Bay. Several other reports. Range: circumpolar, i . North RUBIACEAE 215. Galium Brandegei Gray - os station found at the edge of a muddy, ephemeral pool near Gaedtuk. ; S EXAMINED: Young 1385, Gaedtuk. No —— reports, Range: alpine ead te ‘soak North America. Northern limit: zone 4, with zone 3 stations on St. Lawrence and west Greenland. VASCULAR FLORA OF ST, LAWRENCE ISLAND 73 CAPRIFOLIACEAE 216. Linnaea borealis L. Two sterile specimens found on moist alpine tundra. Both Kjellman (1882) and Muir (1918) note that this species was common on the northwest portion of the island when they visited there about 1880. It is now rare on all parts of the island. SPECIMENS EXAMINED: Young 356, Kialegak; 553, Gaedtuk. Also ences by Kjellman. Range: circumpolar, arctic and boreal regions. Northern limit: zone 4 VALERIANACEAE 217. Valeriana capitata Pall. Scattered on backshores and mesic tundra Seagate EXAMINED: Young 61, Ta pphoo ok; 219, perm oi Kialegak; 510, i Boxer Bay; 744, Gambell. Several other r reports. Range: Siberia and edeoyass Northern limit zone 3, with some zone 2 stations CAMPANULACEAE 218. Campanula lasiocarpa Cham Common in a few areas of mesic tundra and along river banks on the south side of the island. SPECIMENS EXA : Young 1332, Boxer Bay. No aoe reports. Range: amphi- Beringean. Northern 74 eae: zone 4 except for St. Lawren 219. Campanula uniflora L. A single station found in bas Db ocky tundra. SPECIMENS EXAMINED: Young 586, Gaedtuk. No previous reports. Range: frag- mented, peo circumpolar, but absent rt arnt of Siberia; arctic-alpine. Northern limit: zone 2 COMPOSITAE barat Mh Solidago multiradiata Ait Occasional, wa found in dry rocky stream beds in the southern and central rtions of the is a a EXA esa: oung 387, Kialegak; 561, Gaedtuk. Geist, 1933, Poovookpuk. Two other collections ey Geist listed by Hultén uae: Range: arctic and boreal regions of North America. Northern limit: southern zo e 3. a ae sibiricus L. single small station found on a Ogi river bar. The specimens are exceptionally be d bear onl Je hi one gras fens 1359, "Gaedtuk. No previous reports. cag ie inna European USSR, Siberia, and western North America. Northern limit: zon 222. Antennaria monocephala DC. Occasional, usually found on gravel bars along small streams. SPECIMENS Cte pe 183, Savoonga; aedtuk. Also reportedly collected by Anderson tiene 1950). Range: several closely — forms occur in arctic North America and Greenland. Northern limit: southern zo SPECIMENS EXAMINED: Youn Kialegak; 469, Siknik; 645, Boxer Bay; 732, Gam bell. Several other reports. Range: several disjunct areas in oo and boreal (ager ae seta aN ited: ) 74 STEVEN B. YOUNG Hultén (1950) gives a single report of this species from St. Lawrence, but thinks that the location is incorrect. I have never seen this species on the island. 224, Artemisia globularia Cham. ex Besser Rare, found only in alpine areas near Boxer Bay. This characteristic species does ~_ seem a ot oe with any others of the A. arctica group ED: Young 685, Boxer Bay. Also soacbedlly collected by Esch- me (Hulten 1950). Range: Beringean endemic. Northern limit: not clear because of limited range, but reaches zone 2 at Wrangel Island. 225. Artemisia glomerata Ledeb. Rather common in d alpine areas in the Poovoot Range and near Ataakas Camp sessile heads, and with light colored margins of the involucral bracts. These specimens resemble A. senjavinensis, but they have a few hairs on the corolla, and therefore zone 2 at Wrangel Islan 226. Artemisia Tilesii Ledeb. mmon to abundant on backshores, lower alpine areas. Especially abundant on old village sites, where it is usually the dominant species. All specimens appear to belong to the typical arctic form, = Tiles ii. SPECIMENS EXAMINED: Young 80, Tapphook; 250, Savoonga; 318, Northeast Cape; 542, Siknik; 791, ie Several other reports. Range: nearly circu wages eae: in Greenland, eastern Canda and western Europe. Northern limit: lower z 227. Artemisia arctica Less. Common ee abundant on backshores, hummocks of wet tundra, and lower oe a populations of this species on St. Law Specimens with rust-red pubescence on the spike [ss (Hult.) Hult.] appear to be randomly distributed with populations of the more common form with yellow pubescence (ssp. arctica). Inter- mediates are sr = age SPECIM p: Young 68, 81, Tapphook; 241, Savoonga; 322, Northeast Cape; 37 Kialegak, "343, Siknik; 641, Bice: Bay; 797, G decbell Several ae reports. Range: eastern Siberia and western North America. Northern limit: zone 228, Artemisia borealis Pall. A single station found in an alpine “op near Boxer Ba SPECIMENS EXAMINED: Young 725, oO previons Aad but Hultén (1968a) indicates a station on St. eget Range: nearly circumpolar, absent in East Greenland and western Europe. Northern limit; southern zon °3. 229. Artemisia furcata Bieb. (A. trifurcata Steph. ) ly common on rocky alpine areas in the southwestern portion of the island. This species sae to differ from A. glomerata mainly in its elongated, spike-like in- florescences. Some specimens crete to be intermediates. SPECIMENS EXAMINED: Young 557, Kongee; 643, Boxer Bay. Also i ne collected by Geist (Hultén 1950). ea eastern Asia and western North America; very fragmented. Northern limit: not clear 230. Petasites frigidus (L.) Franch. to abundant on backshores, moist tundra, and lower alpine regions. While VASCULAR FLORA OF ST. LAWRENCE ISLAND 75 the genus Petasites is notoriously difficult, all St. Lawrence specimens seem to fit well within P. frigidus, sensu stricto. SPECIMENS EXAMINED: Young 1, 721, 793, Gambell; 21, Tapphook; 162, 163, western half.” Several other reports. Ran ifficulties. Nearly circumpolar, absent from Greenland, may occur in eastern Canada (Cronquist 1946). Northern limit: northern zone 2. 231. Arnica Lessingii Greene Fairly common on mesic tundra and lower alpine regions, rare elsewhere. SPECIMENS EXAMINED: Young 286, Northeast Cape; 377, Kialegak; 714, Boxer Bay. Several other reports. Range: amphi-Beringean. Northern limit: not clear. 232. Senecio congestus (R. Br.) DC. Occasional, usually found at the edges of brackish pools and lagoons, particularly on the south side of the island. SPECIMENS EXAMINED: Young 310, Northeast Cape; 468, Siknik. Geist, 1933, Boxer Bay. No other reports. Range: nearly circumpolar, absent in Greenland; arctic-alpine. Northern limit: zone 2. 233. Senecio atropurpureus (Ledeb.) Fedtsch. Common on hummocks of wet tundra and in lower alpine areas; rare elsewhere. This taxon is extremely variable on St. Lawrence, but two rather distinct populations can be separated. One population has involucral bracts which are broad, rather short, and have no thick rootstock; the petals are usually long, broad, and clear yellow. The second population usually has longer, narrower involucral bracts; the stiff purple shade to somewhat shorter, thicker, pale brown hairs near the margin of the bracts. Specimens of this type commonly have several stems rising from a single rather thick rootstock. The petals are often, but not always, rather short and narrow; in the ried condition they are usually yellow-brown. The first population is apparently that which Hultén (1950, 1968a) treats as ssp. atropurpureus, while the second corresponds to ssp. frigidus (Richards. ) Hult. If central Alaska and the Arctic Slope, intermediate specimens do occur. I believe at an intensive biosystematic study of this complex would indicate that at least two distinct species are involved. Possibly polyploidy or some similar phenomenon is responsible for some of the anomalous material from other parts of Alaska. Within ssp. atropurpureus are two rather well-marked varieties. One, var. tomento- sus (Kjell.) Cuf. (ssp. tomentosus ( Kjell.) Hult., according to Hultén (1968a ), is characterized by somewhat dentate leaves and a dense tomentum of brown hairs on i rm was 234. Senecio resedifolius Less. : Occasional on fell-fields and dry alpine areas. The corolla of the ray flowers varies considerably in length. 76 STEVEN B. YOUNG SPECIMENS EXAMINED: Young 274, Fossil River; 585, Gaedtuk; 686, Boxer Bay. Geist, 1933, Boxer Bay. Also reportedly collected by Chamisso (Hultén 1950). Range: Siberia and western North America, with a disjunct population in eastern Canada; arctic-alpine. Northern limit: northern zone 3, with some zone 2 stations. 235. Senecio pseudo-arnica Less. Common to abundant on foreshores, less common on backshores. Most specimens are of short stature and bear a single head. SPECIMENS EXAMINED: Young 83, Tapphook; 346, Northeast Cape; 460, Kialegak; 484, Siknik; 650, Boxer Bay; 731, Gambell. Several other reports. Range: coastal areas of the Bering Sea and North Pacific. Disjunct populations in eastern Canada. Northern limit: not clear. 236. Saussurea viscida Hult. Occasional on moist and dry tundra. Saint Lawrence Island is the type location for this species, which is characterized by viscid, not arachnoid, pubescence on the leaves (Hultén 1950). Most of the St. Lawrence specimens have this character, but it is not uncommon to find some arachnoid pubescence, particularly on the upper leaves of young shoots. SPECIMENS EXAMINED: Young 111, Tapphook; 264, Fossil River; 565, Gaedtuk; 1305, Gambell. Several other reports. Range: Beringean region to western Mackenzie dist. Northern limit: not clear. 237. Taraxacum ceratophorum (Led. ) DC. The problems in the genus Taraxacum are so well known that they need not be commented on here. Haglund (in Hultén 1950) attributes 54 species of the genus to laska. More recently Hultén (1968a) claims that 11 major groups, most of which correspond to species, occur in Alaska. Five of these, T. ceratophorum, T. lateritium, T. hyparcticum, T. alaskanum and T. kamtschaticum are said to occur on St. Lawrence. I have seen none of the specimens on which these reports are based, but most of them are listed by Hultén (1950). . the specimens I have examined, there appear to be two reasonably con- EXAM 9 A ec: the genus Taraxacum is nearly ubiquitous. According to Hultén (1968a), T. cerato- p i = 238. Taraxacum alaskanum Rydb. (T. lyratum (Led.) DC.) Occasional on dry tundra and on the broader barrier beaches. None of the pecim i have mature achenes, and the identification is based on the broad involucral bracts which have a much reduced appendage. SPECIMENS EXAMINED: Young 98, Tapphook; 256, Savoonga. Range: probably eastern Asia and western North America. Northern limit: not clear. VASCULAR FLORA OF ST, LAWRENCE ISLAND Tt SECTION II. FLORISTIC ZONATION IN THE ARCTIC REGIONS INTRODUCTION The most salient feature of the St. Lawrence Island flora is the com- parative paucity of species included in it. The island's flora is now well-known, and the few species yet to be discovered must either be rare or of limited range. Most of them will probably be found on the south slopes of the mountains on the eastern end of the island. It seems reason- able to estimate that the total vascular flora of the island is in the neighbor- hood of 250 species. Many of these species are of rare or local occurrence on St. Lawrence. Hence, it is often possible to make an intensive collection over an area of several square miles and find no more than 125 to 150 species of plants. This is particularly true in the northwestern and north- eastern portion of the island. The flora of many mainland areas in Arctic Alaska and Siberia is much richer than that of St. Lawrence Island. At least 500 species of vascular plants are known to occur on the southwestern Seward Peninsula in an area comparable in size to St. Lawrence (Hultén 1968a), and about 75 species unknown on St. Lawrence occur in the vicinity of Cape Chaplino, Siberia, only about 40 sea miles away ( Hultén, loc. cit.). Even in the few square miles of the Ogootoruk Creek drainage, which is 300 miles farther north than St. Lawrence, Johnson et al. (1966) collected over 300 species of vascular plants. The point has been made elsewhere, but should be emphasized, that many of the species not known to occur on St. Lawrence are common and of considerable ecological importance on the nearby Alaskan mainland. Among the more notable examples are Salix glauca, S. alaxensis, Spiraea Beauverdiana and Rhododendron camtschaticum. The first three are abun- dant in mesic tundra and along watercourses throughout most of western Alaska. Rhododendron camtschaticum often forms nearly pure stands, sometimes several acres in extent, on the drier uplands of the Seward Peninsula. Many of the species not known to occur on the island produce copious amounts of wind dispersed propagules (e.g., Salix), and there can be little doubt that they are regularly transported to St. Lawrence from the Siberian or Alaskan mainland. The absence of these species on the island must be attributed to currently acting ecological factors which inhibit their establishment. Support for this view is provided by the numerous species which are of rare and/or local occurrence on St. Lawrence, but which are important constituents of the vegetation of nearby mainland areas, This is particularly evident in the cases of such species as Erio- phorum vaginatum, Betula nana, Empetrum nigrum, Epilobium angusti- folium, Ledum decumbens, Vaccinium uliginosum and many others. Since these species actually occur on St. Lawrence, but do not become 78 STEVEN B. YOUNG a significant part of the vegetation, there can be little doubt that the difference in their status on St. Lawrence, as compared to the adjacent mainland areas, is the result of differences in the environment of the areas involved. The large size and physiographic complexity of St. Lawrence Island indicates that a lack of suitable physical habitat is of little importance in limiting the ranges of the species mentioned above. It is interesting to compare the flora of St. Lawrence Island with that of some other arctic areas. For example, there are over 200 species of vascular plants on the Pribilov Islands (Hultén 1968a), roughly the same number as on St. Lawrence, although the area involved is much smaller. The Pribilovs are situated in the Bering Sea, 300 miles south of St. Lawrence. Both areas have had a similar Pleistocene history in that both were included in the Bering Land Bridge, although the land connection to the Pribilovs may have been severed at a somewhat earlier date than that of St. Lawrence (Hopkins 1967). Many of the Beringean endemic species are found in both locations and their vegetation is similar. It is surprising, therefore, that the Pribilov flora contains over 20 genera and 75 species of vascular plants which are unknown on St. Lawrence. This means that of the more than 300 species included in the combined floras of St. Lawrence Island and the Pribilovs, less than 150 (or less than 50 per cent) are common to both areas. If the flora of St. Lawrence is compared to that of the south island of Novaya Zemlya, which also has a flora of 208 species (Tolmatchey 1936), about the same degree of similarity is found to exist. However, Novaya Zemlya is on the opposite side of the Arctic Ocean, has a history of recent intensive glaciation (Flint 1957), is several hundred miles farther north than St. Lawrence, and has little or no access to the richly endemic flora of the Beringean region. There are also several cases in which a circumpolar complex is represented in each area, but by closely related vicarious species. If these were merged, the floristic similarity between the two areas would be increased. The similarity between the St. Lawrence Island flora and that of Wrangel Island is particularly striking. The flora of Wrangel Island, as presently known, includes 180 species (Hultén 1968a), of which the vast majority also occur on St. Lawrence. Many of the St. Lawrence species which are not known to occur on Wrangel Island are confined to a few isolated stations on the south side of St. Lawrence. Even if these rare or local species are considered, the St. Lawrence Island flora is much more similar to that of Wrangel Island than to that of the Pribilovs. Many more examples could be given to show that similarities and differ- ences between various arctic floras are not strongly dependent on geographical proximity or the Pleistocene history of the areas under con- sideration. I interpret this to mean that the similarities and differences between the floras of these arctic areas are, to a considerable degree, the result of similarities and differences in the current environment of the areas, rather than historical and distributional factors. The evidence dis- cussed below indicates that this generalization may be applicable to the VASCULAR FLORA OF ST, LAWRENCE ISLAND 79 entire arctic flora. It then follows that at least a portion, perhaps the major part, of the arctic flora must be more or less at equilibrium with its en- vironment. The species involved must have essentially filled their potential range under present conditions in the arctic. The flora and vegetation of the arctic are relatively uniform and simple in comparison with other major geographical regions of the world. The tundra is the only vegetation formation and in the entire arctic there are hardly more than 1000 species of vascular plants known to occur (cf., Polunin 1959). A measure of the uniformity of the arctic flora is that over 600 of these species occur in arctic Alaska alone (Hultén 1968a). A considerable fraction of these species have a circumpolar range, and many species whose range is less than circumpolar are nevertheless widespread. It is important to note that practically no species are endemic to the higher arctic regions. Along a transect from the southern edge of the arctic to the shores of the polar sea, certain species drop out of the flora as one travels northward. However, species which drop out are seldom replaced by new ones, as would be expected in temperate or tropical regions. Instead, the more northerly part of the transect be- comes increasingly depauperate. On certain large islands in the Arctic Ocean there are less than 50 species, and there is little or no continuous vegetation. This suggests that competition may be a factor of little or no importance in the disappearance of certain species from the upper portions of the arctic. If the disappearance is ecologically induced, as seems to be the case, the limiting factors which operate must be non-biotic—for example, climate. It is suggested that the northward spread of species of arctic plants is controlled by the interaction of a very few environmental factors, perhaps even a single factor. An expected result is that groups of species, not necessarily of close taxonomic relationship but with similar northern limits of distribution, may be found. In this study, I have proceeded on the assumption that if a reasonable proportion of arctic plant species, arctic flora. Once established, these zones would be predictive to the ex- tent that the presence or absence of a relatively few common species would designate to which zone an area belongs. It would also be possible to predict, with some degree of accuracy, what other species would be expected to be found in the area, and, more importantly, what species would not be expected to occur there. If it is correct to assume that the northern limits of species distributions are strongly influenced by a relatively simple set of limiting factors, it is to be expected that the patterns formed by groups of species with similar northern ranges are correlated with some ecological factor or group of factors, such as a climatic parameter. A great amount of distributional data for the arctic species of vascular plants have recently been summarized in the form of 80 STEVEN B. YOUNG dot maps by such workers as Hultén (1958, 1962), Tolmatchev (1960- 1966) and Porsild (1964). With these maps, it is possible to examine in detail, the ranges of a large number of species, and to see the similarities and differences. Ultimately, significant patterns of distribution are dis- cernible. In the following section, major patterns of distribution that occur in the arctic flora are discussed. It is evident that the arctic does, in fact, have distinct zones of increasing depauperateness of vascular plant species from south to north, Evidence is presented which indicates that the progressive loss of species from south to north is closely related to the amount of warmth available during the summer growing season. CONCENTRICITY OF NORTHERN Liwir oF DistRIBUTION OF MANY Arctic PLANT SPECIES An examination of the published distribution maps will show that few of the circumpolar or widespread species of arctic plants are uniformly distributed throughout the entire arctic. Instead, it is the rule, rather than the exception, that a species will have one or more gaps in its distribution in the more northern parts of the arctic, Also, it is evident that the loca- tions of these gaps are often nearly identical for a number of species which are taxonomically unrelated. For example, Equisetum variegatum, Erio- phorum angustifolium, Dryas integrifolia and Cassiope tetragona (Fig. 4, 5, 6, 7) are all of nearly universal distribution throughout the North American arctic. All are usually among the most common species at any given station. However, none of these species is known to occur in one small area in the northwestern corner of the Canadian Arctic Archipelago. This area includes Elif Ringnes and Amund Ringnes Islands and the smaller Brock, Borden, Mackenzie, King, Lougheed, and Meighen Islands, as well as parts of Prince Patrick, Melville, Bathurst, Devon, and Axel Heiburg Islands. There are a number of other species whose ranges in northern Canada are practically identical to those of the four examples given. A further examination of the distribution maps indicates that, among species which are widespread in arctic North America, there is an entire series of groups of plants whose northern range limits are similar. These groups are easily placed in a natural sequence where the gaps in their distribution increase in size until the last groups are made up of species which are not known to occur in the Canadian Arctic Archipelago. A general picture of this can be seen in Fig. 8, where the northern limits of distribution of a number of widely distributed North American arctic species are plotted. The evidence supports the conclusion that many species, which are common and widespread throughout much of the North American arctic, drop out of the flora of a north to south transect in a definite sequence. The sequence is approximately the same whether the transect is drawn in Alaska, the Canadian Arctic, or Greenland. However, the point at which a particular species drops out is not correlated with any particular latitude. VASCULAR FLORA OF ST. LAWRENCE ISLAND 81 The distance over which parts of the sequence are completed is also subject to much variation. For example, in Alaska, the northernmost station for Rhododendron lapponicum, is only 50 miles north of the northernmost station for Epilobium angustifolium, but in West Greenland the range of R. lapponicum extends about 500 miles north of that of E. angustifolium. In this study, the logical next step was to determine whether the same situation as that described above would hold true on a circumpolar basis. Comparing distributions over the entire arctic is difficult for several reasons. The number of species which can be compared is considerably reduced, as it is necessary to use only common circumpolar species to make a valid worldwide comparison. In addition, no detailed data have been published on the Asiatic distributions of a number of circumpolar species. For this reason, monocotyledons may seem to be over-represented in the following discussion, simply because there are more accurate distributional data available for them than for dicotyledons. Also, there may be a great deal of variation in a given species when it is treated over its entire circumpolar range. This presents taxonomic difficulties when discussing the range of a given species. Allied to this is the problem of regional differences in the taxonomic treatment of the species involved. Finally, geographical differences between the Eurasian and North American continents add a complicating factor. In North America, the arctic regions form a compact unit including Greenland and most of northern Canada, with extensions along the coast of Labrador and northern and western Alaska. On the Eurasian continent, however, the arctic region consists of a narrow and somewhat discontinuous strip along the arctic coast of the mainland, and then several more or less isolated islands and archipelagoes within the Arctic Ocean. The ranges of the tundra species are therefore often rather disrupted in Eurasia, particularly along the northern coast of Siberia. The sequential loss of a group of species may take place over a south to north distance of 1000 miles or more in Greenland or Canada, whereas the same species loss may take place over such a short distance (often less than 100 miles) in arctic Siberia that the sequence is either disrupted or not visible on a large scale map. Even with the handicaps noted above, when the total ranges of the common circumpolar species are plotted (see Fig. 9-16), it can be seen that the same general situation described for North America holds true throughout the entire arctic. As might be expected, because of the geographical differences indicated above, depauperization of the arctic flora from south to north is not particularly evident on the Eurasian mainland. It is usually not until the arctic islands are considered that a significant reduction in the number of plant species is evident. Thereafter, loss of species takes place rapidly. Some of the Soviet archipelagoes support the most depauperate flora in the entire arctic. Only 36 species of vascular plants have been reported from Franz Josef Land (Hannsen & Lid 1932), and apparently the Severnaya Zemlya archipelago, in spite of its comparatively large geo- §2 STEVEN B. YOUNG Equisetum variegatum oe 1 Greenland~ misandra Fies. 4 anp 5. Range of Equisetum variegatum and Carex misandra in arctic Canada and Greenland. VASCULAR FLORA OF ST, LAWRENCE ISLAND 83 Hudson —<__ — Bay \ Fics. 6 AND 7. Ranges of Dryas integrifolia and Cassiope tetragona in arctic Canada and Greenland 84 STEVEN B. YOUNG graphical area, supports even fewer species. This is not the result of geographical isolation, as is indicated by the fact that the much smaller and more isolated Svalbard archipelago, at about the same latitude, has a vascular flora of over 150 species (Rénning in Live & Live 1963). A final point on the progressive loss of species from south to north is that the phenomenon is not confined to the circumpolar species. Most arctic species of vascular plants whose ranges are less than circumpolar have northern range limits which essentially parallel those of the circum- polar species. Therefore, a group of several species of less than circumpolar range may have an aggregate range whose northern limit is comparable to that of a single circumpolar species. Wide ranging species whose ranges are less than circumpolar can usually be assigned to groups in essentially the same manner as can circumpolar species, with respect to the northern limit of their range. < * = K eS ‘ Fic. 8. Northern limits of distribution (reading from south to north) of: Eleocharis acicularis, Pedicularis lapponica, Tofieldia pusilla, Pyrola grandiflora, Melandrium affine, and Juncus biglumis fe, Ve DIvipING THE ARCTIC INTO FLORISTIC ZONES The concept of the division of the northern parts of the world into floristic zones is not new. Geographers define the arctic as being the treeless tundra areas in the far north. The timberline, or the poleward limit of arborescent conifers, forms a boundary between the arctic and subarctic zones. As the timberline is essentially the northern limit of range of the family Pinaceae, specifically the genera Picea and Larix, it constitutes a definite floristic boundary, although it is thought of as a vegetational undary. The boundaries proposed here are a continuation of the same line of reasoning that considers the timberline the arctic-subarctic bound- ary. The essential difference is that within the arctic region there is no vegetational boundary comparable to the timberline. Zone boundaries within the arctic must be drawn almost entirely on a floristic basis, and the choice of species used to define the boundaries is somewhat arbitrary. The positions of the zone boundaries could be moved north or south, VASCULAR FLORA OF ST. LAWRENCE ISLAND 85 depending on the species or groups of species used, and a number of zone boundaries could be drawn. No matter how many are used, or what species groups define them, the boundaries should theoretically retain the same relationship to each other because of the concentricity of the northern limits of the ranges of the species involved. The system of four zones proposed here (Fig. 17) seems to be a reasonable compromise in the light of the available evidence. If more zones are drawn, there is an implication that the zonation system is more accurate than the distributions of the plants, as they are presently known, would warrant. Also, a considerable number of species begin to show up whose northern range limits are anomalous because they cross zone boundaries. It is true that fairly large numbers of species have northern range limits which characteristically fall within a particular portion of one of the proposed zones, and one might be tempted to increase the number of zones or draw subzones because of this. However, it seems more reasonable to mention that the northern limit of range of some species is, for example, in southern zone 2, or northern zone 4, with no implication that a well-delineated subzone exists. If less than four zones are drawn, the differentiation between the lower and upper portions becomes too great, and the zones become too inclusive. There is some justification for treating the taiga region as a fifth zone. However, in the subarctic, the ranges of most species of plants are much more fragmented than in the higher latitudes. Only a small fraction of the species involved have ranges which form patterns comparable to those used to define the arctic floristic zones. The timberline would make a reasonable northern boundary for a fifth zone, but the southern boundary would be difficult to define on a worldwide basis. The proposed system of floristic zonation based on concentricity of the northern limits of distribu- tion can be effectively applied only in the polar regions. The explanation for this seems to be that the northern limit of distribution of most polar plants is largely dependent on a single limiting factor, the amount of available warmth during the growing season. This is discussed in detail later. In temperate regions, coastal and high altitude areas often support a flora which includes many boreal and even arctic elements. Similarly, boreal elements occur in the arctic, particularly in coastal regions. Small islands and sea coasts often support a flora characteristic of a zone farther to the north than adjacent mainland areas. Most of these areas are too small to be taken into account here, but it should be noted that the zone of an area should not be based only on collections from coastal areas. Description of the Zones. The boundaries of the four zones are given in Fig. 17. In terms of land area, zone | is the smallest of the four. It includes a few island groups and scattered islands in the Arctic Ocean; the most important areas are Franz Josef Land, Severnaya Zemlya and the northern edge of the Taimyr Peninsula near Cape Chelushkin, most of the New Siberian Islands and some of the islands in the northwest corner of 86 STEVEN B, YOUNG B de ‘ rh Juncus 3 —. en IS SVP bi . ? “ag Ve ¢ is er iglumis Woe ¢ Pes hae e \ c 8 Fic. 10, Circumpolar range of Oxyria digyna. VASCULAR FLORA OF. ST. LAWRENCE ISLAND \ WS mn . of ey a & ig be) O85: 65, e AN 2 i ‘ ee Sry fs + 2 “5° S , e —— 4 a i ae eR Ve es Equisetum \, 6, Seats ms Pa r : > : arvense (arctic range only) X E oN rt Loe 3 of Equisetum arvense. Note lack of stations of this species in . Circumpolar arctic range hehehe tae Canada, Franz Josef Land, Severnaya Zemlya and northern New Siberian Islands. Oat), Carex misandra ean ee of Carex misandra. The northern limit of this species is similar to Fie. 12. Cire that of Equisetum arve STEVEN B. YOUNG Carex Ni Lachenalii Fic. 13. Circumpolar range of Carex Lachenalii. Pyrola grandiflora Fic. 14. Circumpolar tange of Pyrola grandiflora. VASCULAR FLORA OF ST. LAWRENCE ISLAND RL ESS AON Vie ss § = Ad e e ‘ * A 4 3) e e a eh 's { Ws SHUR Eh ty op SEK Rath ES, 2 aA Pe PSG ; re e ge el ey - 4 eae. Sel re t os e g a . ; D © e e r) oft at Lycopodium ee eae AS, annotinum AS Fic. 15. Circumpolar range of Lycopodium alpinum. tt EY SN ONY ee x =e bd QUT, ey YEG ae, 4 J 2 = ire 8 F oy H J Calamagrostis ? ee < age : aN hay lapponica N C4 ° eens « Lox \ a Fic. 16, Circumpolar range of Calamagrostis lapponica. 90 STEVEN B. YOUNG the Canadian Arctic. Areas on the coastal fringe of northernmost Green- land and Ellesmere Island could be placed in zone 1, as well as some of the small islands in the northeastern part of the Spitzbergen Archipelago. The floras of all zone 1 areas are exceedingly impoverished, normally including no more than 50 species of vascular plants. About 50 species are known to occur on Elif Ringnes Island, while other nearby islands have fewer species (Saville 1961). Thirty-six species have been collected in the entire Franz Josef archipelago (Hannsen & Lid 1932), Although exact figures are not available, the flora of Severnaya Zemlya seems to be even more impoverished. No vascular cryptograms are known to occur in zone TABLE 1. COMMON CIRCUMPOLAR SPECIES WHOSE NORTHERN LIMIT Is USUALLY IN ZONE 1. Alopecurus alpinus Minuartia rubella Phippsia algida Ranunculus sulphure Deschampsia caespitosa sensu lato aver radicatum sensu lato Arctagrostis latifolia Cardamine bellidifolia Poa arctica sensu lato Draba alpi ) igena Draba macr a Dupontia Fischeri sensu lato Draba subcapitata arex ursin Saxifraga caespitosa cus biglumis Saxifraga hirculus Luzula arctica Saxifraga Luzula co Saxifraga flagellaris Salix arctica sensu lato Saxifraga nivalis ia digyna Saxifraga rivularis Stellaria Edwardsii Saxifraga oppositifolia Cerastium aff. arcticum Potentilla hyparctica sensu lato 1 areas, although several species reach the northern edge of zone 2, and the northern limits of the ranges of Equisetum arvense and E. variegatum coincide almost perfectly with the boundary between zone 1 and zone 2. Most of the species found in zone 1 have a circumpolar, or nearly circum- polar, range. They tend to be species of common occurrence in a wide variety of habitats throughout the arctic regions. Few of the species which occur in zone 1 form extensive colonies, and closed stands of any sort are rare or absent. A list of species commonly found in zone 1 is given in able 1 Zone 2 includes the northernmost land areas in the world, northern Greenland and Ellesmere Island. Nevertheless, most zone 2 areas support a much richer flora than does zone 1. The flora of a typical zone 2 area usually includes 75 to 125 species of vascular plants. The area also includes most of the northern part of the Canadian Arctic Archipelago, Greenland north of about 79° lat. on the west coast and 76° on the east, most of the Spitzbergen Archipelago, northern Novaya Zemlya, the northern portions of the Yamal and Taimayr Peninsulas, and the southern islands in the New Siberian Islands. A small area in the vicinity of Point Barrow, Alaska, supports typical zone 2 flora. Wrangel Island seems best placed in zone 2; its flora is much richer than that of other zone 2 areas, but this is mainly VASCULAR FLORA OF ST. LAWRENCE ISLAND 91 attributable to the great variety of habitats on the island and its close proximity to the floristically rich Beringean region. Most of the character- istic zone 3 species are not known to occur on Wrangel Island. TABLE 2. COMMON CIRCUMPOLAR SPECIES WHOSE NORTHERN LIMIT IS USUALLY IN ZONE 2 Cystopteris fragilis Melandrium affine is rvense Ranunculus hyperboreus Equisetum variegatum nunculus pedatifidus copodium selago Ranunculus ni Hierochloe alpina Ranunculus pygmaeus Hierochloe pauciflora Cochlearia officinalis Trisetum spicatum sensu lato Eutrema Edwardsii Puccinellia phryganodes Cardamine pratensis Eriophorum angustifolium sensu lato Braya purpurascens Eriophorum Scheuchzeri Draba lacte Kobresia myosuroides Saxifraga foliolos Carex rupestris hieracifolia Carex aquatilis Astragalus alpinus Carex misandra Epilobium latifolium Carex saxatilis Cassiope tetragona olygonum viviparum Pedicularis capitata Sagina intermedia Armeria maritima Stellaria humifusa Senecio congestis Melandrium apetalum Taraxacum ssp. Zone 2 includes most of the area traditionally called the high arctic. The flora here consists mainly of circumpolar or wide-ranging species, so that there is a strong similarity between the floras of various zone 2 areas. In contrast to zone 1, at least seven species of vascular cryptograms are known to occur in zone 2. A list of species characteristically found in zone 2 but whose ranges do not reach zone 1 is given in Table 2. 7 Zone 3 includes an area which is transitional between the floristically depauperate high arctic regions of zones 1 and 2 and the rich low arctic zone 4, Zone 3 floras, from all but the most remote areas, include well over 100 species. Even the isolated floras from the Inner Fjord District of Spitzbergen and the Eureka area of Ellesmere Island, both at nearly 80 north, each include approximately 150 species. Less isolated zone 3 areas may support a flora of 250 or more species. Included in zone 3 are most of the southem and eastern portions of the Canadian Arctic Archipelago, as well as some mainland areas such as Melville and Boothia Peninsulas. included is West Greenland north of Disco Bay, East Greenland north of Scoresby Sound, the southwestern portion of Spitzbergen, Bear Island, Jan Mayan Land, southern Novaya Zemlya and Vaigatch Island, and a narrow, and somewhat discontinuous strip stretching from the Yamal Peninusla across arctic Siberia to the Bering Strait and along the north coast of Alaska. This coastal strip is usually less than 50 miles wide, and it is interrupted by zone 4 areas at the mouths of the larger rivers, such as the Lena, Olenek and Colville. 92, STEVEN B. YOUNG TABLE 3. COMMON CIRCUMPOLAR SPECIES WHOSE NORTHERN LIMIT IS USUALLY IN ZONE 3. Woodsia alpina Tofieldia pusilla Woodsia glabella Tofieldia coccinea ryopteris fragrans Salix reticulata Equisetum scirpoides Salix glauca Calamagrostis neglec Salix lan Calamagrostis purpurascens Betula nana sensu lato Poa alpina Koenigia islandica Poa glauca Montia fontana Festuca rubra Honckenya peploides Elymus arenarius sensu lato Draba hirta Eriophorum callitrix Ranunculus aquatilis sensu lato Eriophorum brachyantherum Ranunculus lapponicus Eriophorum russeolum Draba cinerea Eriophorum vaginatum Epilobium davuricum Kobresia simpliciuscula Hippurus vulgaris Carex scirpoidea Empetrum nigrum Carex Lachenalii Pyrola grandiflora Carex glareosa Ledum decumbens Carex subspathacea Loisleuria procumbens Carex rariflora Arctostaphylos alpina Carex capillaris Vaccinium vitis-idaea Carex Bigelowii Diapensia lapponic Juncus triglumis Pedicularis lapponica Juncus castaneus Artemisia borealis Luzula Wahlenbergii Arnica alpina In zone 3, differentiation between the floras of the various sectors of the arctic is much more marked than in zones 1 and 2. This is partially ac- counted for by the fact that there are no zone 1 and only small zone 2 areas between the western Canadian Arctic and the New Siberian Islands. Thus, with the exception of Wrangel Island, the highest zone reached by the richly endemic Beringean flora is zone 3. The presence of Beringean endemics on Wrangel indicates that many of these species have become adapted to live in the conditions of zone 2 areas. A list of species charac- teristically found in zone 3 but which do not normally reach zone 2 is given in Table 3. Zone 4 includes most of the area traditionally considered to be the low arctic. In contrast to the other zones, it is primarily restricted to mainland areas. Its land area is much larger than any of the others, being approxi- mately equal to their total. The composition of zone 4 floras varies greatly from one sector to another, tending to obscure the concentricity of the northern limits of the ranges of zone 4 species. The problems which make the theory of zonation inapplicable to the temperate regions becomes evident in zone 4. Although its flora contains several times as many species as zones 1 and 2, the percentage of circumpolar species drops off sharply and the number of characteristic species is hardly greater than for the other zones. Otherwise, it might be possible to separate it into two zones, since the difference in flora and vegetation between the upper and lower VASCULAR FLORA OF ST, LAWRENCE ISLAND 93 edges is often quite striking. There is also a noticeable difference between the floras of zone 4 areas in continental climatic conditions and floras TABLE 4. COMMON CIRCUMPOLAR SPECIES WHOSE NORTHERN LIMIT IS ONE 4 Gymnocarpium dryopteris Botrychium lunaria Carex atrata Juncus alpinus Luzula parviflora Alnus ssp. Betula glandulosa sensu lato Stellaria calycantha sensu lato Sagina nodosa Coptis trifolia Ranunculus reptans sensu lato Rorripa islandica u ctic Potamogeton gramineus bus ar: Potamogeton perfoliatus Potentilla Egedii Hierochloe odorata Sibbaldia procumbens Agrostis borealis Viola epipsila sensu lato Calamagrostis canadensis Epilobium angustifolium Calamagrostis lapponica Epilobium palustre Eleocharis aci i Myriophyllum exalbescens Scirpus cespitosus Pyrola secunda Carex bicolor Pyrola minor Carex brunnescens Andromeda polifolia Carex ca Menyanthes trifoliata Carex dioica Veronica alpin Carex chordorrhiza Pedicularis labradorica Carex rotundata Linnaea borealis from maritime situations. However, the circumpolar element is essentially similar. Zone 4 floras typically include over 200 species of vascular plants. Some of the richer floras, such as those of the southern Seward Peninsula, may contain over 500 species, about twice as many as are found in the richest zone 3 floras. Zone 4 includes nearly all of the mainland of arctic Canada, but only a few small areas in the southernmost part of the Canadian Arctic Archipelago. Also included are Greenland south of about 70° north, most of Iceland, the coast of northernmost Scandanavia and the Murman Coast, and a narrow strip along the northern edge of the Eurasian con- tinent from the Kanin Peninsula to the Chukchi Peninsula, then south along the Bering Sea coast of eastern Siberia. In addition, the Bering and Chukchi seacoast of Alaska and central Alaska from the Brooks Range northward are included. The Aleutian Islands, Komandorsky Islands, part of coastal Kamtchatka, and some areas along the coast of the Sea of Okhotsk are also included in zone 4. A list of some of the more charac- teristic circumpolar or widespread zone 4 species is given in Table 4. Because species can be placed accurately in appropriate zone categories on the basis of their northern limits of distribution, only a fraction of the 94 STEVEN B, YOUNG Shi oe % America. If the flora of Herschel Island is compared with that of Barter Island, which lies about 100 miles westward along the coast of Alaska, it will be found (Wiggins & Thomas 1962) that none of the species men- tioned above is known to occur on Barter Island, or are any other zone 4 species found there. One can therefore conclude that Barter Island is in zone 3 (or possibly a higher zone ) and that the boundary between zone 4 and zone 3 intersects the arctic coast somewhere between the two islands. VASCULAR FLORA OF ST. LAWRENCE ISLAND 95 CorRRELATION OF FLORIsTIC ZONES WITH ECOLOGICAL FACTORS The lack of correlation of the floristic zones with strictly historical or geographical factors has already been mentioned. There can be no doubt that ecological factors are of major importance in controlling the north- ward expansion of the ranges of arctic plants. However, the factors which have determined the present range of non-circumpolar species obviously must contain historical components as well. It has been noted that the arctic timberline forms the southern boundary of zone 4 and it is essentially a floristic boundary in that it is the northern limit of the genera Picea and Larix. One might expect that other floristic boundaries in the arctic would be correlated with ecological factors in much the same way. But research (cf., Kimball & Good 1955; Hustich 1953; Hopkins 1959b) indicates that the major ecological factor involved is the amount of available summer warmth. This was first proposed by Koeppen (1936, the latest statement of a much older theory) and Merriam (1894). Koeppen noted that there is a strong correlation between the location of the arctic timberline and the 10° C isotherm for the warmest month of the year. How exact this correlation is can be judged from the map (Fig. 18). The location of the timberline is shown quite accurately but that of the 10° C July isotherm is much more difficult to plot and over fairly long distances it is drawn between stations by inference. Local microclimatic or special conditions caused by altitude cannot be taken into account but it can be assumed that, within these limitations, the location of the 10° C July isotherm is reasonably accurate, perhaps to within two degrees C. In the far north the timberline lies south of the 10° C July isotherm. The greatest distance occurs in areas near large bodies of water and is apparently an effect of maritime climatic conditions. Various systems have been proposed to describe a climatic boundary which approximates the timberline more closely than does the 10° C July isotherm. The best known of these is the Nordenskjold line (Nordenskjold & Meckling 1928), which takes winter as well as summer temperatures into account. Merriam (1894) proposed that the northern limits of the ranges of many species are more dependent on the total amount of warmth available during the growing season than on any temperature level at a specific time. Hopkins (1959a) used a similar approach by showing that the timberline in western Alaska can be closely correlated with the number of degree days above 10° C during the summer. The July isotherm for a given tempera- ture does not adequately express the amount of available warmth. In some maritime areas, August is the warmest month of the year, and there is a good deal of variation in temperatures for other months of the growing season between areas whose July mean temperature is comparable. A better means of expressing the amount of warmth must be developed to correlate the northern limit of the ranges of plants and the amount of available warmth during the growing season. 96 STEVEN B. YOUNG oa fae, yy sete ech G. 18. Approximate location of the 10° C isotherm for the month of July (black line) and arctic tundra areas (shaded). Data from several sources, It also must be recognized that standard data from weather stations are not an entirely adequate index of the temperature regime of a given area. Temperature data at weather stations are normally gathered at a height above the ground of several feet, while the effective temperature for tundra plants is the temperature near the soil surface. Standard weather station data must be used because nothing else is available, although they are not particularly accurate for the purpose. "One method of determining warmth during the growing season is to sum the mean temperatures of all the months having a mean temperature above 0° C, This gives a more accurate figure than that of the isotherm, it can be computed rapidly from published data, and does not imply an unjustified degree of accuracy. For convenience, the aggregate of mean temperatures above 0° C (in degrees C) will be referred to as a. The use 0° C for a base point from which to compute a is arbitrary. Since permanent ice and snow normally cover areas in which the mean temperature does not rise above 0° C for any month of the year, a value of VASCULAR FLORA OF ST. LAWRENCE ISLAND 97 a=0 corresponds closely with the absolute limit of vegetation. However, there is no implication that 0° C is a critical limit for plant growth. In any case, the summer temperature curves of arctic stations are regular enough so that a computed from a base point of 0° C is well-correlated with a similar figure computed from a base point within a few degrees of 0° C (see Fig. 19-23). ese figures show climatographs from a series of arctic stations at about timberline and in each of the four floristic zones. The location of each station is given in Fig. 24. Several conclusions can be drawn from the data presented. First, there is no significant correlation between annual mean temperature and the floristic zones. Mean annual tempera- tures in some zone 1 areas are actually higher than in some timbered and timberline areas (see Table 5). This suggests that winter temperatures are not a significant factor related to floristic zonation. Second, mean annual precipitation shows no significant correlation with the floristic zones, although there is some tendency for precipitation to be less in the higher arctic regions. Third, summer temperatures are strongly correlated with the zones. It is not possible to assign given values for the mean temperature for any month of the year to given zones, but it is strongly suggested that the summer temperature regime of each of the zones falls within rather exact limits of a. Zone 1 stations characteristically have an a between 0 and 6, zone 2 between 6 and 12, zone 3 between 12 and 20, zone 4 between 20 and 35, and stations in timbered country usually have an a of over 35. Values of a for some additional stations are given in Table 5. Unexpectedly low a values occasionally occur, as in the case of Resolu- tion Island, with an a of 11, although adjacent parts of Baffin Island are in zone 4 and the lower part of zone 3. Cases of this sort are almost always related to an extremely maritime climate. As noted, the floras of these areas are impoverished, and the areas can be thought of as “islands” of a higher zone. The situation is reversed in a few areas with a highly continental climate. This explains why parts of Ellesmere Island, at about 80° north, are in zone 3. Peary Land, Greenland, the northernmost land in the world, has a highly continental climate. Although it lies at about 83° north, both the flora and a value have some characteristics of a zone 3 area. There is no significant correlation between the floristic zones and day length. If day length were an important factor in controlling the distribution of arctic plants, it would tend to even out some of the major northward and southward extensions of the various zones, since it is entirely dependent on latitude. In any case, during much of the summer, day length is essentially the same throughout the entire arctic. Even at latitude 60° north, there are several weeks during which night never falls, although the sun is slightly below the horizon for a few hours out of each twenty-four. It has been shown that most plant species that are sensitive to day length are also sensitive to light intensities of only a fraction of 98 STEVEN B. YOUNG TABLE 5, FLORISTIC ZONE, @ VALUE, MEAN ANNUAL TEMPERATURE OF SELECTED ARCTIC AND SUBARCTIC STATION: e numbers in parentheses indicate that the station is near the boundary of that zone (data from Walter, 1960). Mean ann. Station Zone a®™ temp. (°C) Alaska Barter Island 213) ll -11.9 Shishmaref 4 24 -6.6 Wales 4 28 Says Saint Michael 4 (subare.) 33 -3.4 Canada Mould Bay 1 (2) 6 -17.8 e 3 (2) 12 12.0 Pond Inlet 3 (2) 14 14.1 Arctic Bay 2 (3) 15 —13.5 Padloping Island 3 16 -10.3 an Isla 3 155 me lag Coral Harbor 3 (4) 19 -11.8 Frobisher 4 (3) 22, —-9.0 Chesterfield Inlet 4 24 HES ort Harrison 4 25 2715 Port Radium subare. (4) 37 -6.8 Fort Mackenzie subare. (4) 36 5.1 Greenland Danmarkshavn yA 9 -114 Inglefield Bay 2 10 -12.5 Thule 3 (2) 12 hid Peary Land 2 14 -15.0 Scoresbysund 3 16 -6.3 Umanak 3 (4) s§ —2..8 Godhavyn 4. 24 —0.9 Angmagssalik 4 28 0.9 Godthaab 4 31 0.8 Kornok 4 (subare.) 39 0.6 Sletten 4(subare.) 41 1.6 Jan Mayen Island 3 (4) 19.5 0.0 Bear Island 17.5 -5.0 Spitzbergen : —_ Hook 2 10.5 -6.7 Green Harbor (2) 14 -8.0 Iceland Grimsey 4 32 1.6 Akureyri 4 (subare.) 41 2.3 Reykyavik subare. (4) 54 3.9 Norway Troms¢ subare. (4) 42 2.3 Varde 4 (subare.) 35 1.1 Rést ( Lofoten Is. ) subare. (4) 58 AT Franz Josef Land Rudolph 1 1.0 Lie European Russia Aleksandroysk 4 (subare.) 36 0.3 Kola 4(subare.) 41 -0.7 Kanin Nos 4 3 ii Kolgujev I. 4 25 3.0 VASCULAR FLORA OF ST, LAWRENCE ISLAND 99 TaBLE 5 (continued ) Mean ann. Station Zone a® temp. (°C) Novaya Zemlya Cape Shelanija 2 (1) 6 -9.2 skaya Gavanj 2 8 2 Matotchkin Shar 2°(3) 12:5 -8.5 Malyje Karamenkaly 3 17 —6.0 Varneka Bay (Vaigatch) 3 19 7 Western Siberia Bely I. vA 12, —9.7 Cape Drovjanov 2, 13 -9.9 Dixon 2 8 —12.7 Dudinka 4 (subare.) 31 -10.7 Igarka subare. (4) 41 -8.6 Eastern Siberia Cape Shelagshi 2 12 -12.2 Uelen 3 14.5 8.6 Chatanga 4 26 -13.5 lun 4 pag —14.4 Anadyr 4 30 -7.9 Abyj subare. (4) 38 -14.4 Verkoyansk subare. 45 -16.1 New Siberian Is. Kotelny I. 1 5 -144 Cape Kigiljaka 241) 6 -14.2 Liakovsky I. 2 (1) 6.5 —14.7 Okhotsk Region Okhotsk 4 (subare.) 36 —5.7 Kamtchatka Ust Kamtschatsk subarctic 45 £2 Commander Islands Bering I. 4 (subare.) 42 —1.5 * Ageregate of mean temperatures above O° C. those of broad daylight (Meyer, Anderson & Bohning 1960). Day length is therefore excluded as a major factor in affecting the distribution of arctic plants. All zonal soils in arctic regions are generally considered to fall into a single category, arctic brown soils (Tedrow & Cantlon 1958). They are rather uncommon, particularly in the higher arctic regions. Most arctic “soils” are azonal bog soils and lithosols which are so universally dis- tributed throughout the arctic that there is little chance of their affecting plant distribution on a broad scale. None of the floristic zones can be characterized as to soil type or other edaphic features. Although the floristic zones are correlated with the amount of summer warmth to the point that other ecological factors are insignificant by com- parison, not all arctic plants conform to the zones in terms of their northern limit of distribution. In some cases, this can be explained on the basis of ecological factors, other than summer warmth, affecting the northern limit of distribution of certain species and plant groups. This is discussed in the following section. STEVEN B. YOUNG me a=36 oO o 6 OSEM IAS NN . OP ++ A+++ a e . eee he mean 2 20 o-8 ; a g ~30 — ISO ao 654 = a sre ey eee Pn st Oy er 1. Port Radium, 2.Great Whale River, Northwest Terr. Quebec 3. Hopedale, 4. King Salmon, Labrador Alaska a=37 a=42 5 Sredni Kolymsk, 6. Tromso, Siberia Norway ore eae dey . Climatographs from several stations near arctic bar ijn a is the aggregate of t Pu aeomnne of the months hi with a n temperature above area se the curve. Data mainly from Walter (1960) PC. Phe h is equal to the cided VASCULAR FLORA OF ST. LAWRENCE ISLAND 101 mean temp. (°C) ~ O — 7. Holsteinburg, Greenland ~~ 7 fee ° + + f, . ' ‘ ns e SESAME EY aEeh do oe per ca ee e, ro-e-@ aietais 9. Tiksi, Siberia 11. Churchill, Manitoba 146 a=33 a8, 10. Anadyr, Siberia Bie ic hag ie Mics = en ta p< cal a Fae 4 a=25 12. Port Harrison, Quebec 169 Frc. 20. Climatographs for several stations located in zone 4. Data as for Fig. 19, 102 STEVEN B. YOUNG mean temp. (°C) 13. Savoonga, Alaska F mat 15. Upernavik, Greenland eave one eee S Aka a A 3 jaz=1Z5 Po Z OSEMAMS oT 1 ee bd ain Beer na iy GS gee ae ean 2OLS4 ++ annual pt. ere . 256mm 230 P|=- ee ewe ewe ew ewe ew we ec ew 4 MRS s a aes. =i gies ‘e 14. Eureka, Northwest Terr. 16. Barentsburg , Svalbard 398 18.Cape Medveshi, Siberia Fic. 21. Climatographs for several stations located in zone 3. Data as for Fig. 19. VASCULAR FLORA OF ST, LAWRENCE ISLAND 103 20 ee — ie a ee we re rt . sn 4. 1O P eats 6 bh eee S “JFMAMJJASOND ca 1 — — an a 1U a e ee ee s ; Bigs = MS RIBS Sone © 5 30k ane bert saree Se © ed a 19, Resolute, Northwest Terr. eaten mien cus NEO | Rn Sie Be, RR 23. Wrangel Island, Chukchi Sea ate A +4 annua e | ppt. 130mm 198 lis Saat a T iit pt Fee ea armen at SE 4. en Gee tee ee ete on dl +—+—+ + + Be | pees ean ea Cacia ete \caake ae) llam, ee, ad @ ae 9 \ ‘e. ee ~ ee ee Sas + 4 —— —- ae n Fane) cade! et Seon nee 20. Quade Hook, Svalbard , 9 4 4 T a ‘ 22.Bolshoi Island, New Siberian Is. eee er eee era Bi ae a as i th ae Ree TY : na - 2 ae bs ite On ae a ee» 104 ‘ re 27.Cape Chelushkin, 28.Kotelny Island, Siberia New Siberian Is. sah ae aeseana ~ ec a seat ig, aD eee aes Se. Fy. 0 SOE REN, Ne d ¥Y 100 }e-e-@ 29. |Isachsen, 30. Alert, Northwest Terr. Northwest Terr. Fic. 23. Climatographs for several stations located in zone 1. Data as in Fig. 19. VASCULAR FLORA OF ST, LAWRENCE ISLAND 105 ed gle Nt Fic, 24. Map showing locations of the 30 stations treated in Figs. 19-23. Plants Which Do Not Conform to Zone Boundaries. In terms of habitat preference, three groups of plants have distribution patterns whose ranges are difficult to predict. They are: aquatics, strand plants and alpine species. The last group requires almost perfect drainage, and it should be recalled that alpine conditions can occur at any altitude in arctic regions. Submersed aquatics are rare in the higher arctic, being virtually absent in zones 1 and 2. In the lower zones, aquatics tend to reverse the normal pattern of extending farther to the north in continental than in maritime areas. Many aquatic species which are normally confined to zone 4 reach well into zone 3 in both East and West Greenland. Many of the same species also occur in insular zone 3 areas such as St. Lawrence Island, Svalbard, and Novaya Zemlya. Examples are Sparganium hyperboreum, Potamogeton perfoliatus and Ranunculus aquatilis. A similar situation, although not as well marked, occurs with respect to semi-aquatic species such as Triglochin palustre, Equisetum palustre and Eleocharis acicularis. The explanation for this seeming anomaly is undoubtedly related to ice 106 STEVEN B. YOUNG conditions. The thickness of the ice and the duration of ice cover must be closely related to winter temperatures and snow cover. Areas with low winter temperatures and light snow cover have a shorter growing season for aquatic plants than do areas with moderate winter temperatures and a heavy snow cover, other factors being equal. The total depth of freezing must also affect the suitability of a pond or lake habitat for aquatic plants. Many aquatic species winter over by means of buds or roots under the ice. Probably few of these could survive in ponds which freeze solid. The ranges of arctic strand plants vary greatly, but many are similar in having a gap in their distribution along the arctic coast of Siberia, or in arctic Canada. With the exception of these gaps, many strand species conform well to zone boundaries. For example, Elymus arenarius, Honc- kenya peploides and Mertensia maritima have quite characteristic upper zone 3 distributions except that they are not known to occur along most of the northern coast of Siberia. The special distribution patterns of strand plants are probably due to two factors. First, their ranges are essentially linear, and the species cannot migrate along a broad front, which slows the populating of new areas. They are more likely to be trapped and elim- inated by climatic changes or advancing ice sheets than are terrestrial species. Also, strand plants are subject to physical disturbances by pack ice in much of the arctic. Long stretches of coast line on the Arctic Ocean are probably subject to such intense plowing action by ice each year that strand plants can never become established. “Alpine” plants do not form as clearly a defined group as aquatics and strand plants, but there are many arctic species which do not colonize areas where there is no significant topographical relief. The necessity for perfect drainage is a major factor in the distribution of these species. Most arctic regions have some mountainous or hilly and rolling terrain, and their floras include a large complement of alpine species. One exception is the northern part of the arctic slope in Alaska, an area about 500 miles long and over 100 miles wide. A large number of species are common throughout much of arctic Alaska, including the Brooks Range and St. Lawrence Island, but are absent from the northern part of the arctic slope. Examples are: Polygonum bistorta, Anemone narcissiflora, Cory- dalis pauciflora, Eritrichium species, Myosotis alpestris and Artemisia glomerata. Many of the alpine species are known to occur on Wrangel Island in zone 2, and some on the New Siberian Islands in northern zone 2 or even zone 1. Obviously, summer temperature is not an important factor in restricting these species from the arctic slope, most of which lies in zone 4. Other arctic areas with low relief are the Mackenzie Delta area, the Hudson Bay lowlands, the Yamal Peninsula and the northern part of the West Siberian lowlands, and some of the deltas of the major Siberian rivers, such as the Lena and Kolyma. Since several of these areas are where the arctic is reduced to a comparatively narrow coastal strip, it can be seen that these lowlands could act as important barriers to the spread of alpine plants in arctic regions. VASCULAR FLORA OF ST. LAWRENCE ISLAND 107 Many of the Beringean endemics are alpine species, as are others which are widely distributed in Eurasia, but reach North America only in Alaska. Other alpine species range from eastern Asia to Beringea and down the Rocky Mountains. The richness of the flora of the Beringean region and surrounding areas can be largely attributed to the fact that these areas were unglaciated during the Pleistocene and served as refugia for the arctic biota (Hultén 1937). Supposedly, many of the Beringean species formerly had a larger, possibly circumpolar, distribution but they have not recolonized all the areas from which they were eliminated during the glacial advances. It can also be hypothesized that many of the Beringean endemics and amphi-Beringean species do not have relict ranges; instead, they may be viewed as alpine species which originated in the great mountain complexes of central Asia and western North America. Both of these areas are con- nected to the Beringean region by continuous ranges of mountains which may be considered migration routes for alpine plants. However, from the Beringean region to other parts of the arctic these routes are blocked by lowland areas which are inhospitable to alpine plants, so that many of the Beringean alpine plants have not been able to colonize other alpine areas in the arctic. Thus, the present distribution of the Beringean plants may depend as much or more on currently acting ecological factors as on historical factors. In terms of distribution patterns, two groups of widely distributed species, whose northern limits of distribution do not conform well with the floristic zones, may be distinguished. One consists of species having a greater or lesser gap in an otherwise circumpolar range, but whose northern range limits conform well to the zone boundaries. The majority of species whose range is less than circumpolar belong to this group. Examples are Campanula uniflora and Dryas integrifolia. Campanula uniflora is not known throughout most of Siberia, but in all other parts of the arctic its northern limit is slightly north of the zone 2-zone 3 boundary. Dryas integrifolia is almost entirely confined to the North American arctic, but its northern limit there is almost exactly the zone 1-zone 2 boundary (Fig. 6). In Eurasia, D. integrifolia is replaced by the related but distinct D. octopetala (often treated as several related species, Porsild 1947). Where D. octopetala and D. integrifolia come in contact in North America, their habitat preferences differ, and they seldom hydridize. Dryas octo- petala conforms almost perfectly to the zone l-zone 2 boundary in Eurasia as does D. integrifolia in North America. A similar situation occurs in a number of other circumpolar complexes—for example, in the Cera- stium arcticum group, the Poa arctica group, and in parts of the genera Melandrium and Pedicularis. This indicates that plants tend to be con- servative with respect to their requirements for a critical amount of summer warmth. The ability of a species to expand its range northward beyond a certain limit is usually not subject to much geographic variation. The species in the group mentioned above do not constitute an exception 108 STEVEN B. YOUNG to the theory of floristic zonation and its relationship to amounts of avail- able summer warmth. These species have not attained a circumpolar range either because of historical or distributional factors, or because of the existence of replacement species in other parts of the range, but they still conform to zone boundaries throughout their ranges. However, there are a few cases in which a widespread, even circum- polar, species has a different northern limit in different sectors of its range. Rubus chamaemorus is a zone 3 species in most of the arctic, but it only reaches the southern tip of Greenland. Caltha palustris is a zone 2 species throughout Eurasia and western North America, but in the rest of North America it is a low arctic or subarctic species, not reaching Baffin Island or Greenland. Lathyrus japonica occurs in zone 2 and is common in zone 3 in the Beringean-Chukchi Sea region, but barely reaches zone 4 in Greenland, Labrador and western USSR. When a species has an anomalous distribution of this type, one of three explanations is possible. First, the distribution of the species may be con- trolled by a factor other than summer warmth, as has already been considered in the case of aquatics, strand plants and “alpine” plants. Second, the taxonomy of the group may be imperfectly understood, and a group treated as a single taxon may, in fact, include two taxa which are morphologically similar, but with different physiological characteristics. Finally, the anomaly may be due to historical and geographical factors, in the sense that the species under discussion have not become established throughout their potential range. There is no rule regarding which explanation, or which combination, applies in a given case. However, a few points can be made: first, one should determine whether the range of the species under consideration is unique, or whether there is a group of species with a similar distribution pattern. If it is found that several species share the same distribu- tional pattern, the next step is to decide whether the species are related taxonomically or ecologically, or whether the only relationship is simi- larity of the ranges. If the group of species has a specialized habitat requirement, it is probable that this is the main factor causing the anomalous distribution pattern. This has been discussed under aquatic plants above. If the group is taxonomically related, the anomalous distribution pattern may be due either to historical factors or to specialized requirements of the members of the taxon involved. If the group to which the species belongs has a major center of radiation which is presently evident, it can be concluded that the group is probably relatively young, rapidly evolving and has not yet fulfilled its potential range. Thus the anomalous distribution patterns are probably largely related to historical factors. Good examples are the genera Pedicularis and Primula. Both of these have centers of radiation in the mountains of eastern Asia, and their arctic representatives tend to be clustered in the Beringean region. There is little doubt that many species of these genera have only recently VASCULAR FLORA OF ST. LAWRENCE ISLAND 109 migrated to the arctic and they can be expected to increase their range in the future. But if the taxonomically related species with anomalous distribution patterns belong to more or less uniformly distributed groups, it may be that the anomalies are related to some unique physiological feature of the group. It is difficult to apply experimental evidence to this problem, and there are no examples of such a situation. It is interesting to note that a number of genera of Umbelliferae that are normally not found north of the temperate zone occur commonly in arctic parts of the Beringean region, indicating that perhaps many Umbelliferae find some necessary but unknown habitat requirements in the Beringean region. If the group of species under discussion shows no relationship, either in terms of habitat requirements or taxonomy, then it is reasonable to con- clude that historical factors are responsible for the distribution pattern. ON THE PHYSIOLOGICAL EFFECTS OF LOw AMOUNTS OF SUMMER WARMTH There is an important correlation between the northern limits of the ranges of arctic plants and the amount of warmth available during the summer. However, there is virtually no direct evidence regarding the cause. It is well-known that temperatures (and other climatic factors ) vary considerably between the immediate environment of arctic and alpine plants and the altitude at which temperature readings are com- monly taken (cf., Bliss 1962). Therefore, the correlation between a and the northern limit of a given species is not direct, but depends on an assumed correlation between a and a critical amount of warmth available to the plant. The actual physiological responses of plants to critical amounts of warmth are unknown and will continue to be so until laboratory experi- ments on the physiology of the plants in question have been carried out. However, field observations indicate that there are certain concepts and lines of investigation which should prove fruitful. We can hypothesize that the reproductive phase of the life cycle of a plant is the most sensitive to critically low amounts of warmth, either in the production of propagules or their germination. Obviously, a species cannot be considered fully established in an area unless it is capable of completing the entire re- productive cycle. However, individual invaders, capable of completing the germination phase only, could persist in quantity, depending on the number of propagules arriving at the area in question, and the life span of the plants. There are examples, in the St. Lawrence Island flora, of species which can be found in quantity in certain locations, but field observations indicate that they do not normally produce viable seeds or other propa- gules. Lycopodium clavatum, Epilobium angustifolium and Linnaea borealis, although each is known to occur at several stations on St. Lawrence, have not been observed to produce any reproductive structures 110 STEVEN B. YOUNG but their vegetative growth is apparently normal. Other species produce normal appearing flowers, but were never observed to set fruit. Rubus arcticus and Cornus suecica are examples. These species are usually found in rather large but rare and widely scattered colonies, each of which is probably a clone resulting from the germination of a single propagule originating on some mainland area. Of particular interest is Potentilla palustris. This species is fairly common in tundra pools over most of St. Lawrence, but it has been observed in flower only along a few river banks on the south side of the island. Apparently conditions here are near the critical limit for its reproduction. Propagules from the few reproductive stations on St. Lawrence or from the mainland probably are spread to other parts of the island by waterfowl. The peripheral populations of P. palustris survive only because of an influx of propagules from an outside source, or perhaps because of a long life span. Although tundra vegetation is of low and predominately herbaceous growth, it is evident that the life spans of individual tundra plants and clones are often very long. There is little direct evidence regarding the life span of the tundra plants, but it seems appropriate to consider the tundra vegetation as being a dwarf forest, rather than as an assemblage of short-lived annuals and perennials. Of the 238 species known to occur on St. Lawrence Island, only two, Koenigia islandica and Montia fontana, are true annuals. The only known colony of Dryas integrifolia on the island is almost certainly the one from which Chamisso collected speci- mens in 1816. We can only speculate on the life span of a clump of plants of a given species such as Carex aquatilis, but there can be little doubt that it is measured in tens if not hundreds of years. The long life span of many tundra plants means that there is no necessity for them to be able to reproduce every year. It is possible that many of the species could actively extend their range into areas where conditions allowed sexual reproduction (or other reproduction which produced dispersible propagules) to take place only once in a decade or even less. Therefore, it appears that if the ability to produce propagules is the main barrier to be crossed by a species in becoming established in a new arctic area, and if this ability is combined with a critical amount of warmth during the growing season, then the operating factor is not necessarily the mean amount of warmth over a period of years, but the likelihood that the critical amount of warmth necessary for the production of propagules will be reached during one or more growing seasons during the life of the plant. A similar situation would occur in the case of a species whose barrier was the germination of the propagule. Here, the probability of the propagule establishing itself would depend on a combination of the propa- gule landing in the target area, and conditions for germination being met during a given year. A third factor, of course, would be the length of time the propagule could remain alive but dormant until the proper conditions were available. This offers a reasonable explanation for the presence, on VASCULAR FLORA OF ST. LAWRENCE ISLAND 111 St. Lawrence, of a number of zone 4 species. The close proximity of the island to a good source of propagules of zone 4 species makes it likely that they will be available when the conditions necessary for germination occur. Isolated zone 3 areas, such as those of Spitzbergen and Ellesmere Island, would have little likelihood of having viable propagules of marginal species available when conditions were suitable for germination. If the factors that limit the establishment of arctic plants beyond their ranges are a matter of exceptional, rather than average, conditions, does this invalidate the concept that the presence or absence of a given species in a given area can be predicted on the basis of a, a figure derived from mean values? We can only say that the correlation between a values and the ranges of arctic plants is demonstrably significant. If exceptional conditions govern the ranges of species, then average conditions, as ex- emplified by a, offer a good index of the probability that the required exceptional conditions will occur often enough to allow species to become established in a given area. SoME IMPLICATIONS OF FLORISTIC 7ZONATION IN THE ARCTIC Since the floristic zone to which an area belongs is correlated with a rather specific amount of summer warmth, if the zone to which an area belongs is known, a reasonable estimate can be made of the summer temperature regime of an area. For example, Jan Mayen Island, which lies at about 72° N off the east coast of Greenland, supports a depauperate flora consisting of 62 species. This estimate is based on the rather liberal treatment of Lid (1964). Therefore, it might be expected that the island would fall into one of the contains a number of species that are definitely not typical of upper zone 2. Carex Lachenalii, Luzula arcuata, Honckenya peploides, Cassiope that the presence of a few species which reach only the lower edge of zone 3 indicates that the island is near the border between zones 4 and 3. The depauperateness of the flora is related to isolation, not climate. Because the aggregate of mean monthly temperatures above freezing for zone 3 areas usually lies between 12° and 20° C, we should expect the figure for Jan Mayen to be near 20° C. The island is obviously subject to a maritime climate, therefore we may expect that the highest mean monthly temperatures will occur in August rather than in July, that it will be comparatively low for a zone 3 area, and that the period of time during which temperatures average above freezing will be comparatively long. Climatic data from Jan Mayen (Walter 1960) show that the prediction made above is quite accurate. The mean monthly temperature for the 112 STEVEN B. YOUNG warm months is as follows: May 0° C; June 3°; July 5°; August 6.5°; September 4°; October 1°. The aggregate temperature (a) is therefore 19.5° C. It is remarkable how accurate an estimate of the summer temperature regime can be made on the basis of floristic data. The close agreement between the predicted and observed temperatures on Jan Mayen indicates that accurate predictions can be made even on the basis of a small and abnormally depauperate flora. One might expect that a similar prediction could be made in the case of a Pleistocene or Recent fossil flora even though the species represented in a fossil flora may be only a fraction of those present in the original flora. In practice, there are two difficulties involved in making predictions of this sort. The first is that most fossil floras known from the Pleistocene in the arctic are known from pollen studies. Pollen is often identifiable only to the generic level, and relatively few of the common genera in the arctic flora are of much use in defining zone boundaries unless the exact species is known. Therefore, predictions would often be based on minor elements in a pollen flora, sometimes without considering that rare pollen grains might have been blown in from another area or been redeposited from older strata. To make an accurate estimate of the zone to which an ancient flora belongs, one should really have the actual remains of plant bodies. The second difficulty is that the lowest zone to which the flora could belong cannot be determined with certainty using only a small portion of a flora. The presence of several zone 3 species in a fossil flora indicates that the flora must have been in a zone no higher in the arctic than zone 3, but it does not prove that the flora may not have been a typical zone 4 flora. In spite of these difficulties, preliminary studies indicate that the cor- relation of fossil floras with the zones proposed in this paper is possible in some cases. There also seems to be good reason to believe that in many areas the identifiable remains of plants may be recovered from per- manently frozen ground. With fossil floras of this type, the major dif- ficulties which arise when only pollen is studied are not applicable. Distribution patterns which superficially appear to be anomalous and for which complicated historical explanations have been proposed are often easily understood when the concept of zonation is applied. The St. Lawrence Island flora is a good example. One would be hard put to find a good historical explanation for the depauperateness of the flora, but the situation is readily comprehended when it is realized that St. Lawrence is in a different floristic zone than the adjacent mainland. A complementary example is in the flora of the Svalbard archipelago. Svalbard is an isolated group of islands lying between 75° and 80° N. Nearly all of the several land areas are presently glaciated. Nevertheless, the Svalbard archipelago supports a vascular flora of 155 to 160 species (Roénning in Love & Love 1963). Nearly all of these occur in the relatively VASCULAR FLORA OF ST. LAWRENCE ISLAND 113 small area in West Spitzbergen known as the Inner Fjord District, and many occurring there are not known elsewhere in the archipelago. The rich flora of the Inner Fjord District is in sharp contrast to the poor flora of such nearby areas as Franz Josef Land, which, as men- tioned above, supports only 36 species. Because of its richness, it has often been suggested that the flora of Svalbard is largely a relict flora, and that unglaciated refugia must have existed there at least during the last glacial period of the Pleistocene. However, it is difficult to understand how this could have been the case, for even at the present time some 90 per cent of the land area of the Archipelago is covered by glacier ice. An examination of the composition of the flora of Svalbard shows that most of the archipelago supports a typical zone 2 flora which includes some 100 species. The Inner Fjord District supports some 50 additional species. The vast majority of these are zone 3 species, many having typical circumpolar ranges, although in Svalbard they are confined to one small area. In short, the Inner Fjord District is simply a small “island” of zone 3 which is more or less surrounded by zone 2. It will be noted that the summer temperature regime for Barentsberg, Svalbard is exactly what could be expected in a zone 3 area, and is, in fact, similar to that of St. Lawrence Island. The rich flora of the Inner Fjord District is not at all anomalous when compared to other zone 3 areas, and there is no need to propose a theory involving an unglaciated refugium in the area to explain the situation. The only historical aspect of the situation is that the flora is somewhat more depauperate than many other zone 3 floras, which is easily understandable in view of the isolation of the area and the prob- ability that it has recently been glaciated. LITERATURE CITED ABBE, E., 1948. Braya in Boreal Eastern America. Rhodora 50: 1— BENSON, L., 1948. A Treatise on the North American oe Amer. Midl. Nat. 40: 1-261. aeaenstaseennerssapinas 1954. Supplement to a Treatise on the North American Ranunculi. Amer. Midl. Nat. et 328-369. Buss, L. C., 1962. Adaptations of Arctic and Alpine Plants to Environmental Condi- tions. Arctic 15: 117-144. Boécuer, T. W., 1956. Further Studies in Braya humilis and Allied Species. Meddel. om Grgnland Sal (7): 1-29. Bowven, W. M., 1957. 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Tormartcuey, A. L., ig Obzor Flory Novoi Zemli. Arctica 4: 143-178. ——-———— 1960-1966. Flora Arctica URRS. 1960: I: Polypodiaceae-Butomaceae. Moscow: 101 pp: "1088; IV: Lemnaceae-Orchidaceae. Moscow: 95 pp. 1964: I: Gramineae. Moscow: 272 pp. 1966: III: Cyperaceae. Moscow: 174 pp. 1966b: V: Salicaceae-Portulacaceae. Moscow: 207 pp. Waxter, H., 1960. Klimadiagram Weltatlas. Gustav Fischer, Jen Wiccrns, I., “ann J. H. Tuomas, 1962. A Flora of the Alaskan Arctic Slope. Toronto: 2 4 Youns, S. B., eee the ey of Vaccinium uliginosum L. In press: Rhodor: 1969. Contributions to the Ethnobotany a Saint ka. < Taewwenee ss Toles Aulapdlogiod papers of the University of Alas CHROMOSOME NUMBERS OF CRUCIFERAE. II.* Reep C. ROLLINS AND Lity RUDENBERG Along with general taxonomic research on the Cruciferae of the Western Hemisphere and more intensive revisionary studies of particular genera, a continuous program of chromosome counting and breeding system testing has been underway for some years. In many cases, seeds have been ob- tained from wild sources and plants were grown in the greenhouse to provide either root-tips or flowering buds for chromosome counting. Otherwise, fixations of bud material have been made in the field. The distinction between greenhouse collections and field collections is made where the data are presented. In all instances, voucher specimens were prepared and deposited in the Gray Herbarium. The most significant immediate problem in which chromosome number information is helping to establish a measure of understanding concerns certain taxonomically complex species groups of Arabis. The initial break- through came from the work of Bécher (1951) in which he established the presence of apomixis in the genus. In subsequent studies (Bécher 1954, 1969), evidence for widespread apomixis in Arabis was increased and the frequent association of asymmetrical chromosome numbers with apomixis was established. Facultative apomixis appears to be the rule. Previous studies by one of us (Rollins 1941, 1966) support the general assumption that several agamic complexes exist in the genus. The addi- tional chromosome counts presented below further add to the overall evidence for this assumption. In the following lists, the somatic counts from root-tips, or occasionally from some other somatic cell, are given as 2n, and those from pollen mother cells or immature pollen grains (microsporocytes ) as n. Arabidella A. trisecta (F. Muell.) O. E. Schultz n =12: plants from seeds of D. J. E. Whitley 2490. Far northeastern South Australia. To our knowledge, this is the first report of a chromosome count in the genus Arabidella. Arabis A. breweri Watson var. breweri 2n = 14: plants from seeds of Heckard, Constance & Ornduff 2319, Shasta Co., California. 1 The first paper in this series was published in Contrib. Gray Herb. CXCVII: 43-65. 1966. Some of the field work involved in this research was supported by funds from National Science Foundation Grant GB5872 to the senior author. 118 ROLLINS AND RUDENBERG A. constancei Rollins 2n = 14: plants from seeds of Constance & Chuang 3875, Plumas Co., California. A. holboellii Hornem. var. pinetorum (Tidestr.) Rollins 2n = 21 + 1: plants from seeds of Constance & Chuang 3876, Plumas Co., California. A. inyoensis Rollins 2n = 21: plants from seeds of Reveal & Beatley 1475, Lincoln Co., Nevada. Plate I, fig. 1. 2n = 23: plants from seeds of Beatley 9454, Nye Co., Nevada. A. perennans Watson n = 7: Coconino Co., Arizona, Rollins 6765. A. pulchra Jones var. pulchra 2n — 14: Kane Co., Utah, Rollins 6786. A. pulchra Jones var. munciensis Jones 2n = 21: plants from seeds of Beatley & Bostick 4048, Nye Co., Nevada. Plate I, fig. 2, fig. 4. A. pulchra Jones var. gracilis Jones 2n = 21: plants from seeds of Beatley 8829, Nye Co., Nevada. A. sparsiflora Nuttall var. subvillosa (Wats. ) Rollins 2n = 21, 2n = 21 + 1B, 2n = 22: plants from seeds of Al-Shehbaz 6950, Siskiyou Co., California. Plate I, fig. 3. Arabis breweri is in the A. sparsiflora complex of species in which Bocher (1969) has reported evidence of apomixis, The chromsome num- bers of the group as a whole seem to be based on n = 7 to which A. breweri conforms. Many of the populations of A. breweri appear to be relatively stable morphologically. The plants studied are of this sort and the chromosome number is uniform. In contrast, the cytological picture in A, sparsiflora var. subvillosa is very suggestive of an apomictic situation and helps to strengthen the evidence that apomixis is present and perhaps even widespread in A. sparsiflora. Surprisingly few chromosome counts have been published for A. sparsiflora when one considers the great abundance of plants and wide distribution of the species. Raven et al. (1965) published n = 22 for A. sparsiflora var. californica, and Bécher (loc. cit. ) reported 2n — 23 for A. sparsiflora var. atrorubens and the same number for A. sparsiflora var. columbiana. Although these numbers deviate slightly from an exact multiple of n = 7, as do some of our counts, it is clear that an agamic complex, such as this seems to be, can readily accomodate such deviating and asymmetric numbers. Our most recent count of 2n = 21 + 1 for A. holboelii var. pinetorum on California material along with previous counts of 2n = 21 on plants from Wyoming (Rollins 1966) and n = 14 and n — 21 on plants of Colorado (Rollins 1941a) shows that an unusual chromosome-number pattern is geographically widely dispersed within A. holboellii as a whole. This species is part of, and more or less at the center of, an agamic com- plex of species. CHROMOSOME NUMBERS OF CRUCIFERAE 119 Arabis inyoensis is a taxonomic puzzle mainly because no two collec- tions seem to match even in the most obvious details. We have attempted to see if the various specimens we have referred to A. inyoensis could be accounted for by hybridization between different taxa of Arabis in the area where it occurs. However, it has not been possible to assign putative parental taxa that would satisfactorily explain the specimens placed together under the name A. inyoensis. We recognize that the populations represented by our specimens are somewhat variable and that these have some features in common with A. pulchra var. munciensis. Arabis inyoensis was shown to be self-compatible by isolating individual plants and mechanically self-pollinating specific flowers. When this procedure was followed, a good seed-set resulted. In isolated plants, emasculated flowers with no chance for pollination still produced a limited seed-set. From 96 ovules, seven viable seeds arose. Thus, approximately 7.3 per cent of the ovules matured into seeds without fertilization or even pseudogamy. This is strong evidence that apomixis is operative in A. inyoensis. The chromosome number of 2n = 21 in Arabis pulchra var. munciensis and in var. gracilis and of 2n = 21 and 2n = 23 in A. inyoensis, strongly suggests the possibility of another complex of apomicts in the group of species associated with A. pulchra. In Plate I, fig. 1, trivalent and tet- ravalent chromosome associations, as well as univalents, are clearly shown. If these data were to be coupled with definite evidence of inter- specific hybridization, an adequate basis for explaining the peculiar variability to be seen among the specimens would surely be established. Arabis pulchra var. pulchra is a stable taxonomic entity when compared with var. gracilis and var. munciensis, the latter being quite variable. On the basis of our present knowledge of the species, we would predict that var. pulchra with its chromosome complement of 2n = 14 is sexual and that var. gracilis and var. munciensis are largely apomictic. Cakile Three collections of seeds of Cakile, one from Duval Co., Florida, one from Monroe Co., Florida and one from St. John Beach, Trunk Bay, Virgin Islands, have been supplied to us by Dr. C. E. Wood, Jr. Plants from these have been grown and a chromosome count on each proved to be 2 n — 18, This material was turned over to Mr. James E. Rodman who has now undertaken a major study of the genus Cakile as it occurs in the Western Hemisphere. He will report on the identity of the material re- ferred to and more fully on the cytology at a later date. Caulanthus C. cooperi ( Wats.) Payson n = 14: Inyo Co., California, Rollins 6715; 6737; 6752. n — 14: Kern Co., California, Rollins 6726, Plate I, fig. 5. 120 ROLLINS AND RUDENBERG Fic. 1, PMC, diak Arabis inyoensis, Reveal & Beatley 1475. Fic. 2, root-tip cell, P @ var. munciensts, Beatley & Bostick ott Fic. 3, root-tip cell, Arabis sparsiflora var. subvillosa, Al-Shehbaz 6950. Fic. 4, same as fig. Fig. 5, PMC. half of A,, Speier cooperi, Rollins 6726. Fic. 6, PMC, diak., Cadaitinds ates Rollins 6731. All figures & ca. CHROMOSOME NUMBERS OF CRUCIFERAE 121 C. coulteri Watson n = 14: Kern Co., California, Rollins 6724, Plate II, fig. 8. C. glaucus Watson n = 10: Inyo Co., California, Rollins 6736, Plate II, fig. 7. C. inflatus Watson n — 14: San Bernardino Co., California, Rollins 6731, Plate I, fig. 6; Rollins 6754. C. inflatus (?) n = 14, 2n = 28: plants from seeds of Al-Shehbaz 6945. San Bernar- dino Co., California. C. lasiophyllus (H. & A.) Payson var. lasiophyllus n = 14: Inyo Co., California, Rollins 6714. n =14: Kern Co., California, Rollins 6722. n — 14: San Bernardino Co., California, Rollins 6732. n = 14: plants from seeds of Al-Shehbaz 6948, San Bernardino Co., California. Four different populations of Caulanthus cooperi were sampled by fixing buds in the field. Some irregularities and some stickiness was seen, but a consistent chromosome number of n = 14 was found in all populations. This number is in line with that of most other species of Caulanthus and adds some evidence which favors the inclusion of the species in this genus. The flowers of C. cooperi are “streptanthoid” which also suggests that Payson was correct in placing it in Caulanthus. The finding of n = 10 in C. glaucus was a surprise because we had come to expect n = 14 in the uncounted species of the genus. To be sure, we had earlier reported n = 10 for C. inflatus, but our most recent counts, which have been double-checked, show the count for C. inflatus to be n = 14. A collection, Al-Shehbaz 6945, has been tentatively referred to C. inflatus. The green- house-grown plants differ from specimens of wild populations in a number of significant ways and the material may represent a different taxon. There is no doubt about it being Caulanthus, but whether the material should be called C. inflatus is somewhat open to question. A specimen has been placed in the Gray Herbarium for further reference. Cardamine C. flaccida Chamisso & Schlechtendahl n = 8: plants from seeds of Meyer 9589, Mas Atierra, Juan Fernandez Islands, Chile. As currently interpreted, Cardamine flaccida is a highly variable species with a geographic range that extends through much of the Cordilleran region of South America, and northward into Mexico. It is doubtful whether all variants now placed in this species are in reality a single taxon of specific rank. For this reason, the identity of the material studied is somewhat open to question and may need to be changed once the tax- onomy of C. flaccida and its near relatives has been fully worked out. The chromosome number fits with that of a number of North American species 122, ROLLINS AND RUDENBERG as reported by Mulligan (1965) as well as many species from elsewhere (Manton 1932). Descurainia D. pinnata (Walt.) Britton subsp. halictorum (Cockerell) Detling = 7, 2n = 14: plants from seeds of Moran 12500, La Bocana, Baja California, Mexico. Greenhouse-grown plants of this taxon proved to be not only self- compatible but strongly autogamous as well. With insects excluded and without any manipulation whatever, a full set of fruits and seeds were produced. Draba D. asprella Green n — 16+: Coconino Co., Arizona, Rollins 6766. D. brachycarpa Nuttall 2n = 24: plants from seeds of D. S. & H. B. Correll 36897, Kaufman Co., Texas. D. corrugata Watson var. demareei (Wiggins) C. L. Hitchcock n —12: plants from seeds of Moran 15267, San Pedro Martir Cerro, Baja California, Mexico. Plate III, fig. 12. D. cuneifolia Nuttall n = 16: plants from seeds of D. S. & H. B. Correll 30840, Pecos Co. Texas. D. platycarpa Torrey & Gray n = 16, 2n = 32: plants from seeds of D. S. & H. B. Correll 30763, Kinney Co., Texas. The morphological distinctions between Draba cuneifolia and D. platy- carpa are sharp and consistent. However, D. platycarpa has often been treated as a variety of D. cuneifolia. For this reason, having material of both taxa available for study, we looked at the chromosomes and chromo- some number with special interest. The number and general size relation- ships of the chromosomes of both species are similar. Nothing definitive either supporting the presently accepted taxonomy or suggesting the recognition of two infraspecific taxa could be seen in the chromosomes. Dithyrea D. californica Harvey n = 10: San Bernardino Co., California, Rollins 6702; 6703, Plate III, fig. 13 & 14. D. wislizenii Engelmann n = 9: Coconino Co., Arizona, Rollins 6777; Washington Co., Utah, Rollins 6789, Plate II, fig. 9. 2n = 18: Navajo Co., Arizona, Rollins 67115, Plate II, fig. 11. The above chromosome numbers are the same as those previously CHROMOSOME NUMBERS OF CRUCIFERAE 123 reported (Rollins 1966) and serve to confirm that the aneuploid relation- ship between Dithyrea californica and D. wislizenii is consistent taking different populations and a broadened geographic area into account. In the three populations of D. wislizenii sampled, all plants possessed densely pubescent siliques. However, in one population 38 miles east of Kanab, Kane Co., Utah (Rollins 6784) not fixed for cytological sampling, an examination of 100 plants at random showed 47 plants with glabrous fruits and 53 plants with pubescent fruits. This approximate 1:1 ratio of glabrous- to pubescent-fruited plants is different from the population previously analyzed (Rollins 1958) which was roughly 1:3 glabrous to pubescent. The experimental data from crosses involving glabrous- and pubescent-fruited plants showed that a 1:1 ratio resulted when heterozygous glabrous-fruited individuals were crossed with homozygous pubescent-fruited individuals. That wild populations with this same ratio of glabrous to pubescent fruits existed could have been confidently pre- dicted, but this is the first confirmation that such populations are, in fact, to be found in nature. The chromosomes of the somatic cell of Dithyrea wislizenii shown in Plate II, fig. 11, were stained with both Feulgen and acetocarmine which produced a more intensely refractive photographic image than is usual. The difference in size between A, and M, chromosomes is ordinarily great. However, in D. californica, the difference is unusually large as is shown in Plate III, fig. 13 and 14. Dryopetalon D. runcinatum Gray var. laxiflorum Rollins n = 12: plants from seeds of D. E. Breedlove 15892, Municipio Mocorito, Sinaloa, Mexico, Plate II, fig. 10. This is the first chromosome number report for Dryopetalon which is a relatively small genus of southwestern United States and northwestern Mexico (Rollins 1941b). Flowers of living plants show the white petals to be oriented in a paired upper and lower position and with the anthers of all stamens introrse. The stigma is definitely bilobed. Erysimum E. moranii Rollins 2n = 36: plants from seeds of Moran 15116, Guadalupe Island, Baja California, Mexico. E. suffrutescens (Abrams) Rossbach var. lompocense Rossbach n = 18: San Luis Obispo, California, Rollins 6727. The plants grown from Moran 15116, the type number of the species, are subshrubby and very much branched. The species was only recently described (Rollins 1970). The chromosome complement in Erysimum moranii is unusual in that the chromosomes differ greatly in size. The 124 ROLLINS AND RUDENBERG e Il. Fic MC, diak., Caulanthus glaucus, Rollins 6736. Fic. 8, PMC, half of A, irae cour sadoaig 6724. Fic. 9, PMC, half of A_, Dithyre. in aeislionnll, ergy 6789. Fic. 10, P yopetalon runcinatum var. eee at ay, Sees 15892. Fic. 11, tapetal cell, Ditheres ce Rollins 67115. All figures X ca. 2650. CHROMOSOME NUMBERS OF CRUCIFERAE 125 * = = Til. Fic. 12, F Draba corrugata var. demareet, Moran 15267. Fic. 13, PMC, MC, A, oe w_Dithsrea ‘clone Rollins 6702. Fic. 14, PMC, M, Dithyrea — Rollins 6703. Fic. 4s. PMC, 1 te A,, Lepidium fremontii, Rollins 6707. All figures X ca. 2650. 126 ROLLINS AND RUDENBERG longest chromosome is nearly four times longer than the shortest chromo- some, and there are many different sizes in between. Lepidium L. flacum Torrey n = 16: Inyo Co., California. Rollins 6713. L. fremontii Watson n = 32: Clark Co., Nevada, Rollins 6707, Plate III, fig. 15; Inyo Co., California, Rollins 6717. L. lasiocarpum Nuttall n = 16: Clark Co., Nevada, Rollins 6706. L. montanum Nuttall var. canescens ( Thellung) C. L. Hitchcock 2n = 32: plants from seeds of Beatley 5998, Nye Co., Nevada. L. montanum Nuttall var. jonesii (Rydberg ) C. L. Hitchcock n = 32: Coconino Co., Arizona, Rollins 6781. L, virginicum L. 2n = 32: plants from seeds of Thieret 29936, Morehouse Parish, Louisiana. The two high polyploids (n = 32), Lepidium fremontii and L. mon- fanum var. jonesii are perennial and either shrubby as in the former or subshrubby as in the latter. Except for L. montanum var. canescens, the other taxa reported upon above are herbaceous annuals. From the data so far available (cf., Manton 1932: Mulligan 1961; Rollins 1966), it ap- pears that most of the herbaceous species of Lepidium in North America are either diploid or tetraploid based on x = 8. A notable exception is L. ramosissimum Nels. with 2n = 64 ( Mulligan 1961). Lesquerella L. arizonica Watson n = 5, 2n = 10: Coconino Co., Arizona, Rollins 6762, Plate IV, fig. 19. 2n = 10: Coconino Co., Arizona, Rollins 6776. n = 10: Coconino Co., Arizona, Rollins 67100. L. auriculata (Engelmann & Gray) Watson n = 8, 2n = 16: plants from seeds of Barclay 3058. Garfield Co., Oklahoma. L. cinerea Watson n = 5: Yavapai Co., Arizona, Rollins 67109, Plate IV, fig. 18; same county, Rollins 67110; Coconino Co., Arizona, Rollins 6770-prob- ably 2n = 10. L. douglasii Watson n = 5, 2n = 10: Lincoln Co., Washington, Rollins & M. Ownbey 6794. L. fendleri (Gray) Watson n = 6: McKinley Co., New Mexico, Rollins 67116. 2n =12: Sandoval Co., New Mexico, Rollins 67122; plants from seeds of Rollins & Correll 6616, Kinney Co., Texas. CHROMOSOME NUMBERS OF CRUCIFERAE 127 L, gordonii (Gray) Watson n = 6, 2n = 12: Mohave Co., Arizona, Rollins 6760. L. intermedia (Watson ) Heller n = 18: Mohave Co., Arizona, Rollins 6797. L. lindheimeri (Gray) Watson n = 6: near Matamoras Airport, Tamaulipas, Mexico, Rollins 6701, Plate IV, fig. 16. L, peninsularis Wiggins n = 24+: Sierra San Pedro Martir, Baja California, Mexico, Moran & Thorne 14379. L, pinetorum Wooton & Standley n = 5: Yavapai Co., Arizona, Rollins 67107. Plate IV, fig. 21. 2n —10: Bernanillo Co., New Mexico, Rollins 67119. Plate IV, fig. 20. L. rectipes Wooton & Standley n = 9, 2n = 18: plants from seeds of Gentry & Davidse 1794, San Juan Co., Utah, Plate IV, fig. 17. n = 20, uncertain count: McKinley Co., New Mexico, Rollins 67117. L. tenella Nelson 2n=— 10: Riverside Co., California, Rollins 6755. In a previous report on chromosome numbers in Lesquerella (Rollins 1966) polyploid populations were mentioned based on numbers of x = and x = 9, It is now clear that polyploidy occurs within L. arizonica which has a fundamental number of x = 5. The diploid, Rollins 6762, was collected within 20 miles of the tetraploid, Rollins 67100. Both populations were in an open pifion-juniper woods where limestone chip is prevalent. The previous report of 2n = 18 for L. intermedia and the present one of n = 18 also shows that polyploidy occurs in this species. It is probable that both of these records represent polyploidy based on the fundamental number x = 6 because the species most closely related to L. intermedia have n = 6. We are somewhat uncertain as to the number n = 24 for Lesquerella peninsularis because all figures showed some clumping of the chromo- somes. However, we can be certain that the species is a polyploid. The evidence also shows that L. rectipes has polyploid populations even though we were not able to obtain a certain count on the New Mexico population cited. The above citation is the first record of Lesquerella lindheimeri from Mexico. However, this species is characteristic of the coastal plain of extreme southern Texas and was to be expected from adjacent Mexico. The chromosome number n = 6 conforms to the number present in the Texas populations cited in an earlier paper (Rollins loc. cit.). Ornithocarpa O. torulosa Rollins n = 24, 2n = 48: plants from seeds of Breedlove 15888, Durango, Mexico. 128 ROLLINS AND RUDENBERG Prate IV. Fic. 16, PMC, A,, Lesquerella lindheimeri, Rollins 6701. Fic. 17. PMC, My) Lesquerella rectipes, Gentry & Day idse 1794, 8, i st div. Lesquerella Rollins = Fic. 1 cinerea, 67109. Fie.19, PMC, half of A somatic anther cell, Lesquerella age tige Rollins 9. Fie. 21, PMC, A, Rollins 67107. Fic. 22, PMC, dia k.—-M,, Physaria geyeri, Cues 3467. All figures X ca. 2650. CHROMOSOME NUMBERS OF CRUCIFERAE 129 * < Piate V. Fic. 23, young pollen grain, Physaria geyeri, Ownbe 3467. Fic. 24, young pollen grain or possibly PMC, Physaria chet Rollins 6788. Fic. 25, PMC, Ap esaagesegi am- iguum, Rollins 67101. Fic. 26, PMC, dia Sibara angelorum, Moran 12345. 27, root-tip cell, Pringlea antts iscorbutica, Montreal rag Ga rd. Fic. 28, root-tip cell, Seat ane subsp. inyoensis, Beatley 9010. All figures X ca. 2650 130 ROLLINS AND RUDENBERG Since publishing this species as new (Rollins 1969) and giving the somatic chromosome number of 2n = 48, we have examined the meiotic chromosomes and additional root-tip material both of which confirm the original chromosome number determination. Physaria P. chambersii Rollins n = 8: Washington Co., Utah, Rollins 6788, Plate V, fig. 24. P. geyeri (Hook.) Gray n = 4: Spokane Co., Washington, M. Ownbey 3467, Plate IV, fig. 22 and Plate V, fig. 23. The above tetraploid count for P. chambersii was to be expected on the basis of the data of Mulligan (1968) in which he showed that races with 2n = 16 predominate in southern Utah. Also, the count for P. geyeri is the expected number. Mulligan (loc. cit.) has transferred P. geyeri to the genus Lesquerella but we do not agree with this disposition of the species. The chromosomes of P. geyeri are much more like those of other species of Physaria than of any of the species of Lesquerella we have studied. This is clearly shown by comparing Plate V, fig. 23, showing the chromosomes of an immature pollen grain of Physaria with those of Lesquerella cinerea, Plate IV, fig. 18, also from an immature pollen grain. A full discussion of the issue will be presented in a forthcoming mono- graph of Lesquerella now in the late stages of preparation. Pringlea P. antiscorbutica R. Brown n = 24: plants from seeds received from the Montreal Botanical Garden. The original seeds from which the plants at the Montreal Botani- cal Garden were derived presumably came from a French expedition to the Kerguelen Islands. We have grown plants of this species for several years in the greenhouse, but we have not been able to bring them into flower. Our chromosome count is the same as the previous count given by Hamel (1951). Rorippa R. nasturtium-aquaticum (L.) Hayek 2n = 32: plants from seeds of Riidenberg s.n., Monterey Co., California. According to Green (1962), the watercresses are all introductions from the Old World. They are found widely distributed in the Western Hemi- sphere and often appear to be native. His map of distributions shows only R. nasturtium-aquaticum in California, the central and southerly states, and central and South America. Our material is obviously of the diploid R. nasturtium-aquaticum, not R. microphyllum which has 2n = 64 and has a more northerly distribution in North America. CHROMOSOME NUMBERS OF CRUCIFERAE 131 Selenia S. dissecta Torrey & Gray n =7: Brewster Co., Texas, Rollins & Correll 6633. S. grandis Martin n = 12: plants from seeds of Correll 36755, Hidalgo Co., Texas. Three species of Selenia have now been counted and no two appear to have the same chromosome number. The count of n = 12 for S. grandis reaffirms previous results on plants from Dimmit Co., Texas ( Rollins 1966). Arkansas material of S. aurea had n = 23. Selenia dissecta is very different morphologically from either one of these species. It is found only in New Mexico, extreme western Texas and adjacent Mexico. Sibara S. deserti (Jones) Rollins n = 14 +: Inyo Co., California, Rollins 6746. S. laxa (Watson) Greene n = 14: Sierra San Borja, Baja California, Mexico, Moran 12318. S. angelorum (Watson) Greene n = 14: Bahia de los Angeles, Baja California, Mexico, Moran 12345. Plate V, fig. 26. The previous chromosome count of 2n = 26 for Sibara deserti ( Rollins 1947) may be in error as judged by 2n = 28 for most other species of the genus. However, our present material was not well enough fixed for us to be certain. The new counts of n = 14 for S. laxa and S. angelorum are the first for these species. Sisymbrium S. ambiguum (Watson) Payson n = 11: Mohave Co., Arizona, Rollins 6796; Coconino Co., Arizona, Rollins 67101, Plate V, fig. 25. S. linifolium Nuttall n — 7: Kane Co., Utah, Rollins 6785. S. salasugineum Pallas [Thellungiella salsuginea (Pall.) O. E. Schultz] 2n = 14: plants from seeds of Weber 12925, Park Co., Colorado. We have followed Payson (1922) in the taxonomic placement of Sisymbrium ambiguum, but it is quite clear that this species should not be retained in Sisymbrium. The chromosome number of n = 11 supports this view and points to the possible association of S. ambiguum with s linearifolium which also has a chromosome number of n = 11 (Rollins 1966). An extra B-chromosome may be readily seen in fig. 25 of Plate V. Although S. salsugineum fits the pattern for Sisymbrium, this species is often placed in the genus Thellungiella. Our count is the same as the two counts listed in Bolkovskikh et al. (1969). 132 ROLLINS AND RUDENBERG Stanleya S. ei age Inyo Co., California, Rollins 6738. Plants from seeds of "ALS Se 6944, Inyo Co., California. S. pinnata (Pursh) Britton subsp. pinnata n = 14: Kane Co., Utah, Rollins 6787. S. pinnata subsp. inyoensis Munz & Roos: n = 28: Nye Co., Nevada, Rollins 6712; Inyo Co., California, Rollins 6747. 2n — plants from seeds of Beatley 9010, Nye Co., Nevada, Plate V, fi g. 2 S. oy Nuttall 2n = 28: plants from seeds of Al-Shehbaz 6938, Humboldt Co., Nevada. In the arid valleys of eastern California and nearby Nevada, Stanleya pinnata is subshrubby with a well-developed short, woody trunk. These populations were distinguished from the more widespread subspecies pinnata and named subspecies inyoensis by Munz and Roos. Evidently these more woody plants are polyploid if our sampling of three popula- tions is a fair indication of the situation in the subspecies as a whole. Our recent chromosome counts in Stanleya strongly indicate x = 14 as the fundamental number for the genus. Strepthanthella S. sSicgilaghies (Watson) Rydberg = 14: San Bernardino Co., California, Rollins 6705; Kern Co., California, Rollins 6725; Inyo Co., California, Rollins 6745; Clark Co., Nevada, Rollins 6709; Coconino Co., Arizona, Rollins 6782. n = 14, 2n =28: Washington Co., Utah, Rollins 6790 LITERATURE CITED Bocuer, T. W. 1951. Cytological and Embryological Studies in the Amphiapomictic Arabis holboellii complex. Dan. Biol. Skrifter 6, no. 7, 1-59. Cn — Taxonomical Studies i in the eel holboellii complex. eeaks ne Tidskr. 48: 31-44, 96! 9. aarti ‘ie in Arabis holboellii and Allied Species. Botan. Botknovskixn, Z. Er AL. 1969. Chromosome Numbers of Flowering Plants. V. L. Komarov Botanical Institute, Acad. Sci. USSR 1-926. GreEN, P. S. 1962. Watercress in the New World. Rhodora 64:32-43. Hamet, J. L. 1951. Note sur le Noyau et les Chromosomes Semen du Pringlea antiscorbutica R. Br. ex Hook.f. Bull. Mus. Natl. Hist. Nat. 23:54 Marrs, I. 1932. Introduction to the General Cytology of the eam Ann. Bot. Secnaciar A. 1961. The Genus Lepidium in Canada. Madrofio 16: 77-90 965. Chromosome Numbers of the Family Cruciferae II. Canad. Journ. Bot. 43: et a CHROMOSOME NUMBERS OF CRUCIFERAE 133 1968. Transfers from Physaria to Lesquerella. Canad. Journ. Bot. 46: 527-53 0. gag E. B. 1922. apes of Sisymbrium Native to America North of Mexico. Univ. o. Publ. Sci. 1:1-27. *”. H. ET AL. “1965. Chromosome Numbers of Spermatophytes, mostly Cali- gr aneliy Aliso 6: 105-113. Rouuins, R. C, 194la. A Monographic ae of Arabis in Western North America. Rhodo ora ba 289-325, 348-411, ae i Cruciferous sai Dryopetalon. Contrib. Dudley Herb., Stanford i 19 47. Generic Revisions in the Cruciferae: Sibara. Contrib. Gray Herb. 3-143. Bane: No. 165. 133- ——-—-~—— enetic Evaluation of a Taxonomic Character in Dithyrea 1958. The (Cruciferae). ‘Rhodora 60: 14 6. Chromosome Numbers of Cruciferae. Contrib. Gray Herb. Harvard. a ie 197. As 6 anteater 1969. A Remarkable New Crucifer from Mexico. Contrib. Gray Herb. Harvard. ee 198. 3-8. -_--———. 0. Notes on Srotcgercd a and Erysimum (Cruciferae). Contrib. Gray 190- Herb. Poa dy No. 200. Contributions from the RAY | HERBARIUM Te < 1971 NO. James W. POLLEN MORPHOLOGY, PHYTOGEOGRAPHY, Walker AND PHYLOGENY OF THE ANNONACEAE. EDITED BY Reed C. Rollins Kathryn Roby PUBLISHED B THE CRAY HERBARIUM OF HARVARD UNIVERSITY IssuED JuLy 30, 1971 Contributions from the GRAY HERBARIU 1971 Pi ates s fn nw ae POLLEN MORPHOLOGY, PHYTOGEOGRAPHY, AND PHYLOGENY OF THE ANNONACEAE! James W. WALKER® The Annonaceae is a moderate-sized family of flowering plants with approximately 130 genera and 2,300 species. Phytogeographically it is almost entirely tropical, with three main centers of distribution: the American tropics, tropical Africa, and the Asian tropics. Taxonomically it is quite distinctive with its rather primitive flowers typically having a three whorled, 3-merous perianth, numerous, extrorse, peltate stamens, numer- ous, distinct carpels, and seeds with ruminate endosperm. The primitive floral morphology is in sharp contrast to the more advanced wood anat- omy, with all members of the family constantly possessing vessel elements with simple perforations (Vander Wyk & Canright, 1956 ). Phylogenetical- ly, the Annonaceae were early recognized as primitive angiosperms with a close relationship to such families as the Magnoliaceae and the Myristicaceae. While there has never been any serious question concerning the inter- familial phylogeny of the family, there has never been a satisfactory infra- familial classification (cf., Sinclair, 1955; Fries, 1959; Hutchinson, 1964). All modern treatments of the family are rather artificial in that a single character of the floral morphology has been used to separate the family into two primary groups, the “Uvarieae” (with imbricate petals) and the “Unoneae” (with valvate petals). Attempting to understand the internal relationships of the family more clearly, the author made a preliminary survey of the pollen of some genera within the family and discovered not only that the pollen was often highly distinctive for certain genera, but that the pollen morphology of the taxa within the family was quite diverse and often indicative of relationships. The present study combines the results of an investigation of the pollen morphology of the family with data from floral morphology and phytogeography, hopefully to produce a natural infrafamilial classification of the Annonaceae and a better under- standing of its internal phylogeny. In the course of the present study a number of interesting discoveries were made—disulculate pollen, the primitive, distal aperture of Pseudo- xandra, the peculiar, giant polyads of Cymbopetalum, etc.—but none was more surprising to the author than the realization that evidence from both palynology and floral morphology was overwhelmingly indicative of a New World (and/or possibly African) origin for the Annonaceae, in contrast to the great majority of “ranalean” families, which are clearly of an Asian or Australasian origin. (It appears as if cytotaxonomic data also 1Revised version of a dissertation presented to the Department of Biology, Harvard University, in partial fulfillment of the requirements for the degree of Doctor of Philosophy. 2Present address: Department of Botany, University of Massachusetts, Amherst, Massachusetts 4 JAMES W. WALKER suggest a New World origin for the family, cf., Ehrendorfer et al., 1968. ) In the following, the floral morphology of the family is briefly surveyed. This is followed by a discussion of its pollen morphology and evolution, its phytogeography, and finally its phylogeny. The major discoveries made during the palynological investigation are listed in the summary at the end of the paper. FLORAL MORPHOLOGY The typical annonaceous flower consists of a calyx of three separate sepals; a biseriate corolla with six separate petals; numerous, spirally arranged, extrorse, peltate stamens; an apocarpous gynoecium of numer- ous, spirally arranged carpels with many to one ovules; baccate, more or less stipitate fruits; and seeds with a small embryo and an abundant, ruminate endosperm. There are, however, a number of interesting varia- tions of this pattern within the family. Some genera have unisexual flowers; others may have lost one of the two whorls of petals, the six petals may be reduced to four, or the six may be in one whorl and be fused. Some genera have stamens that are not peltate, sometimes the stamens are few and whorled, or rarely staminodia are present as in Uvaria, Anaxagorea, and Fusaea. In some genera the carpels may be reduced to one, while in others they may be fused into a unilocular, compound pistil or multi- locular syncarp. Very rarely the fruit may open at maturity, either as a dry follicle or as a ventrally or laterally dehiscing berry. Some genera have arillate seeds, while in the genus Richella, the seeds are winged. The most important recent papers dealing with the floral morphology of the family include Fries’ revisions of the New World Annonaceae (1930-39), Sinclair's revision of the Malayan members of the family (1955), and the treatment of the Annonaceae by Le Thomas in the Flore du Gabon (1969). Floral characters that are particularly valuable in the classification of the family include peduncle bracts, inflorescence type and position, aestivation and nature of the petals, nature of the stamens, ovule number, and fruit The peduncles of almost all members of the family are articulated ( Deeringothamnus lacks an articulation). The bracts on the peduncle may be found in three basic arrangements: (1) bracts both above and below the articulation; (2) bracts only below the articulation; and (3) peduncle ebracteate. The inflorescence may be axillary, leaf-opposed, terminal, supra- axillary, extra-axillary, or cauliflorous. Inflorescence position often has been used to separate closely related genera. The imbricate versus valvate aestivation of the petals has been used classically to divide the family into two primary groups. However, it is quite evident that valvate petals have arisen independently within the family many times in different lines and that any basic separation of the family into two groups based solely upon petal aestivation is highly ANNONACEAE 5 artificial The shape of the petals varies considerably, ranging from rounded to strap-shaped and even to clawed and mitriform. From char- acter correlation it appears that the primitive petal shape is round, as in such putatively primitive genera as Cremastosperma and Malmea (cf., Diels, 1932). The texture of the petals is of some classificatory usefulness, e.g., Hexalobus, Monodora, and Asimina have membranous, often wrinkled petals, while the petals are thick and fleshy in Annona and related genera and in Cymbopetalum and its allies. The staminal connectives have been used classically to order the genera into tribes. The most common type of stamen in the family is strongly peltate and its prevalence led Hutchinson (1964) to state that the “truncate anther-tips are a very striking feature of the Annonaceae, and they may represent an ancient relict type of leaf-structure.” However, the primitive stamen type in the family is not peltate, as evident from the morphology of the microsporophylls in the genus Anaxagorea, clearly the most primitive type of stamen extant in the Annonaceae. In the least specialized species of the genus, A. costaricensis, the stamens are very laminar and leaf-like with a definite, stalk-like, basal section (pl. 20:1). The locules are widely separated (pl. 21:2) and the vascular trace terminally bifurcates and then recurves to bifurcate a second time (pl. 21:1). The overall appearance of these stamens is remarkably similar to those of Degeneria. However, it should be noted that, unlike the Magno- liaceae and Degeneriaceae, all stamens examined in the Annonaceae constantly exhibited a single trace (pl. 20:1). Anaxagorea costaricensis is the only exception because a few stamens in a flower may rarely have islands of vascular tissue. This undoubtedly represents the vestigial re- mains of the two lateral traces (pl. 20:2). In addition to other primitive features of the stamens of Anaxagorea is the occurrence, in several differ- ent species, of stomata on the abaxial, staminal surface (pl. 19:7-8). The non-peltate stamens of other genera are probably secondary (e.g., Miliusa, Orophea). They are clearly secondary in the advanced, West Indian species of Annona. However, the non-peltate stamens in Oxandra may represent a primitive feature inasmuch as the genus has sulcate pollen and is found in the otherwise primitive Malmea tribe. A number of genera within the family are characterized by transversely septate anther locules at maturity. In this connection, it is interesting to note that some genera have rudimentary, sterile septa that are lost as the stamen matures (Cananga, Monodora, Asimina, and Annona—cf., Davis, 1966). The low ovule number in a number of otherwise primitive genera (Cremastosperma, Malmea, Pseudoxandra, Anaxagorea), as well as the relatively few ovules in the closely related and generally less specialized family Magnoliaceae, argues for a low, basic ovule number for the family, with the possibility that a high ovule number may be secondary. Even assuming this, it is still clear that some genera may have secondarily acquired a low ovule number, e.g., Annona. 6 JAMES W. WALKER The overwhelming majority of the genera in the family have the apocarpous gynoecium developing into numerous, berry-like fruits. Anaxagorea, however, is unique with its dry, dehiscent follicles containing two seeds. They probably represent a primitive type within the family and are reminiscent of the fruit type in the Magnoliaceae. It might be noted that the related, but more specialized genus, Xylopia, has ventrally dehiscent, baccate fruits, possibly representing an intermediate fruit type between the follicles of Anaxagorea and the true indehiscent, baccate fruits of the great majority of the genera, as exemplified by Cananga. The fruit of Cymbopetalum is highly specialized in that it opens laterally, not along the ventral suture as in Xylopia, thus exposing its numerous, arillate seeds. The aril-covered seeds of Cymbopetalum and related genera are clearly highly specialized within the family and cannot be considered primitive. POLLEN MORPHOLOGY Previous PALYNOLOGICAL STUDIES Earlier studies generally included information on pollen as a matter of secondary interest. Mueller (1865-66) in his Fragmenta Phytographiae Australiae included illustrations of the pollen grains of Ancana stenopetala—Fissistigma in a plate along with flowers and fruits. Le Maout and Decaisne clearly illustrated a tetrad of Asimina triloba in their System of Botany (1876). Miquel, in Martius’ Flora Brasiliensis (1856), evidently was the first to picture an annonaceous polyad as part of his plate of the genus Hornschuchia; it appears that no one has looked since for the occurrence of polyads within the family (Erdtman, 1945b, 1966). In 1834 von Mohl noted the single aperture in the pollen grains of two undetermined species of Annona from Brazil. Observations covering a few species of Annonaceae were made by other classical workers in pollen morphology, such as Fritzsche and Fischer (cf., Erdtman, 1945b, 1966). Some embryological-cytological studies include information on pollen, the more important being those by Herms (1907), Lecomte (1896), Locke (1936), Periasamy and Swamy (1959), and Samuelsson (1914). Davis (1966) has summarized the embryological data known for the family. In 1952 Erdtman summarized the palynological data then known for the family. This included information on one or two species each for approxi- mately 15 genera (Erdtman, 1966, pp. 49-50). Vander Wyk (1950) included a study of the pollen of the family in his doctoral thesis, which was concerned primarily with vegetative anatomy. Although the section on wood anatomy was subsequently published (Vander Wyk & Canright, 1956), the pollen data were not. Vander Wyk investigated the pollen of 51 genera and 82 species. The study was based mainly on dry pollen from herbarium sheets re-expanded in lactic acid, ANNONACEAE 7 and included no acetylated material. He germinated pollen of Asimina triloba and found that the pollen tube emerged from the proximal surface. Also, he was of the opinion that the aperture in the family was proximal, not distal. It is interesting to note that Agababyan (1967) found pollen germina- tion in Annona glabra, A. cherimola, and A. squamosa to occur on either side of the grain, with usually 75-80 per cent of the grains germinating on the distal side even though that side was thicker. Further studies are certainly needed with living pollen, especially of the more primitive members of the genus, such as Annona muricata. Agababyan’s statement, in the same paper, that the grains of Annona are not catasulcate but rather inaperturate, with the aperture being an artifact of acetolysis breaking the grains, is not borne out by the present comparative study of over 50 species of Annona. The only modern, extensive survey of the pollen of the Annonaceae using acetylated grains is that by Canright (1963). For the purpose of comparison with the results of the present study, a critique of Canright’s paper is given following the pollen descriptions in the present work. MATERIALS AND METHODS The present study includes a survey of 93 genera and approximately 430 species of Annonaceae. Fresh material was collected by the author in Mexico, Central America, Panama, Jamaica, and Colombia. Palynological material was also obtained from herbarium sheets in the following col- lections: Gray Herbarium, Harvard University (cH); Amold Arboretum, Harvard University (4); New York Botanical Garden (Ny); United States National Herbarium, Washington, D.C. (vs); and the Field Museum of Natural History, Chicago, Ilinois (F - During the course of the study some 5,200 permanent slides of pollen samples and cleared stamens were prepared. A set is on deposit in the Paleobotanical Collections of the Botanical Museum of Harvard Univer- sity. Each slide bears either my personal collection number* or my palynological accession number (with a “P” preceding the number). In the case of the latter, the original collector and his collection number are given in the citation of voucher specimens at the end of this study. All material studied and all slides made are vouchered and most of the herbarium specimens upon which this study is based have had their identity verified by the author from the available literature. In the case of the existence of abundant material of particular taxa, a deliberate attempt was made to use herbarium sheets which had been annotated by a specialist in the taxonomy of the family (such as Fries, Diels, et al.) or which were cited in a reliable flora or revisionary study. 8The author’s first herbarium set is deposited in the Gray Herbarium of Harvard University. 8 JAMES W. WALKER Most of the pollen samples were prepared using Erdtman’s (1960) standard acetolysis method with some modification. Rather than boiling the pollen samples, the majority of them were prepared by placing corked centrifuge tubes with pollen and standard acetolysis fluid in an oven over- night at 50-60°C. The material was then washed twice with glacial acetic acid and three times with water. Then the pollen was mounted in glycerine jelly. The use of disposable Pasteur pipettes was found helpful in trans- ferring a mixture of pollen and glycerine jelly evenly to slides, especially when the available material was scanty. In genera with highly reduced exine (all members of the Guatteria group, Sapranthus, and Duguetia), treatment with KOH was found necessary. Again, a corked centrifuge tube containing pollen material and varying concentrations of KOH (up to 1 N) was placed in an oven over- night at 50-60°C. The material was then washed in water 3-4 times, stained in basic fuchsin, toluidine blue, and/or alcian blue, and mounted in glycerine jelly. Tuf-On 74, made by Brooklyn Paint and Varnish Co., was used to seal all pollen mounted in glycerine jelly in order to make the slides permanent. Stamens were cleared in KOH (up to 1 N) in Petri dishes in an oven at 50-60°C. Material was left in the oven until the desired amount of clear- ing was achieved. Then the stamens were dehydrated in an alcohol series, stained in basic fuchsin, cleared in xylene, and mounted in Permount. It was found that the easiest method to dehydrate and clear the stamens was to pipette the fluid out of the Petri dish with a disposable Pasteur pipette, leaving the stamens in the same dish throughout the entire process. The KOH-treatment of pollen grains with reduced exine was found essential for the discovery and demonstration of the disulculate pollen types in the family, while the study of in situ pollen masses in the cleared stamens was necessary for the demonstration of tetrads and polyads in many genera where these structures are easily lost or damaged by acetoly- sis treatment (e.g., polyads breaking up into tetrad-like bodies, etc.). The investigation was carried out with Zeiss Opton brightfield and Wild phase contrast microscopes. Photomicroscopy was through a Zeiss microscope, while Kodak High Contrast Copy Film and Adox KB-14 with Kodak Ektamatic paper and processing were used for the photomicro- graphs. A JSM-2 scanning electron microscope was used to obtain the scanning electronmicrographs. Major PoLLEN CHARACTERS The major features of pollen grains may be conveniently divided into different character-complexes including: (1) pollen-units (and_ their intrastaminal arrangement); (2) polarity; (3) symmetry; (4) apertures; (5) shape; (6) size; (7) exine structure and sculpturing. In the following, an attempt will be made to present the major coricepts and the most important palynological terminology associated with each of the above ANNONACEAE 9 character-complexes, especially as related to the pollen of the Annonaceae. Most terminological usage follows that of Erdtman (1966). Different usage of terms or the introduction of terms other than those of Erdtman will be indicated where appropriate (e.g., the usage of the Faegri and Iversen term “columellae” for Erdtman’s “infratectal bacula”). POLLEN-uNITS.* Most mature pollen grains are solitary (monads) within the thecal chambers of the stamen. However, in a number of angiosperm families the pollen grains at maturity are in dyads, tetrads, polyads (octads, 16’s, etc.), massulae, or pollinia. A pollinium consists of the entire pollen- mass of a thecal chamber. The terms polyad and massulae have been used more or less interchangeably to denote pollen-units larger than tetrads but less than the entire pollen-mass of a thecal chamber. I believe that a useful distinction may be made between the two terms and would suggest using the term polyad for any pollen-unit larger than a tetrad but smaller than a pollinium in which the number of pollen grains is numerically ascer- tainable. I would restrict the term massulae to those pollen masses less than pollinia in which the number of individual grains is not ascertainable, due to very high number and/or a great degree of pollen fusion within the massula. There are approximately 50 families of angiosperms (41 dicot and 12 monocot families) in which all or some members have pollen grains in tetrads or dyads (table 1). Of these, 13 have their pollen grains entirely or almost entirely in tetrads, eight have a significant number of genera with some or all species with tetrads, three have several genera with pollen in tetrads, and the remainder (26 families) have tetrads only very rarely. Dyads characterize two families (Podostemaceae and Scheuchzeriaceae ), while the Cyperaceae have cryptotetrads ( pseudomonads ). While tetrads occur in more than 50 families of angiosperms, polyads are quite rare. From a cursory survey of the literature, it appears that there are only five families in which polyads are known to occur: Annonaceae, Leguminosae (Sorsa, 1969), the genus Hippocratea of the Hippocrate- aceae (Bartlett, 1967), Asclepiadaceae, and Orchidaceae. The latter two families are also the only angiosperm families with massulae and pollinia. Pollen tetrads may be of five different types (cf., Erdtman, 1945b). The most common among the angiosperms as a whole is the tetrahedral tetrad, but among the primitive monosulcate dicots and the monocots, the most common is the tetragonal or square tetrad with the rhomboidal tetrad less common. The decussate or cross tetrad, and especially the linear tetrad, are of rather infrequent occurrence. While the majority of genera of the Annonaceae have solitary pollen grains at maturity (pl. 1:1-2: 8:4; 10:3; 21:2; 45:1,2,5), some 20 genera have their pollen grains in tetrads (table 2). Of these, one (Xylopia) also has a few species with polyads, while another (Annona) has a few with solitary grains, All species of the other 18 genera were found to have 4A pollen-unit is the erolnzay in which pollen is found at maturity within the stamen, i.e., whether in monads (solitary), tetrads, polyads, etc. 10 JAMES W. WALKER tetrads consistently. The most common type of tetrad within the Annona- ceae is the tetragonal tetrad (pl. 23:3; 31:2-3; 32:1,4; 42:5; 46:1). Genera with tetragonal tetrads frequently have some rhomboidal tetrads also. Three genera (Pseudoxandra, Mitrephora, and Pseuduvaria) exhibit mark- edly tetrahedral tetrads (pl. 1:3; 15:4,7). These genera may occasionally have tetragonal (pl. 13:6; 15:5), rhomboidal (pl. 15:3,6), or decussate tetrads also. No examples of linear tetrads were observed in the family. TABLE 1. ANGIOSPERM FAMILIES WITH POLLEN-UNITS OTHER THAN MONADst DICOTYLEDONAE Magnoliidae Epacridaceae** Lactoridaceae*** Empetraceae*** Winteraceae* ** Pyrolaceae*** Annonaceae** (also polyads ) : Monimiac Rosidae N Bila ~ gag erberidaceae RSaCe Papaveraceae Leguminosae** (also polyads ) Podoateiniaasus® * (dyads, possibly Hamamelidae polyads ) Myrothamnaceae*** Onagraceae* Eucommiaceae C Rafflesiaceae Caryophyllidae Hippocrateaceae (polyads) Didiereaceae ( possibly tetrads ) Celastrace Dilleniidae papiadanene arcolaenaceae* ** Asteridae Actinidiaceae Gentianaceae®* Guttifera Apo oe pocynaceae® Tiliaceae Adsepiadaceae (also polyads epenthaceae*** sulae, and pollinia ) Droseraceae*** Solanaceae Begoniaceae Bignoniaceae* Datiscaceae Pedaliaceae Cucurbitaceae Hydrostachyaceae*** Ericaceae*** Goodeniaceae Rubiaceae* MONOCOTYLEDONAE Alismatidae Arecidae ydrocharitaceae Araceae Scheuchzeriaceae*** (dyads) iD Liliidae Commelinidae Philydraceae Juncaceae** idacea ent Vellozia sine Cyperaceae*** (cryptotetrads or Orehidacene** (also polyads, pseudomonads ) assulae, and pollinia) yphaceae*** Bromeliaceae 7Based mostly on data of Erdtman, 1945b, 1966; pe atthe searing to bine has (1968) ; tetrads present unless ier viae indicated; *** all m — whe g majority have pollen in tetrads or dyads; ** a significant number ma Goat eatied ah tetrads or dyads; several genera have pollen i in tetrads or dyads; no mark tA a or dyads are very rare or may only be found in certain individual plants of a species (e.g., pollen tetrads the author found in material from one particular tree of Eucommia). ANNONACEAE 11 TABLE 2. GENERA OF ANNONACEAE WITH TETRADS, POLYADS, AND SEPTATE STAMENS TETRADS POLYADS Xylopia (mostly tetrads), Cymbopetalum (octads), Cardiopetalum (octads), Porcelia ace up to 24’s), Trigynaea (octads), Hornschuchia ( polyads of 16’s), Disepalum octads SEPTATE STAMENS Neostenanthera, Xylopia, Goniothalamus, Richella, Cymbopetalum, Cardiopetalum, Porcelia, Trigynaea, Hornschuchia Six genera were found to have polyads in all species examined (table 2). A seventh (Xylopia) has a few species with polyads (pl. 23:6; 25:1), although the majority of the species in this genus have tetrads (pl. 23:3,5; 24:3; 25:2). Of the six genera constantly with polyads, four have octads (pl. 48:5,6; 50:6; 51:5-6; 52:5), one has polyads of 16 grains, and one has polyads of 16, 18, 20, 24, etc. (pl. 49:3-4). The polyads of some species of Xylopia are distinctive, usually consisting of about 5-6 individually dis- cernible tetrads, while those in the other genera are more or less irregular with no individual tetrads visible. Since the polyads in Porcelia may be in multiples other than four, it would be interesting to investigate micro- sporogenesis and pollen formation in this genus. ine genera of Annonaceae have transversely locellate anthers at maturity (table 2). Five of these have polyads, three have tetrads, and one (Xylopia) has both tetrads and polyads, depending on the species. All genera with polyads were found to have septate stamens at maturity except Disepalum. The tetrads or polyads in the genera with septate stamens are each in a separate compartment within the stamen (pl. 25:1; 30:2; 48:4; 49:5-6). It is of interest to note that the polyads in the sub- family Mimosoideae of the Leguminosae are also separated by septa within the anther locule (cf., Maheshwari, 1950). poariry. The polarity of a pollen grain is of special importance in determining aperture type and hence grain homologies. The determina- tion of grain polarity in genera or species with tetrads at maturity is quite straightforward. In taxa with solitary grains, however, the correct deter- mination of polarity may be somewhat more difficult—one must either rely on comparative studies of related taxa with permanent tetrads or study cytologically the development of the immature pollen tetrad before the grains separate to determine grain polarity with respect to apertures. The polar axis of a pollen grain is that line passing through the center of the grain from the outside to the center of the tetrad (or to the center of the tetrad at the time of its formation in the case of solitary grains). 12 JAMES W. WALKER The equatorial axis perpendicularly bisects the polar axis and forms the boundary between the distal and proximal poles of the grain. The distal pole faces away from the tetrad, while the proximal pole is directed in- ward, facing the center of the tetrad. The two major types of grain polarity are apolar (without discernible poles once the grains are not in tetrads) and polar (with distinct poles). Polar grains may be further subdivided into isopolar (with the equatorial plane dividing the grain into equal halves) and heteropolar (with the polar faces markedly dis- similar). The pollen grains of the Annonaceae may be apolar (the in- aperturates, pl. 7:9), isopolar (the disulculates, pl. 17:7), or heteropolar (the sulcates and ulcerates, pl. 1:4; 61:1-2). SYMMETRY. Symmetry (as well as polarity) is largely determined by apertures. The two major types are radiosymmetry and bilateral sym- metry. Radiosymmetric pollen grains have more than two vertical planes of symmetry (or if only two such planes, then the equatorial axes are equilong ). Bilateral grains have only two vertical planes of symmetry and the equatorial axes are not equilong. In the Annonaceae, all the inaperturates are radiosymmetric, while all the sulcates and ulcerates are bilateral. The disulculates may be either radiosymmetric (pl. 17:6; 18:1) or bilateral (pl. 17:7-8, 10-12; 18:24), depending on whether the equatorial axes are equilong or not. The genus Pseudoxandra is asymmetric-fixiform because of the irregular shape of the grains due to the frequent occurrence of random protuberances of the exine. APERTURES. Apertures are openings or thin areas in the exine through which the pollen tube usually emerges at the time of germination. The evolution of apertures in pollen grains was one of the major advances of the seed plants and the aperture type is one of the most important phylo- genetic characters of pollen grains (cf., table 3). Pteridophytes, in the strict sense, do not have apertures, However, they do have non-homologous, thin areas by which the spores often open. These are the tetrad scars, which may be trilete (triradiate ) or monolete (with one linear scar). It was in gymnospermous plants that the first apertures evolved. Certain fossil gymnosperm pollen (e.g., the pteridosperms ) still has a trilete scar on the proximal face which is homologous to the trilete scar of pterido- phyte spores. The first true apertures, however, evolved at the distal pole and were furrow-like. The palynological term for an elongate, polar aperture is a sulcus and since these first apertures were at the distal (ana-) pole, these grains are known as anasulcate. Most modern gymnosperms are still anasulcate, although some other developments have occurred, such as the formation of air bladders, the secondary loss of the aperture to become maperturate, etc. In the course of the evolution of the flowering plants a new and funda- mentally different type of aperture arose, the colpus. This furrow-like aperture is not polar but equatorial (being perpendicular to the equator ANNONACEAE 949|;OU0W @49| 144 Gee ~ x : (ses0ds) SS LAHdOdIYsld (@9;Dp!od|nspub) CoETIP EI @4D9|nsDuD ; : ea On SWY 3dSONWAS Vv 84D9j;NsDUD 940410911 7 eae | SWY 3dSOISNV (DUD) saeinjsedy apjod)p4siq (Dj}D9) seunjaedy sapjodjpwixolg T ' a @,DO|NSsDUD (\ x‘ @4D4Njsedoul Kitt apaoDuOUUY ey 9} D199|ND4\DO . THE TABLE 3. POLLEN APERTURE EVOLUTION IN THE VASCULAR PLANTS AND FAMILY ANNONACEAE 14 JAMES W. WALKER of the grain). The basic angiosperm pattern has three of these equatorial apertures and the grains are known as tricolpates. However, some of the primitive dicot families such as the Magnoliaceae, Degeneriaceaz, etc. (including the monocots) have retained the primitive anasulcate type of pollen which is so prevalent among the gymnosperms. One of the earliest concepts developed in comparative pollen morphol- ogy, which later became almost a dogma, was that the furrow in sulcate pollen grains was always at the distal pole and hence the grains were always anasulcate. This concept was promulgated by Wodehouse (1935, p. 324) in his classic book on pollen grains. The validity of this hypothesis for annonaceous pollen was first questioned by Bailey and Nast (1943). Since then, the true nature of the annonaceous aperture has been open to some question (Erdtman, 1966; Canright, 1963; Kuprianova, 1967). From a study of the more than 20 annonaceous genera in which tetrads or poly- ads occur, it is quite clear that in all genera except one the aperture is on the proximal (cata-) pole (pl. 23:4; 30:4; 50:6), and not the distal pole as in all other known monosulcate grains, indicating that the family Annona- ceae is unique in having catasulcate pollen. The genus Pseudoxandra is of special interest because some of its species have retained the primitive anasulcate condition characteristic of many of the other “ranalean” dicots. Even more noteworthy is the fact that within the genus the complete transition from anasulcate to catasulcate may be observed. The pollen of Pseudoxandra coriacea has a well-defined distal sulcus (pl. 1:3; 57:1), while the distal sulcus of P. guianensis has some- what weaker margins. Pseudoxandra leiophylla and P. polyphleba are transitional from anasulcate to catasulcate (pl. 2:5), while P. williamsii has a well-defined, proximal aperture (pl. 2:6). Pseudoxandra coriacea is also remarkable in being the only species of the Annonaceae examined to have some trichotomosulcate grains (pl. 1:4; 57:1). Since Pseudoxandra is the only genus to have permanent tetrads among a group of related genera having sulcate pollen (the “Malmea tribe” ), it is difficult to deter- mine with certainty the orientation of the sulcus in these other genera (Malmea, Cremastosperma, Unonopsis, etc.). However, in view of the rare occurrence of catasulcate tetrads in Cremastosperma cauliflorum (cf., Canright, 1963), it is probably best to consider these genera as having catasulcate pollen unless proved otherwise through the cytological study of pollen development. The sulcate pollen grains within the family have a fairly wide range of diversity (cf., pl. 2:1,7-8; 3:1,4-5,7,10-12; 4:1-7; 5:1-46,8; 10:4-6; 19:2; 22:1-3). In a large number of genera the aperture has been lost and the grains have become inaperturate (pl. 8:1-6; 9:3-12; 12:1-12; 13:1-6; 17:1-5; 32:6-9; 44:1-7). In two genera which are characterized mainly by inaperturate pollen (Uvaria and Artabotrys), a few species show the vestigial remains of a reduced sulcus (pl. 9:1; 14:3,4). Another type of aperture in the Annonaceae is found in two different groups and presum- ably arose independently through parallel evolution from inaperturate ANNONACEAE 15 pollen. This disulculate pollen type was previously unknown for the family. A sulculus is a furrow-like aperture found on the equator of the grain and parallel to it. It should not be confused with the colpus, which is also equatorial but perpendicular to the equator. The colpate and derived types of pollen characterize the majority of angiosperms (all the higher dicots), while the sulculate type is restricted to some of the primitive “ranalean” dicots and the monocots. The two groups with disulculate pollen are the genus Sapranthus (pl. 17:6-7; 18:1-4), which is closely related to some genera with inaperturate pollen (Desmopsis, Stenanona, Reedrollinsia), and the closely related genera Guatteria, Guatteriopsis, and Heteropetalum (pl. 17:8-12; 18:5-6). The latter genera form a natural group, the “Guatteria tribe.” Finally, in some genera the catasulcus has been modified (apparently twice in two parallel lines) into a rounded, pore-like aperture. Such a polar aperture is known as an ulcus and since, in the Annonaceae, this rounded aperture is on the inner face, the grains are known as cataulcer- ate (cf., pl. 26:3; 28:1,3,5; 29:1-5; 53:5; 59:3). Thus, with reference to aperture type, the pollen of the Annonaceae may be anasulcate, anatri- chotomosulcate, catasulcate, cataulcerate, inaperturate, or disulculate. (Grains in which the orientation of a polar furrow is unknown may be referred to simply as sulcate. ) sHApE. The shape of a pollen grain is usually correlated with the type of aperture, e.g., tricolpates tend to be globose to elliptic, while monosulcates tend to be boat-shaped. The method and length of pollen preparation may cause the shape of monosulcate grains to vary considerably (cf., pl. 19:2,3). Pollen in the Annonaceae ranges from boat-shaped (pl. 2:8; 3:1; 5:1-3), oblong-elliptic (pl. 17:7-8,10-12; 18:2-6), or triangular (pl. 22:4,6; 94:1-2, 4-5), to disc-like, concave-convex (pl. 23:1; 28:3,5) or rounded (pl. 36:1,5; 38:3; 46:4; 47:1,4) to globose (pl. 7:6,9,10; 8:1-6; 13:1-6; 32:6-9; 44:1-7). sizz. The size of pollen grains is greatly affected by the method of preparation and hence is a most unreliable character. Order of magnitude, based on defined size classes, is probably the single most useful measure- ment of pollen grains. The following size classes, based on the length of the longest grain axis (exclusive of spines in echinate grains), have been adopted, following Erdtman ( 1945a ): Very small grains <10p Small grains 10-25 Medium-sized grains 25-50p Large grains 50-100, Very large grains 100-200. Gigantic grains >200p. The length averages of the grains of different species of annonaceous pollen range from 23-283», while similar average lengths for all species of each genus as a unit range from 24-183, (table 4). Thus, in terms of size classes, pollen in the family ranges from small to gigantic. The 16 JAMES W. WALKER average long axis grain measurement for the family is 60. Genera with average long axes measurements of less than 30y include Cleistochlamys (pl. 32:6-9), Enneastemon (pl. 7:6), Stelechocarpus (pl. 9:11), and Monanthotaxis (pl. 6:5). Genera with grains having an average long axis of more than 100» include Cananga (pl. 26:3), Asimina (pl. 34:3-6), Annona (pl. 33:5), Cardiopetalum (pl. 50:1-2), Fusaea (pl. 26:1; 27:1), Duckeanthus (pl. 26:2), and Cymbopetalum (pl. 47:1-6). Cymbopetalum has by far the largest pollen in the family. The long axis average for the genus is 183, and the averages for the different species range from 130- 283. Some individual grains of Cymbopetalum odoratissimum reach 350p, probably the largest recorded fixiform pollen in the angiosperms (pl. 47:1-3; 59:3; 60:3-5; 61:1-2). EXINE STRUCTURE AND SCULPTURING. The pollen wall (sporoderm) con- sists of two fundamentally different layers: an inner, more or less cellu- losic layer (cf., Faegri and Iversen, 1964) which is destroyed upon acetylation (the intine); and an outer, highly resistant layer, composed of so-called sporopollenins (the exine). Since most modern pollen is prepared for study by acetolysis and the intine is lacking in fossil pollen, for all practical purposes the study of pollen morphology consists of the study of the exine. The exine typically consists of two layers: an inner, basal layer or nexine (nonsculptured exine); and an outer, sculptured layer or sexine (sculp- tured exine). The basic element of the sexine may be thought of as a drumstick-shaped rod (pilum) with a rod-like basal part (baculum of Erdtman, columella of Faegri and Iversen) and a swollen head (caput). If the heads of the pila fuse, a roof-like structure called the tectum is formed and the grain is tectate. If perforations develop in the roof, the grain is tectate-perforate. If the columellae are locally free from the nexine and form folds to make the exine appear wavy, the grains are subsaccate. If the folds are extremely well-developed and run entirely around the grain, the pollen is perisaccate. Grains with free pila not fused by their heads are intectate, while those with the pila laterally fused into a reticu- late pattern but without the formation of a roof are semitectate. A very important concept in the morphology of pollen exine is the differ- ence between structure and sculpturing. In intectate and semitectate grains, the pila comprise both the structure and the sculpturing. How- ever, in tectate grains the possibility exists for other elements to be formed on the roof of the tectum, which are then considered to be the sculpturing. In tectate grains the structure is formed by the columellae (infratectal bacula ), which are enclosed by the tectum. The most important palynological distinction between a photomicro- graph and a scanning electronmicrograph is that the latter shows only the sculpturing (pl. 60:3-5), while the former shows both structure and sculpturing (pl. 61:2) due to the penetration of light waves and the ability of the light microscope to produce optical sections. ANNONACEAE TABLE 4, SIZES IN MICRONS OF ANNONACEOUS POLLEN SMALL GRAINS 10-25 54 Polyceratocarpus, Friesodielsia 24 Cleistochlamys* ( African ) 5 Enneastemon 55 Mitrephora 56 Uvariopsis MEDIUM-SIZED GRAINS 25—50u 57 Uvaria, Phaeanthus 58 Isolona ; 60 Hexalobus plac naa gee 62 Cyathostemma, Uvariastrum 63 Heteropetalum 64 Enantia, Trigynae 65 reer ag fed Monodora 32 Ellipeia, Woodiella, Neouvaria 33 Platymitra, Pseudephedranthus Popowia ( African ) 34 Mezzettia : ‘ 66 Drepan oo | Bseuaey ata, S opawis 67 se leaieats “Pipteatignia: Raimondia 36 Mitrella 69 Unonopsis 70 Anaxagorea, Guatteriopsis 39 Ruizodendron, Oxandra, Sageraea, ran ahem 71 Richella, Pseudoxandra 40 Guam 75 Néoat 41 aa Anomianthus, “- haar enan eg Dasymaschalon, Fissistigma 80 ck — 42 Cleistopholis, Miliusa, ere es te Frid ee 43 Eni 87 Xylopia 44 Pobathi, en G0 Coates, Porctlia 45 Desmos, Orophea 93 Diclinanona 48 Stenanona, Chieniodendron, = usta ts di Sein lent isep wet Af ium 49 Duguetia, Meiogyne, Trivalvaria, 97 Deeringotham Rollinia VERY LARGE GRAINS 100—200u 102 Cananga LARGE GRAINS 50-100 104 Asimina 50 Rolliniopsis, Ephedranthus, 107 Annona Tetrapetalum, Reedrollinsia 108 Cardiopetalum 51 Saccopetalum, Artabotrys 115 Fusaea 52 Sapranthus, Desmopsis 141 Duckeanthus 53 Alphonsea 183 Cymbopetalum * Average long axis measurement of all grains of all species for each genus. The most widely used sculpturing terms are the following: silate (smooth) ornate or rugulate (with e Riveolits ( pitted ) scu vse elements awk fossulate ( groove distribut scabrate (with any fine at A anion wants e (with elongate sculpturin emmate (with sess ents more or less Peele clavate (pilate) sebeagi cexteellaks ( with e soe ve te (warty sculpturing elements parallel to baculate ( with rod-like sculpturing reticuloid ) elements with no swollen heads reticulate (with sculpturing elements as in ‘the clavate forms ) forming a reticular pattern bchidbate (spiny ) The pollen of the Annonaceae is basically tectate with one notable exception, the genus Trigynaea, which is the only definitely intectate member of the family (pl. 44:12; 50:5; 52:1-2; 53: 1-2). Obviously dis- cernible perforations occur in the tectum of over 20 genera (table 5). A 18 JAMES W. WALKER number of genera have their exine and/or columellae so reduced as to make determination of their tectate nature impossible from light micro- scope studies alone. These genera have been described as microtectate (table 5), since in all instances they apparently can be derived from related groups that have a definite tectum. Pollen studies using the trans- mission electron microscope would be very useful here. In a number of these genera, the columellae are probably so reduced that the sexine and nexine may appear simply as two electron-distinct layers. A few subsaccate (pl. 4:7) to perisaccate (pl. 4:1-5) grains were observed in the family (table 5). The columellae may be extremely well-developed (pl. 47:1-3) to moderately well-developed (pl. 3:2) to reduced (pl. 5:7) to indiscernible (pl. 23:3-4). They may be random and solitary (pl. 38:3) to fused lateral- ly into arcs, etc., forming an ornate pattern (pl. 40:1-4), to reticulate (pl. 2:8-12; 37:1-2). The exine may be extremely thick (pl. 27:2; 49:1-2) to extremely reduced (pl. 17:8-12). In some of the cataulcerate forms the exine may be more or less wanting on the entire inner face of the grain (pl. 23:1; 34:6; 47:4-5; 53:5; 59:3; 61:1). The sculpturing runs the gamut from psilate (pl. 7:11) to foveolate (pl. 27:4-6) to fossulate (pl. 57:2) to gemmate (pl. 13:4) to clavate (pl. 44:12; 50:5) to verrucate (pl. 15:7; 58:3-5) to baculate (pl. 53:1-2) to echinate (pl. 7:1-5). Ubisch bodies are very conspicuous in certain genera (pl. 59:1-2,4-5). GENERIC POLLEN DESCRIPTIONS In the following section, formal pollen descriptions are given for some 92 genera of Annonaceae (the description of Saccopetalum is included with that of Miliusa). The format is the same throughout. First, the type of pollen-unit (whether solitary grains, tetrads, or polyads) is given, then the polarity and symmetry. This is followed by the type of aperture, the shape of the grain, then the size class using the size groups outlined above. The range of the long axis averages is taken from the average of the shortest grains and the average of the longest grains for all the species of the genus examined. Usually they are based on five or more grains for each species. The genus average is derived from the averages for all the species of the genus studied. The averages for the tribes, subfamilies, and the family are derived from the averages of the genera in each taxonomic category. Finally, the exine structure and sculpturing is discussed. At the end of each pollen description the number of species examined out of the total number of species in the genus is recorded, including a list of the plates illustrating the pollen of each genus. The particular species examined in each genus may be found by reter- ring to the citation of voucher specimens in the appendix at the end of the work. The genera in this list are arranged in the same order as they are treated in the formal descriptions, with the species arranged alpha- ANNONACEAE 19 TABLE 5. GENERA OF ANNONACEAE WITH PRONOUNCED TECTATE-PERFORATE, MICROTECTATE, AND SUBSACCATE OR PERISACCATE POLLEN EXINE TECTATE-PERFORATE Cremastosperma, Malmea, Ephedranthus, Pseudephedranthus, Pseudoxandra (reduced), Unonopsis, Bocageopsis, Enantia, Uvaria bipindensis, Polyalthia (the 2 sulcate spp.), Monocarpia, Cyathocalyx, Uvariastrum, Uvariopsis, Hexalobus, Monodora (not very MICROTECTATE Tetrameranthus, Monanthotaxis, Enneastemon, Popowia (African), Desmos, Dasy- maschalon, Friesodielsia, Guatteria, Guatteriopsis, Heteropetalum, Anaxagorea, Pipto- stigma, Neostenanthera, Xylopia, Duckeanthus, Fusaea, Meiocarpidium, Cananga, Goniothalamus, Richella SUBSACCATE OR PERISACCATE Subsaccate: Oxandra (slightly in some spp.), Ruizodendron (prominently), Bocageopsis (slightly ) Perisaccate: Onychopetalum ( prominently ) betically under the genus. An alphabetical index to the generic descrip- tions is to be found at the end of this paper, and, when used in conjunction with the listing of plates after each description, serves as an index to the photomicrographs. The genera are arranged according to the proposed subfamilial and tribal groupings. The format of the data given for each genus is repeated at the tribe, subfamily, and family levels so that one may readily acquire an idea of the distinguishing palynological characters of these higher taxonomic categories. ANNONACEAE PoLttEN Morpnotocy: Pollen grains solitary (most of the Malmea sub- family) or in tetragonal, rhomboidal, tetrahedral, or rarely decussate tetrads or in polyads (most of the Fusaea and Annona subfamilies ). Sta- mens sometimes transversely septate, with each tetrad or polyad in a separate compartment (the Cymbopetalum tribe except Disepalum, and in Xylopia, Neostenanthera, Goniothalamus, and Richella of the Fusaea sub- family). Heteropolar, apolar, or isopolar and bilateral or radiosymmetric (rarely asymmetric-fixiform ). Anasulcate (Pseudoxandra spp.), rarely anatrichotomosulcate (Pseudoxandra coriacea), sulcate (the Malmea tribe), catasulcate or cataulcerate (most of the Fusaea and Annona sub- families), inaperturate (most of the Uvaria tribe), or disulculate (the Guatteria tribe and the genus Sapranthus of the Uvaria tribe). Boat- shaped, oblong-elliptic, triangular, disc-like, concave-convex, rounded, or globose. Small to gigantic, long axis measurement averages for the species 23-283, for the genera 24-183, for the family 60. (up to 350» in some grains of Cymbopetalum odoratissimum ). Tectate-perforate to tectate to microtectate, rarely intectate (Trigynaea of the Cymbopetalum tribe), 20 JAMES W. WALKER columellae extremely well-developed (Annona subfamily) to well- developed (Malmea and Uvaria tribes) to reduced to indiscernible (Fusaea subfamily, Guatteria tribe), random and solitary to fused laterally into ares, etc. and ornate to reticulate. Exine surface psilate, foveolate, fossu- late, scabrate, gemmate, clavate, verrucate, baculate, echinate, subsaccate, or perisaccate. Exine extremely thick (Fusaea and Annona subfamilies ) to highly reduced (Guatteria tribe, Sapranthus, and Duguetia), frequent- ly more or less entirely wanting on the inner face (in most members of the Annona subfamily and in many members of the Fusaea subfamily). Number of genera examined: 93 out of ca. 130. Number of species examined: 430 out of ca. 2,300. Pseudoxandra is notable for showing the transition from anasulcate to the catasulcate (or cataulcerate) grains which characterize the great majority of the members of the Fusaea and Annona subfamilies. Most of the pollen of the genera in the latter two subfamilies is in tetrads or polyads, while only three genera (Pseudoxandra, Mitrephora, and Pseudu- varia) of the Malmea subfamily have pollen grains in tetrads. The Malmea tribe is entirely sulcate, the Uvaria tribe is almost entirely inaper- turate (rarely sulcate or disulculate), and the Guatteria tribe is entirely disulculate. The Fusaea subfamily is characterized by cataulcerate grains in tetrads without discernible columellae, while the Annona subfamily has mostly cataulcerate grains in tetrads or polyads with extremely well- developed columellae. Both the Fusaea and Annona subfamilies show pollen gigantism, a high number of genera with tetrads or polyads, and a number of genera with septate stamens with each tetrad or polyad in a separate compartment. The extremely reduced exine of the genera in the Guatteria tribe and the almost total lack of exine on the proximal face of the grains of members of the Cymbopetalum tribe are noteworthy. THE MALMEA SUBFAMILY PoLLEN Morpuotocy: Pollen grains solitary (rarely in tetrahedral tetrads in Pseudoxandra, Mitrephora, and Pseuduvaria). Heteropolar and bilateral (Malmea tribe), apolar and radiosymmetric (most of the Uvaria tribe), or isopolar (the Guatteria tribe). Sulcate (the Malmea tribe and a few species of the Uvaria tribe), inaperturate (most of the Uvaria tribe), or disulculate (the Guatteria tribe and Sapranthus). Boat-shaped to globose to oblong-elliptic. Medium-sized to large (rarely small), long axis meas- urement averages for the genera 25-81, average for the subfamily 59p. Tectate-perforate to tectate to microtectate, columellae distinct to reduced to indiscernible, random to reticulate, exine surface psilate, gemmate, verrucate, baculate, or echinate, infrequently subcaccate to perisaccate, exine sometimes highly reduced (the Guatteria tribe, Sapranthus, and Duguetia). Pseudoxandra is the only genus in the family with some species that are ANNONACEAE 21 definitely anasulcate, rather than catasulcate or cataulcerate, as is the case with all other genera in the family in which the position of the polar aperture is known. Pseudoxandra, Mitrephora, and Pseuduvaria are the only genera in this subfamily with tetrads. Desmos, Dasymaschalon, and Friesodielsia are very distinctive with their strongly echinate sculpturing. The Malmea tribe is entirely sulcate, while the great majority of the genera of the Uvaria tribe have inaperturate grains. The Guatteria tribe are all disulculate, with Sapranthus (in the Uvaria tribe) being the only other disulculate genus in the family. The Guatteria tribe is remarkable for its extremely reduced exine. THE MALMEA TRIBE PotteN Morruotocy: Pollen grains solitary, rarely in tetrads (Pseudo- xandra). Heteropolar, bilateral (rarely asymmetric-fixiform in Pseudo- xandra). Sulcate, rarely trichotomosulcate (Pseudoxandra coriacea). Boat- shaped. Medium-sized to large, long axis measurement averages for the genera 39-8lp, average for the tribe 59,. Tectate-perforate to tectate, columellae distinct, well-developed to reduced, random to reticuloid to reticulate. Grains occasionally more or less subsaccate to perisaccate (Oxandra, Ruizodendron, Bocageopsis, Onychopetalum). Pseudoxandra is very important palynologically because of the transi- tion within the genus from anasulcate to catasulcate pollen. Pseudoxandra R. E. Fries N MoRPHOLOGY: Pollen grains in tetrahedral tetrads 5 pineapuen da ee or protuberances. Anasulcate with the sulcus frequently curved (P. coriacea, P. guianensis) to Geshe tical cuthes Icate ( . leiophylla, P. polyphleba) to catasulcate (P. williamsii), ently anatrichotomosulcate (P. oo slightly subsaccate near the aperture the found in — a. i oblong, elliptic, rounded or triangular AMB.5 Large grain longe — 71. Tectate, caaoellas random to loo: sely ornate retiuloi, > ia but omewhat reduced. Sculpturing (in P. c afew fossulate, tectate-perfo Number of species examined: 5 out of 6. Plates: 1:3-5; 2:5-6 57:1-2 Cremastosperma R. E. Frie POLLEN MORPHOLOGY: Pollen “ee solitary. Heteropolar, bilateral. Sulcate. Boat- shaped with elliptic to ice AMB. Large grains, longest axis 63-95, a er 80x. Tectate- gira columellae random, reticuloid, or reticle, distinct an - developed (very prominent and highly characteristic in C. a malum Number of mei examined: 9 out of 17. Plates: 3:1-6. Malmea R. E. Frie POLLEN MORPHOLOGY: n grains $ sue Fete por, bilateral. Sulcate. Boat- shaped with rounded, deg or elliptic AMB. Large grains, longest axis 67—-93u, av- erage 8lu. Tectate-perforate, c columellae random to highly reticulate, distinct and well- cevelapet: Sculpturing (in M. costaricensis) psilate with medium-sized tectal perfora- See of species examined: 8 out of 14. Plates: 1:1; 2:1-4, 7-12; 57:3-4. 5AMB is the outline of a pollen grain one sees nage ns — axis is directed towards the observer; it may or may not coincide with the equator of the g¢ 22 JAMES W. WALKER apa S. Moore POLLEN MORPHOLOGY: Pollen grains solitary. Heteropolar, bilateral. Sulcate. Boat- shaped. a staat to large, ae axis 43-58u, average 50u. Tectate-perforate, columellae random to reticuloid to Picea head and well-developed. Number of species examined: 2 out of 4. Plate Pseudephedranthus Aristeguieta POLLEN MORPHOLOGY: Pollen grains solitary. Heteropolar, bilateral. Sulcate. Boat- shaped. Medium-sized, rar ‘deere axis 33u. Tectate-perforate, columellae reticu- late, distinct and well- developed. Number of species abhi yy 4 -out of. 1: Plates: .3:7. Oxandra A. Rich. POLLEN MORPHOLOGY: Pollen grains solitary. Heteropolar, bilateral. Sulcate. Boat- shaped. Medium-sized, longest axis 31-48u, average 39u. Tectate, cseapre ae random to reticuloid, distinct, somewhat reduced, slightly subsaccate in some grain: Number of species examined: 10 out of 25. Plates: 3:10-12 Ruizodendron R. E. Frie POLLEN MORPHOLOGY: Pollen grains s vont Heteropse, sok Sulcate. — Number of species pmeras 1 out of 1. Pla nonopsis R. E. Frie LEN MORPHOLOGY: Pollen oo pms Bow opolar, bilateral. Sulcate. Boat- ip, arge, longest axis 50-87u, average 69u. Tectate-perforate, columellae distinct, well leveled. random to highly reticulate. umber of species examined: 12 out of 33. Plates: 1:2; 5:1-2. Bocageopsis R. E. Fries POLLEN MORPHOLOGY: Pollen grains solitary. Heteropolar, bila teral. Sulcate. Boat- sha 9 -sized, average longest axis 44u. Tectate-perforate, columellae distinct, well-developed, random, slightly atentenie e. Number of species exami inca 1 out of 3. Plates: 4:6. Onychopetalum R. E. Fries POLLEN MORPHOLOGY: Pollen grains ory, Heteropolar, bilateral. Sulcate, the sulcus long and narrow. Boat-shaped. Medium-sized, longest axis 40-42u, average 41 Tectate, een are distinct but sites reduced, prominently perisaccate with distinctive loose fo Number of species aWe 2 out of 4. Plates: 4:1-5. Enantia Oliv. POLLEN MORPHOLOGY: n grains solitary. Heteropolar, bilateral. Sulcate. Boat- sha: €, average est axis 64 ad er erforate, columellae distinct and cond meta. a . . P Number of species examined: 1 out of 10. Plates: 5:4—5. THE UVARIA TRIBE Potten Morrnotocy: Pollen grains solitary, rarely in tetrads (Mitrephora, _ Pseuduvaria). Apolar (rarely heteropolar or isopolar), radiosymmetric (rarely bilateral). Inaperturate, rarely sulcate (Desmos, Friesodielsia, Polyceratocarpus, Uvaria spp-, Polyalthia spp., Artabotrys spp., Mono- carpia) or disulculate (Sapranthus). Globose to rarely boat-shaped or oblong-elliptic. Medium-sized or large (rarely small), long axis measure- ment averages for the genera 25-77, average for the tribe 45y. Tectate or ANNONACEAE 93 tectate-perforate, columellae distinct (rarely indistinct), well-developed to reduced, random to reticulate, exine surface various—often verrucate, less frequently gemmate, baculate, or strongly echinate (Desmos, Dasym- aschalon, and Friesodielsia). Exine much reduced in Sapranthus and Duguetia, less so in Uvaria, Anomianthus, Tetrapetalum, and Cyatho- stemma., Mitrephora and Pseuduvaria are distinctive with their predominantly tetrahedral tetrads. Desmos, Dasymaschalon, and Friesodielsia are set apart by their very prominent echinate sculpturing. Although the pollen of Sapranthus is disulculate, the genus is closely related to Stenanona, Reedrollinsia, and Desmopsis and belongs in the Uvaria tribe on the basis of the totality of its characters. Deemipt nae echinate Carpesdectal P) with spines up to 4u long and Scena minute columellae-like pattern in some ae. others with more or less Graranare crystalline exine. Three of ni nine species examined were not echinate and differed from the other species in a mber of characters and hence may be misplaced in the genus. They are D. insularis, D. leucanthus, and D gynus. +t of species examined: 9 out of ca. 25. Plates: 5:8—11; 6:4. Dasymaschalon (Hk.f. & Th.) Dalla Torre & Harms POLLEN MORPHOLOGY: Pollen grains soli Apolar, radiosymmetric. Inaperturate (if any sulci occur they are difficult to distinguish ae a - =n hie ea G — id oblong. Mostly medium-siz e larger th nges d, lon 32-54u, average 41y. Microtectate, echinate (supratectal 3), eh seal: developed spines which are micromucronate. Exine with minute columellae-like pattern which is definitely scabrate sculpturing an and not infratectal columellae in D. sootepense. The pollen of D. clusiflorum is distinctive in not being ecard me ona & verrucate. Number of species examined: 5 out of ca. 12. Plates: 1:6; §:12 ; 7:1-3; 1-2. Friesodielsia van Steenis ( cigs ie Bl. ex Hk-f. & Th.)® LLEN oLocy: Pollen grains — eteropolar or apolar, bilateral or radio- at Sa (P) or — so sulcate condition being difficult to dating uish from chance folds in the rather thin om) possibly catasulcate in F. bakeri te) oblong to oval. Medium- -sized, longest axis 35—48u, average 42u. Microtectate, echinate (supratectl) with spines well-developed hat — ced in F. glauca). Exine with minute columellae- rican Arica are not pene with the Asian genus Friesodielsia, cf.. Slee tea ( Afri Number of species oo 4 out of ca. 40, Plates: 7:4-5. Monanthotaxis Baill. POLLEN MORPHOLOGY: Pollen grains solitary. Apolar, radiosymmetric. Inaperturate. Globose. Medium-sized, average longest axis a Microtectate, microbaculate (supra- tectal ?). Exine with no distinct columellae patte umber of species examined: 1 out of 4. Plates: 6: “ae of a genus : hepatics. Both Fries (1959) and Hutchinson (1964) th bu SOxymitra is a later (cf, fn. 15, p56), t this can no homonym 0 same hy Ox — itra congeneric with the genus Pilate longer be supported, as pollen morphology a shows that the two genera belon pctceittion In apes van Steenis proposed a new name, Friesodielsia, for the genus g in separate 24 JAMES W. WALKER Enneastemon Exell OLLEN ature pea Pollen erains solitary. Apolar, spend agg fag Inaperturate Clobos ose. Sma medium-sized, longest axis 23-264, average 25y. Microtectate, sc niee aeeed Pissarane ). "Pacing with no eau edsalian pattern Number of species examined: 3 out of ca. 10. Plates: 6:6; Popowia Endl. (African) LEN MorPHOLOGY: Pollen grains solitary. Apolar, radiosymmetric. Inaperturate. Globo ose. Medium-sized, longest axis 29-36u, average 33u. Tectate to microtectate, coarsely verrucate to microbaculate. Exine with distinct columellae or transparent and rebie oe ne without discernible columellae. species from Africa and oe inte’ which have been described under the gems Popowia are not congeneric with Asian Severe cf., Verdcourt, 1969. mber of species examined: 3 out of ca. 65. sa 15:8-1 Desmopsis Safford ee seca well-developed, random, surface pattern low verruca verrucate areas appearing as dark, often ease “pacdiies at level when columellae are Number of species examined: 11 out of ca. 16. Plates: 7:10; 8:4—5. Stenanona Standl. POLLEN MORPHOLOGY: Pollen eas solitary. Apolar, radiosymmetric. Inapertur Globose. Medium-sized, longest ax 50u, average 48. Tectate, columellae eae oe distinct and well-developed, exine ee e pattern loosely verrucate. Number of species examined: 2 out of 2. Plates: 7:7-8 eedrollinsia Walker, gen. nov FLORAL MORPHOLOGY nat cauliflorous, nape articulate, with a bract both above and below the etic . Sepals 4-5, in one whorl and basally fused, petals variable in number, mostly in two ors as Sock: ig and i a valvate, maroon at maturity. Stamens peltate. Ovules several (ca. 4 DISTRIBUTION: The single species is found in the state e Chia ati Mexis POLLEN MORPHOLOGY: Pollen grains solitary. Apolar, osymmetric. rturate. Globose. Medium-sized, average longest axis 50u. acti: cchriastlen at distinct and well-developed, exin Shes ern low verrucate with verrucate areas appear- Sculpturing more or less psilate with some pits and the exine surface compressed into —_ of weakly upraised areas (these appearing as ves: ar nase tches in LO-analysis).§ Number of species examined: 1 out of 1. Plates 7:9; 8:1-3; Sapranthus Seem. EN MORPHOLOGY: Pollen grains soli Isopolar, radiosymmetric or bilateral. Disulculate. Globose or oblong. Medium-sized to arge, longest axis 32-62, average 5: measurements from unacetylated, KOH-treated grains). Tectate, tee faint but discernible, random to reticulate. Exine thin ot quite reduced, intine thick. Number of species examined: 9 out of ca. 12. Plates: 17:6-7; 18:1-4. Tetrameranthus R. E. Fries POLLEN MORPHOLOGY: Pollen grains solitary. Apolar, radiosymmetric. Inaperturate. 7Flores arenes pedunculus articulatus, cum bractea et supra et infra articulum. Sepala.4—5, in uno verticillo et basaliter connata, petala quoad numerum variabilia, pro parte maxima in verticillis duobus cum Pict etalis uterque, longa et ligulata, valvata, ad maturitatem marronina. Stamina ee Pollen a. Ovula aliquot (ca. 4), lateralia. Walker 357-GH ebay NY, US es). a new genus of Annonaceae is named after my mentor and friend, Dr. Reed C. Rollins, Asa Gray Professor of Siacaate Botany and Director = the Gray Herbarium of Harvard University. sce. leben (1966) for a discussion of LO-an ANNONACEAE 95 Globose. Medium-sized, Neiiieas longest axis 44u. Microtectate, columellae not discern- ible, exine surface psilat Number of species pitta 1 out of 2. Plates: 7:11. Duguetia St. Hil. POLLEN MORPHOLOGY: Pollen grains solitary. Apolar, Depilg’ Sap aoa Inaperturate. Globose. Medium-sized or large, longest axis 30-80u, average measurements from unacetylated, KOH-treated grains ). Tectate, pa ast te dacernihie but highly reduced, exine thin and quite ont eb Number of species examined: 10 out of 74, Plates 7:12. a ia Engl. & Diels POLLEN MORPHOLOGY: Pollen gralee es itary. Sep Aaa bilateral. Sulcate, with a fragile sulcus with ragged margins. Boat-shaped. Large, average longest axis 54u. hie Siac distinct but somew aa reduced. r of species examined: 1 out of 7-8. Plates: 5:6-7. Uvaria L. POLLEN MORPHOLOGY: Pollen grains solitary. Apolar, radiosymmetric (rarely hetero- polar and bilateral). Inaperturate (rarely sulcate, with the sulcus reduced in length, in U. bipindensis ). Globose. Medium-sized to large, longest axis 40-824, average 57x. Tectate, columellae ‘ons to caer e, reduced, exine generally thin and reduced, usually with characteristic wr appear arance. (Col ets rather well- developed i in U. bipindensis and distinctly tectate-perforate ) Number of species examined: 16 out of ca. 175. Anomianthus Zoll. POLLEN MORPHOLOGY: Pollen grains solit tary. Apolar, radiosymmetric. Inaperturate. Globose. Medium-sized, average longest axis 41u. Tectate, columeliae discernible, reduced, random, exine somewhat reduced. Number of species examined: 1 out of 1. Plates: 9:3. Tetrapetalum Miq. POLLEN MORPHOLOGY: Pollen grains solitary. Apolar, radiosymmetric. Inapertura Globose. iat deel average se ey axis 50u. Pactele. columellae ditick aca Ha exine somewhat reduced, with appearance. Number of species paste be 1 out of 2, Plates: 9:4. ia Hk.f. & Th. oRPHOLOGY: Pollen grains soli geen radiosymmetric. Inaperturate. es ay Nagra average longest axis 32p. Tectate, columellae distinct, random, ati with somewhat of a raked appear ance. Yumber of species examined: 1 out of ca. 5. Plates: 9:5. Cyathostemm POLLEN MORPHOLOGY: Pollen grains solitary. py radiosymmetric. Inapertu Globose. Medium-sized or large, longest axis 44—82u, ee _ Tectate, ao ei distinct but reduced, exine reduced, with wrinkled appearan Number of species examined: 3 out of 8. Plates: 9:6. Enicosanthum Becc. LLEN MORPHOLOGY: Pollen grains solitary. Apolar, radiosymmetric. In ee . Medium-sized, longest axis wu, average 43u. Tectate, columellae very well-developed, random to ‘ously reticuloid. Exine surface weakly verrucate, the verru: as more or less irre and appearing as darker areas at lower focus. Number of species examined: 3 out of ca. 16. Plates: 9:7-8. Cleistopholis Pierre ex Engl. oRPHOLOGY: Pollen grains solitary. Apolar, radiosymmetric. Inaperturate. Clobose re oblong. Medium-sized, longest axis ia average 42u. Tectate, columel- lae distinct but not very wong developed, as Number of species examined: 2 out of 3-4. Plates: 9:9. 26 JAMES W. WALKER Friesodielsia van Steenis (African) POLLEN MORPHOLOGY: Pollen grains et. Apolar, radiosymmetric. Inaperturate. Globose. Large, longest axis 52-56y, av e 54u. Tectate and coarsely verrucate. It is evident that the African species ecsibed under this genus are not congeneric with the Asian Friesodielsia Number of species PRES 2 out of ca. 15. Sageraea Dalzell POLLEN MORPHOLOGY: Pollen grains solitary. Apolar, radiosymmetric. Inaperturate. Globose. Medium-sized, longest axis 38-40u, average 39. Tectate, columellae very well-developed, random. Exine surface weakly verrucate, the verrucate areas appear- ing as darker spots at lower focus Number of species examined: 3 out Pe ca. 9. Plates: 9:10; 10:1. Stelechocarpus ( BI.) Hk.f. & Th. LLEN MORPHOLOGY: Pollen grains solitary. Apolar, radiosymmetric. Inaperturate. Globose. Medium-sized, average longest axis ae Pidite, columellae distinct, reduced. Exine surface very weakly verrucate, the verrucate areas more or less elongate. Number of species examined: 1 out of 5. Plates: 9:11. Alphonsea Hk.f. & Th. POLLEN MORPHOLOGY: Pollen grains solitary. Apolar, radiosymmetric. Inaperturate. Globose. Medium-sized to large, longest axis 44-82u, average 53. Tectate, columellae istinct, more or less well-developed. Exine surface weakly verrucate to rather well- developed verrucate. Number of species examined: 10 out of ca. 30. Plates: 9:12; 11:1. Rauwenhoffia Scheff. POLLEN MORPHOLOGY: Pollen grains solitary. Apolar, radiosymmetric. Inapertur — Las. —— axis 66-94, average 77u. Tectate, columellae distinct. ee surface ely verrucate. ro we species Sas: 3 out of 5. Plates: 10:2; 11:2. Polyalthia BI. LLEN MORPHOLOGY: Pollen olit lar, radiosymmetric (rarely hetero- polar and a Ingpertate (ulate fn fe ni and P. hypoleuca). Globose (rarely boat-sha to large, longest axis 30-74u, average 44u. Tectate, columellae generally ae pera well-de veloped, exine surface verrucate with verrucate areas often appearin distinct, more or less irregular, dark patches at lower focus. é pakians: ses i mw columellae very Pollen and floral morphology re equire the removal of P. petelotii and P. plagioneura from — and their transference to the genus Disepalum (cf., pollen description for Disepalum Number of species examined: 22 out of ca. 150. Plates: 10:3-6; 11:3-8; 13:1; 57:5-6. Meiogyne Miq. POLLEN MORPHOLOGY: Pollen grains solitary. radiosymmetric. Inaperturat Globose. Modimaared to large, longest axis J gg , average 49u. Tectate, Bac aio 6 distinct to faint, m r les: Number of species piteatee 3 out of ca. 8. Chieniodendron Tsiang & P.T. Li POLLEN MORPHOLOGY: Pollen grains s olitary. Apolar, radiosymmetric. Inaperturate cncunpte Medi li a average longest axis 48u. Tectate, columellae distinct, more or Number of species examined: 1 out of 1. Plates: 11:9. Mezzettia Becc. POLLEN MORPHOLOGY: Pollen grains solitary. Apolar, radiosymmetric. Inaperturate. ANNONACEAE oT rio Medium-sized, longest axis 30-36u, average 34u. Tectate, columellae distinct, ania of species examined: 4 out of 7. Plates: 11:10. Woodiella Merr. POLLEN MORPHOLOGY: Pollen grains solitary. Apo olar, radiosymmetric. Inaperturat Globose. Medium-sized, average longest axis 32u. Tectate, columellae distinct, exine sew coarsely verrucate. mber of species examined: 1 out of 1. Plates: 11:11—-12. Neouvaria Airy-Shaw POLLEN MORPHOLOGY: Pollen grains solitary. Apolar, r radiosymmetric. Inaperturate. Globose. Medium- i average longest axis 324. Tectate, columellae indistinct, exine surface microbaculat Number of species he 1 out of 2. Plates: 12:1-2. Papualthia Diels POLLEN MorPHOLOGY: Pollen grains solitary. mage eae Sagas Inaperturate lobose. aang to large, longest axis 34-60u, average e 48u. Tectate, columellae well-developed to faint, random, exine surface spine eit verrucate with the verrucate areas prominen r, more or less rounded cing at a focus. Number of species examined: 5 out of ca. 20. Plates: 12:3; Miliusa Leschen. ex A. DC. (including Saccopetalum Benn. ) LEN MORPHOLOGY: Pollen grains gh Apolar, radiosymmetric, Inaperturat Globos ose. Modiimcebibd or large, longest 36-58u, average 42u ( Wiliuse) or Sl ( Saccopetalum). Tectate, columellae generally Nhe nai 3 exine surface some- times verrucate with the verrucate areas prominent as darker, more or less rounded patches at lower focus, scxtustsings Dearest gemmate f oe elds ulata). Number of species examined: 9 out of ca. 40. Plates: 12:4—7; 13:3-4; 12 Fissistigma Griff. POLLEN MORPHOLOGY: Pollen grains solitary. Apolar, radiosymmetric. Inaperturate. Globose. Medium-sized to large, longest axis 30-56u, average 41x. is columellae distinct, random. Number of species examined: 7 out of ca. 80. Plates: 12:9. Mitrella Miq. POLLEN MORPHOLOGY: Pollen grains solitary. Apolar, radiosymmetric. Inapertur: Globose. Medium-sized, average ace axis iat Tectate, columellae distinct, tn Number of species examined: 1 out of 5. Plates: 12:1 Melodorum Lour. oRPHOLOGY: Pollen grains solitary. Apolar, radiosymmetric. Inaperturate. Globose ge, longest axis 64-70u, average 67u. Tectate, columellae distinct, some- what well- ey he random. Number of species examined: 2 out of ca. 3. Plates: #2711. Oncodostigma Diels POLLEN MORPHOLOGY: Pollen grains solitary. Apolar, radiosymmetric. Inaperturate Globose. M Medivcs-aodd, longest axis 36-42, average 39u. Tectate, ii distinct, random Number of species examined: 2 out of 3. Plates: 12°42; Guamia Merr POLLEN MORPHOLOGY: Pollen grains solitary. Apolar, radiosymmetric. Inaperturate Globose. Medium-sized, eheeat longest axis 40x. te, columellae oe random. Number of species examined: 1 out of 1. Plates: 14:1-2. Artabotrys R. Br. POLLEN MoRPHOLOGY: Pollen grains solitary. Apolar, radiosymmetric, sometimes 28 JAMES W. WALKER heteropolar and planet Inaperturate or sulcate with a reduced sulcus (A. suaveolens, A. trichopetalus). Globose. Medium-sized to large, longest axis 38-60u, average 5lu. Tectate, ne clistint sometimes aes developed, random, exine surface some- times weakly ve Number of species ene 6 out of ca. 100. Plates: 13:5; 14:3-8. Monocarpia Miq. POLLEN MORPHOLOGY: Pollen grains solitary. Heteropolar, bilateral. Sulcate. Boat- sh ge, av a longest axis 8lu. T see aaboda columellae distinct and well-developed, reti Number of species examined: 1 out of 1. Plates: 5:3. Cyathocalyx Champ. ex Hk.f. & Th. POLLEN MORPHOLOGY: Pollen grains solitary. Apolar, radiosymmetric. ee Globose to oblong-elli os Large to medium-sized, longest axis 43-80u, average 65x. Tectate-perforate, columellae distinct, random to reticuloid. Lecaikocaiae. piesa differs somewhat and may be sulcoidate. Number of species examined: 7 out of ca. 15. Plates: 14:9-10. Drepananthus Maing. ex Hk.f. POLLEN MORPHOLOGY: Pollen grains solitary. Apolar, radiosymmetric, Inapertu polar. Globose. —— to medium-sized, longest axis 47—75u, average 66u. Tectate, ie distinct, random Number of species examined: 5 out of ca. 10. Plates: 14:11. Daca Bl. feat * species examined: 9 out of ca. 60. Plates: 14:12; 15:1,7; 16:5; 58:3-5. A atymitra Boerl. POLLEN MORPHOLOG n grains solitary. Apolar, radiosymmetric. Inaperturate. Globose. Mediuin sized. overage longest axis - Tectate, columellae distinct, random. Number of species examined: of 2. Plates: 15:2. Mitrephora Hk.f. & Th. POLLEN MORPHOLOGY: Pollen grains in tetrahedral tetrads, longest tetrad axis 70—90u. Apolar, radiosymmetric. Inaperturate. Globose. Medium-sized to large, longest axis m, average 55u. Tectate, columellae distinct, random, exine surface sometimes rather well-developed verrucate. Number of species examined: 7 out of ca. 40. Plates: 13:6; 16:1. Fseuduvaria Miq small perforations appearing in the tectum at very high magnification. Number of species examined: 4 out of ca. 35. Plates: 15:3-6; 16:2-4 (see also 15:7; 16:5; 58:3-5). Popowia Endl. MORPHOLOGY: Pollen grains solitary. Apolar, radiosymmetric. Inaperturate Chibeus Medium-sized, longest axis — average 35 u. Tectate, columellae distinct, random, exine surface weakly verruca ANNONACEAE 29 The African species are not congeneric with the totally Asian genus Popowia, cf., Popowia ( African). Number of species examined: 4 out of ca. 40.9 Plates 17:1-2. Phaeanthus Hk.f. & Th. POLLEN MORPHOLOGY: Pollen grains solitary. Apolar, radiosymmetric. Inaperturate. Globose. Medium-sized or large, longest axis 46-67, average 57u. Tectate, columellae distinct or faint, random, exine surface more or less smooth, reduced or somewhat weakly verrucate. Number of species examined: 2 out of ca. 20. Plates: 16:6; 17:3-4. Trivalvaria Miq. OLLEN MORPHOLOGY: Pollen grains solitary. Apo olar, radiosymmetric. Inapertura Cibo, Medium-sized, longest axis 48-50u, average 49u. Tectate, columellae ee random. Number of species examined: 2 out of ca. 6. Plates: 17:5. THE GUATTERIA TRIBE PottEN Morpuotocy: Pollen grains solitary. Isopolar, bilateral or radio- symmetric. Disulculate. Elliptic to oblong to rounded. Large, long axis measurement averages for the genera 63-90y, average for the tribe 74 (measurements from unacetylated, KOH-treated grains). Microtectate, exine highly reduced, no columellae discernible or possible columellae faint, intine thick. The members of this tribe have very similar pollen which is distinctive for the family in being disulculate. The only genus outside of this tribe with disulculate pollen is Sapranthus, which belongs in the Uvaria tribe on the basis of all its characters. The pollen of the Guatteria tribe is also notable for its highly reduced exine, which is quite remarkable for a non-aquatic group. Guatteria og & Pav POLLEN MORPHOLOGY: Pollen grains solita Siceclek —— (and eget ge longest axis 90% (measurements from unacetylated, KOH treated grains an My limited et hd Misdobactate, exine highly reduced, faint columellae (?) visible, grains of G. sities (su et nus An Number of species examined: 1 out of ca. se 10 Plates: 17:8; 18: Guatteriopsis R. E. Fries MoRPHOLOGY: Pollen grains solitary. Isopolar, radiosymmetric. Disulculate laitae: Large, average hee axis 70u (measurements from unacetylated, KOH- treated grains). Microtectate, exine highly reduced, no columellae discernible, intine thi Wamber of species examined: 1 out of 4. Plates: 17:9. Heteropetalum Benth. POLLEN MORPHOLOGY: Pollen grains solitary. Isopolar, bilateral. Disulculate. Elliptical- ®A duplicate sheet of a type collection cited by Diels as Popowta pgs —_ in the oo of the Arnold Arboretum has tricolpate pollen and is set material of th y Annonac 19Permanent slides were prepared for only one speci of sees genus, sees is haa difficult to prepare; however, non-permanent slides were : oe of about a dozen species, including both subgenera. 30 JAMES W. WALKER oblong. Large, average of longest axis 63u (measurements from unacetylated, KOH- treated grains). Microtectate, exine highly reduced, no columellae discernible, intine thick Number of species examined: 1 out of 2. Plates: 17:10—-12. *% THE FUSAEA SUBFAMILY PotteEN Morpuotocy: Pollen grains solitary (Anaxagorea, Piptostigma), in tetragonal tetrads or polyads of ca. 5-6 usually individually discernible tetrads (Xylopia), or in very loose tetragonal to tetrahedral tetrads. Stamens septate with each tetrad or polyad in a separate compartment in Xylopia, Neostenanthera, Goniothalamus, and Richella. Heteropolar, bilateral. Sulcate (Anaxagorea, Piptostigma) or catasulcate to cataulcerate. Boat- shaped, more or less globose, triangular, or disc-like, concave-convex. Large to very large, long axis measurement averages for the genera 67- 141p, average for the subfamily 92. Microtectate, columellae (?) faint, mostly not discernible, exine surface more or less psilate, often with conspicuous pitting. The Fusaea subfamily is notable because the pollen grains of all its members (except Anaxagorea and Piptostigma) are in tetrads or polyads (Xylopia spp.). The occurrence of septate stamens in Xylopia, Neoste- nanthera, Goniothalamus, and Richella is also noteworthy. Pollen gigan- tism is present in a number of species in this subfamily, which is charac- terized by the extreme reduction of the columellae so that they are indiscernible, and by the very thick and more or less psilate exine. Anaxagorea St. Hil. POLLEN MORPHOLOGY: Pollen grains solitary. Heteropolar, bilateral. Sulcate. Boat- shaped to more or less globose. Large, longest axis 56-954, average 70u. Microtectate, columellae aint to more or less indiscernible, exine somewhat reduced, exine surface more or less psilate. Number of species examined: 11 out of 29. Plates: 19:1-8; 20:1—2; 21:1-2. Piptostigma Oliv. POLLEN MORPHOLOGY: Pollen grains solitary. Heteropolar, bilateral. Sulcate. Boat- shaped. Large, longest axis 57-76, average 67u. Microtectate, columellae (?) faint but discernible, exine somewhat reduced, exine surface more or less psilate. Number of species examined: 3 out of 15. Plates: 22:1-3. Xylopia L. POLLEN MORPHOLOGY: Pollen grains in tetragonal tetrads or polyads of ca. 5-6 usually individually discernible tetrads (X. brasiliensis, X. ferruginea, X. micans, X. africana). Stamens septate with each tetrad or polyad in a separate compartment. o Fusaea ( Baill.) Saff. POLLEN MORPHOLOGY: Pollen grains in very loose tetragonal to tetrahedral tetrads. , bi . Cataulcerate. Disc-like, concave-convex. Very large, longest axis 103-126u, average 115y. Microtectate, no columellae discernible, exine very ANNONACEAE 31 thick, exine surface with pitting, otherwise psilate. Sculpturing (in F. longifolia) psilate, with infrequent pits, er bodies very nv aae ous. Number of species examined: 2 out of 3. Plates: 22:9; 26:1; 27:1; 59:4—-5. Duckeanthus R. E. Frie NN MorPHOLOGY: Pollen grains in very loose Ae ragonal to tetrahedral tetrads. Heteropolar, bilateral. Sino Disc-like, concave-convex. Very large, average longest axis 141u. a no columellae mere ernible, exine very thick, psilate. Number of species examined: 1 0 f 1. Plates::26:2; rn Hk.f. & Th. LLEN MORPHOLOGY: Pollen gra ery loose tetragonal to tetrahedral tetrads. psa olar, bilateral. Pawar iaiey Boat- shaped-oblong to rounded. Large to ve large, longest axis mu, average 102u. Microtectate, iigemedon (?) present, pitting very eee especi Hly in C. latifolia. Aperture margin conspicuously subsaccate in C. a, giving a very wrinkled ap arance are the proximal face of the grains. rte ew (in C. odorata) psilate, with some pits, Ubisch bodies con- spicuous. Number of species examined: 2 out of 2. Plates: 22:10; 26:3-6; 27:3-6; 59:1-2. Meiocarpidium Engl. & Diels LLEN MORPHOLOGY: Pollen gr. aay in very loose tetragonal to tetrahedral tetrads. Heteropolar, bilateral. Cataulcerate. Disc-like, concave-convex. Large, average longest axis 96u. Microtectate, no colu mellae discernible, exine thick, exine surface pitted, otherwise more or less psi Number of species ith aa 1 out of 1. Plates: 28:1. Neostenanthera Exell POLLEN MORPHOLOGY: Pollen grains in very loose tetragonal to tetrahedral tetrads. Stamens septate, with each tetrad probably in a rae compartment. Heteropolar bilateral. Catutileerate. Disc-like, concave-convex. Large, longest axis 65-8lu, a average 3u. Microtectate, no columella ae (P) discernible, exine surface pitted, otherwise psilate Nenuber of species examined: 3 out of ca. 6. Plates: 22:11-12; 29:1. Goniothalamus ( Bl.) Hk.f. & Th. POLLEN MORPHOLOGY: Pollen grains in very loose tetrahedral to tetragonal tetrads. tamens septate, with — tetrad in a — compartment. Heteropolar, bilateral. Cataulcerate. Disc-like, concave-convex. Large, very large in G. curtisii (up to 140,), longest axis 71—140z, average 95u. Microtectate, no columellae discernible, exine surface often pitted, o' ilate. Number of species cena . out of ca. 80. Plates: 28:2—5; 29:2-4; 30:1-3. Richella A. Gray POLLEN MORPHOLOGY: Pollen grains in very loose tetrahedral to tetragonal tetrads. Stamens septate, with each tetrad in a separate compartment. Heteropolar, bilater Cataulerate Disc-like, concave-convex. Large, average longest axis 71y. Microtectate discernible, exine surface with some pits, otherwise psilate oa of species examined: 1 out of 1-2. Plates: 29:5; 30:4 THE ANNONA SUBFAMILY PoLLEN Morpuotocy: Pollen grains in tetrads or polyads (Cymbopetalum tribe ), rarely solitary (Isolona and Cleistochlamys of the Hexalobus tribe and a few Annona spp., Rollinia, and Rolliniopsis in the Annona tribe). Heteropolar (or apolar), bilateral (or radiosymmetric). Catasulcate to cataulcerate, rarely inaperturate (Isolona, Cleistochlamys, Annona spp.. 32 JAMES W. WALKER Rollinia, and Rolliniopsis). Boat-shaped-triangular, rounded, oblong, elliptic, or globose. Medium-sized to gigantic (rarely small—Cleistochla- mys), long axis measurement averages for the genera 24-183», average for the subfamily 83, (extreme length up to 350. in Cymbopetalum odoratissimum). Tectate-perforate to tectate, rarely intectate (in Trigynaea of the Cymbopetalum tribe ), perforations sometimes very large, up to 15p, columellae usually extremely well-developed to reduced, random to reticu- late to ornate. Exine often very thick, up to 20» thick in the Cymbopetalum tribe and more or less entirely wanting on the inner face of many mem- bers of this subfamily. This subfamily is notable because the pollen of the great majority of its members is either in tetrads or polyads (the Cymbopetalum tribe). The Cymbopetalum tribe is very remarkable for its almost constantly septate stamens with each polyad being in a separate compartment, for its pollen gigantism (up to 350), and for the almost total lack of exine on the proximal face of the grains. The genus Trigynaea of the Cymbo- petalum tribe is the only genus in the family which is definitely intectate. The subfamily is characterized by the extremely well-developed columel- lae which reach their peak in the Cymbopetalum tribe. THE HEXALOBUS TRIBE PotLEN MorpHoxocy: Pollen grains in tetragonal tetrads or solitary (Isolona, Cleistochlamys). Heteropolar (or apolar), bilateral (or radio- symmetric). Catasulcate to cataulcerate (inaperturate in Isolona and Cleistochlamys). Boat-shaped-triangular or globose. Large (rarely medium- sized or small—Cleistochlamys), long axis measurement averages for the genera 24-93, average for the tribe 60. Tectate-perforate or tectate, columellae distinct, random to reticulate. Diclinanona stands apart from the other genera in this group both phytogeographically and with respect to its floral morphology. Monodora Dun: POLLEN MORPHOLOGY: Pollen grains in tetrads. sey ape — teral. Catasuleate to cataulcerate (some Eom Boat-shaped to more or less triangular. Large (medium-sized at 30u ngolensis), longest pore 30-86z, — 65u. cigars some perforations aia ple not very prominent, columellae tinct, ran Number st species examined: 5 out of ca. 20. Plates: 28:6; 31:1. Isolona Engl. POLLEN MORPHOLOGY: Pollen grains solitary. Apolar, radiosymmetric. Inapertur Globose. Large, longest axis 52-65, average a Teotate, columellae palo, pis Number of species examined: 4 out of ca. 20. Plate Uvariastrum ae POLLEN MORPHOLOGY: Pollen grains in tetragonal tetrads. Heteropolar, bilateral. Catasulcate to rs Ss poet ape rennin. Large, longest axis 55-68, average 62u. Tectate-perforate, columellae distinct, ran Number of speci ed: 5 ben 6 x. 7. Plates: 29: nies 31 aes ANNONACEAE 33 Uvariopsis Engl. POLLEN MORPHOLOGY: Pollen grains in tetragonal tetrads. Heteropolar, bilateral. Cata- sulcate to cataulcerate. Boat-shaped-triangular. Large, longes axis 50-62u, average 56u. Tectate-perforate, columellae distinct (very well-developed in U. guineensis ), random. Number of species examined: 2 out of ca. 13. Plates: 31:3; 32:1-3. Hexalobus A. DC. POLLEN MORPHOLOGY: Pollen grains in tetragonal tetrads. Heteropolar, bilateral. Cata- sulcate to cataulcerate. Boat-shaped-triangular. Large, average longest axis 60x. Tectate-perforate, columellae very well-developed, reticulate. Number of species examined: 1 out of 5. Plates: 31:4-6; 32 4-5 Cleistochlamys Oliv. POLLEN MORPHOLOGY: Pollen grains solitary. Apolar, radiosymmetric. Inaperturate. Globose. Small, average longest axis 24y. Tectate, columellae distinct, well-developed, especially relative to grain size, some fused laterally into arcs, more or less random. Number of species examined: 1 out of 1. Plates: 32:6-9. Diclinanona Diels POLLEN MORPHOLOGY: Pollen grains in tetragonal tetrads. Heteropolar, bilateral. Cata- suleate to cataulcerate. Boat-shaped-triangular. Large, average ee axis 93 Tectate-perforate, columellae distinct, very well-developed, some fused laterally into arcs, etc., random. Number of species examined: 1 out of 2. Plates: 30:5; 32:10—-11. THE ASIMINA TRIBE PotteN Morpnoxocy: Pollen grains in tetragonal tetrads. Heteropolar, bilateral, Catasulcate to cataulcerate. Boat-shaped-triangular to oblong to rounded. Very large to large, long axis measurement averages for the genera 97-104y, average for the tribe 101p. Tectate-perforate, perfora- tions prominent, more or less circular to elongate to slit-like, up to 4-5 in Asimina and up to 9-12” in Deeringothamnus, columellae very well- developed, solitary or fused laterally, random to reticulate. Deeringothamnus with its strongly rounded grains with large, more or less circular perforations up to 12», and the strongly reticulate pattern of its columellae, is palynologically quite distinct from Asimina. Asimina Adans. POLLEN MORPHOLOGY: Pollen grains in tetragonal tetrads, longest tetrad axis 120—180u. Heteropolar, bilateral. Catasulcate to cataulcerate. Shape varied, from boat-shaped- triangular to oblong to rounded. Very large to large, longest axis 84-1]l4u, average 104u. Tectate-perforate, perforations prominent, up to 4-5u, more or less circular to elongate to slit-like, columellae very well-developed, solitary to fused laterally into arcs various ornate patterns, more or less random to reticuloid, moderately packed to tightly packed. Number of species examined: 8 out of 8. Plates: 30:6; 33:14; 34:1-6; 35:1-5; 37:3. Deeringothamnus Small POLLEN MORPHOLOGY: Pollen grains in tetragonal tetrads. Heteropolar, bilateral. Cataul- cerate. Oblong to rounded. Large to very large, — axis 90-103u, average 97x. i ongate, very large—up to 9-12y, columellae very well-developed, mostly solitary, a few fused laterally into arcs, etc., reticulate. Number of species examined: 2 out of 2. Plates: 35:6; 36:1-6; 37:1-2. 34 JAMES W. WALKER THE ANNONA TRIBE PoLLEN MorpxHoxocy: Pollen grains in tetragonal tetrads to solitary (a few Annona spp., Rollinia, Rolliniopsis). Heteropolar or apolar, bilateral or radiosymmetric. Catasulcate, cataulcerate, or inaperturate (a few Annona spp., Rollinia, Rolliniopsis ). Oblong, elliptic, rounded, or globose. Gigan- tic to medium-sized, long axis measurement averages for the genera 49- 107, average for the tribe 68. Tectate-perforate to tectate, columellae well-developed to faint, random to reticulate or ornate. The genus Raimondia (exclusive of R. tenuiflora) is palynologically somewhat distinct within the tribe, especially with regard to its prominent tectal perforations. The solitary grains found in Rollinia, Rolliniopsis, and the more ad- vanced, West Indian species of Annona are clearly secondary and derived from grains which were in tetrads. This is a noteworthy reversal of the normal trend from solitary grains to tetrads. Asnoun BE: Number of species mates 50 out of ca. 125. Plates: 33:5-12; 37:4—5; 38:1-6; 39: shi 40:1-6; rei 1-6; 42:1-6; 43:1-12. sais 1, Annona POLLEN MORPHOLOGY: tetragonal tetrads, longest tetrad axis 200 more than 300z. tla fail Catasulcate to cataulcerate. Oblong = elliptic to round e to gigantic, axis urement bio for species circular, some elon ng. minute to large, columellae very well-de Bee sap solitary or wire | a few less reticu Number yp species examined: 4 out of 17. Plates: 33:5; 38:1-2; 39:1-3. Sect. 2. Macrantha R. E. Fries This section, with 3 species, is endemic to South America. No species were examined. Sect. me Ulocarpus Saff. pence of species examined: 2 out of 2. Plates: 39:4. ect. 4. coo: R. E. Fries POLLEN MORPHOLOGY: oe in tetragonal tetrads. Heteropolar, bilateral. Cata- sulcate to cataulcerate. soli: ed to dilene: Very large, average longest grain axis for the section 159u. Tectate- te, perforations relatively small, usually less hei the diam Soy columellae, aa ellae well-developed, mostly solitary, medium- packed, more or less random to loosely reticulate. Number eg species examined: 1 out of 2. Plates: 38:3; 39:5-6. ANNONACEAE 35 Sect. 5. , Pasmamaginis Saff. POLLEN MORPHOLOGY: Pollen grains in tetragonal tetrads. Heteropolar, — Cata- sulcate to gy ag ee ed to oblong. Gigantic, average longest grain axis for the sectio Tectate-perforate, columellae well-developed, mostly solitary, Eiki thaws or less random. Number of species examined: 1 out of 3. Sect. 6. Phelloxylon Saff. POLLEN MORPHOLOGY: Pollen grains in tetragonal tetrads. Heteropolar, ese Cata- sulcate to cataulcerate. Rounded to oblong. Very large, goa ge — t grain axis for the section 111. Tectate-perforate, perforations rather small, more or less circular, columellae well-developed, highly ornate, Bret cobiielled ca tael only. Number of species examined: 1 out of 1. Plate Sect. 7. Tee Saff. POLLEN MORPHOLOGY: Pollen grains in tetragonal tetrads. So ape bilateral. Cata- pases i cataulcerate. Rounded to oblon ng. M Medium-sized to —_* very large, long axis urement averages for the species 49-14]ly, average paca section 89u. sotate, fs tectate-perforate, perforations small, columellae all Slaleped, st to a few fused laterally, random to highly reticu ulate. Number of species examined: 4 out of 9. Plates: 33:6-7; 41:1-3. Sect. 6. Pilannona Saff. LEN MORPHOLOGY: Polle ins in tetragonal tetrads. Heteropolar, bilateral. Cata- Per to aieeloarais cain enidate be inaperturate in A. jamaicensis). Rounde to oblong to globose (A. jamai icensis). Very large, long axis measurement averages for the species 102—156u, average for the jock 1204 (med Diniicabedl in A. jamaicensis, average a, 0 abil axis 37~). Tectate : ee ee SS enarr — the wor species of the ection in bic’ type, grain shape an Number of species seis 9 out of 24. Plates: 33:8; 37:4-5; 40:5— Sect. 9. Gamopetalum Saff. POLLEN MORPHOLOGY: Pollen grains in tetragonal tetrads. Heteropolar, bilateral. Cata- sulcate to cataulcerate. Rounded to oblong. Very large, long axis measurement averages for the species 116-118, average for the section 117. Tectate-perforate, perforations small, columellae well-developed, vy th oy packed, solitary to fused laterally into ornate patterns, random to so ain to Number of sp mined: 2 out of 7. ma 38:4; 41:4. Sect. 10. Oligantha R. E. Fries MoRPHOLOGY: Pollen grains in tetragonal Leger sign re bilateral. Cata- sulcate to cataulcerate. Rounded to oblong-elliptic ge, long axis measurement averages for the species 40-79u, average for the satire oa Tectate, — — numerous, more mostly so umber of s ned: out of 10-11. ates: none (but see pl. 44:10, ud goaee which ene REN looks like a member of this section). Sect. 11. Atractanthus Saff. EN MORPHOLOGY: Pollen grains in tetragonal tetrads. Heteropolar, bilater. - — nose to cataulcerate. ‘Henle to oblong. Medium-sized to large, long axis m ment averages for the — 40-64, average for the section 53. Tectate, ckonialias pe mi eloped, reticulate. Number of species examined: 3 out of 5. Plates: 33:9-12; 41:5; 42:1-4. Sect. 12. Atta Mart. MoRPHOLOGY: Pollen grains in tetragonal tetrads. Heteropolar, bilateral. Cata- eee to cataulerate to cataceroidate Rounded to oblong. Medium-sized to large, ng axis measurement ica r the species 32-74u, average for the section 57x. Tectate, Fe I well-d a leg guess to loosely reticuloid. Number of species ied a out of 12. Plates: 38:5; 41:6; 42:5-6; 43:1. 36 JAMES W. WALKER Sect. 13. Chelonocarpus Saff. EN MORPHOLOGY: Pollen grains in tetragonal tetrads. Heteropolar, bilateral. Si i re to cataulcerate. Rounded to oblong. Large to very large, long axis ent averages e species 91-101u, average for the section 964. Tectate- periar naar calle Ilae well-developed, solitary to ornate to reticulate. ‘umber of species examined: 2 out of 4. Plates: 38:6; 43:2-3. Sect. 14. Ilama Saff. POLLEN MORPHOLOGY: Pollen grains in tetragonal tetrads. Heteropolar, bilateral. Cata- sulcate to cataulcerate. Rounded to oblong. Large, long axis measurement averages for the species 72—76u, average for the section 74u. Tectate, columellae mostly random, mainly solitary. Number of species examined: 2 out of 2. Plates: 43:4—-5. Sect. 15. Saxigena Saff. POLLEN MORPHOLOGY: Pollen grains in very loose tetragonal —— to feos Apolar, radios etric. Inaperturate. Globose. Medium-sized, long axis meas ent averages for the species 30-32u, average for the section 3ly. Tabtats ihcaicce reduced, random Sondes of species examined: 2 out of 2. Plates: 43:6—-7. Sect. 16. Annonula Saff. POLLEN MORPHOLOGY: Pollen grains in tetragonal tetrads or solitary. Heteropolar to apolar, bilateral to radiosymmetric. satan erate to cataulceroidate to inaperturate Globose to oblong. Medium-sized, lon s measurement averages for the species 34— 48u, average for the section 43u. iis ag columellae reduced, random Number of species examined: 4 out of 11. Plates: 43:8 Sect. 17. Annonella Baill. LEN MORPHOLOGY: Pollen grains solitary (rarely in loose tetrads). Heteropolar to ster a bilateral to radiosymmetric. Cataulceroidate to inaperturate. Globose to oblong. Medium-sized to large, long axis measurement averages for the species 42- 53u, average for the section 474. Tectate, columellae distinct, random to somewhat reticulate. Number of species examined: 4 out of 5. Plates: 43:9-12. Rollinia St Hil POLLEN MORPHOLOGY: Pollen grains solitary. Apolar, radiosymmetric. Inaperturate Globose. Medium-sized . ee lon ae axis 35-62u, average 49u. Tectate, colomelias disti random to somewhat i, Number of species examined: 7 out of ca. 65. Plates: 44:1-6; 45:1-4. Rolliniopsis Saff. POLLEN MORPHOLOGY: Pollen grains solitary. sg ser radiosymmetric. Inaperturate. Globose. shat cntiaked: average Pistia axis 50u. Tectate, columellae distinct, random. Number of species examined: 1 out of 4. Plates: 44:7; 45:5. © ummisemns Saff. er, ran om.) e exine structure of R. tenu pers is e other we caties Fries is probably correct in transferring this species ony to Annona section Oligantha), with which it is palynologically more harmonious (cf., Annona section Oligantha). Number of species examined: 4 out of 4. Plates: 44:8-10; 45:6; 46:1. ANNONACEAE HY f THE CYMBOPETALUM TRIBE PotLEN Morpuoxocy: Pollen grains in polyads (octads in Cymbopetalum, Cardiopetalum, Trigynaea, and Disepalum; 16's in Hornschuchia; and 16’s, 18's, 20’s, 24’s, etc. in Porcelia). Stamens transversely septate at maturity with each polyad in a separate compartment (except in Disepa- lum). Heteropolar, bilateral. Cataulcerate. Rounded to oblong. Large to gigantic, long axis measurement averages for the genera 64-183, average for the tribe 104y. Tectate-perforate or intectate (Trigynaea), perforations sometimes very large, up to 15y, columellae extremely well-developed, random to reticulate, exine very well-developed, often more than 20n thick, more or less entirely wanting on the inner face. This tribe is very distinctive in that its pollen always occurs in polyads and all its members except Disepalum have septate stamens at maturity, with each polyad in a separate compartment. This group is remarkable for its very large pollen (up to 350 in Cymbopetalum odoratissimum), which is more or less devoid of exine on the proximal face. Trigynaea is the only genus in the family definitely with intectate grains (clavate or baculate). Disepalum stands somewhat apart within the tribe in being the only non-American genus, in lacking transversely locellate stamens at maturity, in having a single, basal ovule, and in its bracteate peduncle. Cymbopetalum Benth. longest axis 130-283, average 1834 (some grains in C. odoratissimum up to mu). Tectate-perforate, perforations sometimes very large, up to 15y, columellae extremely well-developed, in arcs or solitary, random to reticulate, exine very well-developed, often more than 20x thick, frequently entirely wanting on inner face, intine thick and a polyad. Sculpturing (in C. odoratissimu ooth tec large, more or less rounded to elongate to irregular perforations, nexine surface on the proximal face wrinkled, rough. Number of species examined: 10 out of ca. 13. Plates: 46:2-5; 47:1-6; 48:1-5; 49:1-2; 59:3; 60:3-5; 61:1-2. Cardiopetalum Schlecht. POLLEN MORPHOLOGY: Pollen grains in polyads (octads). Stamens transversely septate with each polyad in a separate compartment. Heteropolar, bilateral. Cataulcerate. on inner face. Number of species examined: 1 out of 1. Plates: 46:6; 48:6; 50:1-2. Porcelia Ruiz & Pav. POLLEN MORPHOLOGY: Pollen grains in polyads (16's, 18’s, 20's, 24’s, etc.). Stamens transversely septate with each polyad in a separate compartment. Heteropolar, bi- lateral. Cataulcerate. Rounded to more or less oblong. Large to very large, longest axis 68-125u, average 90u. Tectate-perforate, rforations mostly circular, medi m- to small, columellae well-developed, mostly solitary, somewhat reticulate, exine well-developed, more or less wanting on inner face. Number of species examined: 4 out of 5. Plates: 44:11; 49:3-5; 50:3-4. 38 JAMES W. WALKER Trigynaea Schlecht. POLLEN MORPHOLOGY: Pollen grains in polyads (octads). Stamens transversely septate — aig a separate on pgrigieior Heteropolar, bilateral. Cataulcerate. Ro . Large, longest axis 56-7lu, average 64y. Intectate, baculate (T. caudata, T: Reda ent or clavate (T. oblongifolia). Exine well-developed, more or less want- ing on inner face. Number of species examined: 3 out of 5. Plates: 44:12; 49:6; 50:5-6; 51:1; 52:1-2; 53:1-2 Hornschuchia Nees von Esenbech POLLEN MORPHOLOGY: Pollen grains in polyads (16's). Stamens keen septate with each polyad in a separate compartment. Heteropolar, bilateral. Cataulcerate. Bounes, ig hai average longest axis 84u. Tectate-perforate, perforations rounded to so: elongate-irregular, columellae well-dev paige mostly solitary, reticulate, exine eel developed, more or less wanting on inner eu r of species examined: 1 out of 3. Plates: 52:3; 53 _ Disepalum Hk.f. cerate. Mounted to oblong E arge to very large, ongest axis 68-127, average 96u Tectate-perforate, perforations medium to small (very large in D. anomalum), rounded to shortly elongate, Sagar hdd faa solitary to fused laterally into arcs, random to reticulate, exine well-developed, more or less — on inner face. Number of species examined: 5 out of ca. ae ota 51:2-6; 52:4-7; 53:4-6; 54 CRITIQUE OF RECENT PALYNOLOGICAL STUDIES As mentioned earlier, the only recent, extensive survey of the pollen of the Annonaceae is that of Canright (1963). His study includes pollen from 186 species in 71 genera and was based upon acetylated grains. The present study has brought to light certain differences with the observations and/or conclusions made by Canright. He states that only 11 genera were found with tetrads, while in the present study some 20 genera were found to be characterized by tetrads, many of which were undoubt- edly included in his study. No mention is made in Canright’s paper of polyads, while in the present study six genera were found consistently with polyads and a seventh (Xylopia) was found to have either tetrads or polyads, depending on the species. Disepalum is listed by Canright among the genera with tetrads, while all species of this genus examined in the present study were found to have polyads (octads). Fissistigma is listed among the genera with tetrads by Canright, while all examined species were found to have solitary grains in the author’s study. Also, he lists Cremastosperma among the genera with tetrads. All nine species examined in the present study were found to have solitary grains. A very few rare tetrads (or possibly only chance tetrad-like aggregates) were found in some slides of C. cauliflorum (pictured by Canright), but, in my opinion, to list a genus as having tetrads when they may only occur rarely in one species is somewhat misleading. The tetrads that Canright found were tetragonal or rhomboidal, but not tetrahedral. From the present study the fact emerges that Pseuduvaria, Mitrephora, and Pseudoxandra are characterized by tetrahedral tetrads, even though the majority of the annonaceous tetrads are of the tetragonal type. Canright states that all examined species were characterized by ANNONACEAE 39 either a monosulcate or inaperturate condition. However, I have found disulculate pollen in Guatteria, Guatteriopsis, Heteropetalum, and Sap- ranthus. The occurrence of disulculate pollen in Guatteria is statistically significant for the family at the species level since Guatteria is the largest genus with some 250 species. The discovery of disulculate pollen in the family also negates Canright’s position relative to the relationship of the Eupomatiaceae to the Annonaceae. Canright lists Cymbopetalum among genera having the smallest grains in the family (around 20»), when in actuality this genus probably has the largest, fixiform pollen in the angiosperms with an average of the longest grain axis for the genus of 183, and a range of averages for the species from 130-283, (based upon a study of 10 species out of a total of 13 for the genus). He describes the pollen of Cyathocalyx and Drepananthus as monosulcate although all species of these two genera examined by the author were found to be inaperturate. Finally, Canright lists M onodora as having coherent, inaperturate tetrads and Isolona as having solitary, monosulcate grains. The species of the two genera examined in the present study showed Monodora to have monosulcate grains in tetrads, while the grains of Isolona were found to be solitary and inaperturate. He additionally concludes that Monodora and Isolona are not closely related, based upon palynological data. This is not borne out by the present study, since a number of examples were found in which one genus of a closely related pair had monosulcate tetrads, while the pollen in the second genus was reduced to solitary, inaperturate grains, e.g., Hexalobus and Cleistochlamys; Annona and Rollinia. Major TRENDS OF POLLEN EVOLUTION The most important phylogenetic character of pollen morphology is the type of aperture, while polarity, symmetry, and shape are all more or less dependent upon the aperture type. The pollen-unit and exine structure and sculpturing are also of great phylogenetic significance. Palynologically the Annonaceae may be divided into a number of rather distinct groups based primarily upon the type of aperture (table 6). For the most part these groups (based primarily on pollen morphology) are much more natural than the previously recognized infrafamilial groups (based entirely upon floral morphology ). An outline of aperture evolution within the family has been given (table 3) and is reviewed in plate 55. It must be emphasized that plate 55 is only a chart of pollen trends and should not be interpreted as a phylo- genetic diagram. The primitive aperture type for the family is clearly the anasulcate grain, which is so common in many of the other “ranalean families, especially in the closely related Magnoliaceae ( Canright, 1953) and Canellaceae ( Wilson, 1964). Two species of the genus Pseudoxandra appear to be the only members 40) JAMES W. WALKER TABLE 6. PALYNOLOGICAL CLASSIFICATION OF THE ANNONACEAE I. SULCATES, ECHINATES, INAPERTURATES, AND DISULCULATES A. SULC Neilston Pseudoxandra (some catasulcate ). Catasulcates: gratia! sao almea Ephe edranthus, Pseudephedranthus, Ox- andra, Ruizodendron, Unono , Bocageopsi is, Onychopetalum, Enantia, Polycerato- cap. Soa (a few sabeain “Polyalthia (a few sulcate ), whit (a few sulcate ), Monoc : Monanthotaxis, Enneastemon, Popowia (African), Desmos, Dasymas- dala. Friesodielsia ‘Diese opsis, Stenanona, Reedrollinsia, Tetrameranthus, Duguetia, Cleistopholis, Friesodielsia (African), Uvaria (a few sulcate), Anomianthus, Tetra- petalum, Ellipeia, Cyathostemma, Rauwenhoffia, Enicosanthum, Sageraea, Stelecho- carpus, Trivalvaria, Polyalthia (a few sulcate), Mezzettia, Chieniodendron, Artabotrys (a few sulcate), Cyathocalyx, ib rr mae Meiogyne, Oncodostigma, Guamia, Papualthia, Woodiella, Fissistigma, Mitrella Melodoru um, Alphonsea, Miliusa, Sacco- petalum, Phaeanthus, Orophea, Platymitra, Mitrephora, Pseuduvaria, Popowia, Neou- varia D. DISULCULATEs: Sapranthus, Guatteria, Guatteriopsis, Heteropetalum. II. CATAULCERATES EA-TYPE CATAULCERATES: Anaxagorea, Piptostigma, Neostenanthera, Xylopia, he Fusaea, Seagate Cananga, Goniothalamus, Richella. pets oad CA xalobus att UG eadesticen! Uvariopsis, Cleistochlamys, Hexalobus, Monodora, tien Diclinanona. i roup: Asimina, Deeringothamnu Annona Group: Annona, Raimondia, Ri ollini a, Rollinio cp op opsis Cymbopetalum obi Cymbopetalum, ChidinpeeaRinn: Porcelia, Trigynaea, Horns- chuchia, Disepalum of the family to have retained the distally oriented sulcus. Other species of this genus show the transition from anasulcate to catasulcate and it is probably best to consider the other closely related genera such as Malmea, Cremastosperma, Unonopsis, et al. as catasulcate also, although future cytological studies may show them to be anasulcate. If the Malmea sul- cates should prove to be anasulcate, then the majority of the inaperturates (and all the disulculates) would be derived directly from an anasulcate, rather than a catasulcate ancestry. From this basal group of catasulcates a number of radiations occurred (pl. 55). In one line the sulcus was lost and the grains became inapertur- ate. Through parallel evolution from two separate inaperturate groups disulculate grains developed. In both groups this type of aperture is corre- lated with a highly reduced exine. Two other groups developed highly distinctive echinate or microbaculate pollen, the first (Desmos and its allies) retaining a sulcus in some members, the second (Monanthotaxis and its allies) being inaperturate. From the basal catasulcate group of genera with moderately well- developed columellae two other parallel but quite distinct lines emerged. They are both characterized by trends toward pollen gigantism, toward the production of tetrads and polyads, toward the formation within the stamens of sterile septa enclosing each tetrad or polyad in a separate ANNONACEAE 41 compartment, and toward the formation of a cataulcus rather than an elongate sulcus. These two lines, however, exhibit two opposite trends relative to the columellae and the surface of the tectum. In the one group, the Fusaea- type cataulcerates, the columellae are so highly reduced as to be indis- cernible, while in the other, the Annona-type cataulcerates, the columellae are enlarged to gigantic dimensions (sometimes up to 10» wide ). Finally, the medium-sized tectal perforations of Malmea-Cremastosperma are tre- mendously enlarged in the Annona group (up to 154), while they become highly reduced in the Fusaea group. The Annona and Fusaea groups both exhibit a strong trend toward more and more loss of the exine on the inner face of the grain, until the exine is more or less entirely lacking on the proximal side in some genera, e.g., Cymbopetalum. Interestingly enough, the sculpturing trends quite closely parallel the trends in apertures, pollen-units, and exine structure (the columellae ). Plate 56, which is made up of a series of scanning electronmicrographs, shows the four major sculpturing trends. The moderate-sized perforations in the tectum of such genera as Malmea and Cremastosperma (pl. 56: 1a) are considered basic for the family. One line continues this pattern (pl. 56:1b). A second line shows the loss of most of the tectal perforations, with the tectum becoming subverrucate (pl. 56:2a) to strongly verrucate (pl. 56:2b) to echinate (pl. 56:2c). A third line, which characterizes the Fusaea-type cataulcerates, exhibits a reduction in the perforations (pl. 56:3a) and finally an almost total lack of them (pl. 56:3b and 3c). The fourth line, which characterizes the Annona-type cataulcerates, exhibits a great elaboration of the perforations in the tectum (pl. 56:4). It is interesting to note that while the genus Pseudoxandra clearly has a most primitive aperture type within the family, it is already somewhat specialized with regard to exine sculpturing and structure and clearly shows a tendency toward the exine type found in the Fusaea group. Table 7 summarizes the primitive and advanced pollen characters for the family. SELECTIVE VALUE (ADAPTIVE SIGNIFICANCE ) OF POLLEN CHARACTERS Like most other features of the plant, the majority of pollen characters are probably the result of natural selection. In some instances, support may be found for a certain hypothesis concerning the selective value of a given pollen character by use of correlation studies, as was done by Grant (1950) with regard to the evolution of epigynous flowers. In other cases actual experiments may be conducted to determine the selective value of a pollen character ( Whitehead, 1969). However, the determination of the selective value of some characters may not be open to experimentation, and their selective value may always be a matter of question and debate. The following discussion consists mainly of suggested selective values for certain pollen characters and is intended primarily to provoke further TABLE 7. PRIMITIVE AND ADVANCED POLLEN CHARACTERS IN THE ANNONACEAE PRIMITIVE CHARACTERS ADVANCED CHARACTERS POLLEN-UNITS Solitary grains pee solitary Tetrads Polyac nthers without sterile septa Sattied! with sterile pain with sterile septa initia uly septa at matu rity POLARITY Grains isopolar Grains heteropolar ——————— Grains apolar SYMMETRY srains asymmetric-fixiform Grains bilateral Grains bilateral ———————— Grains radiosymmetric APERTURES Inaperturate Anatrichotomosulcate Cataulcerate Disulculate Anasulcate Catasulcate Inaperturate SHAPE itl concave- onvex Boat-shaped eae ar Si a Rounded SIZE 25-60 u 60-804 aa 80-350u STRUCTURE AND Microtectate SCULPTURING | Tectate Tectate-perforate I ntectate Tectal perforations reduced Tectal perforations medium- sized Tectal perforations g enlarged Columellae reduced Columellae Columellae moderate-sized indiscernible Columellae large Columellae ornate Columellae random and solitary Columellae reticulate Exine extremely reduced Exine moderately thick Exine greatly thickened Exine even Exine subsaccate Exine perisaccate Exine covering the grain Exine lacking on proximal fa Sculpturing more or less psi- — Sculpturing foveolate. late, with tectal perforations scabrate, clavate, etc. ANNONACEAE 43 discussion. It is hoped that it may lead to future experimentation which may give quantitative answers for some of the proposed hypotheses. From a survey of the genera and families of angiosperms in which pollen tetrads and polyads occur (table 1), it appears that the evolution of these pollen-units correlates significantly with a high ovule number per ovary.11 The only two angiosperm families which have pollinia (the Orchidaceae and Asclepiadaceae) are both characterized by having numerous seeds per ovary. In the Orchidaceae especially, the number of seeds per capsule reaches fantastic proportions. The Ericaceae, which is a family well-known for its pollen tetrads, is also well-known for its numerous, small seeds. Within the Annonaceae this correlation is quite evident. For example, in the related genera Anaxagorea and Xylopia, the former has solitary pollen and two ovules per carpel, while the latter has pollen in tetrads or polyads and several to many ovules per carpel. Another example of the connection between ovule number and the occurrence of tetrads may be seen in the two closely related genera, Hexalobus and Cleistochlamys. Hexalobus has numerous ovules and cataulcerate tetrads, while in Cleis- tochlamys the ovule number has been reduced to one per carpel and the pollen grains have become solitary and inaperturate. It is clear that the single, basal ovule in each carpel of the genus Annona represents an end line from ancestors that had numerous ovules in each ovary. It is interesting in this connection to note that there is a progressive trend within the genus toward the reduction of the tetrads and their final loss with the development of inaperturate, solitary grains in the advanced West Indian species of Annona. The two closely related, uniovulate genera, Rollinia and Rolliniopsis, produce only solitary grains. The most dramatic correlation of high ovule number with large pollen- units is seen, however, in Cymbopetalum and its relatives. Here, fruits with numerous seeds reach some of the greatest dimensions in the family. In this group of genera the occurrence of polyads is a constant feature, with one genus having as many as 24 pollen grains in a single unit. There is no apparent reason why septate stamens should be constantly correlated in the family with tetrads or polyads, but the fact that the stamens of the genera of Mimosoideae with polyads are also septate speaks for a common basis, if nothing more than developmental necessity. The initial evolution of the pollen aperture itself was certainly in response to the need for a more efficient means of exit for the germinating pollen tube; but, as Wodehouse (1935) has pointed out, the aperture also serves a harmomegathic function in permitting changes in the volume of the grain with varying humidity. The original monosulcate grains were rather limited in this latter respect according to Wodehouse, who saw the development of the basic tricolpate pollen of the angiosperms as. - . 11This idea was first suggested to the author by Dr. James A. Doyle. 4 JAMES W. WALKER (Wodehouse, Pollen Grains, pp. 330-331 ) However, another equally important reason for the development of tricolpate and multi-furrowed, multi-pored grains may be given. In the ymnosperms with their unenclosed ovules and pollination droplet the direction of the germinating pollen tube was probably not very critical due to the moist environment of the pollination chamber. The orientation of the pollen grain on the stigma of an angiosperm, however, would seem to be of some concern. Even with stigmatic papillae, it would appear likely that those pollen grains with the pollen tube germinating in the direction of the stigmatic surface would be favored. A monosulcate, boat- shaped grain could easily germinate in the direction away from the stig- matic surface and perish from the lack of moisture, while a tricolpate, more or less globose grain would appear to have a better chance of germinating near the stigmatic surface and hence of avoiding desiccation. The trend within the Annonaceae toward the loss of exine on the proximal face of the grains in the polyads of Cymbopetalum and its relatives would appear to lend support to this idea. With a polyad of over 400, as in some species of Cymbopetalum, one can readily see the disad- vantage of pollen tubes germinating in all directions in the air and the advantage of the lack of exine on the inner faces of the grains, with the contiguous intine providing a moist, internal milieu for the downward germination of the mass of pollen tubes. This idea could easily be followed up and verified in the field. Since grain polarity, symmetry, and shape are all more or less tied up with aperture type, they will not be discussed independently. The size of pollen grains appears to be most closely related to the means of pollination—whether by insects (entomophily) or wind (ane- mophily). Whitehead (1969) says that the syndrome of an anemophilous plant includes the production of large numbers of pollen grains, pollen grains with thin exine and smooth sculpturing, and grains in the size range of 20-40». Grains larger than 40» drop too soon in air currents, while grains less than 20» are swept around the stigma and fail to be caught on the receptive stigmatic surfaces. e large size of most annonaceous pollen with its sometimes enor- mously thick, highly sculptured exine suggests a high degree of insect pollination. Field studies on the pollination mechanisms in the family would be of high interest in light of the information now known concern- ing trends of specialization of its pollen. The means of pollination in the genus Guatteria, with its highly reduced exine and disulculate grains, ANNONACEAE 45 should be of particular concern to future field workers. The grains of this genus are remarkable for a non-aquatic, tropical tree because of the extremely reduced exine. Whatever the pollination method, it must be eminently successful since Guatteria, with its 250 species, is the largest genus in the family. In general, wind pollinated species have smooth, dry pollen, while entomophilous plants have highly sculptured, oily pollen grains. It would appear that the most significant selective value of sculpturing is simply its presence and that the myriads of diverse sculpturing types (clavate, verrucate, echinate, etc.) all represent different ways of accomplishing the same goal, namely, the transfer (via insects) of a limited number of pollen grains from a stamen to a stigma with least loss and with the high- est degree of efficiency. The fact that oily, highly sculptured pollen grains tend to stick together in masses would also be of selective value in such highly specific pollination methods as certain forms of entomophily. The selective advantage of internal structural differences (columellae arrangements, etc.) is hard to visualize, but may be related to the devel- opment of more effective supporting devices for the tectum and its sculp- turing elements. PHYTOGEOGRAPHY The family Annonaceae is a predominantly tropical group of some 130 genera and approximately 2,300 species. There are three centers of distri- bution among which the genera are more or less evenly divided—America, with some 36 endemic genera, Africa (including Madagascar) with some 40 endemic genera, and Asia with approximately 50 endemic genera (cf., table 8). One genus occurs in all three centers (Xylopia), three occur in both Asia and Africa (Uvaria, Polyalthia, Artabotrys), one is found in both Asia and America (Anaxagorea), and one in both Africa and America (Annona). Both floral morphology and pollen morphology provide strong evidence for the origin of the family Annonaceae in the American tropics (or possibly Africa), with the major center in the Amazon Basin and a secondary center in Central America. Outlying areas of distribution include the islands of the West Indies, the drier regions of southern Brazil, Paraguay, and (rarely) Argentina, and the drier parts of Central America and Mexico. Eastern North America is another outlying area of distribution with two genera, Asimina and Deeringothamnus. Of the 10 recognized palynological groups within the family (consider- ing the Fusaea group as one), nine are found in the American center o distribution, while six are either endemic or have the majority of their members in the New World (cf., table 9). Africa has only one palynolog- ical group with most of its members found there (the Hexalobus group), while Asia has only two groups (the echinates and inaperturates) with the majority of their members endemic or highly restricted to the Asian region. 46 JAMES W. WALKER TABLE 8. GEOGRAPHICAL DISTRIBUTION OF THE GENERA OF THE ANNONACEAE AMERICA (36-593) * , Ps andra 6, Oxandra 25, Ruizodendron 1, Unonopsis 33, Bocageopsis 3, Onychopetalum 4, Desmopsis 16, Stenanona 2, Reedrollinsia 1, Sapranthus 12, Tridimeris 1, Tetra- meranthus 2, Duguetia 74, Guatteria 250, Guatteriella 1, Guatteriopsis 4, Hetero- petalum 2, Duckeanthus 1, Fusaea 3, Diclinanona 2, Asimina 8, Deeringothamnus 2, Raimondia 4, Rollinia 65, Rolliniopsis 4, Cymbopetalum 13, Cardiopetalum 1, Froesiodendron 2, Porcelia 5, Trigynaea 5, Bocagea 2, Hornschuchia 3. AFRICA (40-255) Enantia 10, Pachypodanthium 3, Polyceratocarpus 8, Cleistopholis 4, Friesodielsia** 15, Monanthotaxis 4, Enneastemon 10, Popowia** 65, Gilbertiella 1, Atopostema 2. Exellia 1, Xylopiastrum 1, Balonga 1, Letestudoxa 2, Afroguatteria 2, Toussaintia 3, Dielsiothamnus 1, Fenerivia 1, Pseudartabotrys 1, Greenwayodendron 2, Lettowi- asta (50-662 ) Desmos 25, Dasymaschalon 12, Friesodielsia** 40, Anomianthus 1, Tetrapetalum 2, i iopsi thostemm AMERICA, AFRICA, AND ASIA (1-170): Xylopia 170. AFRICA AND ASIA (3-425): Uvaria 175; Polyalthia 150; Artabotrys 100. AMERICA AND : Anaxagorea 29. ‘A AND AFRICA (1-125): Annona 125. *Number of genera and approximate number of species. +Approximate number of species. **Popowia and Friesodielsia, as presently constituted, have species in Africa and Asia. However, there is good evidence that four genera instead of two are involved and that none of them occur both in Africa and in Asia. The rare and very primitive pollen type within the family that has retained the sulcus on the distal face (anasulcate) is entirely New World, while the great majority of the sulcate types of the primitive Malmea tribe (presumably catasulcate) are American (10 genera with some 100 species ). There is only one African genus (Enantia) in this tribe. By contrast the Uvaria tribe, with its advanced inaperturate and echinate pollen types, is heavily represented in Asia and to a lesser degree in Africa. Of 47 inaperturate and echinate genera in this tribe, only five are American. The Guatteria tribe with its disulculate pollen is entirely American, while the whole Annona subfamily is decidedly American with the excep- tion of the Hexalobus tribe. The Fusaea subfamily is more or less evenly distributed among the three centers of distribution. However, within the bicentric genus ANNONACEAE 4 Pollen Type New World Asia Africa Anasulcates (I) ~ | _ Catasulcates (12) a a is Echinates (6) a cl Inaperturates (41) ‘nse = — Disulculates (4) 6 Cataulcerates Fusaea-type Anaxagorea & Piptostigma (2) fa ‘soma “eae Xylopia (1) E | - A] fee : oniothalamus TOE i eee Ms een = Annona-type Hexalobus Group (7) — a Asimina Group (2) a Annona Group (4) a “nese Cymbopetalum Group (6) | ae * number of genera TABLE 9. GEOGRAPHICAL DISTRIBUTION OF ANNONACEOUS POLLEN TYPES 48 JAMES W. WALKER Anaxagorea, not only the bulk of the species are American rather than Asian (23 species versus 6 species), but the American species also have the most primitive stamens in the family (laminar and leaf-like ). Thus, the American center is characterized not only by having the over- whelming majority of primitive pollen types, but by having the greatest diversity of pollen types within the family as well.1? By contrast the Asian genera are almost all highly specialized palynologically (and florally ),* the great majority having inaperturate or echinate pollen. There is only one sulcate genus in Asia other than the fusaeoid genus Anaxagorea, and it is monotypic and advanced (M onocarpia). The entire Annona subfamily has only a single Asian genus (Disepalum) with some eight species, and this genus is highly advanced even within the Annona subfamily. It was a surprise to the author to come to the conclusion that the Annonaceae were of New World (and/or possibly African ) origin in light of the fact that the great majority of primitive angiosperm families are clearly of an Asian or Australasian origin.'* Palynologically, the African genera are more diverse than those of Asia, which are for the most part rather monotonous with their predominantly inaperturate type of pollen. It appears as if a number of different groups reached Africa from the main center of evolution in South America, although they may possibly represent relic groups from the original center of origin. However, the bulk of Asian genera seems to represent an adaptive radiation from one or a few closely related types. Finally, mention should be made of the strong representation of the Hexalobus tribe of the Annona subfamily in Africa and Madagascar. Thus, Africa has a high number of what may be relic genera, and since material of some 21 African genera was not available at the time of the present study, one cannot rule out the possibility of Africa or Africa~South America (with subsequent continental drift) as being the primary center of origin for the family, rather than South America alone. One can, how- ever, state with some confidence that the data from both pollen and floral morphology preclude an Asian-Australasian origin for the family. Finally, it is interesting to note that the three closely related families, Annonaceae, Canellaceae, and Myristicaceae (which I recognize as the order Annonales), all appear to have a neotropical and/or African origin, ike most other “ranalean” families, such as the Magnoliaceae, Wintera- ceae, Degeneriaceae, etc. The Canellaceae is entirely American-African with no Asian representatives, while the Myristicaceae are more or less 12The author agrees with Smith (1967) that both the morphological diversity and comparative Primitiveness within such families as the Winteraceae, Magnoliaceae, Illiciaceae, Schisandraceae, an imiaceae are greater among the Asian representatives than among those of America; how- ever, strong exception must be taken to his inclusion of the Annonaceae in the above list of families. 18It is surely not an insignificant fact that a great number of Asian Annonaceae are climbers. whereas a scandent habit is almost unknown in the American species. 14In this connection it was of some interest to discover that Ehrendorfer et al. (1968), on the basis of chromosome numbers within the Annonaceae, suggest that the neotropic regions may be the center for the family. ANNONACEAE 49 evenly divided among the tropics of America, Africa, and Asia. A priori, one might assume (as the present author did before this investigation ) that the Asian-Australasian genera of Myristicaceae are the most primitive in the family. However, it has been learned from Dr. T. K. Wilson, via personal communication, that his preliminary studies on the floral mor- phology of the family seem to indicate that the American genera are more primitive than those of Asia. T hus, it appears that the order Annonales, consisting of the families Annonaceae, Canellaceae, and Myristicaceae, has phytogeographical unity as well as similarities in the floral and pollen morphology. PHYLOGENY INFORMAL INFRAFAMILIAL CLASSIFICATION The following proposed informal classification of the Annonaceae is based primarily upon pollen morphology and to a lesser extent upon floral morphology and phytogeography. Three subfamilies and seven tribes are presently recognized. The hierarchical categories are only informally proposed at this time because it is desirable to defer erecting a formal nomenclature until further morphological studies of the Annonaceae now in progress are complete. The Malmea subfamily contains three tribes: the Malmea, Uvaria, and Guatteria tribes. No tribes are currently recog- nized within the Fusaea subfamily. The Annona subfamily has four tribes: the Hexalobus, Asimina, Annona, and Cymbopetalum tribes (ct., table 10). TABLE 10. PROPOSED INFORMAL CLASSIFICATION OF THE ANNONACEAE I. MALMEA SUBFAMILY . MALMEA Pseudoxandra, Oxandra, Ruizodendron, Unonopsis, Bocageopsis, Onychopeta- lum, Enantia. 2. UVARIA TRIBE: Desmopsis, Stenanona, Reedrollinsia, Sapranthus, Tetrame- ranthus, Duguetia, Polpceratocie iis Cleistopholis, Friesodielsia (African), tem: Popowia ican), Desmos Monanthotaxis, Enneas ’ > Friesodielsia, Uvaria, Anomianthus, Tetrapetalum, Ellipeia, Cyathostemma, Mezzettia, Chieniodendron, Arta , Monocarpia, Cyathocalyx, Drepa- anthus, Mei e, stigma, Guamia, Papualthia, Woodiella, Fissistigma, Mitrella, Melodorum, Alphonsea, Miliusa, Saccopetalum, Phaeanthus, Orophea, Platymi ephora, Pseuduvaria, Popowia, Neouvaria. Guatteria, Guatteriopsis, Heteropetalum. Il. FusaEA SUBFAMILY Anaxagorea, Piptostigma, Neostenanthera, Xylopia, Duckeanthus, Fusaea, Meiocarpidium, Cananga, Goniothalamus, Richella. III. ANNONA SUBFAMILY ]. HEXALOBUS x: Uvariastrum, Uvariopsis, Cleistochlamys, Hexalobus, Mono- D nus. 3. ANNONA TRIBE: Annona, Raimondia, Rollinia, Rolliniopsis. 4. CYMBOPETALUM TRIBE: Cymbopetalum, Cardiopetalum, Porcelia, Trigynaea, Hornschuchia, Disepalum. 50 JAMES W. WALKER TABLE 11. NUMBER OF GENERA AND SPECIES IN THE PROPOSED SUBFAMILIES AND TRIBES OF THE ANNONACEAE Genera Species I. MALMEA SUBFAMILY 64 1570 1. Malmea Tribe i 118 2. Uvaria Tribe 50 1196 3. Guatteria Tribe 5 256 Il. FUSAEA SUBFAMILY 10 310 mI. ANNONA SUBFAMILY 19 oll 1. Hexalobus Tribe 7 68 2, Asimina Tribe 10 3. Annona Tribe 4 198 4. Cymbopetalum Tribe 6 35 Table 11 gives the approximate number of genera and species in each subfamily and tribe, while table 12 is a synoptical, palynological key to the subfamilies and tribes proposed. The Malmea subfamily is characterized by sulcate, inaperturate, or disulculate pollen which is only very rarely in tetrads (Pseudoxandra, Mitrephora, and Pseuduvaria). The columellae are usually medium-sized, although they are so highly reduced as to be indiscernible in the Guatteria tribe. The tectal perforations, when present, also tend to be moderate in size. Florally this subfamily is very diverse, but no septate stamens or syncarps occur in it. The Malmea tribe is composed entirely of genera with sulcate pollen and is without doubt the most primitive tribe palynologically (and also in many aspects of its floral morphology ) within the family. One genus of the Malmea tribe, Pseudoxandra, is the only one in the family to have retained the primitive anasulcate condition. The other genera are presumed to be catasulcate, but this has only been shown for one species, Cremastosperma cauliflorum (Canright, 1963). While Pseudo- xandra is very primitive with regard to its aperture type, its columellae and tectal perforations appear to be somewhat advanced in the direction of the Fusaea subfamily. The basic sculpturing pattern for the tribe (and the family) is considered to be that shown by such genera as Malmea, Cremastosperma, and Unonopsis, with both moderate-sized columellae and tectal perforations. Palynologically, the genera Cremastosperma, Malmea, Ephedranthus, Pseudephedranthus, Unonopsis, Bocageopsis, Monocarpia, and Enantia form a close-knit group with their usually highly reticulate columellae and well-developed tectate-perforate grains. The genera Oxandra, Ruizoden- dron, and Onychopetalum depart from this basic pattern with their tendency toward becoming subsaccate or even strongly perisaccate (Onychopetalum) and their reduced columellae. The latter three genera are also characterized by smaller grain size. The moderately specialized structure and sculpturing of Pseudoxandra, which is combined with a very primitive aperture type, has already been mentioned. Finally, the mono- ANNONACEAE 51 TABLE 12. SYNOPTICAL PALYNOLOGICAL KEY TO THE SUGGESTED SUBFAMILIES AND OF THE ANNONACEAE I. Pollen grains sulcate, inaperturate, or disulculate; mostly solitary, rarely in tetrads; columellae usually medium-sized; tectal perforations, if present, moderate-sized _ . Pee ee i ae Pte na ee Malmea Subfamily. A. Pollen grains sulcate and not echinate ...................--. Malmea Tribe. B. Pollen grains inaperturate, sulcate and echinate, or disulculate, rarely sulcate. 1. Pollen grains inaperturate, sulcate or inaperturate an hinate, or rarely . Uvaria Tribe. 2. Pollen grains disulculate with highly reduced exine and no columellae discern- ible Guatteria Tribe. — lol turate; mostly in tetrads (or polyads), rarely solitary; columellae indiscernible or very large; tectal perforations either very pronounced or highly reduced to pits. A. Columellae very indistinct or indiscernible .............. Fusaea Subfamily. B. Columellae distinct, usually very large ................ Annona Subfamily. 1. Pollen grains in tetrads (rarely solitary ). a. Longest axis of pollen grains rarely more than 70p; mainly African ...... Hexalobus Tribe. . Pollen grains cataulcerate (sometimes sulcate or catasulcate), occasionally inaper- I] b. Longest axis of pollen grains usually more than 80u. (1) Tectal perforations usually pronounce d, from 4-12y; grains never in- d As eC aperturate; United States eit Canes ee imina Tribe. (2) Tectal perforations usually not as pronounced; grains sometimes inaper- turate; tropical America, rarely Africa .............. Annona Tribe 2. Pollen grains in polyads ...............-.---++-- Cymbopetalum Tribe. sulcate grains of Polyceratocarpus with their fragile aperture and small columellae are distinctive. The Malmea tribe is mostly American, with 10 of its 11 genera endemic to the New World. One genus (Enantia) is African. Only three genera in this tribe have more than one ovule per carpel, and they are all among the valvate, not the imbricate-petaled, genera. This would seem to imply that a low ovule number may be primitive for the family and that genera with numerous ovules may have acquired them secondarily. Unonopsis is the only genus in the tribe to have either several ovules or one ovule per carpel, and may show the transition from low to high ovule number. A floral character which is quite prevalent in this tribe is the occurrence of bracts both below and above the articulation in the peduncle. The rounded petals of Cremastosperma and Malmea appear to be primitive for the family and are reminiscent in size, shape, and texture of the petals of Degeneria. The Uvaria tribe is composed mainly of genera with inaperturate pollen but includes a few genera with sulcate and one with disulculate pollen. Palynologically, this tribe is very monotonous with its predominantly inaperturate type of pollen. Two genera have inaperturate grains in tetrads (Mitrephora and Pseuduvaria). Three (Desmos, Dasymaschalon, and Friesodielsia) are quite distinctive with their strongly echinate pollen which may be sulcate or inaperturate. Three genera with predominantly inaperturate pollen (Uvaria, Artabotrys, and Polyalthia) have retained sulcate pollen in a few species, although the sulcus may be reduced and 52 JAMES W. WALKER vestigial. Finally, one genus (Sapranthus) has disulculate pollen along with a rather reduced exine. Uvaria, Anomianthus, Tetrapetalum, and Cyathostemma form a group within the tribe on the basis of their somewhat reduced exine, which often has a wavy appearance. Some of the genera are quite verrucate. A further study of sculpturing types might lead to a better understanding of the interrelationships within this tribe. Duguetia is notable for its highly reduced exine which must be prepared for study by KOH-treatment rather than by the standard acetolysis method. The pollen of Tetrame- ranthus is remarkable for its high degree of psilateness. The pollen of Monanthotaxis, Enneastemon, and the African species of Popowia is distinctive with its microbaculate sculpturing. Phytogeographically, the Uvaria tribe is predominantly Asian, with only six American genera out of a total of 50. The tribe is florally diverse, although no syncarps occur among its genera. Mention should be made of the occurrence of clawed, mitriform petals in one group of evidently closely related genera (Orophea, M itrephora, Pseuduvaria, etc.). The author intends to divide this large tribe into subtribes in a subsequent paper. However, to do so now, with further studies on the Annonaceae in progress, would be premature. The third tribe of the Malmea subfamily is the Guatteria tribe with only three genera, but some 250 species. Its pollen is highly distinctive, being disulculate and with a strongly reduced exine. All members of this tribe have bracts below the articulation in the peduncle and none above, and all have a solitary, basal ovule. They are entirely New World. The Fusaea subfamily, which is characterized by cataulcerate pollen usually in tetrads (or polyads), has the columellae reduced so as to be indiscernible. The trend toward pollen gigantism is evident. The anthers are septate in a number of genera and the pollen is solitary in only two (Anaxagorea and Piptostigma). The fruit type of Anaxagorea is unique in the family in being a dehis- cent follicle with two seeds. Again, this low seed number is taken as a primitive character and the dry, dehiscent fruit is considered to represent a primitive type within the family, reminiscent of the Magnoliaceae. The genus Anaxagorea is also remarkable for its primitive, laminar, non-peltate stamens, which are without doubt the most primitive stamens extant within the family. The pollen of Xylopia (as well as its fruit type—a dehis- cent berry) is somewhat intermediate between that of Anaxagorea and the rest of the subfamily. Phytogeographically, this subfamily is repre- sented in all three world centers of distribution. Its antiquity may be seen in the unique, bicentric distribution of Anaxagorea (America and Asia) and in the unique, tricentric distribution of Xylopia (America, Africa, and Asia). The Annona subfamily has four tribes. The pollen is predominantly cataulcerate or rarely secondarily inaperturate. It is remarkable for its large to gigantic columellae as well as for very prominent tectal perfora- ANNONACEAE 53 tions. The grains are mostly in tetrads or polyads. There is a very strong trend toward pollen gigantism, as well as toward septate stamens. The subfamily is almost entirely American with the notable exception of the first and presumably most primitive tribe (the Hexalobus tribe), which is centered in Africa. The Hexalobus tribe exhibits all the initial trends so common in this subfamily as a whole. It, along with the majority of the genera of two of the other tribes (the Asimina and Cymbopetalum tribes), has numerous ovules in most of its species. Only the Annona tribe itself is character- ized by a single ovule in each carpel. Thus, numerous ovules appear to be basic in this subfamily, in contrast to the other two. Monodora and Isolona are the only genera in the family with a uniloc- ular, compound pistil with parietal-laminar placentation. This may repre- sent (along with the Canellaceae) one of the few instances in the angiosperms of primary parietal placentation as opposed to parietal placentation secondarily derived from axile placentation. The Asimina tribe is composed of two small genera, Asimina and Deeringothamnus, both entirely North American. Their pollen grains are somewhat larger than those in the preceding tribe. They have much larger columellae and are much more evidently tectate-perforate. The mem- branous petals that are often wrinkled are reminiscent of those of Hexalobus and its allies. The Annona tribe retains pollen in its more primitive members (Annona sect. Annona) which is quite similar to that of Asimina. However, this tribe is characterized by syncarpous fruits and large, thick, fleshy petals, which are highly reminiscent of Porcelia and C ymbopetalum in the next tribe. Solitary, inaperturate pollen characterizes the more advanced sections of Annona, as well as the closely related genera Rollinia and Rolliniopsis. The tribe is entirely American except for a few African species of Annona. The last tribe, the Cymbopetalum tribe, is characterized by polyads and septate stamens (except in Disepalum). The fruits of the more prim- itive members are highly reminiscent of those of Asimina, while the petals show similarity, as mentioned before, with Annona. The fruit of Cymbo- petalum is distinctive in that it opens laterally. An almost constant feature in this tribe is the totally ebracteate peduncle of the flowers. Arillate seeds are also of frequent occurrence. In connection with the septate stamens found in Cymbopetalum and its allies, it is interesting to note that Herms (1907), Samuelsson (1914), and Lecomte (1896) found what may be interpreted as rudimentary septa, which break down by the time the pollen tetrads are mature, in the developing stamens of Asimina, Annona, and Monodora respectively. Disepalum is somewhat separated from the other members of this tribe with its non-septate anthers (at least at maturity) and solitary ovule. The tribe is entirely American with the exception of Disepalum, which is Asian. 54 JAMES W. WALKER Previous INFRAFAMILIAL CLASSIFICATION There are two modern, world-wide treatments of the Annonaceae: Fries, 1959; and Hutchinson, 1964. Sinclair’s revision of 1955 covers only the Malayan members of the family. Other papers important for the clas- sification of the family include Diels (1932) and Fries (1942). Table 13 gives a summary of the subfamilial and tribal treatments of the family by Fries, Hutchinson, and Sinclair. They all agree in recognizing two sub- families, the Annonoideae and the Monodoroideae, which has only two genera, Monodora and Isolona. They also recognize two major tribes, the Uvarieae and the Unoneae, which are distinguished solely on the char- acter of imbricate versus valvate aestivation of the petals. The only major difference among the three systems is the recognition by Hutchinson and Sinclair of a tribe Miliuseae and its rejection by Fries, with the statement that it is a very unnatural tribe, being based upon the single character of reduced, sepaloid, outer petals. The systems of Sinclair and Hutchinson are very artificial, as Hutchin- son himself admits, and are largely patterned after the classification of Bentham and Hooker. Hutchinson’s Miliuseae is an extremely unnatural taxon, basically containing not only a number of genera with inaperturate pollen of the Uvaria tribe, but also Heteropetalum of the Guatteria tribe, Piptostigma of the Fusaea subfamily, and Cymbopetalum of the Annona subfamily. Thus Hutchinson, by using a single floral character, has com- bined genera with inaperturate, disulculate, sulcate, and cataulcerate- TABLE 13. SUMMARY OF SOME FORMER INFRAFAMILIAL CLASSIFICATIONS OF THE ANNONACEAE Fries (1959) Hutchinson (1964) Sinclair (1955) Annonoideae Annonoideae Annonoideae Uvarieae Uvarieae i Miliuseae Miliuseae — ee Unoneae Unoneae Asimina Group Xylopiinae Xylopieae Henalobus Group Group A Mitrephoreae ase Group Group B Annoneae Unonea Group C Monodoroideae a Grou Annoninae Polyalthia Group Monodoroideae Unonopsis Group Xylopia Group Artabo Group Orophea Group Annona re Trigynaea i ap Group Tetramerantheae Monodoroideae polyad pollen all in the same tribe. By contrast Fries, in his system, correctly placed Piptostigma next to Anaxagorea, Heteropetalum next to Guatteria, and Cymbopetalum in the same group with the other polyad ANNONACEAE 55 genera with septate stamens. We may dispense with further considera- tion of Hutchinson’s system and turn to the only modern, world-wide classification of the Annonaceae which is partially natural, that of Fries. Although Fries relied predominantly upon floral morphology, it is evident that his life-long experience with the family led him to select characters which, on the whole, are more useful in erecting a natural classification of the family than those used by Hutchinson. Fries proposes 14 “groups” which are comparable to tribes. The greatest weakness of his system is that he still recognizes a primary division based on petal aestiva- tion. Characters that he uses which often lead to the recognition of natural groups include: the location of bracts on the peduncle, the type and posi- tion of the inflorescence, the number of ovules per carpel, and the occur- rence of septate stamens. The naturalness of a number of Fries’ “groups” has been confirmed by their pollen morphology. This is especially true of his Uvaria, Guatteria, Annona, and Trigynaea groups. However, his use of a single floral character often led to the separation of closely related gen- era, e.g., Malmea and Cremastosperma; Desmos, Dasymaschalon, and Friesodielsia. Many of the tribes proposed in this study have their nucleus in one or more of Fries’ “groups.” The only infrafamilial taxon which is here proposed that has been totally unrecognized by all previous workers is the Fusaea subfamily. Its members, however, appear to have such distinc- tive and similar pollen in almost all characters as to strongly support the naturalness of the group. Monodora and Isolona, although isolated with reference to their unilocular, compound pistil, seem better placed, on the totality of their floral and palynological characters, as members of the Hexalobus tribe rather than in a separate subfamily of their own. Table 14 lists the segregate genera of the Annonaceae and indicates their placement in the systems of Fries, Hutchinson, and Sinclair. Airy- Shaw’s treatment in the newest edition of Willis’ Dictionary (1966) is also recorded. Among the New World genera, there is only one (Geanthemum) which is in dispute, Both Fries and Airy-Shaw submerge it into Duguetia, while Hutchinson recognizes it as a separate genus. The pollen is that of a typical member of the genus Duguetia and does not support the mainte- nance of Geanthemum as a separate genus. Mention should also be made that pollen morphology supports the separation of the genus Deeringo- thamnus from Asimina. Palynological data which are relevant to other generic problems include the following: 1) Support the inclusion of Brieya in Piptostigma. 2) Do not support the inclusion of M onocarpia in Cyathocalyx. 3) Support the inclusion of Saccopetalum in Miliusa. 4) Support the close proximity of Mitrella to Fissistigma. 5) Support the inclusion of Dasymaschalon in Desmos. 6) Support the inclusion of Drepananthus in Cyathocalyx. 56 JAMES W. WALKER 7) Definitely do not support the inclusion by both Fries and Hutchin- son of Friesodielsia (as Oxymitra) in Richella.* COMMENTS ON THE CLASSIFICATION OF CERTAIN GENERA Nor INCLUDED IN Tuts STUDY Some 39 genera of Annonaceae were not included in the present study because of a lack of palynological material. Together they contain only about 70 species, but the African ones especially may be very important in adding to our knowledge of the family. On the basis of floral descrip- tions and some palynological data in the literature, I would like to comment on or predict the following concerning the classification of certain of these genera: 1) that Guatteriella should have disulculate pollen with an extremely reduced exine if it is correctly placed by Fries next to Guatteria. 2) that Bocagea should have polyads and cataulcerate pollen with large columellae and large, tectal perforations if it is correctly placed by Fries near Cymbopetalum. 3) that Froesiodendron will have polyads and cataulcerate pollen with large columellae and large, tectal perforations since its septate stamens and other characters appear to indicate its proper assignment to the Cymbopetalum tribe. 4) that Afroguatteria should have inaperturate pollen with distinct columellae if Fries’ placement of it in his “Uvaria group” is correct, or disulculate pollen with a highly reduced exine if Hutchinson is correct in submerging the genus into Guatteria. 5) that Uvariodendron will have cataulcerate pollen with large columel- lae and a tectate-perforate exine based on Fries’ statement that the grains are in tetrads and based on its floral morphology and distribution, which all indicate its placement in the Hexalobus tribe. 6) that Xylopiastrum should have cataulcerate grains in tetrads or polyads with indiscernible columellae if it is closely related to Xylopia, or solitary, inaperturate grains if related to Uvaria. 7) that Anonidium will have cataulcerate tetrads with large columellae since it appears to be closely related to Annona. PoLLEN MORPHOLOGY AND INTERFAMILIAL RELATIONSHIPS A number of pollen characters found within the Annonaceae appear to indicate relationships with the pollen types of certain other “ranalean” 15This poses a nomenclatural problem in that Oxrymitra is a later homonym of a hepatic — There was no problem if one considered the genus congeneric with Richella. This cannot be done, a ei however, since the pollen clearly indicates that there is not ev relati p libs the wo er name, Friesodielsia, 0. Oxymitra by van Steenis (1948), d the necessary new ie were made by him in 1964. It was unfortunate that Fries (1959) made a number of new combinations with Richella, which waist now be abandoned in light of the palynological postin TABLE 14, DIFFERING TREATMENTS OF CERTAIN GENERA OF THE ANNONACEAE” Vv aAVaAOVNON Genus Fries (1959) Hutchinson (1964) Sinclair (1955) Airy-Shaw (1966) American Geanthemum Duguetia + _ Duguetia ic oguatteria + Guatteria = + Cleistochlamys +. Popowia _ Xylopias + Xylopia = Uvaria Brieya Piptostigma +- — Tetrastemma Uvariopsis + _ Uvariopsis Thonne Uvariopsis + - Uvariopsis Asian Fitzalania + Uvaria — + Monocarpia + Cyathocalyx + Sphaerocoryne Polyalthia Melodorum Lour. soon Lour. Marcuccia Enicosanthum + Enicosanthum Enicosan Sphaerothalamus Polyalthia + _ Polyalthi: Griffithian Enicosanthum + Enicosanthum Enicosanthum accopetal liusa Miliusa sa Pyramidanthe Fissistigma Fissistigma Ha Fissistigma Fissistigma + Ararocarpus Meiogyne virgata Meiogyn D aschalon + + + (—Desmos ) Drepananthus + + Cyathocalyx Cyathocalyx Melodorum Lour. Doubtful genus — ao =Polyalthia sp. +Mitrephora sp. Friesodielsia Richella Richella + + (as Oxymitra ) + Accepted as a genus. — Not treated. * The listing of the generic names indicates those in which the various segregate genera are submerged by different authors. For example, the genus Geanthemum is cre gl as a . nus by Hutchinson, it is submerged into Duguetia by both my and Airy-Shaw, 4 is not treated by Sinclair. topostema is included in Sabai via by Le Thomas in the Flore du Gabon, No. 16 (19 Ahn genera listed by Fries (1959): ‘Polecue ie Griff., Pelticalyx Griff, Soala Blakes: and Th Norunha. 58 JAMES W. WALKER families. Within what may be called the Magnoliad line of primitive, “rana- lean” families, four separate orders may be erected containing the follow- ing families: MAGNOLIALES: Magnoliaceae, Degeneriaceae, Himantandraceae, Eupomatiaceae. i ANNONALEsS: Annonaceae, Canellaceae, Myristicaceae. ARISTOLOCHIALES: Aristolochia- URALEs: Austrobaileyaceae, Trimeniaceae, Calycanthaceae, Amborellaceae, diaceae. Monimiaceae, Gomortegaceae, Lauraceae, Hernandia The pollen of Pseudoxandra, especially of P. coriacea with its anasulcate and anatrichotomosulcate grains and somewhat reduced columellae, resembles the pollen found in the Canellaceae (and to some degree that of the Magnoliaceae ). This type of pollen in the two families (Canellaceae and Annonaceae) may represent directly homologous pollen grains. The resemblance of other pollen types in the Annonaceae to the pollen of related “ranalean” families may be indicative of a phylogenetic relation- ship, but probably only through parallel evolution. The pollen of certain genera of Myristicaceae shows some similarity with the pollen of the Annona subfamily with respect to the presence of large, prominent columellae. In this connection it would be of some inter- est to determine the exact position of the aperture in myristicaceous grains of this type. Other myristicaceous grains and some in the Aristo- lochiaceae resemble Desmos and its allies in their echinate sculpturing. The somewhat reduced monosulcate grains of Anaxagorea, with no discernible columellae, resemble in many respects the pollen of the Himantandraceae and to a lesser extent that of the Degeneriaceae, and may be the result of parallel evolution. The development of numerous inaperturate pollen types within the Annonaceae probably reflects a common potential with the lauralean families, and is a trait that became fixed in the majority of the members of the latter group. Finally, the discovery of disulculate grains within the family has an important bearing upon the relationship of the Annonaceae with the Eupomatiaceae. The disulculate pollen found in the Eupomatiaceae, with its reduced exine, more closely resembles that of Guatteria and its allied genera in the Annonaceae than it resembles Calycanthus in the Laurales. The occurrence of this pollen type in both families would appear to be another character that supports the relationship of Eupomatia with the Annonaceae rather than with the Calycanthaceae, especially since both families possess ruminate endosperm. The discovery of a number of disulculate genera within the Annonaceae negates the position taken by Canright (1963) relative to the relationships of the Eupomatiaceae. SUMMARY A detailed description of the range of pollen morphology within the family nnonaceae has been presented, in addition toa scmmaar : classification of the family, which hopefully represents the most natural system to date. The main results of this y may be summed up as follows: 1) Morphological. For the first time a comprehensive study, with detailed, generic descriptions, has been undertaken on the pollen of the Annonaceae. ANNONACEAE 59 2) Taxonomic. A number of obviously misplaced species were discovered in the course of this study, e.g., two species of Polyalthia which belong in the genus Sa eta sa of Orophea which are probably species of Pseuduvaria, etc. 3) netic. The family Annonaceae is eurypalynous enough to allow a com- plete reclassification at the subfamilial and tribal levels, based primarily on pollen morpho 4) Evolutionary. The present study revealed a number of eaciggite. evolutionary trends within the pollen of the family, at: suggestions have been made concerning the selective value of many of these tren 5) Phytogeographical. The study has eae the rather surprising fact that there is very strong evidence, from both floral a ~ Bsns morphology, for the New World and/or possibly praia origin of the Annona n the course of the pollen survey a number of interesting discoveries were made. The. most important of these include the following: 1) Disulculate apertures were found in a number of genera for the first time in the family. This has significance for the relationship between the Annonaceae and the pierre mber of genera were found to have an extremely reduced exine, quite vonethibie for large, non-aquatic, tropical trees. 3) A natural group of genera was Agee which is characterized without excep- tion by the pollen grains being in polya 4) Probably the largest known ‘cl pollen grain in the angiosperms was dis- covered in Cymbopetalum odoratissimum, some grains of which reach 350,. 5) Primitive, laminar, leaf-like, stomate-possessing stamens were found in the genus Anaxagore: a. These are the only stamens in the family to show remains of the lateral vascular tr 6) The Fusaea subfamily was first recognized because of a remarkably distinct pollen type common to a number of genera previously widely separated in classifica- tion systems. 7) An extremely interesting and probably unique trend was discover ed in the tetrad and polyad genera, in w which the entire proximal face of the pollen grain. is ultimately lacking in exine, with the intine from different grains centrally contiguous m). 8) The primitive pollen type for the family (anasulcate) was discovered in the genus Pseudoxandra and the complete transition from anasulcate to catasulcate was observe: os —_— g the species of this genus us. The sulcus in other other of Annonaceae known “ranalean” ACKNO The author wishes to thank Dr. Reed ¢ C. > Rollins, 4 Asa Gray Professor of Systematic Botany and Director of the Gray Herbarium of Harvard University, for his counsel as thesis advisor rere e course of this study. Both his help and friendship are sincerel er asians @ oh" ave been very helpful -ecdireae ad period a the Department of Biology, coos University. I am Rolla M. Tryon, Carroll E. Wood, Jr., and Lorin I. Nena i or help and advice. would like to express m ain to Professor Elso S. Bar of equipment and sain facilites in the Paleobotanical Laboratory. My deep appreciation goes t gsc Dr. and Mrs. Elso S. Barghoorn for help with the photo- phic aspects of the — My very special nieny go to Dr. James A. Doyle for many hours of stimulating discussion on various aspects of this study and for his help with the photomicroscopy. 60 JAMES W. WALKER I am indebted to Jeolco, Inc., Medford, Massachusetts, for use of their JSM-2 scanning electron microscope. upport is gratefully acknowledged from the Evolutionary Biology Committee of the Department of Biology, Harvard University, for financial Me for field work derived from N ants G 19727, GB 3167, and GB 7346 (Reed C. Rollins, Principal Investigator ). Acknowledgement for financial support for field work is also given to Fe rnald ] Fund of Harvard University and to the Organization for Tropical Studies. versity; Arnold Arboretum, Harvard University; New York Botanical Garden; United States National Herbarium, Washington, D.C.; and the Field Museum of Natural History, Chicago, Illinois. fe Others who gave help and assistance in the course of field fades include: DE Leslie R. Holdridge, San Jose, Costa Rica; Dr. Jesus M. Idrobo, Universidad Nacional, ona Colombia; and Mr. George R. Proctor, Institute of Jamaica, Kingston, Jamaic LITERATURE CITED AGABABYAN, V. Su. 1967. 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Berg. 10:199-341, ANNONACEAE 61 a 1934. Revision der Arten einiger Anonaceen-Gattungen, III. Acta Hort. Berg. 12: Thee ee 937. Revision der Arten einiger Annonaceen- -Gattungen. IV. Acta Hort. Berg. 12: 221-288. Par Roi 9. Revision der Arten einiger Annonaceen-Gattungen. V. Acta Hort. Berg. 12: 289-577. ——————~— 1942. (Actual date of publication, 1943.) Einige Gesichtspunkte zur systematischen le rung der amerikanischen Annonaceen-Gattungen. Arkiv Bot. 30A ae: —_—————— ny erate in Die natiirlichen Pflanzenfamilien, ed. 2, 17all. Duncher i Humblot, Berlin Grant, V. 1950. The protection - ovules in flowering plants. Evol. 4:179-201. Hers, W. B. 1907. Contributions to the life history of Asimina triloba. Ohio Nat. 8:211-217 sate J. 1964. The Genera of Flowering Plants. Vol. 1. Oxford University Pre don. Kormanova L. A. 1967. Pgh gan of pollen grains and their evolution in angiosperms. v. Palaeobotan. Palynol. 3:73-80. Lecones H. 1896. Sur la formation du pollen chez les Anonacées, Bull. Mus. Hist. — 1896: 152— LE Ress E. eae 1876. A General System of Botany (trans. by Mrs. Hooker). Leenaed Green & Co., London (original French edition, 1868 ). Le Tuomas, A. 1969. Jeannie in Flore du Gabon, No. 16. Muséum National "Histoire Naturelle, P Locke, J. F. 1936. Kiser peso and cytokinesis in Asimina triloba. Bot. Gaz. 98: 159-168. MAHEsHwankI, P. 1950. An a to the Embryology of Angiosperms. McGraw- Hill Book Co., Inc., New MigQuEL, F. A. G. 1856. Eenacee in ; hcaiut Flora oo vol. 7. (For descrip- tion of Hornschuchia see Pp. 8-19, plate 7, fig. 12.) Mont, H. von. 1834. Beitriige zur Anatomie und Physiologie der sir I. Uber den Bau und die Formen ‘dee oe Pollen kent: Chr. Fischer un MvuELLER, F. 1865-66. ape eae Phytographiae agree ior 5. ioe PeriasaMy, K. « B. G. L. S . 1959. Studies in the ceae I. Microsporo- genesis in Cananga zeal ng Miliusa wightiana. oh apne abey 9:251-263. Sauer G, 1914. Uber die Pollenentwicklung von Anona und Aristolochia und ihre tische Bedeutung. Svensk. Bot. Tidskr. 8:181-189. Smee J. 1955. A revision of the Malayan Annonaceae. Gard. Bull. Singapore a A. C. 1967. The presence of primitive angiosperms in the Amazon signific ance in ficlientiag migrational routes. Atas do Simpésio ae a Biota parent; vol. 4 ( Botanica) :37-59. Sorsa, P. 1969. Pollen morphological studies on the Mimosaceae. Ann. Bot. Fenn. 6:1-34. SreEnts, C. G. G. J. vAN. 1948. (Actual date of a 1949.) Remarks on some generic names used for Malaysian phanerogams. I. Bull. Bot. Gard. Buitenz. series 3. 17: Sere ——_—————. 1964. An account of the age Richella A. Gray and Oxymitra (BI.) Hook £. & Th. fanscnsenie) Blumea 53-361 VANDER Wyk, R. W. 1950. The grant gee of the Annonaceae. (In part, unpublished Soo eg Harvard University, Cambridge, Mass. gine 1956. The anatomy and relationships of the Annonaceae. 134. «J.E ee Woods 1 : Verpcourt, B. 1969. aks agew ag the genus Polyalthia Blume (Annonaceae) in Africa. Adansonia, ser. 2, 9:87-94. 62 JAMES W. WALKER Wurreueap, D. R. 1969. Wind upalbratien in the angiosperms: evolutionary and envi- ronmental considerations. Evol. 23:28—35 Wru:son, T. K. 1964. Comparative morphology at the Canellaceae. III. Pollen. Bot. Gaz. 92-197. Wopenovse, R. P. 1935. Pollen Grains. McGraw-Hill Book Co. (Facsimile of the 1935 edition published by Hafner Publishing Co., New York, 1965. ) ANNONACEAE . Unonopsis venefici- F E 1. Fic. 1. Malmea rears nsis R. E. Fries, X 200. Fic. orum alee ~ Be ies, 200. Fic. 3-5. Pseudoxandra coriacea R. E. Fries; vee $8. eT oees in 5) Xx 1000. “Fie. 6. Dasymaschalon glaucum Merr. & Chu « 1000 JAMES W. WALKER ew TE 2. Fie. 1- Ps Malmea raimondii (Diels) R. E. Fries; Fig. 1, * 500; Fig. 2-4, 1000. Fic ig sige get sdandiae * (Diels) R. EX Fries, 500. Fic.. 6. F- wit (R. gore R. E: Fries, X 500. Fic. 7. Malmea obovata R. E. Fries, 500. Fig. 8-12. M. pistes R. E. Fries; Fig. 8, X 500; Fig. 9-12, K 1000. ries; Fig. 8, 9, 500. Fic. 11. O. ia R. E. Fries, X 500 a E. Fries, X Se : Arist . x ANNONACEAE ATE 3. Fic. 1-3. Cremastos pert longicuspe R. E. 1000. Tay Ys - cauhflorun E. Fries, xX mr 8 GPE R. E. Fries, X 500. Fie. 8,9. 1000. Fic. 10. Oxand 242. O auntala fee ) & Rich., oe Pant nde ose e pt Ha %% Lhe os & » dF a £4 5 2% * Fries; Fig. 50) Fig 500. Fie. 5. : ‘mepalop hilum 500. Ephedranthas auienensis Ee. krukoffit Fries JAMES W. WALKER ATE 4. Fic. 1,4. Onychopetalum krukoffa R. E. Fries; Fig. 1, * 1000; Fig. 4, X i i 000; 0 500. Fic. 2,3,5. O. lucidum R. E. Fries; Fig. 2,3, < 1000; Fig. 5, * 500. Fic. 6. Bocageopsis multiflora (Mart.) R. E. Fries, X 500. Fic. 7. Ruizodendron ovale (Ruiz & Pav.) R. E. Fries, * 1000. ct ANNONACEAE a Heo ig 8? RE. Pa x U. grandis . Fic onocarpia LOOSE SE (cha vy ea 500. io i] | ct sae a fad ts 7 bry a oO a Fic. 4,5. Enantia icine Engl. % tote Fig. 4, X 500; Fig. 5, X 1000. Fic. ~ Polyceratocarpus sebeeegiseo (Bak.f.) Ghesq.; Fig. 6, 500; Fig. 7, X 1000. sige a Desmos cochinchinensts x 500. Fic. 9. D. onal oa & Th.) Saff. 500. Fic. 10. D. dunalit sis ex ik £. & Th.) Saff., X 500. Rae & a) 5 zeslanicns ik ® Th.) Saff., X 500. Fie. 12. Da symaschalon erect bes Merr., X 68 JAMES W. WALKER e 6. Fic. 1-3. sien esr sootepense Craib, Fic. 4. De gee PLa dumorn (Roxb.) Saff., X 1000. Fic. 5. Mo x nanthotaxis poggei ie & Diels, < 10 . Enneastemon mannii (Baill.) Keay, < 1000 ANNONACEAE . Fic. 1. Dasymaschalon glauc um Merr. & x 500. Fic. 2,3. oe z i sodielsia Se ri ls) van Steenis, X 500. 1c. 5. F. bakeri (Merr.) van Steenis, 500. Fic. 6. Enneastemon foliosus (Engl. & Diels) Robyns & Ghesq., X 1000. Fic. 7. Stenanona panamensis Standl., X 500. Fie. 8. a 8 is) 7 % ' G A) 2) ca] ty =] a uw neg a. bed S. costaricensis R. E. Fries, . 1000. Fic. 9. Reedrollinsia Walker, X 500. Fic. 10. igegeod oS am on) Sa x 500. Fic. 11. Tetram mg _—e . E. Fries, 500. Fie. 12. Daowelia ‘stelechantha (Diels) R. E. 500. 70 ATE 8. Fic (Rohn) Saff., JAMES W. WALKER 1-3. Co mee : 1000. 7 4,5. Desmopsis panamensis Fig. x 200 a ay 1000. 6. Uvaria javana Dunal, ANNONACEAE Piate 9. Fic. 1. Uvaria bipindensis Engl., X 500. Fic. . purpurea Bl. 1000 1G. 3. gba dulcis (Dunal Sincl., X 500. Fie. ic gel ncthlderen Lae 500. Fr ipeia cuneifolia ae Sha oi Fic. 6. Cyathostemma excelsum (Hk.f. & ) J. Sincl., Fic. cosanthum grandifolium (El - we. Fig. 7, 0 Fig. 8 G. . Clestophot fatens enth.) Engl. & Di 0. Fic. 10. Sageraea papers Hk. x I 1 oe ae ay ie 0 cer burahe!l (BI. ) Hk.f. & Th., . Fic JAMES W. WALKER PLaTE 10. Fic. 1. Sageraea lanceolata Miq., < 1000. ei - a a 3. Polyalthia hookeriana King, < 200. Boerl., 000. rungs enhoffia siamensis . 4-6. ®. glauca (Hassk.) PuaTE 11. Fic leichhardtit Fic. 4,5 hypoleuca Hk 5 Aug. c, x 500. Fic. 9. C. umbellata Becc., 12, x 1000 hieniodendron hainontnse 500 ANNONACEAE a ue FRI eS ap g A aD ey 1G. e Tsiang . Ea, 11,12. Woodiella Aste os Fig. 11 12 500; 74 JAMES W. WALKER 1 10 TE 12. Fic. 1,2. Neouvaria acuminatissima (Miq.) oe Shaw; Fig. 1, xX. 500; Fig a ht Fre. 4: Te te reticulata (Elm.) <9 “ oe 4,5, Miliusa Shwe = Wang; Fig. 4 500; Fig. 5, «x 1000 ov ve a Hk.f. & Th., «x 500. G. av M. comtonalata fens as 1G. a" Saccpetlam tomentosum Fic. 500. Fic ne Hk.f. & sg 500. F stigma acuminatissimm Mer Mitrella kenti pene Migq., ‘x 500. 1 it; lodorum aberrans sce ex Hk. Th J. Suck, X $00: Fie. 12: Poise pets monosperma (Hk.f. & Th.) J. sack, ANNONACEAE 1000. Fie. 2. sh gsc reticulata velutina Hk.f. & Th., X 10 0. . M. 1 tabotrys euiduass (Lam.) Merr., “ig “1000 . Fre. 6. Puate 13. Fic. 1. Polyalthia cheliensis -~ ge . 3. Milius (Elm.) Merr., X get panulata Pierre, Fre - seo Mitrephora itl ae ~I Ol JAMES W. WALKER 10 PLaTE 14, Fig. 1,2 amia mariannae 2 : Pie 1X ; Fig. 2, .<- 1000. Fic. 3. Avtabetrse cheats ag x 500. . 4-6. A, pala (BL) BI1.; Fig. 4, x 500; Fig. 5,6, x wy anasop Engl., X 500. Fic. 8. A. uncinatus a (Lam.) Merr., x i via . par ets papuanus Diels, * 500. Fic. 10. C. insularis A. C. Smith, 0. Fic. 11. Drepananthus philippinensis Merr., <> 500. Fie. 12 Orophea leytensis Merr., * 500. ANNONACEAE Late 15. Fic. 1. Orophea vulcanica Elm., X 500. Fic. 2. Platymitra macrocarpa Boerl., 500. Fic. 3. Pseuduvaria philippinensis Merr., 500. Fic. 4. P. versteegit (Diels) Mer x 500. Fic. 5. P. reticulata (Bl.) Migq., X 500. Fre ig ge a (Bi.) Merr., X 500. Fic. 7. Orophea lugonensis Merr., X 500. Fic. 8-10. Nopiaia tire rantha sh Baill.) Diels; Fig. 8, X 500; Fig. 9,10, X 1000. Fie. 11,12. P. gracilis Oliv. ex Engl. & Diels; Fig. 11, X 500; Fig. 12, X 1000. TE Fic o < 500. reticulata (BL) Mia., x 1000. Fic. 3,4. P. 0 Bl. err., luzonensis Merr., > JAMES W. WALKER 1. Mitrephora williamsii fe B. S ) N 1000. Fic. 6. Pe i crassipetalus Becc., Fic. wage 2. Pseuduvaria Fic. 5. Orophe 000. ANNONACEAE PrartE 17. . Popowia soca a sot Fig. 1, X 500; Fig. 2, Fic FIG. op 000. ia 3: ‘Phae ean ere earn eaite talus Becc., 0. . P. ebracteolatus sak: Sag a ae Trivalvaria macrophylla a Mia., x 500. Fie. 6. Sapranthus ering z 7 ris, pores Fic. 7. S. sp.» X 1G. 8. Guatteria Se Donn. Smith, os Guatteriopsis sessilifora (Benth.) R: E. Fr 500. Fic 12 Paonia brasiliense Benth., 79 JAMES W. WALKER TE 18. Fic. 1. Sapranthus palanga R. % rig * 1000. Fic. 2-4. S. sp., 1000. Pra Fic. 5,6. Guatteria oliviformis Donn. Smith, ANNONACEAE 19. Fic. 1. Anaxagorea —. Benth. in Hk.f., X 500. Fre. 2,3. A. dolicho- — Sprague & Pi dw., X 500. Fic. 4. A. anal (Dun.) St. Hil, ex A. DC. X 500. . 5-8. A. comeiconsls Ko S. ibe Fig. 5,7, X 500; Fig. 6,8, x 1000. JAMES W. WALKER Pirate 20. Fic. 1,2. Anaxagorea costaricensis R. E. Pries:' Fig. 1, <° 100: Fic. 2, x 200. ANNONACEAE Piate 21. Fic. 1,2. Anaxagorea costaricensis R. E. Fries, > 4 100. 3 JAMES W. WALKER Fic. 1. oo multinervium Engl. & Diels, x 500. Fic. 2,3. pia densiflora R. E. Fries, & 500. Fic. 5. RoE: 7 PLA og olabrescens Oliv., X 500. Fic. 4. Xylopi ast Hil; x o -) deviled: (Engl. & Diels) Exell; Fig. 1, X 500; Fig. 12, x 1 ANNONACEAE 2-4. X. sericea 5. X. polyantha R. E. Fries, Pirate 23. Fie. 1. Fag wied africana oe Oliv., X 500. Fic. St. Hil.; Fig. 2,4, < 1000; Fig. Fic. x 200. Fic. 6. X. brasiliensis Spreng. x a 85 86 JAMES W. WALKER Puate 24. Fic. 1,2. _— densiflora R. E. Fries, X 0 Fic. 3. X. aromatica Bye: a x 200. Fic. 4,5. X. polyantha R. E. Fries, X 1 ANNONACEAE E 25. Fic. 1. Xylopia ferruginea wpe & Th) Hit & Th, xX 200. Fre. 2. ae mers (L.f.) Sprague & Hutchinson, K 2 88 JAMES W. WALKER PLATE 26. Fic. 1. en gag (Aubl orondiforn R. E. Fries, < 200. 34: Co 0: Fig. 4.°% rape. Fic, 5, ‘ c latifolia (Hk.f. & Th.) Finet & Gagnep.; Fig. 5, x a Fig. 6, X 200 .) Saff., X 500. Fic. 2. Duckeanthus nanga odorata (Lam.) Hk.f. & Th.; Fig. ANNONACEAE Pirate 27. Fic. 1. Fusaea decurrens R. E. Fries, X 500. Fie. 2. Duckeanthus en florus R. E. Frie - 1000. Fic. 3. Cananga odorata (Lam.) Hk.f. & Th., X 200. 4-6. C. latifolia (Hk. £.& Th. ) Finet & Gagnep., X 1000. JAMES W. WALKER Pate 28. Fic. 1. Meiocarpidium lepidotum (Oliv.) Engl. & Diels, x 500. Fic. Goniathelama pr ese Mere: 06 200) Figs? 3.0 pobnditiovas (Warb.) a 500. Fic. 4. G. chartaceus Li, X< 1000. Fic. 5. G. curttsii King, a 6. Mahidove junodii Engl. & Diels, X 500. ANNONACEAE Neostenanthera ees (Oliv.) Exell, xX 500. Fi 00. Prate 29. Fie. :t. a ai Sa saigonensis Pierre ex 00 4. G. , FIG. A. Gray, X 500. Fic. 6. Isolona congolana (De Wild. & Th. Dur. ngl. & Diels, X Fic. 7. I. pilosa Diels, 500. Fic. 8. I. ger apagt Engl. & Diels, X 500. Fic. 9. Fic P Uvariastrum pierreanum Engl., X 500. U. zenkeri Engl. & Diels, X 1000. King, x, 3ray, Fic. A simina etteba (L. ) Dunal, x G. 5 JAMES W. WALKER Priate 30. Fie. 1. bs tt nana velutinus ele se 200. Fic unctic ee x 200. Fic. 2. G. curtis er Fic. 4. ‘Richelle monosperma Diclinanona Selecta ote R. E. Fries, * 500; Fig. 6, x 1000. 5; ANNONACEAE Mais ee?) sho 35. S35 a”. ee & . be PSPS ittieri f 43. Fic. 1. Annona practermissa Fawc. & Rendle, X 500. Fic. 2,3. A. p 2 200; Fig. 3, X 1000. Fie. 4,5. A. macroprophyllata Donn. mith; Fig i G. 6. if Rich., xX 1000. Fic. 7. A. crassivenia Saff., 1000. Fic. 8. A. haitiensis R. E. Fries, x 1000. Fic. 9. A. rosei Sa x 1000. Fic. 10. A. dumetorum R. E. Fries, X 1000. Fic. 11. A. bicolor Urb., X 1000. Fie. 12. A. globiflora Schlecht., X 1000. 106 JAMES W. WALKER PiatE 44. Fic. . Rollinia emarginata ree a doe AG a ' Fig. 2, x 1000. sy : _ intermedi og E. Fries, ene wo rigidiflor . E. Fries, X 500. . Fries, < 500... Fie. i " microsepala oe x 500. Fic. 7. Reino i itor cc Hil.) ag < 500. Fic. 8,9. Raimondia quinduensis (HBK.) a ig. 1000. Fic. 10. R. tenuiflora (Mart.) R. E. Fries, x 500. Fi 1G. iL. Po relia magnifractom ‘Schers) R. E. Fries, X 500. Fic. 12. Trigynaea asics Schlecht., ANNONACEAE > PuaTE 45. Pe. 1. Rollinia laurifolia Schlecht., X 200. Fic. 2. R. intermedia R. E. Fries, X 200. Fic. 3. R. rigt idiflora R. E. Fries, X 1000. Fic. 4. R. sericea R. E. Fri x 1000. Fic. 5. soap i ‘areior (St. Hil.) Saff., xX 200. Fic. 6. ae quinduensis (HBK.) Saff., 108 JAMES W. WALKER E 46. . Raimondia stenocarpa R. E. rally °500.¢ Fre. 2, oe “aid x 200. Fic. 3,4. C. brasili Vell.) Benth., 200, Pre. 5. PLaT F baillonit R. E e ( C. lanugipetalum Schery, * 200. Fic. 6. Cledtayeiiiann calophyllum Schlecht.,. - 1000. ~~ 47, Fic. oS SOs age tiaat Rvzk. 1-3. Cym Fig. 3, Fri ANNONACEAE — — 1000. Fie. 4. C. im Barb. rophyllum Rodr.; Fir: 3, % Donn. Smith, x 500. oe Ss) so Frc. 6. C. en Schery, 500. 110 . Fries, X. 200. JAMES W. WALKER ae 48. Fic. 1 ay Lanter anita baillon: * 500. R Fri . 6. Cardiopetalum Sani sales x Fic. 4,5. C. gractle 200. ANNONACEAE Ez 49. Fic - Cymbopetalum striae ‘rare Diels, X 1G. 3. Porcelia macrocrte (War 35 Re s, X . P. nitidifolia ais & Pav., 200. 00. Fic. 6. Trigynaea oblon gifolia 5. a panne (Diels) R. E. echt ge oe So ee reek 200. 111 1000. PLA mac recerta Bp sina: ) ~~ <6 50. Fic. 1,2. ~f ts pave a ay has \ ey el JAMES W. WALKER Mage a cabs spre Schlecht., < 500. Fic. 3,4. Por x rigynaea goods Seifceht.. x 500. celia ANNONACEAE 5 Gc. 1. Trigynaea cerry. Schlecht. anomalum Hk.f., X 1000. 1G. fcbclelain’ (=Polyalthia plagioneura Diels), Merr., 50 0. y, Fic. ? 200. cca 4, Fic. oh 6 aium sp. 11 3 JAMES W. WALKER Prate 52. Fic. 1,2. orang ceria eo Or 500. Fic. 3. Permechucme ania — « 500. . 4. epalum sp. (Poiyatie blagionewra Diels), * 1000. a peipeniis fete Merr.), 6,7. D. sp. (=Polyalthia pea neura Dicls s); Fig. 6, X 1000; Fig. 7, x ok. ANNONACEAE 115 x 1000. Fic. 3. . Fre. 4,5. Disebelem anomalum Hk.f., X 500. PLATE 53. Fic a agen (R. E. Fries) R. E. Fries, sahcshachis te ih N x Fic. 6. D. coronatum Becc., 2 500. 116 JAMES W. WALKER 1-3. Disepalum coronatum Bece., X 1000. Fic. 4-6. D. sp. (=Poly- 1000. PLA Fic. althia saan Merr.); Fig. 4, X 500; Fig. 5,6, x Annona Group Cymbopetalum Group Asimina Group Hexalobus Group Disulculates Anaxagorea Echinates Catasulcates 55. POLLEN Koon ONACE sig wees cinime meglephsliom Echinates— aeores Anasulcates—Pseudoxandra Desmos eli’ Inaperturates—Pa ualthia mie Disulculates—Sa@ hus sp., 4 xagorea— erates—Goniothalamus eae Hexalobus group xv : i group—A st Cymbopetalum group—Cym sje odoratissimum. grains of Asim nina, Annona, and Cymbopetalum, which are reduced by ik | one-half relative to s.) ANNONA 6. PoLLEN SCULPTURING TRENDS IN TI ts, Polyalthia - 2a. le Wale. 2. ‘Ore hea — ea coriacea. 3b. Car ga odor 3c. 1 longi- Cail photographs are scanning ct i ee 5 7 la. Malmea costaric nae 2c. Dasymaschalon sootepens . 3a. Prev folia. 4. Cymbopetalum oo st iciaeel: 118 JAMES W. WALKER PLATE os Fic. 1,2. Pseudoxandra coriacea R. E. Fries; Fig. 1, X ca. x ca. 410 _— 3,4. Malmea costaricensis R. E. Fries; Fig. 3, * ca. 490; 28. sine 5,6. Polyalthia glauca (Hassk.) Boerl.; Fig. 5, * ca. 700 * ca. 2100; oe photographs are scanning electronmicrographs. ) ANNONACEAE PLA yo Fic. 1,2. Dasymaschalon sootepense Craib; Fig. 1, X ca. 760; ca. 1664. 3-5. Orophea luzonensis Merr.; Fig. 3, > 8 a Fig. 3, - ca. 3400. (All photographs are scanning st EO 119 120 JAMES W. WALKER Late 59. Fie. 1,2. Ca a odorata (Lam.) Hk.f. & Th.; Fig. . fa. op Fig. 2, ‘ea. 3200. Fic. S. de eaaekieth odoratissimum Barb. Ro ca Fic. 4,5. Fusaea longifolia (Aubl.) Saff.; Fig. 4, x ca. 280; Fig. 5, xX s.) dr. M Cai aa: igi duende s are scanning e lectrnmumictegricke ANNONACEAE edrollinsia Walker; sib 1, X ca. 760; Fig ; Fig. 3, X ca. 140; Fig. 4, X ca. 350; ; a 2: Ae Comoran cdoratisamunt Barb. Rodr. x . (All photogr raphs are scanning el 122 JAMES W. WALKER 2 ad PLATE 61. Cymbopetalum odoratissimum Barb. Rodr. This species probably has the largest fixiform _—— grain in the angiosperms, wi ith some grains as large as 350,y. Fic. 1. Scanning graph of the proximal face, < ca. 360. Fic. 2 wlcroshaal of the distal face, « ca. 320. ANNONACEAE 123 APPENDIX: CITATION OF VOUCHER SPECIMENS Bet yi doxandra coriacea R. E. Fries (dupl. det. R. E. dees 1959), J. J. Wurdack x S. Adderley 43492-ny, P-579*; P. guianensis (R. E. Fries) R. E. Fries (det. L pba Rerint 1967), Felix Cardona 1642-—ny, P-580; P. eophl (Diels) R. E. F ries, R. Spruce 2473 (isotype )-GH, vagal Fr. polyphleba (Diels) R. E. Fries (det. L. Ariste- guieta, 1967), B. A. Krukoff 4882—ny, P-581; P williamsii (R. E . Fries) R. E. Fries (det. R. E. Fries, 1933—as Cruinanaaparna: Flawiye Williams 3960 (type)-F, P-656. Cremastosperma anomalum R. E. Fries, W. L. Stern et al. 107-cu, P-160; C. cauli- . E. Fries (det. R. E. Fries, 1947), E. P. Killip & A. C. Smith 23004-us, P-611; C. longicuspe Re E. Fries (det. R E. Fries, 1937), Llewelyn Williams 4092-r, P-654; C. Mig ir jek leg R. E. Fries, G. Klug 3069-cu, P-111; C. m ee R. E. Fries t. L. Aristeguieta, 1967), G. T. Prance et al. 3527-ny, P-548; C. novogranatense R. E Fries (det. L. gyro 1967), J. Ne ag & L. Willard 26031—us, P-612; C. pe edunculatum (Diels) R. E. Fries, G. Klug 3726-a & cu, P-112. Malmea costaricensis R. E. Fries, Walker 395+; M. haps shen (Baill.) R. E. Fries, Gaumer & Sons 23903-cH, P-105; M. diclina R. E. s (det. R. E. Fries, ] EB. n th n type )- > —107; M. doe pt (Diels) R. E. Fries (det. R. E. Fries, 1937), Eectra Williams 6226-r, P-660; M. xanthochlora (Diels) R. E. Fries ex desc., P. C. D. Cazalet & T. D. Pennington 7 796-wy, P P-566 Ephedranthus amazonicus R. E. Fries (det. L. Aristeguieta, 1967), G. T. Prance et al. ig rae P-613; E. guianensis R. E. Fries (det. R. E. Fries), Forest Dept. Brit. Guiana 4788-Ny, P-557. Pseudephedranthus he, Mee E. Fries) 1 ere Bassett Maguire & John J. Wurdack 34954 (isotype )-cH, P-124. Oxandra espintana (Spruce ex Benth.) Baill. (det. R. E. Fries), G. Klug 4273-vs, P-599; ake ra Die “ s (det. R. E. Fries, 1937), B. A. Krukoff 8177—Ny, P-570; O. krukoffii R. E. Fries, + A. Krukoff 1124 (isotype)-A, P-123; O. lanceolata ( Sw.) Baill., Bro. Leon 12012—cu, P-697; O. laurifolia (Sw.) A. Rich., E. L. Ekman 5924-a, -E.Fs Kruk i : ediocris i Jose M. Schunke hee P Ruizodendron ovale (R. & P.) R. E. Fries, G. Klug 3798—cu, P-114. Unonopsis buchtienii R. E. Fries (det. R. E. Fries, 1956), Richard Evans Schultes & Isidoro Cabrera 20078—us, P-629; U. floribunda D Diels (det. Krukoff 4806-—ny, e} aa > C . . =Pseuduvaria sp. (?), R. S. Williams 510 0-cH, P 44a: O oo Se sect Me err., M. Ramos ee hook ad Cie. Sirs O. vulcanica Elm., A. D. E. Elmer 16312 (a syntype )-A, Pp-4 heen macrocarpa Boerl., Koorders 24576, 15679—many collections (Java), P-449. Mitrephora fragrans Merr., P. Natividad F.B. 25755-a, P-481; M. git Scheff., P. W. Richards 2223-a, P_478; M. macrantha Hassk., Djoemadi N. 124 (Bogor Botanic Serr XXV. A. 4)—a, sees M. samarensis Merr., M. Ram s 1666 (is type )-cH, P-485; M. thorelii Pierre, C. Wang 36294-4, P-476; M. abet ae: C. M. Weber 1550—a, P-483; M. williamsii C. B. Rob., A. De Mesa F.B. 27464-a, P_484. he igen ie tad Merr., M. Ramos B.S. 46374-4, p-A74; P. Smeg (Bl) M ood SAN A 2948-4, P-471; P. rugosa (BL) M err., Th. Sidedien: et a ie p-470; P. versteegii Seg be Merr., L. J. Brass 7311—a, P_473. opowia fusca King, Kiah S.F. N. 31923-a, P ; P. odoardii Diels, Haji B ujang Po 14364—a, P-488; P. pachypetala Diels, R. Schlechter 18873 (type material )-a (not Annonac eae! ), P-49 af P. piocarpa (BL) si . D. E. Elmer 20735-a, P-489; 92. Phaeanthus as Becc., O. Beccari 2508-a, P-508; P. ebracteolatus (Presl.) Merr., C. A. Wenzel 1737-a, p-51 al. Trivalvaria peril (BI.) Miq., Kiah S.F.N 35393-a, P-512; T. nervosa (Hk-£. & Th.) J. Sincl., E. J. H. Corner S.F.N. 29032-a, P-513. Guatteria oliviformis Donn. Smith, Walker 413. err ng sessiliflora (Benth.) R. E. Fries (det. R. E. Fries), A. Ducke 23892-— us, P-610 nace brasiliense Benth., Bassett Maguire et al. 36371-—cH, P-125. et al. 54545-ny, . det. asse ny, P-533; A. brevipes Benth. in Hk. f. (dupl. det. E. Fries, 1955), Bassett Maguire et al. 29792—-ny, P—534; A. vostaricensis R. E. Fries (author s preserved 1956 ichard S$. Cowan & Jon 9 Pp-535; : D R. . Fries, B. A. org Pee i P-652; A. minor Diels ex R. Lo er (cited in FI. Peru), E. P. Killi C. Smith 28610—us, P-618; A. multiflora R. E. Fries, Forest Dept. Brit. Guiana Soa P_537; A. mutica R. E. Fries (det. R. E. Fries, 1937), 128 JAMES W. WALKER B. A. Krukoff cave. P-538; A. phaeocarpa Mart. (det. R. E. Fries), A. Ducke 19631-vs, P-619; A. prinoides (Dun.) St. Hil. (det. R. E. Fries, 1956), Richard S. Cowan 38515-ny, P_-539 Piptostigma (Brieya) fasciculatum (De Wild. ) Boutique, C. Vigne 2057—a, P-352; P. glabrescens Oliv., G. Mann 1792-cu, P-351 and G. Zenker 505-cu, P—350; P. multi- nervium Engl. & Diels, G. Zenker 2263 (isotype )-a, P—349. Xylopia aethiopica (Dunal) A. Rich. , Kersting A. 181-a, P-723; X. africana (Benth.) Oliv., Deistel 151-4 , P—724; X. aromatica (Lam.) Mart., Alexander F. Skutch 4339-a, P_699: ; 30382-a, P-718; X. frutescens Aubl., Walker 138; X. laevigata (Mart.) R. E. Fries A. Claziou 1530—a, P~709; X. macrantha Tr. & Pl., W. N. Bangham 490-a, P-700; X. micans R. E. Fries, G. Klug 3034 (isotype )-cu, P-711; X. nitida Dunal, oe 1046-cu, P-706; X. poeppigii R. E. Fries, G. Klug 3048-a, P-707; X. polyantha R. E Fries, B. “A Krukoff 8150—a, P-708; X. sericea St. Hil., Riedel 2697-a, P-710. Fusaea decurrens R. E. Fries, Richard Evans Schultes & Isidoro Cabrera 16039-cH, P-103; F. longifolia ( Aubl.) Saf, (det. L. Aristeguieta, 1967), G. T. Prance et al. 4594-ny, —560 Dueeanthu grandiflorus R. E. Fries (det. R. E. Fries, 1950), J. Murca Pires 444-Nny, Cananga ate (Hk.f. & Th.) Finet & Gagnep., M. Poilane 15082-a, P-272; C. odorata (Lam.) Hk. & Th., Walker 123. Meiocarpidium lepidotum (Oliv. ) Engl. & Diels, F. J. Breteler 1398—a, P-271. Neostenanthera eeenen (Engl. & Diels) Exell, G. P. Cooper 416-cu, P-407; N. hamata ( Benth.) Exell, G. P. Cooper 371-F, P-666: N. myristicifolia (Oliv.) Exell. — 2820-a, p4 wet ceus a W. T. Tsang 30097 (isotype )-a, P_453: G. curtisii King, Nur 11191-a, P-457; G. grandiflorus (Warb.) Boerl., L. J. Brass 8002—a, P—465; G. nitidus Merr., M. Ramos , P-45 i P ; G, Pierre ex Finet & Gagnep., L. Pierre—no number on sheet, but probably Pierre 1796 Leger a syntype )-a, P_456; G. dehaaines Airy-Shaw, J. Sinclair & Kadim 10429-a, Richella monosperma A. Gray, John W. Gillespie 3652-cu, P-505. Monodora angolensis Welw.., Fg ge ce P-523; M. erat Benth., G. Cooper 83—a, P-524; M. junodii LE. d 39-ny, P-569; M. se igen (Gaertn. ) Duna F F. I pearl et al. oh ae sae M. tenui- folia Benth., Zenker 64—cu, lona campanulata Engl. & Diels, M. Aubreville 570-a, P-528; I. congolana (D Wild. & Th. Dur.) Engl. & Diels, R. Germain 278-us, P-644; I. hexaloba (Pierre ex Engl. & Diels) Engl & Diels, J. D. Kennedy 1568-a, P-530; I. pilosa Diels, Goss- weiler 9063-vs, Uvariastrum hexaloboides (R. E. Fries) R. E. C. E. Duff & R. G. Miller 300/35-a, P-344; U. pierreanum ae gs D. Dats 2571—a, P-345; U. zenkeri ae & Diels, G. Zenker 481-—cu, P Uvariopsis penta Keay, D. H. Linder 580-a, P-521; U. zenkeri Engl., G. Zenker 515-cn, P-522. Hexalobus monopetalus (A. Rich.) Engl. & Diels, H. J. Schlieben 7432-ny, P-563. ANNONACEAE 129 Cleistochlamys kirkii (Benth.) Oliv., Menyharth 790-a, P-233. Diclinanona calycina (Diels) R. E. Fries (det. R. E. Fries, 1933), G. Klug 96-vs, P-643. Asimina longifolia Kral, R. Kral 2335-cu, P-188; A. obovata ( Willd.) Nash, L. J. Brass 14757-cu, P-189; A. parviflora (Michx. ) Dunal, R. Kral 4219-cH, P-190; A. pygmaea (Bartr. ) Dunal, R. ar 2772-cH, a ee A. reticulata Shuttlew. ex Cha R. Kral 6358—cuH, P-192; speciosa Nash, Kral 2175-cnH, P-193; cuca Small, R. Kral 5372-cu, ewe A. triloba ee Dunal, cultivated, Arnold Arboretum, P-3 eeringothamnus pulchellus Small, e Kral 2129-cu, P-195; D. rugelii (B. L. eae ) Small, R. Kral 2509-cn, P—19 ANNONA L. Sect. Annona: A. aurantiaca Barb. Rodr., B. A. Krukoff 2054—a, P-127; A. donee Mart. aff., Herbert H. Smith 2418—cu, P_-166; A. montana Macf. emend. R. E Be he Ekman H 9983-a, P-126; A. muricata L. (author’s preserved hid oe voucher ), P-4. Sect. Ulocarpus Saff.: A. crassiflora Mart., E. Hassler 5131—a, P-128; A. purpurea Moc. & Sesse ex Dunal, G. F. Gaumer & Sons 23295-cu, P-129. Sect. Campicola R. — Fries: A. dioica St. Hil., E. Hassler 12325-cn, P-130. ect. Psammogenia : A. — R. E. Fries, Richard Evans Schultes & Isidoro Cabrera 17530 _aotayent P-150 Sect. Phelloxylon Saff.: A. glabra ie Walker 432. Sect. Helogenia Saff.: A. paludosa Kobl, J. M. Pires 51904-cu, P-131; A. senegalen- sis Pers., R. P. Tisserant s.n.-a, P-168 and E. P. Phillips 1540-a, P-169; A. stenophylla Engl. & Diels, ee G. Curtis 276a—cH, P-171; A. tomentosa R. E. Fries, Riedel 2648 (isotype )-a, P. Sect. wien all A. acuminata Saff., F. M. Salvoza 1001—a, P-139; A. angusti- folia Huber., Ducke 107—a, P-132; A. *ordifolia Poepp. ex Szyszyl., Richard T. Martin & T- Timothy Plowman 1791-cx, P-165; A. hypoglauca Mart., H. H. Rusby 1241-cn, P-136; ‘A. jahnii Saff., H. Pittier 11732-a, P-134; A. jamaicensis Sprague, Walker 280; = sericea oe J. S. De La Cruz 3739-cn, P-133; A. "ag Saff., Sect. oe an talum se dint St. Hil, P- sia 16643—cn, P-141; re nutans R. E. Fries, E. Hassler 12355-a, te Sect. Oligantha R. E. Fries: A. amambayensis oe E. Hassler 10729 (isotype )-a, P-173; A. cacans Warm., J. E oui Leite 2098—a, P-142. Sect. Atractanthus Saff.: A. acutiflora Mart., L. Riedel 826—a, P-143; A. ambotay Aubl., Ducke 542-a, nin A. haematantha Miq., Bassett Maguire 24470-cu, ee ra S. Wats Sect. Atta Mart.: A. cherimola Mill., Walker se gee A. a hee 508 c. & Rendle, Wm. Harris = 648-cH, are A. eden te Stan & Steyerm, GL Lundell 6 6651-cu, P-174; A. reticulata L., Walker 259; A. squamosa L., Walker Sect. er a Saff.: tticri Donn. Smith, Alberto M. Brenes 4100-Ny, P-596; A. scleroderma Saft., a i Yandel ean P-147. Sect. Ilama Saff.: A. diversifolia Saff., Geo. B. Hinton et al. 7863—a, P-148; A. mi aisiahasiieiber Donn. Smith, Chas. C. Deam "6191 (isotype )-cH, P-149. Sect. ae Saff.: a A. Rich., pe Wilson 9388-cu, P-177; A. crassi- venia Saff., C. Wright ine (holotype)-cu, P Sect. Annonula Saff.: A. cascarilloides Db ge in Griseb., C. Wright 1848 (isotype )- cH, P-181; A. haitiensis R. E. Fries L. Ekman H 15260 (iso — P-182; is Leon & Alain, Bro. palette 6144-cu, D180, A. se rophylla Saff., Carabia 3779-cu, P-151. 130 JAMES W. WALKER Sect. — Baill.: A. bicolor Urb., E. L. Ekman H ey ( ae P-183; A, dumetorum R. E. Fries, E. L. Ekman H 12351 Big ely -A, P-153; A. globiflora Schlecht., Cc. C. Pringle 3796—a, P-152; A. rosei Saff., J. N . Rose 4038 (isotype)-cn, P-154, Rollinia emarginata Schlecht., E. Hassler (leg. T. Rojas) 9702—a, P-737; R. exsucca ( .) A. DC., W. E. Broadway 5905—a, P-733; R. intermedia R. E. Fries, E. Hassler ae parviflora (St. sas ee J. Nadeauo s.n.-a, P-739. Raimondia cherimolioides wet & Pl.) R. = — Wilson Popenoe 1201-vs, oe R. quinduensis (HBK.) Saff., A. E. Lawr e 170-Ny, P-582; R. stenocarpa R Fries, Oscar ae 3459-a, P-Sid, R. fetiuiflora ( Mart. ) R. E. Fries, B. A. Krukoff 8813-a, P ymbopetalum yg on R. E. Fries, Manuel Martinez 95—a, P—730; C. goes og Duke 4 Wek Benth., J. A 848-cu, P-731; C. costaricense (Donn. Smith) R Fries, ge 133, P86 (author’s preserved material); C. — R. E. Fries (det. R. E. “i 1955), Geo. B. Hinton et al. 10257-us (type cited as Hinton et al. 1027), P. 7; 6. ‘anugipetalum Schery, W. L. Stern et al. 394—us, P-638; C. longipes Benth. ex Diels (det. R. E. Fries), Erik Asplund 13243-ny, P-549; C. odoratissimum Barb. Rodr. se R. E. Fries, 1937), B. A. Krukoff 4 4646-Ny, P-550; C. penduliflorum (Dun.) B Walker 428; C. ees Donn. Smith, Geo. B. Hinton et al. 13788-cH, re C. sp., Walker feces mires ort ee Schlecht. (det. L. Aristeguieta, 1967), H. S. Irwin & R. Soderstrom 6964—ny, P-543. Teresi macrocarpa ean ) R. E. Fries (det. R. E. Fries), P. R. Reitz 5891-ws, P-601; P. magnifructum (Schery) R. E. Fries, W. L. Stern & K. L. Chambers 43-a, P-202; P. nitidifolia Ruiz & Pav. (det. R. E. "Fries , 1935), G. Kiug 3750-us, P-602; 1 aa steinbachii (Diels) R. E. Fries (det. R. E. Fries, 1937), B. A. Krukoff 5676—-ny, P-577. Trigynaea caudata (R. E. Fries) R. E. Fries (det. R. E. Fries, 1956), Forest Dept. British Guiana 7790-ny, P-583; T. ecuadorensis E. Fries, Erik Asplund 9059 isotype )-ny, P-598; T. oblongifolia Schlecht. (det. R.:E: Fries ), FO; oth tr 7974—ny, P. Hornschuchia fees Nees von Esenbech, Riedel 711-cu, P-201. D. plat petalum Merr., C. G. G. J. van Steenis 9843-a, P. "3 (=Polyalthia af es Merr.), A. Petelot 6362-a, P-288; D. sp. (ctPolyalthia plagi How 70331—a, P-274. INDEX TO GENERIC POLLEN DESCRIPTIONS Alphonsea 26 sect. Atractanthus 35 sect. Atta 35 sect. Chelonocarpus 36 lama 36 sect. Annonella 36 Bocageopsis 22 Cananga 31 Cardiopetalum 37 Chieniodendron 26 Cleistochlamys 33 3 72) siesta iste 26 Fus usaea Goniothalamus 31 spar 27 tteria 29 Cuntheriapals 29 Heteropetalum 29 Hexalobus 3 Oncodostigma 27 Onyc a 22 Orophea Oxandra - etna see Friesodielsia Papu Ff Phae aire 29 Pipostigma 30 Platymitr. = Polyalthia Si doar 25 Popowia a 28 Popowia (African) 24 Porcelia Pseudephendranthus 22 Pseudoxandra 21 Xylopia 30