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MONOGRAPH OF THE ISOETACEAE?
NORMA E, PFEIFFER
Associate Professor of Botany, University of North Dakota
History

The name IJsoetes was first mentioned by Linnaeus in 1751
(Skanska Resa, 417, fig. 1), although the common European
species of the group had been previously known for many years
and variously recorded under different names. In 1753 Linnaeus
(Species Plantarum 2: 1100) definitely established the genus
Isoetes, as follows:

‘lacustris. ISOETES. It. Scan. 417. t. 419. Nov. gen. 1109.
Marsilea foliis subulatis semicylindricis articulatis.
Fl. suec. 996. [ Stockholm, 1745].
Calamaria folio longiore & graciliore. Dill. muse.
541. ¢. 80. f. 2. [Oxford, 1741].
Subularia lacustris f. Calamistrum herba aquatica
alpina. Raj. angl. 1. p. 210. ¢. 210. [London,
1677].
Habitat in Kuropae frigidae fundo lacuum.’’

In the following year Linnaeus (Genera Plantarum, 486.
1754) characterized the genus, relating the structures to those of
seed plants. The male flowers were described as solitary within
a base of inner leaves, with no corolla, but with a calyx of cordate
scales, acute and, sessile, and with stamens having subrotund,
unilocular anthers, but no filaments. The female flowers were
reported as solitary, within a base of outer leaves of the same
plant, with the calyx and corolla situation as in the male. The
pistil was described as having an ovate embryo within a leaf, but
the style and stigma were supposed to be hidden. The fruit was
considered to be a capsule, subovate and bilocular, concealed in
the base of the leaf, and the seeds to be numerous and globose.
In an earlier account (Skanska Resa, 417. fig. 1. 1751), Linnaeus
expressed jubilation over finding flowers, whereas Dillenius had
seen only fruits.

4Special investigation carried on mainly at the Missouri Botanical Garden.
Issued Nov. 27, 1922. (79)
Ann. Mo. Bot. Gard., Vol. 9, 1922.

[Vol. 9
80 ANNALS OF THE MISSOURI BOTANICAL GARDEN

Crude as is the description of Linnaeus, it surpassed the earlier
accounts. Ray, who provided the earliest account, credited D.
Lloyd with finding the material in an alpine lake, and remarked
that “of this plant, one sees nought but leaves and roots, and
knows not from what source it comes directly.”

Dillenius developed a little greater detail in regard to the
structure. He described two plants, similar in their fleshy tubers,
but differing in the shorter, coarser, incurved leaves of the one,
and the finer, longer, erect leaves of the other. The latter, con-
sidered synonymous with J. lacustris L., is described as having
“a, root harder than a leek, less tuberous, less thick,” but other-
wise having the same texture of leaf, color, seeds, etc. In the
description of the short-leaved form, the channels in the leaf and
the transverse septa are brought out as they are in the diagrams
of the fine-leaved plants. The plants are reported as growing “‘in
great abundance in very long, deep ponds near Llanberry” and
in mountain lakes.

Scarcely more enlightening is the account of the next species
of Isoetes to be recorded. In 1781, J. coromandelina, similar to
I. lacustris L., but larger, was reported by Linnaeus fil. as growing
in wet places, submerged in the rainy season, in Coromandel.
Attention in the description is chiefly drawn to the filiform, erect,
glabrous character of the leaves and the broadened membrana-
ceous leaf-bases which form the bulbous portion of the plant.

The first detailed account of the development of [soetes occurs
in connection with the description of a third species, J. setacea,
by Delile* in 1827. He carefully observed the life-history through
the seasons, and as a result laid a better morphological basis than
his predecessors. A comparison is made with Lycopodium but
the author decides that Jsoetes resembles the lily or Juncus more
in its embryo characters. However, the genus is finally placed
between Marsilea and Lycopodium, with interpretations of all
structures made on the basis of seed-plants.

The following year H. G. L. Reichenbach published the first
account in which the family name for [soetes is used, here as
Isoeteae. This, or similar forms, as Isoetineae, is used by all
the subsequent workers cited up to the paper of Underwood,
where the modern /soetaceae is used for the first time. There ~
is a good deal of confusion in the references given by some of

‘Delile. A. R. Examen de la vegetation de 1’ Isoetes setacea et exposition de
ses caractéres. Mus. Paris Mem. 14: 110-119. pl. 6-7. 1827.

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 81

the earlier authors, as, for example, Schnizlein, who credits
Bartling as the originator of the family name in the text and
Richard in the legend on the plate illustrating his paper.

References occur twice which suggest that Claude Richard was
responsible for the idea of a separate family containing the
Isoetes species. Delile himself in 1827 places the genus between
Lycopodium and Marsilea, but says that Richard believes it a
family distinct from Lycopodium and other ferns. Again, in
1844, we have the statement of Bory that Claude Richard be-
lieves that /soetes ought to be considered as a separate family
from other ferns. It has been impossible to find any account
published by Richard himself in regard to this point.

Within a short interval after Delile’s work on I. setacea Bose,
much interest was stimulated in the genus through the work of
two investigators, A. Braun and Durieu de Maisonneuve. The
former developed not only systematic, but much morphological,
knowledge in regard to various species. The latter was chiefly
instrumental in augmenting systematic information, especially in
regard to Algerian species.

In 1867, Milde’ brought together forms that occur within a
relatively much larger territory than had been previously con-
sidered. An idea may be obtained of the various contributions,
especially.of Braun and Durieu, from the fact that by this time
the number of species within the range of Milde’s work is 15.

A synopsis of the species of Jsoetes was published within a
little over a decade by Baker’, who later incorporated the same
manuscript with little additional material in his ‘Fern Allies’. In
this synopsis, 46 species are brought together by the author
whose primary divisions are on the basis of geography.

Following Baker’s work, Motelay and Vendryés* monographed
the genus, including 47 species. The work is enhanced by the
illustrations which include those of many spore forms. Not a
few of the forms considered in Baker’s synopsis and in the
monograph by Motelay and Vendryés were due to the activity
of Engelmann.‘

Beare J. Filices Europae et Atlanticis, Asiae minoris et Siberiae, 274-290.
*Baker, J. G. A synopsis of the species of Isoetes. Jour. Bot. 18: 65-70,

105-110. 1880, and Fern Allies, 123-134. 1887.

*Motelay, L. et Vendryés. Monographie des Isoéteae. Soc. Linn. de Bordeaux,
Actes 36: 309-405. pl. 8-17. 1883.

‘Engelmann, G. The genus Isoétes in North America. St. Louis Acad. Sci.,
Trans. 4: 358-389.1882.

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82 ANNALS OF THE MISSOURI BOTANICAL GARDEN

In 1882, in a systematic treatment, he considered the North
American forms to the number of 15 species with their varieties.
The contribution is of exceptional value as an account of the
genus and includes an excellent treatment of the history of the
genus in this country.

Almost simultaneously with this work appeared Underwood’s*
publication in which he first used the modern form of family
termination in Jsoetaceae. A lucid account of 14 forms in North
America is supplemented with good generalizations on the dis-
tribution of forms.

Within more recent years, there has been no outstanding ad-
dition to our systematic knowledge of the family through the
activity of European investigators. In America, there has been
a material increase in information, especially concerning the
representatives on the eastern border, through the work of Dodge’
and Eaton.’ These authors, as is true of most of their predeces-
sors, published less comprehensive studies in various journals.

In a less technical consideration of the family, Clute* has re-
cently recognized 21 species in the United States. This repre-
sents the latest account of the genus as a whole in America.
There have, however, been treatments over more restricted ranges
in various manuals and floras. The more important of these are
cited in connection with the systematic treatment of the family,
and therefore require no further consideration here.

Loca NAMES AND Economic USEs

The first popular name recorded for [soetes is that given by
Dillenius in 1741, where “quillwort” and “Merllyn’s Grass” are
cited. That the former name has survived is well known to us
in America, and Clute’ is authority for the statement that Isoetes
lacustris is still called Merlin’s grass in northern Europe.

Linnaeus in ‘Skanska Resa’ reports that the natives refer to
Tsoetes as “Brachsen grass.” Ascherson and Graebner (Syn.
Mitteleur. Fl. 1: 163. 1896-98) give the following: “Brachsen-
kraut: dan: Brasenurt: poln: Poryblin. bohm. Sédlatka.”

*Underwood, L. M. Our Native Ferns and Fern Allies, 121. 1882.

"Dodge, R. Ferns and Fern Allies of New England. 1896.

*Katon, A. A. The Genus Isoetes in New England. Fernwort Papers. 1900.
‘Clute, W. N. The Fern Allies, 209-254. 1905.

‘Clute, W. N. loc. cit. p. 224.

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 83

The technical name for the genus seems to be in common use.
By derivation, it indicates the evergreen character of at least
some of the species “equal at all seasons of the year” or through-
out the year, from icoc, equal, and etoc, year. Some forms are,
however, false to the name in that no leaves, sterile or otherwise,
seem to survive the winter or dry season. The perennial char-
acter of the corm is not to be doubted in such plants though
the leaves do disappear.

In the older accounts, it is of interest that an economic relation
was usually mentioned. So Ray (1696) says that the plant
“gives out a melancholy fluid, used in affections of the spleen
and liver. It is accredited somehow with sharing the habit of
the plants with which it grows.” Dillenius, on the other hand,
cites as its use that the plant is eaten by fish.

That birds are not disinterested in the food use of Isoetes is
evidenced by the story of Durieu, who first saw I. histrix bulbs
under rather unusual circumstances.* The peculiar organs were
found in the stomach of a bird which was shot down by a mem-
ber of his party. The real nature of the plant structures was only
recognized in subsequent field work when similar bulbs were
discovered growing on the hillsides of Algeria. That a terres-
trial form resembling this Algerian plant, J. Duriaei, is eagerly
devoured by pigs, is also quoted from the statements of Bory de
Saint-Vincent.

In the eastern United States, one observer says that ducks are
fond of the bulbs or sporangia masses at the base of the plant and
will tweak them off, allowing the leaves to float. Clute says
of J. Braunu Dur. that the crisp bulbs are favorite morsels with
muskrats, and that cattle are said to feed upon the leaves of any
species available.

The corms are said to have been eaten occasionally in Europe
by human beings, though the taste is variously described as
earthy and unpalatable (Clute) or acid and bad-tasting (Delile).
Undoubtedly the presence of starch and oil give the spores and
corms food value, whether they be palatable or not. The dis-
tribution hardly seems extensive enough to make consideration
of development of a taste for them worthy of attention. The
plants probably are of greatest economic use at present as a
source of food for the lower animals mentioned.

*Bory de Saint—Vincent, Sur les Isoétes et les espéces nouvelles de cette
famille decouvertes en Algerie. Compt. Rend. Acad. Paris 18: 1167. 1844.

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84 ANNALS OF THE MISSOURI BOTANICAL GARDEN

GENERAL MoRPHOLOGY

The genus limits of /soetes are very sharp and clear, so that
there is no difficulty in recognizing a member within it. How-
ever, sections within the genus prove more difficult of discovery
and definition. In the past, much emphasis has been laid by
systematic workers in this field on the relations to water. En-
gelmann used the subdivisions “submersed, amphibious, and
terrestrial” as his primary subdivisions. Motelay and Ven-
dryés used two main headings, thus:

I. Aquaticae
Submersae
Palustres
Amphibiae

II. Terrestres

It has seemed that the ecological relations might not be ade-
quate as bases for primary divisions of the genus. The attempt
has therefore been made to utilize more constant features of a
morphological character. It seemed that the spore characters,
related as they are to fruiting rather than to vegetative stages,
might prove more consistent. It has been found that the mega-
spores, especially, run fairly constant in size and markings. In
conjunction with these spore characters, it is necessary for safety
in classification to take into consideration other features, such as
the velum, which proves fairly dependable as a character, the
lobing of the plant corm, usually a reliable feature, and other less
constant characters like the ligule and the presence and number
of peripheral strands of supporting tissue in the leaf. These
features are considered in greater detail in the subdivision which
follows, i. e., morphology.

In the genus the habit of the body is definitely characteristic
and easily recognized in perfect specimens. The stem portion
is unusually compact, both vertically and horizontally, and gives
rise to a group of rush-like leaves in crowded spiral formation,
and to many dichotomously-branched roots.

Stripped of its leaves and roots, the perennial stem is readily
seen to have two or three more or less deep furrows, which result
in producing a two- or three-lobed body. The number of lobes
so produced is characteristic of the species concerned, save in
the rare cases where three lobes may be found in a usually bilobed
form or four in a trilobed. The roots appear chiefly in the fur-

1922]
PFEIFFER—MONOGRAPH OF THE ISOETACEAE 85

rows, somewhat obscuring the real form of the stem in many
cases.

The upper portion of the stem or corm is flattish or concave;
in growth, the central lowest part gives rise to the newest leaves,
while the successively older ones are pushed out to the periphery
by the newer growth. There is no apical cell responsible for
stem growth, according to Farmer (’90), although according to
the evidence seen by Scott and Hill (’00) there may be one.

Anatomically, the compact stem has proved an interesting
problem. The vascular cells are centrally located in a single
group, which has been interpreted either merely as a union of
the leaf-traces (Hegelmaier, ’72) or as a small distinct stem stele
plus the leaf-traces (Scott and Hill, ’00).

Although the xylem character of the tracheids in this central
region seems clear, there has been much discussion as to the
significance of the zone immediately about it, the so-called
“prismatic layer.” According to Russow (’72) and Scott and
Hill (700) this undoubtedly contains distinct phloem elements.
According to Farmer (’90), Wilson-Smith (’00), and Stokey
(09), the phloem interpretation is invalid, because of the in-
ability to identify sieve structures here. The last-named worker
sees only xylem cells as representatives of conducting tissues
in this region.

A meristematic zone addg new tissue to the prismatic layer
and to the outer parenchyma region. The latter, cortex in nature
and position, usually dies at the margin, and in time is sloughed
off, although the accumulation of dead cells may be appreciable
before being worn off. This is especially true in terrestrial forms
where the leaf bases are persistent and the dead cortex remains
in place over successive seasons. More frequently, however, the
wearing away tends to balance in part the increase in diameter,
so that even very old stems are not excessive in size.

The roots are interesting in that they branch dichotomously.
In anatomy, they are peculiar in being collateral endarch. The
vascular bundle upon emergence from the central stele is sur-
rounded by parenchyma which is replaced by a small group of
phloem cells on the side away from the axis of the stem (Stokey,
09).

In the early growth of the sporophyte and before sporophyll
production in each growing season, sterile leaves are usually
produced. These are similar to the fertile leaves or sporophylls

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86 ANNALS OF THE MISSOURI BOTANICAL GARDEN

which appear later except for the absence of the sporangium.

The leaves consist of two regions, a long narrow extension
widening into a sheathing base, the margins of which are mem-
branaceous in character. The lateral extension of the base and
the longitudinal extension of the transparent edges may serve
in some degree as diagnostic characters, though there is variation
according to the size of the plant, position of the leaf, and es-
pecially the depth of the corm im the soil.

On the upper or inner face, each leaf bears a delicate little
extension of tissue, free end uppermost, lying parallel to the leaf
surface. This ligule in face view appears most often triangular,
sometimes much elongated, sometimes subulate or rounded. To
some extent, the form and size of the ligule may prove of value in
diagnosis, though not constant enough to be of determining
caliber. Especially in older leaves, it may be imperfect through
tearing of the delicate tissue. The ligule was called the
“calyx” by Linnaeus, and “processus glandulae” by Cesati and
DeNotaris (58). The former interpretation may be understood
in view of the attempt to homologize structures in Isoetes with
those in flowering plants. The latter term is clear when one sees
the swollen imbedded portion of the ligule, called the “glos-
sopodium” by A. Braun (’64). This, in section, is sharply dis-
tinguishable from the adjacent tissues of the leaf, though in-
timately grown to them, and might readily be compared to a
glandular structure.

Wilson-Smith further terms the layer of large glandular cells
about the glossopodium and next the leaf tissues proper the
“sheath” and distinguishes between the dead marginal and apical
cells, and the living central region of the tongue-like extension
of the ligule.

The origin of the ligule has been shown to be a single super-
ficial cell (Hofmeister, ‘62, and Wilson-Smith, ’00) of the leaf,
which develops very rapidly to form a short row of cells, soon
becoming a plate, except in the basal portion which, as indicated
above, becomes massive.

The insertion of the ligule is sometimes marked by a fold of
tissue immediately below the base, to which Braun applied the
name “labium”. This is apt to be fairly consistent in the degree
of development within the species, but is so small a character
that it is difficult to use it in a diagnostic fashion.

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 87

In early stages of leaf development, the ligule is longer than
the leaf, which is originally a low rudiment, soon developing
into an elongated structure with a broader base. ‘The latter
develops more rapidly at first both in size and differentiation;
later the distal portion exhibits greater growth, resulting in the
elongated part above the ligule. In this region, there occur four
long air-channels, intersected at intervals by transverse par-
titions. The cavities are produced while the upper part of the
leaf is still meristematic. Groups of cells lose their contents, the
cells break apart through solution of the pectins of the middle
lamella, a process followed by disintegration of cells while inter-
vening patches fail to change and so form the septa. The con-
tinued growth of the living cells at the periphery brings about
increase in length and width of the cavities between these dia-
phragms.

At the center of the leaf in the tissue between the channels,
the single collateral vascular bundle is located. Peripherally, in
the layers of green tissue, may occur strands of supporting
or mechanical tissue, which have commonly been called “pe-
ripheral bast.” Since there seems to be no reason for assign-
ing a conducting function to the thick-walled cells in these
groups, the term peripheral strands is here substituted for bast.
By far the most common distribution of these strands is that in
which there is one at each side angle of the adaxial face and one
each at the adaxial and abaxial ends of the! middle partition.
When six groups are present, the other two are at the ends of the
cross-partition. Any accessory strands produced are not usually
so well developed as these six.

In leaves which are fertile, the sporangia occur singly at the
base, on the inner face of the leaf. At maturity, each sporan-
gium appears to be fitted into an elongated or round cavity,
termed the “fovea” by Braun. From the margins except at the
base there may be a fine, one-celled layer of tissue, the velum, ex-
tending over the sporangium to a greater or less degree. Within
limits, the degree of development of this velum may be useful as
a diagnostic feature. Some forms characteristically show no
velum formation, as Jsoetes Malinverniana; in I. Engelmanni, the
velum is usually narrow but evident; in J. Orcuttz, it is complete,
covering the sporangium all the way to the base. In the form
I. Braunii, the American ally of I. echinospora Dur. it varies
from 1/3 to 2/3, or occasionally even more extended.

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88 ANNALS OF THE MISSOURI BOTANICAL GARDEN

Where the sporangium wall is exposed, it, as well as the adja-
cent epidermal tissue of the leaf base, may show wall thickening
in groups of cells, resulting in a brown-spotted effect under
magnification. When the patches of brown sclerenchymatous
cells are very numerous, the brown coloring is readily noted; an
extreme case is found in J. melanopoda Gay & Dur., where the
specific name is derived from the deep coloring of the bases of the
leaves.

The sporangia are of two sorts, occurring in the same plant,
though in some cases at different seasons. A striking example
of probable difference in time is found in the East Indian form.
The description of J. coromandelina L. fil. and I. brachyglossa
A. Br. both left the condition of the microspores and micro-
sporangia in doubt because of the failure to obtain microspor-
angiate material. In a collection sent from India through the
courtesy of Dr. W. 8S. Dudgeon, all the sporangia appeared to be
megasporangiate. Yet with diligent search about the bases,
among old megaspores, microspores, probably from the previous
season, were found.

The sporangia of the two kinds have been found to originate
and pass through their early stages in similar fashion (Bower, ’08,
Wilson-Smith, 00). It is only in later development, and es-
pecially at maturity, that the heterosporous nature becomes
striking. The sporangium initial is a transverse row of super-
ficial cells, which by periclinal divisions, give rise to wall layers
and to a sporogenous mass. The velum may be derived from a
part or the whole of the upper tier of cells arising from the
division of the initial cells (Wilson-Smith, 00). According to
the results of Scott and Hill, the velum arises from the tissue
between the ligule and the sporangium initial. The growth here
in the “sella,” a term given by A. Braun, first gives the labium
by upward growth, and then the velum by downward extension.

Bands of cells in the sporogenous region become sterile, form-
ing the trabeculae, eventually more or less plate-like cross exten-
sions into the spore mass, bordered by a tapetal layer (Wilson-
Smith). The trabeculae are unusually large and distinct in the
megasporangia, in which some of the potentially sporogenous
cells develop at the expense of others. The large functional -
ones produce tetrads of megaspores, whereas in the micro-
sporangia, all the sporogenous mass, except the trabecular strips,
produces microspores.

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 89

The group of microspores from a mother cell may show bi-
lateral or tetrahedral arrangement. In either event, the freeing
of the spores soon allows the loss of the sharpness of the original
form, so that the microspore is more or less rounded at the two
side angles, though with a sharper angle on the third side, paral-
lel to the long axis. Usually the long diameter of the microspores
will fall between 20 and 40u, with the width or thickness less
than 25u. In some forms, there are markings of the exospore,
resulting in papillose or spinulose effects. More rarely, there may
be the development of a wing extension or crest, especially on
the side opposite the sharp angle. There is little variation in
coloring in the microspores, which are generally ashy, fawn, or
cinnamon-brown. As diagnostic features, the microspore size,
primarily, and markings and coloring, secondarily, may be used
to advantage.

The study of the megaspores has many advantages over that
of microspores. Their greater size, due to the functioning of
fewer cells in the sporangium at the expense of other potentially
sporogenous cells, makes for facility in handling. The size varies
in the species between 250 and 900u in general, with a much
smailer range in the individual species. The coloring of the
megaspores in most cases is white or gray-white but in cases of
exceptions, as the black in J. melanospora Engelm., the color is
a useful diagnostic character. Most important are the markings
or sculpturing on the surface of the siliceous exospore. The
spores, formed in tetrahedral groups, retain the impression of
their three neighbors on three faces, which are separated by
rounded or sharp ridges which converge at the apex (sometimes
called commissural ridges). The fourth face of each spore, ori-
ginally the free surface in the tetrad, is hemispherical or but
slightly flattened, and is separated from the three more nearly
plane faces by the ridge called the “equator.”

The sculpturing, consisting of spines, of small tubercles or
warts, or of reticulate markings, may be similar on all faces, or
may differ from the other three on the fourth or basal side.
These characters within the species seem as conservative features
as occur in Jsoetes and therefore of great value diagnostically.

The sporangia in Isoetes lack a definite device for dehiscence,
and hence both types of spores are released only upon decay of
the sporangium walls. As a result, there is an accumulation of

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90 ANNALS OF THE MISSOURI BOTANICAL GARDEN

the spores about the bases of the still active leaves, from which
material for study of the gametophyte stages may be drawn.

The microspore upon germination gives rise to a small len-
ticular cell at one end, which has been called the prothallial cell.
The remaining cell, the antheridium initial, divides in such
fashion that a single wall-layer is formed, investing a central
region of four cells, each one of which produces a large multi-
ciliate, spirally coiled sperm (Belajeff, ’85).

The megaspores, well filled with storage material of starch and
oil, are reported by Campbell (’91) as undergoing free nuclear
division to the number of 30-50 nuclei, when division walls begin
to appear at the apical end, later along the margin of the spore,
and eventually in the central portion. There is some increase in
size with development, as a rule, so that there is cracking along
the three ridges converging at the apex. It is in this region that
the archegonia develop, so that three lines of these up to the
number of thirty can be observed, if fertilization is prevented. Ac-
cording to Campbell, the archegonium initial divides trans-
versely, giving rise to the cover cell (later producing four tiers of
neck cells) and the inner cell (later dividing into the neck canal
and the central cell). The neck canal nucleus divides, but ac-
cording to Campbell, no wall is produced and it remains a short
wide cell. In other species, a longitudinal wall has been reported
by Miss Lyon and Arnoldi. The central cell divides to produce
an egg and a ventral canal cell quite as broad as the egg.

When mature, the archegonium shows the usual canal to the
egg, due to disintegration of the canal cells, which allows the
entrance of sperms and the subsequent fertilization of the egg.
In the development of the embryo, the first stage (Campbell)
is transverse division into two cells, followed by a quadrant stage
in the most regular cases. The two lower quadrants are reported
as giving rise to the foot, one of the upper to a leaf and one to a
root. Later, a stem tip develops between the leaf base and the
root, in such manner that its origin may be from either. Very
early in the development of the leaf rudiment, the ligule cell
begins its activity. Division of cells and elongation is rapid
in all regions, so that the stages pass quickly. The embryo ~
sporophyte soon projects beyond the gametophyte, a second leaf
is formed and a second root. Meanwhile, there is tissue differen-
tiation; the vascular elements of the leaf, stem, and root are

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 91

distinct, and the air-channels (only two in the first leaves) are
produced.

After development of sterile leaves for a few seasons, the
sporophyte begins to produce sporangia, as previously noted.

Apogamy has been reported by only one worker, Goebel (’97),
who found examples in J. lacustris L. and I. echinospora Dur.
where the tiny leaf-producing shoots eventually giving rise to
roots replaced sporangia in position. These plantlets became
independent by the decay of the old leaf tissue.

BIBLIOGRAPHY FOR MORPHOLOGY

Belajeff, W. (’85). Die Antheridien und Spermatozoiden der heterosporen
Lyecopodiaceen. Bot. Zeit. 43:793. 1885.

Bower, F. O. (’08). The origin of a land flora. London, 1908.

Braun, A. (’64). Ueber die Isoetes—Arten der Insel Sardinien, nebst allgemeinen
Bemerkungen iiber die Gattung Isoetes. K. Akad. Wiss. Berlin, Monatsber.
1863: 554-624. 1864.

Bruchmann, H. (’74). Wurzeln von Isoetes und Lycopodium. Jenaische
Zeitschr. f. Naturwiss. 8:522. 1874.

Campbell, D. H. (’91). Contributions to the life history of Isoetes. Ann. Bot.
5 :231-256. pl. 15-17. 1891.

Cesati & DeNotaris. (’58). Ind. Sem. Hort. Reg. Bot. Gen. 1858.

Farmer, J. B. (’89). On Isoetes lacustris. Roy. Soc. London, Proc. 45 B:306.

1889
,» (790). Morphology of Isoetes lacustris. Ann. Bot. 5:37-62. pl. 5-6.
1890.
Goebel, K. (’97). Ueber Sprossbildung auf Isoetes blattern. Bot. Zeit. 37:1-6.
f. 1-4. 1897.

Hegelmaier, F. (’72). Zur Morphologie der Gattung Lycopodium. Bot. Zeit.
30:773-779. 1872.

Hofmeister, (’62). The higher eryptogamia. Ray Soc. 1862.

Russow, E. (’72). Vergleichende Untersuchungen betreffend der Histologie der
vegetativen und Sporen-bildenen Organe. Acad. Sci. St. Petersbourg, Mem.
Wie ist) PSz2.

Scott, A. H., and Hill, G. T. (’00). Structure of Isoetes hystrix. Ann. Bot. 14:
413-454. 1900.

Smith, R. Wilson (’00). The structure and development of the sporophylls and
sporangia of Isoetes. Bot. Gaz. 29: 225-258, 324-340. pl. 138-20. 1900.

Stokey, A. G. (709). Anatomy of Isoetes. Bot. Gaz. 47: 311-335. pl. 19-21. 1909.

West, C., and Takeda, H. (715). On Isoétes japonica A. Br. Linn. Soe.
London, Trans. Bot. II. 8:333-376. pl. 33-40. f. 1-20. 1915.

EcoLocicaL RELATIONS OF THE GENUS ISOETES

The genus /soetes presents interesting ecological and geo-
graphical relations. The species prove very diverse in habitat,
ranging from lacustrine forms submerged in five or more feet of
water, to those strikingly xerophytic, exposed on dry hillsides.
Structural characters appear unusually constant, save in minor
points. Plants are perennial, and in some cases seem able to
withstand desiccation over long intervals, appearing after one or

[Vol. 9
92 ANNALS OF THE MISSOURI BOTANICAL GARDEN

more dry seasons. Still others grow where alternately submerged
and exposed during each growing season.

Ecologically, therefore, it is convenient to subdivide the group
into (1) submersed, (2) amphibious, and (8) terrestrial forms,
though this does not represent systematic relations.

The geographic range of the individual species is usually lim-
ited, but representatives of the genus are found in practically
all explored countries. In Europe, France leads with five species;
in Africa, Algeria with four species and one variety. In North
America, Massachusetts with five species has probably more re-
corded stations than any other state. California has six species
recorded, one of which is truly terrestrial. At present, it is
difficult to determine centers of distribution, but the accumula-
tion of more data should help in ascertaining relations.

By means of a tabular survey of some North American species,
one can gain an idea of the range of species relations in the matter
of habitat, plant associates, structural diversity, etc. In every
subdivision, one can find examples from different regions of the
world. North American forms, particularly those of a somewhat
extended range, are chosen simply because of more available
data.

It may be noticed that all submersed or amphibious forms
are related to fresh water. The original account of a salt-water
relation for J. maritima has since been corrected. The ter-
restrial forms, J. melanopoda and I. Butleri, are found in so-called
“alkali flats” where the content of magnesium and sodium sul-
phates is high. These flats are very level, and so become very
wet in the spring but are very dry in summer, for the clay or hard
pan is covered by too thin a soil layer to hold moisture (E. Hall).

In other regards there is much diversity in habitat relations.
Most of the submersed forms are related to lakes or ponds, vary-
ing from a few inches to six or more feet in depth. Of the am-
phibious forms, some are riparian, notably I. riparia and I.
saccharata, but most are found in pools or ponds, where they
form a marginal zone, thus becoming exposed in the usual
seasonal lowering of the water level. These ponds or lakes may
be in meadows, woodland, or as in the case of J. melanospora, —
may be merely low depressions in granite rock, which contain a
few inches of soil and which in summer retain no water, leaving
the plants to be parched and dried by full exposure to the sun.

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1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 95

Such plants as this might be considered as grading readily into
the more distinctly terrestrial forms. Of these transitional forms,
some start growth in very moist habitats, fruit as the season
progresses, and die down except for the corm, during the very
dry intervals of late July and August. Such plants as these
could not have come into consideration when the name “Isoetes,
equal at all seasons” was applied. In our country, J. Orcuttu of
southern California appears “in level pastured meadowland,
growing scattered in grassy sod, especially in low places, but
never in places where water stands or has stood. The leaves so
nearly resemble surrrounding grass in size and color that the
plant can scarcely be found except by lifting sod and tearing it
apart.” In some ways it seems comparable to the Algerian forms,
I. histriz and I. Duriaei, which grow in exposed places, the latter
with xerophytic grasses in crevices on granitic mountain slopes.

Plant Associates—Data in regard to the plants occurring with
Isoetes are not available in many cases. The table shows what
has come to notice in this regard, in some American species.
Frequently it would seem that Jsoetes has few competitors where
it succeeds in holding its own. On the the other hand, it may be
so thoroughly mixed with grasses, sedges, and other forms of a
like habit, that it is easily overlooked.

Physiological and Structural Relations—In the matter of
structural characters, there is an unusual uniformity throughout
the group, regardless of environment. All display a corm of two or
three lobes, in which reserve material is deposited. In some cases,
the corm endures drought for one or more seasons and, with
return of moisture, again becomes active. The corm rarely
branches, and hence there is no vegetative spread by this method.
There is great diversity in number and size of leaves; and though
this appears to have no invariable relation to the habitat, smaller
forms frequently occur in the terrestrial group. There is a gen-
eral plan of structure in the leaves which includes four lon-
gitudinal air spaces, separated by septa, and surrounded by a
peripheral wall of green tissue. There is a tendency for greater
development of the air-spaces, with relatively fewer layers (as
low as two) of green tissue and narrower septa in the submersed
forms. Species in dry situations show less surface development.
The leaves are usually narrower with small lacunae, walled by

[Vol. 9
96 ANNALS OF THE MISSOURI BOTANICAL GARDEN

several layers of compact tissue and separated by as many as
five to seven layers in the partitions.

In terrestrial forms, the bases of the leaves often prove per-
sistent. Sometimes they remain as simple brown papery scales,
but in their most striking forms they become horny, with ex-
tended spines, marginal and central, as in J. histriz.

The leaf shows variation in two other directions, in the dis-
tribution of groups of mechanical cells in the peripheral region
and in presence of stomata. The former may be entirely lacking,
as usually occurs in submersed forms, and sometimes in am-
phibious. With exposure to air, there is development of these
groups of supporting cells, often to the number of four, sometimes
six, chief aggregations, which are accompanied by smaller ones
on occasion. The degree of development. of such: accessory
groups varies greatly. Frequently the upper, more exposed region
shows more of these groups of cells.

In the case of stomata, there is no uniformity within the sub-
mersed group. Jsoetes echinospora and a close ally, J. Brauniu
of America, both submersed, show striking dissimilarity in this
regard. The former has no stomata, the latter always some.
Other species may show even more. In the amphibious and
terrestrial forms, it is obvious that there will always be more or
less development in the regions exposed to air.

A third leaf feature, the velum, which covers the basal spor-
angium, has attracted more or less attention. It is included here
for that reason, rather than because of any definite correlation
with ecological features. The range from very narrow to com-
plete veils seems to be run in each group.

Very little attention has been paid to root systems, which are
in all cases fibrous, as a result of dichotomous branching.

Seasonal Relations.—All species of Isoetes appear perennial,
with a longer or shorter growing season. Submersed forms are
reputed to be green during a longer period, as a rule, and usu-
ally fruit late, as August to October. A few amphibious forms
fruit in the spring, and then die down during the summer, some-
times to become green again in fine fall weather. Engelmann
traced through the seasons the activity of Isoetes Engelmanni,
a vigorous amphibious form, which continues active throughout
the summer and fall season, producing spores for a relatively long
period. /. Malinverniana of the aqueducts of Piedmont, Italy,

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 97

is reported as fruiting throughout the summer. Most forms are
more restricted, as, for instance, J. melanopoda in May and early
June, or I. riparia in August and September.

After spore production, there is a more or less rapid develop-
ment of the alternating generation, as shown by Engelmann in
his cultures. The sporeling stage then appears in a short inter-
val after spore production, a point demonstrated as early as 1828
by Delile in his careful observations on Jsoetes setacea. Spore-
lings produce a small group of leaves which are sterile. Fruiting
structures appear only in the second or subsequent seasons.

Geographic Distribution.—It is the experience of collectors
that the distribution of Isoetes species is remarkably restricted,
though there are representatives in most parts of the world.

In North America there is a striking exception to this in J.
Brauni Dur., a form found both on the east and west coasts,
and in much of the territory between these. Maine and Massa-
chusetts are perhaps richest in the number of stations reported,
but the form is common in eastern Canada, in the northeastern
United States, and is reported less frequently in Ohio, Indiana,
Michigan, Wisconsin, and Minnesota. There then appears a
zonsiderable gap in the continuity, with the western represen-
tatives appearing only as far as Utah, and then westward up the
coast.

I. macrospora Dur. and I. Engelmanni A. Br. possibly repre-
sent the forms next most widely distributed. The former is
northern, like 7. Brauni, and is found in eastern Canada, and the
northern United States as far west as Minnesota. I. Engelmanni
is of slightly more southerly occurrence, and is found from New
England, west to the Mississippi Valley, with Engelmann’s own
station at St. Louis as the farthest west.

More restricted in character are the following species of the
eastern border: J. Tuckermani, I. riparia, I. saccharata, I. Eaton,
and J. foveolata. Farther south, in Georgia and Florida, occur
I. flaccida and its variety alata, while I. melanospora is endemic
in one station, Georgia, and J. lithophila in Texas.

In the central states, besides J. Engelmanni, the form I. me-
lanopoda Gay & Dur. proves of rather extended range in Illinois,
Missouri, Nebraska, Iowa, Oklahoma, and Texas. Its companion
form, I. Butleri, occurs in the western part of this range in even
drier localities.

[Vol. 9
98 ANNALS OF THE MISSOURI BOTANICAL GARDEN

The west coast of the continent boasts of eight distinctive
species and three varieties. Of these, four species are especially
northern in character, occurring in Washington or farther north,
i.e, I. Piperi, J. Flettu, I. occidentalis, I. truncata. Four are
either more extended to the south, as J. Nuttallu, I. Howellu, and
I. Bolanderi, or restricted to southern California, as J. Orcuttiv.

This last species even extends into Lower California, and
therefore, with J. mexicana and J. Pringlei, represents the genus
in Mexico.

The West Indies yield two endemic forms, J. cubana (Cuba)
and I. Tuerckheimu (Haiti).

Of the South American forms, three are reported for Brazil,
I. amazonica, I. Gardneriana, and I. Martu. Three others, less
known in collections, occur in more remote stations, J. Lechlert
(Argentine), I. triquetra (Peru), and J. Savatiert (Patagonia).

The situation in Europe is somewhat parallel to that in North
America in that two species have a rather wide range in the
northern territory. J. lacustris and I. echinospora are found in
the British Isles and on the continent in the northern countries.
Aside from these, there are eight other forms on the continent
more local in distribution, and three in Mediterranean islands.
In France, we find J. setacea, I. Boryana, I. tenuissima, I. histrix,
and I. Brochoni; in Italy, the giant J. Malinverniana; in Greece,
I. Heldreichu, and in Spain, J. baetica (probably not a valid
species). In the Mediterranean islands, Corsica, Sardinia, or
Sicily, are reported J. dubia, I. velata, and I. tegulensis. I.
azorica is reported only from the Azores.

To date, the genus appears much more sparse in Asia, with
I. olympica for Asia Minor, I coromandelina for India, and I.
echinospora var. asiatica and I. japonica for Japan.

In Africa, Algeria shows especially marked abundance of forms
in that J. histrix, I. Duriaei, I. adspersa, I. velata and its variety,
Perralderiana, all occur here. Farther south, J. nigritiana has
been reported for the River Niger, and I. Schweinfurthii in the
Anglo-Egyptian Sudan. In southern Africa, Angola gives us J.
Welwitschu and I. aequinoctialis. I. Wormaldii and the little-
known J. natalensis, which may prove a valid species, are forms
from the Cape.

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 99

Oceanica proves very rich in forms, with three each in Aus-
tralia (I. Drummondit, I. Muelleri, and I. tripus) and Tasmania
(UI. Gunnii, I. elatior, and I. 4umilior), and two allies in New
Zealand (J. alpina and I. Kirki).

Floristic Relations—Some of the Mediterranean forms, as J.
velata, adspersa, Boryana, tegulensis, and tenuissima and I.
velata Perralderiana, show a very close relation as though orig-
inating from a single stock, which may be referred to as the Eur-
African stock. No other morphological group as large as this
is found in so limited a geographical region. The two New
Zealand species, J. alpina and J. Kirkiw, show evident relations
to each other. But associated morphologically with these eight
forms are many others in widely distant stations, as J. cubana of
Cuba, I. Schweinfurthui of Central Africa, 7. Orcuttu of southern
California. Obviously it is impossible to determine any basic
forms here.

In what might be termed the Echinatae group, one finds many
reports of I. echinospora itself in Europe, the closely related J.
Braunii in our northern territory (the two probably bridge the
Atlantic Ocean in the Arctic islands), and a variety in Japan
which presents a difficulty in the attempt to ascertain to which
it is the more closely related. There are representatives of this
group also along the west coast of North America, up to Alaska.
Obviously there is a more or less continuous northern band about
a large part of the known territory. Discontinuity may be due
to lack of present forms or to lack of knowledge of such forms.

The other morphological groups show rather a similar situa-
tion to the first-mentioned group, with representatives scattered
in north, south, east and west hemispheres.

It may be noted that the distribution of diverse species, of a
remarkably conservative genus, is striking in the number of in-
sular and coastal region forms which appear.

MATERIAL EXAMINED

The present monograph was suggested to the writer by Dr.
J. M. Greenman, under whose guidance the work has come to
completion at the Herbarium of the Missouri Botanical Garden.
To him especial thanks are due for encouragement, suggestion,
and advice in the progress of the problem. The writer is indebted

[Vol. 9
100 ANNALS OF THE MISSOURI BOTANICAL GARDEN

to the Garden for the use of the excellent collections of [soetes,
comprising the collections of two students of the group, Dr.
George Engelmann and A. A. Eaton, for the use of the original
notes of these workers, and for grants which made it possible to
pursue this work. It is also a pleasure to acknowledge the kind-
ness of Dr. Wm. R. Maxon, who placed the material of the
United States National Herbarium at the writer’s disposal; of
Dr. Aven Nelson and Dr. C. O. Rosendahl, who loaned the
material from the herbaria of the University of Wyoming and
the University of Minnesota, respectively; of Prof. L. R. Abrams,
who supplied some west-coast forms from the Dudley Herbarium
of Leland Stanford University; of Dr. 8. Schénland of South
Africa, Dr. D. A. Herbert and Prof. T. G. 8. Osborn of Australia,
Mr. L. Rodway of Tasmania, and Dr. W. 8. Dudgeon of India,
for material of exotic species.

The writer has also enjoyed the privilege of examining the
sheets of Jsoetes in the Gray Herbarium, in the Herbarium of
the New York Botanical Garden, and in the Field Museum of
Chicago. To those in charge who have facilitated this work, she
desires to express her appreciation of the privileges enjoyed and
the courtesies extended.

In 'the matter of photographic illustrations, the writer is
especially grateful for the suggestions and aid given by Dr. J.
W. G. Land of the University of Chicago.

To all others who have by contributions of material, by sug-
gestion, or other evidence of interest, added to the completeness
of this paper, the writer expresses sincere gratitude.

RELATIONSHIPS IN GENUS

The species of Jsoetes might be considered from the point of
view of the sculpture of the megaspore wall as representing a
long series from those with simple distinct prominences to those
with extended ridges or crests, finally becoming reticulate. In
this long series many forms stand out distinctly. But with
abundance of material there is) often much evidence of inter-
grading between adjacent forms and even of variation within
the same species. As an example of the latter, one might cite the
case of J. Bolanderi of the west coast of America, a form or-
dinarily adorned with low tubercles, which on occasion fail to

1922]
PFEIFFER—MONOGRAPH OF THE ISOETACEAE 101

appear, leaving a smooth surface. As illustration of intergrading
between closely related forms, the J. velata complex of the Med-
iterranean region serves well. Here one must use all the avail-
able distinctions to hold the forms apart; yet, were these not
used, the result would be simply a complex, incapable of treat-
ment as a unit. Examples of pairs of species in which the same
difficulty arises are J. riparia and I. saccharata, I. macrospora
and J. Tuckermani, I. echinospora and I. Brauni. In all these
cases, absolute separation on spore characters alone would be a
difficult task; other features, even geographical range, may prove
invaluable as supplementary points.

In all instances, it has been the aim of the writer to so treat
the forms as to avoid points of an insignificant nature and to
emphasize what seemed more important features. Only fairly
definite varieties have been maintained. In some cases, it has
been necessary to reduce long-recognized varieties and forms,
in others those of more recent standing. Possibly this has oc-
curred more frequently than usual in a work of this sort. The
most obvious explanation for this is related to the relatively
rare occurrence of the genus in the experience of most workers.
The result of this is the seeming distinctiveness of any single
collection made. One other possible result of inexperience is
description based on immature material. Many collections of
under-ripe plants are made without realization of the absolute
necessity of mature characteristics for positive determination.

It is furthermore not always easy to determine from collections,
sometimes scant in amount and accompanied by few or no
habitat notes, to exactly what extent ecological factors have re-
sulted in variations. The writer is inclined to believe that such
variations have at times been the basis for described varieties
and has attempted in this work to avoid as far as possible clas-
sification of varieties and forms resulting from such factors as
the relative dryness of the season.

SPECIES NoT EXAMINED

Isoetes as a genus is distributed widely over the earth in very
local fashion, frequently in remote and inaccessible stations. In
such a group, it is not surprising that some forms have been
collected only once, nor is it unexpected that representation

[Vol. 9
102 ANNALS OF THE MISSOURI BOTANICAL GARDEN

should be lacking in America of some of these less well-known
forms. In spite of efforts extending over a considerable interval
of time, it has not been possible to obtain adequate material of
the following described species: J. Welwitschu, aequinoctialis,
Heldreichii, ngritiana, dubia, olympica, Gardneriana, elatior,
Muelleri, humilior, triquetra, echinospora var. asiatica, tripus,
Savatiert, neoguiniense, baetica, natalensis.

Wherever possible these species have been placed in the keys
according to the characters found in the literature. The species
descriptions are based either entirely on the original description,
directly quoted or translated, or on that plus supplementary
material in later accounts. It has been a matter of concern to
choose what seemed authentic. Unfortunately, the monograph
of Motelay and Vendryés, which should be of great aid here, has
so many typographical errors that one lacks confidence in its
reliability.

Krys

In the preparation of keys, the attempt has been made to use
as evident characters as possible, such as plant size, character of
leaf, and similar features. Unfortunately such points are depen-
dent to some extent on external conditions which may prove
variable. An effort has been made to take such variations into
account; obviously, some errors in judgment, especially because
of the use of dried material apart from its habitat, will occur,
which in some degree render the key inaccurate. Measurements
might better, therefore, be interpreted as suggestive of the prob-
able range rather than as absolute limits.

Furthermore, it has been necessary to utilize minute characters,
some of which are not readily determined, particularly in dried
material. Previous investigators, as Braun and Engelmann,
have stressed this point adequately. The latter further empha-
sized the skill that even the amateur can develop with the op-
portunity to study fresh material of several forms, so that stan-
dards of comparison may be developed. A little more care is re-
quired with the use of dried plants, which involves soaking and
more careful methods in dissecting and sectioning.

Again, with these minute characters, such as ligule and degree
of velum development, it is very difficult to more than approx-
imate an accurate description. In regard to such a feature as

1922]
PFEIFFER—MONOGRAPH OF THE ISOETACEAE 103

spore sculpture words prove at times a difficult mode of con-
veying an exact picture of the various markings. Recourse has
therefore been had to photographs, which will serve to counter-
act the shortcomings of verbal description.

In the case of microspore markings, the point should be borne
in mind that in such tiny structures the degree of magnification
plays an unusually large role. This is true in much smaller de-
gree of the megaspores. The description for microspores has
been based on what may be seen with a magnification approx-
imating 100 diameters, that for megaspores, about 50 to 60 diam-
eters.

IsoETACEAE Reichb.

Isoetaceae Reichb. H. G. L. Consp. Reg. Veg. 43.” 1828;
Dumortier, Anal. Fam. Pl. 68. 1829; Bartling, Ord. Nat. Pl.
13-14. 1830; Endl. Gen. Pl. 68-69. 1838-40; Schnizlein, Icon.
Fam. Nat. Reg. Veg. 85 . 1843-46; Ledeb. Fl. Rossica 4: 495.
1853; Underwood, Our Native Ferns & Fern Allies, 121. 1882:
Boissier, Fl. Orient. 5: 746. 1882; Kuhn in Martius, Fl. Brasil.
1’: 646. 1884; Luerrsen, Farnpfl. Deutschl. 845. 1889; Kuntze,
Rey. Gen. Pl. 2: 828. 1891-93; Ascherson & Graebner, Syn. Mit-
teleur. Fl. 1: 163. 1896-98; Sadebeck in Engl. & Prantl, Nat.
Pflanzenfam. 1*: 756. 1901-02; Small, Fl. Southeastern U. oie
ed. 1, 24. 1903, and ed. 2,30. 1913; Clute, Fern Allies, 207. 1905;
Piper, Contr. U. 8. Nat. Herb. 11: 88. 1906; Eaton in Gray,
Man. Bot., ed. 7, 58. 1908; Coulter & Nelson, Bot. Rocky Mts.
24,1909; Underwood in Britton & Brown, Ill. FL, ed. 1, 45. 1896;
Maxon in Britton & Brown, IIl. Fl, ed. 2, 50. 1913; Rydb. FI.
Rocky Mts. 1053. 1917.

Aquatic to terrestrial herbs with a short unbranched, lobed,
subterranean axis producing many dichotomous roots and erass-
like leaves, the enlarged bases of which contain solitary, sessile,
adaxial sporangia, more or less covered by a thin extension of
tissue or velum. Sporangia of two sorts, producing large tet-
rahedral megaspores and minute powdery microspores, respec-
tively. .

ISOETES L.
Isoetes L. Sp. Pl. 1100. 1753; Gen. Pl. 486, gen. no. 1048.

1754; Amoen. Acad. 3:25, gen. no. 1109. 1756; Syst. Nat., ed.
10, 1330, gen. no. 1048. 1759; ed. 12, 697, gen. no. 1184. 1767; ed.

(Vol. 9
104 ANNALS OF THE MISSOURI BOTANICAL GARDEN

13, 1284, 13822, gen. no. 1184. 1791; Syst. Veg., ed. 13, 792, gen.
no. 1184. 1774; Sadebeck in Engl. & Prantl, Nat. Pflanzenfam.
1*: 756. 1901-02.

Marsilea L. Fl. Suec. 996. 1745.

Calamaria Dillen. Hist. Muse. 541. pl. 80. fig. 2.1741; Kuntze,
Rey. Gen. Pl. 2: 828. 1891-93; Post & Kuntze, Lexicon, 88.
1904.

Subularia Ray, Syn. Meth. Stirp. Brit. 283. 1696.

Cephaloceratodon Genn. Comment. Critt. Ital. [1] no. 2: 111.
1861.

Tsoetella Genn. Comment. Critt. Ital. [1] no. 2: 114. 1861.

Perennials, submerged, amphibious, or terrestrial, with a 2-or
3-lobed, short fleshy axis or corm giving rise to numerous
branched roots and to a rosette of elongated, somewhat triangular
or quadrangular leaves. Leaves with 4 transversely septate,
longitudinal air-channels, with central fibro-vascular bundle;
peripheral groups of supporting cells present or absent, stomata
present or absent. Ligule a small, delicate, triangular exten-
sion of tissue on inner face of leaf above the sporangium. Spo-
rangium solitary, sessile, on adaxial side of leaf, contained within
a basal cavity, and more or less covered by a membranous tissue,
the velum, on the inner leaf face. Sporangia of two types, micro-
sporangia and megasporangia, bearing respectively microspores
and megaspores, which on germination develop gametophytes,
the former with a single antheridium, the latter with archegonia.
Megaspores hemispherical at base, with equatorial ridge, and
three other crests joined at apex, with variously sculptured walls.
Microspores minute, powdery, usually oval.

Type species J. lacustris L. Sp. Pl. 1100. 1758.

KeEy TO SECTIONS

A. Surface of megaspores chiefly tuberculate or spiny.
a. Megaspores tuberculate ~-------------------------- §1. Tuberculatae
b. Megaspores spiny -------------------------------- §2. Echinatae
B. Surface of megaspores irregularly crested or reticulate.
a. Megaspores irregularly crested -------~------------- §3. Cristatae
b. Megaspores reticulate, at least on basal face ----.---§4. Reticulatae

Srecr. 1. TUBERCULATAE

§ 1. TuBERCULATAE. Forms with 2 or 3-lobed corms; mega-
spores rarely smooth, usually marked with few or many large
warts or many small tubercles, chiefly simple.

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 105

Key To SPECIES

A. Forms with 3-lobed corms; megaspores marked with few to many large
rounded tubercles; microspores rough; leaves mostly slender, usually
with peripheral strands and stomata. Chiefly forms of the eastern hemis-
phere.

a. Velum none or little developed.

a. Terrestrial forms. aoe

f) Didavesiew. varuey metien = 22-8 eo Fee oe 1. I. Welwitschit

Il. Leaves many, velum covering 144-35 of sporangium. 2. I. aequinoctialis
B. Forms not terrestrial in habit.

I. Megaspores more than 400, in diameter.

1. Leaves few in number, less than 20.
*Stomata present.

tPeripheral strands well-developed -------__- 8. I. Schweinfurthii
ttPeripheral strands variable (none-6) ~-_--_______ 3.5. I. ovata
ALOT ba Seriya eer oe SR eee Yee 4. I. Heldreichii

2. Leaves more than 20 in number.
*Megaspores 480-540 » in diameter, with large

aes ecb gee et ee ea ee 5. I. coromandelina
**Megaspores 565-680 in diameter, with num-

prpue Vamps « banerclad, 25020 sete ea 6. I. setacea
***Megaspores 660-800, in diameter, with

elongated coarse processes ~-_--_-- wpe ee a 7. I. Matinverniana

II. Megaspores chiefly less than 400 » in diameter.

1. Leaves not filiform, more than 25 em. long __________ &. I. cubana
2. Leaves filiform, less than 25 em. long.

PIMPEBNGROR. Oreny A eho ke te SE 9. I. nigritiana
IRR EMVEOR WRAL. aioe eee La eS 10. I. adspersa

b. Velum complete or nearly so,
a Megaspores with few coarse warts.
I. Megaspores becoming dark when wet.
1. Coarse plants, more than 15 leaves, more

SEU ne NETS Tg | apse eh a Se 11. I. Boryana
2, Finer plants, less than 15 leaves, less
analy be hemo i tenet hts 2622 oe i ay pees, 12. I. tenuissima

II. Megaspores creamy when wet.
1. Leaves chiefly less than 24 em. in length.
*Leaves slender and short.
tLeaves more than 10 em. long.
o Megaspores more than 480 y in diameter ______ 18. I. dubia
oc Megaspores less than 480, in diameter --15a. JI. velata var.
Perralderiana
tieaves; less “ian 5) em. lonis' 2 oe pa 14. I. olympica
**Leaves coarser, chiefly less than 24 em. in length,
WOPey Maer oS aa i ee 15. I. velata
2. Leaves longer, chiefly more than 22 em. in length__16. I. tegulensis
8. Megaspores with more numerous regular tubercles.
I. Leaves more than 15 em. long, more than 10 in number __17. JI. alpina
II. Leaves less than 15 em. long, less than 10 in number __18. I. Kirkii

B. Forms with 2- or 3-lobed corms; megaspores rarely smooth,
usually marked with numerous small tubercles, sometimes
confluent; microspores smooth or rough; peripheral strands
and stomata variable among species.

a. Corms 3-lobed.
a. Velum none or little developed.
I, Leaves short, less than 11 em. in length.

ERS) ACL G04 5 | an a es eR 19. I. Gunnii-
2. Stomata present.
*Megaspores less than 470» in diameter ________ 20. I. Drummondii

**Megaspores more than 420 y in diameter ________ 21. I. amazonica

[Vol. 9
106 ANNALS OF THE MISSOURI BOTANICAL GARDEN

II. Leaves long, more than 20 em. in length.

1. Peripheral strands and stomata present -----~~-- 22. I. Gardneriana
2. Peripheral strands and stomata absent ~------------ 23, I. elatior
Bp. Velum complete.
I. Amphibious; leaves 7 em. long ~-----------------~--- 24, I. Muelleri
II. Terrestrial,
1. Leaf—bases persistent, conspicuous, usually spiny ----25. I. histria

2. lLeaf-bases sometimes persistent, not conspicuous.
*Leaves more than 13 in number, longer than 8 cm. --26. I. Nuttallit
**Leaves less than 15 in number, less than 8 em. ------ 27. I. Orcuttu

b. Corms 2-lobed.
a. Velum complete.
I. Megaspores dark when wet, small-tuberculate.

1. Megaspores large, more than 600» in diameter ----28. I. hwmilior

2. Megaspores small, less than 480, in diameter,
*Leaves less than 7 em. long; megaspores more

Phan VSG 0VuNwae eee oe SET eae Pe Pes 29. I. melanospora
**Teaves more than 7 em. long; megaspores less
(iD OEeN aN aH GAO) py ech ee ee ee 80. I. lithophila

II. Megaspores white or creamy.
1. Megaspores marked with large warts.
PONV isch Stall vy elsy Si), SNA LC) eee eee ree eee ee ee 81. I. flaccida
**Warts confluent into bold ridges on the basal face _-31a. I. flavcida
var. alata.
2. Megaspores marked with very low tubercles.
*@iLoM aia PTOSeUL Wis oot cm ee ela ee ene 82. I. Lechlert
PES Coretta lel cera poy sa hye eee ee eee ere 33. I. triquetra
B. Velum narrow, usually covering not more than one-
third of sporangium.
I. Megaspores with tubercles frequently confluent into wrinkles.
1. Amphibious; stomata and peripheral strands usually
evident.
*Megaspores more than 4204 in diameter ~--------- 84, I. Howell
**Megaspores less than 420 in diameter ~--------- 34a, I. Howellit
var. minima
2. Submerged; stomata few, peripheral strands lacking,
*Leaves more than 6 cm. long, slender --__-____--_-- 85. I. Bolandert
**Teaves less than 6 cm. long, stout -_____-_------- 35a. I. Bolanderi
var. pygmaea
II. Megaspores with chiefly simple tubercles.
ie eeripheral strands) lacking j= 222-2 2= es amos 36. I. Tuerckheimi
2. Peripheral strands present.
*Megaspores less than 480 w in diameter.
tSurface of spore smooth or with large simple

Gul ereless) a ae eS Be ee eee 37. I. mexicana
ttSurface of spore with small tubercles, sometimes

(Kopi bisreh meee Muy ERLE NG po as a A ale, Se ete 88. I. melanopoda

**Megaspores more than 480, in diameter ------------ 39. I. Butleri

1. Isoetes Welwitschii A. Br. in Kuhn, Fil. Afr. 196. 1868;
A. Br. Sitzb. Naturf. Fr. Berlin, 7. 1867; Motelay & Vendryées,
Actes Soe. Linn. Bord. 36: 388. 1888.

Calamaria Welwitschii Kuntze, Rev. Gen. Pl. 2: 828. 1891-93.

Corm 3-lobed; leaves 6-15, rigid, straight or slightly curved,
firm, very fine, pale green surrounded at base by some dark
scales; stomata numerous; peripheral strands 4 primary, acces-
sories none in front, 4 on each side in back; velum very narrow,

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 107

almost none; ligule elongated, little shorter than the sporangium;
megaspores 300-360 uy and 480-540 yp, dimorphous in same spo-
rangium, ashy when dry, with white markings; warts prominently
numerous on the basal face, larger and smaller intermixed, on
apical faces all small, very numerous; microspores 30 u long, 20 u
wide, somewhat acute, with scattered minute inconspicuous
tubercles.

Distribution: Huilla, District of Angola, Africa.
No authentic specimens seen.

2. I. aequinoctialis Welw. in Kuhn, Fil. Afr. 195. 1868; A. Br.
Sitzb. Naturf. Fr. Berlin, 7. 1867; Motel. & Vendr. Actes Soc.
Linn. Bord. 36: 365. 1883.

Calamaria aequinoctialis Kuntze, Rev. Gen. Pl. 2: 828. 1891-
93.

Corm 3-lobed; leaves numerous, 30-40 em. long, rigid, firm;
stomata numerous; peripheral strands 4 primary and 18-24
weaker accessory; ligule elongate triangular, shorter than spo-
rangium; velum incomplete, covering 14-34 of the sporangium;
sporangium globose; megaspores dimorphous, 380-480 u and 550-
620 uy in diameter, cinereous, ornamented by white commissural
ridges and warts; warts coarse, hemispherical, distant, some-
times doubly confluent, 5-6 on apical faces, solitary or few con-
fluent in smaller megaspores; microspores 30-40 » long, 25-35 pu
thick, strongly obtuse, densely spiny. Description compiled.

Distribution: Angola, in wet prairies of Pungo Andago,
8-1200 m. altitude.

3. I. Schweinfurthii A. Br. in Baker, Jour. Bot. 18: 108. 1880;
Motel. & Vendr. Actes Soe. Linn. Bord. 36: 380. 1883.

Calamaria Schweinfurthii Kuntze, Rev. Gen. Pl. 2: 828. 1891-
93.

Corm 38-lobed; leaves 9-25, 25-32 em. long, firm, gradually
tapering to an acute apex, with membranous margin developed
1-3 em. above level of sporangium; stomata common; periph-
eral strands 4 (or 6) cardinal, strongly developed, plus 6-8 ac-
cessory groups; ligule short, broad triangular; sporangium ovoid
to oblong, 4-6 mm. long, with velum none or exceedingly nar-

[Vol. 9
108 ANNALS OF THE MISSOURI BOTANICAL GARDEN

row; megaspores white, creamy when wet, 400-500 y in diameter,
with few large warts on apical faces, more numerous on basal;
microspores 27-82 in length, almost smooth.

Distribution: Central Africa, Kingdom Djur.

Specimen examined:

Africa: Anglo-Egyptian Sudan, Jur Ghattas, 7°N., under water,
June-July, 1869, Schweinfurth (Mo. Bot. Gard. Herb.).

The habit is much like that of J. Boryana Dur. except for longer
leaves which are commonly coarser than those of the forms
I. velata and its allies, tenuissima, tegulensis, etc., as well as I.
setacea Bose. It differs further from these forms in that the
velum is lacking, in contrast to being practically completely de-
veloped. The megaspores do not turn dark in moisture, as do
those of J. Boryana.

The species can be delimited from J. adspersa A. Br., which is
similar in lacking a velum, in that it has far coarser, as well as
longer, leaves, that the megaspores are larger (over 400 p rather
than with that ad a maximum), and that the microspores are
smooth rather than long spinulose.

Contrary to Baker’s and Motelay and Vendryées’ description,
I find the megaspores large tuberculate, with such markings that
they might easily be confused with J. Boryana Dur., I. tegulensis
Genn., J. tenuissima Bor., ete. I find no evidence of honeyeomb-
ing in my material, part of which is from the herbarium of Mo-
telay himself.

3.5 I. ovata Pfeiffer, n. sp.t

Corm 3-lobed; leaves 7-15, 6-24 em. long, slender, tapering
to apex, with basal membranaceous margins but briefly extended;
stomata present; peripheral strands lacking or six in number;
ligule deltoid, with broad base; sporangium small, ovoid, 2.5-4
mm. long, lacking a velum; megaspores cream-colored, 520-830 p
in diameter, with high well-rounded large tubercles, seldom be-
coming somewhat vermiform; commissural ridges decidedly

I. ovata sp. nov. Cormus trilobatus. Folia numero 7-15, longitudine 6-24 em.,
angusta, versus apicem attenuata, basi membranacea breviter dilatata, stomatibus
instructa et fibrosis periphericis vel nullis vel numero sex instructa. Lingula tri-
angularis, basi lata. Sporangium ovatum, parvulum, longitudine 2.5-4 mm., sine
velo. Macrosporae gilvae, diam. 520-830 ,, tuberculis crassis prominulis, raro ali-

quantulum verruculosis ornatae, costis commissuris teretibus, aliquando decussa-
tim rugosis. Microsporae longitudine 31-36 », leviter reticulatae.

1922]
PFEIFFER—MONOGRAPH OF THE ISOETACEAE 109

rounded, and occasionally cross-wrinkled; microspores fawn-

colored, 31-86 p, lightly reticulate, with ridges spine-like in sil-

houette.
Distribution: British Guiana.
Specimens examined:

British Guiana: pools by shore of Mazaruni River, Demerara,
December, 1890, Jenman (N. Y. Bot. Gard. Herb.), rypr;
Baracarra, Mazaruni River, Demerara, December, 1890, Jen-
man (N. Y. Bot. Gard. Herb.).

4. I. Heldreichii Wettst. Verh. K. K. Zool.-Bot. Ges. Wien
36: 239-240. pl. 8. 1886, whence the following description:
Corm 3-lobed, 3-6 mm. long, 3-7 mm. broad; leaves 3-8, fine,
flexuous, green, smooth, 10-25 cm. long; no peripheral strands
or rarely one dorsal; no stomata; ligule obovate-acute, very
finely and irregularly cut; sporangia 4-6 mm. long, without
velum; megaspores 14-86 in number, creamy white, globose, in-
conspicuously trigonous, about 660 u in diameter, warty [plate
shows 12 or so warts on one of upper faces]; microspores pow-
dery, elliptical, with narrow winged margin, and marked with
short spines.
Distribution: Greece, plains of Thessaly.
Specimen examined:
Greece: amphibious in wet places, schistose substratum, in lower
region of Pindus Mountains, alt. 3500’, 5 July, 1885, Held-
reich 899 (Gray Herb.).

5. I. coromandelina L. fil. Suppl. Pl. 447. 1781; A. Br.
Verh. Bot. Ver. Brandenb. 4: 327. 1862; Motel. & Vendr. Actes
Soe. Linn. Bord. 36: 380. pl. 16. fig. 7. 1888.

I. brachyglossa A. Br. Verh. Bot. Ver. Brandenb. 4: 327. 1862.

I. capsularis Griffith, not Roxb., in Posth. Papers, Cryptog.
Pl. 572-575. pl. 116-118. 1849.

Calamaria coromandelina Kuntze, Rev. Gen. Pl. 2: 828. 1891-
93.

Corm 3-lobed; leaves 20-60, large, with very wide membra-
nous wings at base, extending above sporangium level; stomata
numerous in upper region, lacking in basal portion of leaves;
peripheral strands present, 4 very strongly developed with sev-

[Vol. 9
110 ANNALS OF THE MISSOURI BOTANICAL GARDEN

eral weaker accessory; ligule conspicuous, very wide and short,
often appearing truncate in older leaves, but pointed in young;
sporangium large, maximum about 12 mm. in length and 9 mm.
in width; velum none; megaspores white when dry, gray when
moist, 480-540 u in diameter, somewhat flattened, marked with
numerous large tubercles, closely arranged and occasionally ex-
tended into very short rounded ridges; microspores red-brown
or paler at maturity, 26-33 yp, chiefly 30 u, smooth.

Distribution: India.

Specimens examined:

India: Madras, 1919, Fyson (Mo. Bot. Gard. Herb.) ; Peninsula
of India, without date, Royle (?) (Gray Herb.) ; “Peninsula
Ind. orientalis,’ Herb. Wight. Cryptogamia 4 (N. Y. Bot.
Gard. Herb.) ; near Seven Pagodas, Madras, February, 1922,
Kashyap (Mo. Bot. Gard. Herb.).

Dr. W. 8. Dudgeon, through whose courtesy material from
India was obtained, gives the assurance of local botanists that
there is but one species in India. The chief difference between
the descriptions of J. coromandelina and I. brachyglossa seems
to be one of leaf length, which would not be a character of speci-
fic rank.

The specimens examined were very large in the sporangium
region, reminding one of the giant J. Malinverniana of Europe.
All mature sporangia proved to bear megaspores. No published
record for microspores appears available in the literature con-
cerning either J. coromandelina or I. brachyglossa. The meas-
urements made as reported above were made from spores scat-
tered among the sporophylls, sometimes in small groups but in
all cases distinctly recognizable as Jsoetes microspores. Some
are unusually brilliant with orange-red coloring, possibly due to
chemicals.

6. I. setacea Bosc, “Dict. d’ Hist. Nat.’ in Delile, Mem. Mus.
Paris 14: 100-119. pl. 6-7. 1827; (Lamarck, Encycl. Meth. 3: 314.
1789.) (?); A. Br. Verh. Bot. Ver. Brandenb. 4:30. 1862; Ba-
ker, Fern Allies, 129. 1880, and Jour. Bot. 18: 106. 1882; Milde,
Fil. Eur. 286. 1867; Motel. & Vendr. Actes Soc. Linn. Bord.
36: 376. pl. 11. fig. 1-2. 1883.

Calamaria setacea Kuntze, Rev. Gen. Pl. 2: 828. 1891-93.

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 111

Corm 3-lobed; leaves 10-40 (rarely 60), 12-40 cm. long, light
green, firm but not stiff, tapering to apex, with wide membrana-
ceous margin at base gradually narrowed to disappearance 1-2
em. above sporangium level; stomata present in upper parts of
leaves; peripheral strands variable, but chiefly 6 plus accessory
strands; ligule longer than wide; sporangia 4-6 mm. long, lightly
marked with sclerenchyma cells; velum none; megaspores white,
564-680 u (rarely 800) in diameter, densely crowded on all faces
with small warts or tubercles; commissural ridges prominent and
wide; microspores 27-37 » long, usually with slightly crenulate
margins and with low crest.

Distribution: Montpellier, Herault, France.

Specimens examined:

France: Grammont, near Montpellier, December, 1820, Ballard
(Gray Herb.) ; Montpellier, ex Herb. Engelmann (Mo. Bot.
Gard. Herb.); mare de Grammont pres Montpellier, Delile
(N. Y. Bot. Gard. Herb.) ; lac de Grammont, August, 1837,
de Gerard (Mo. Bot. Gard. Herb.) ; Montpellier, Grammont,
21 March, 1840, Bubani (U. S. Nat. Herb.) ; Montpellier,
1842, Wanderley (Mo. Bot. Gard. Herb.); Montpellier,
Grammont, 30 June, 1842, without collector (Mo. Bot. Gard.
Herb.) ; pools of plateau of Roquehaute, 7 June, 1863, Durieu
21 (N. Y. Bot. Gard. Herb.) ; pond near Montpellier, 8 June,
1857, Cosson (Gray Herb., Mo. Bot. Gard. Herb., and N. Y.
Bot. Gard. Herb.) ; near Beziers (Herault), and Juire, 1879,
Gautier (N. Y. Bot. Gard. Herb.) ; Montpellier, 1866, Cosson
(Mo. Bot. Gard. Herb.); marsh, Roquehaute near Beziers
(Herault), 3 June, 1862, Cosson (Mo. Bot. Gard. Herb., N.
Y. Bot. Gard. Herb., and Gray Herb.); pool, Roquehaute,
June, 1862, Duriew (Mo. Bot. Gard. Herb.) ; “in almost all
the ponds of the volcanic plateau of Roquehaute, Herault,”
17 May, 1864, Motelay (Mo. Bot. Gard. Herb.); ponds of
Roquehaute, 11 May, 1864, Cheveneau (U.S. Nat. Herb.) ;
pond of Roquehaute near Beziers, June, 1869, Cheveneau
(Gray Herb.); near Montpellier, Grammont, 6 June, 1884,
without collector (U. S. Nat. Herb.); pond at Grammont
near Montpellier, November, 1876, Duval-Jouve (Gray
Herb.) ; Grammont near Montpellier, 10 May, 1888, Herb.
Fac. Scient. Monsp. (U.S. Nat. Herb.); Portiragnes
(Herault), ponds in plateau of Roquehaute, 1 April, 1888,

[Vol 9
112 ANNALS OF THE MISSOURI BOTANICAL GARDEN

Neyraut (Mo. Bot. Gard. Herb.); Montpellier, in pond of
the woods of Grammont, 16 June, 1889, Herb. Copineau (U.
S. Nat. Herb.); pond near Montpellier, 1892, de la Per-
raudiere (Mo. Bot. Gard. Herb.); ponds of Roquehaute,
Herault, 15 May, 1895, Mandon (Mo. Bot. Gard. Herb.) ;
Portiragnes, Roquehaute, 2 May, 1896, Sennen (Mo. Bot.
Gard. Herb.); Portiragnes, Herault, ponds in plateau of
Roquehaute, 6 November, 1897, Neyraut (Mo. Bot. Gard.
Herb.); plateau of Roquehaute, May, 1898, Herbarium
Normale, I. Dorfler, (Neyraut) 3698, (U. 8S. Nat. Herb.);
Montpellier, Herault, 20 February, 1898, Mandon (Univ.
Minn. Herb.); Portiragnes, 8 May, 1898, Neyraut (Mo.
Bot. Gard. Herb. and U.S. Nat. Herb.) ; Montpellier, in the
ponds of Grammont, 3 July, 1907, Societe Cenomane d’Ex-
siccata [Jean de Vichet] 482 (Mo. Bot. Gard. Herb.) ; Lae
de Grand Lieu, 27 September, 1880, without collector (Mo.
Bot. Gard. Herb.); without locality or date, DeCandolle
(N. Y. Bot. Gard. Herb.).

Historically one of the oldest species of Isoetes, I. setacea Bosc
was the subject of a detailed and interesting account by Delile,
who credited Bose with the name for this species of central
France, as published in Dictionnaire d'Histoire Naturelle. The
lack of velum associated with the numerous small tubercles of
the megaspore and the rather firm but flexuous, fine leaves, make
distinctive points of difference between this form and the J. velata
series (complete velum), J. adspersa A. Br. (large warts on
smaller spores), and 7. Malinverniana Genn. (larger tubercles
on larger spores in much coarser plant).

The distribution of peripheral strands is the most variable pos-
sible; most frequently there are six at the cardinal points, with
numerous other groups irregularly arranged beneath a much
thickened epidermal layer. Sometimes these groups are so nu-
merous as to make an almost continuous band. On the other
hand, the cardinal bundles may be very weak; or only four of
them may be developed; or, most extreme situation of all, there
may be no development of these thickened cells. The different
possible arrangements may be found in the same plant, where
the base of the leaf shows no peripheral strands and the apex
a fairly strong development. Doubtless there is a response to
external factors.

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 113

7. I. Malinverniana Cesat. & De Not. Ind. Sem. Hort. Reg.
Bot. Genuensis, 1858; Ann. Sci. Nat. Bot. 4: 381. 1859; Linnaea
30: 741. 1859-60; Baker, Jour. Bot. 18: 106. 1880; Motel. &
Vendr. Actes Soc. Linn. Bord. 36: 342. 1883.

Calamaria Malinverniana Kuntze, Rev. Gen. Pl. 2: 828. 1891-
93.

Corm 3-lobed; leaves 90-100, 30-80 cm. long, rich’ green,
prismatic, subulate, with narrow membranous margin little ex-
tended (0.5-1.0 cm.) above level of sporangium; stomata few;
peripheral strands 6; ligule lanceolate; sporangia oblong, 2-2.5
em. long; velum none; megaspores white when dry, ashy when
wet, 660-800 u in diameter, with long coarse processes (sometimes
80 u in length), rounded at tip, extending on all faces between
narrow commissural ridges wavy in outline, frequently with large
compound knob occurring on upper face in angle formed by
ridges; microspores 33-38 u (rarely 29 u) in length, spiny.

Distribution: Piedmont, in Italy.

Specimens examined:

Italy: in slow-flowmg water in aqueducts, “Greggio and Olden-
ico,’ Piedmont, fruiting all summer, through the fall, even
into winter, 1865, Cesati (Mo. Bot. Gard. Herb. and N. Y.
Bot. Gard. Herb.) ; near Oldenico, Piedmont, 3 May, 1863,
Ascherson (Mo. Bot. Gard. Herb., N. Y. Bot. Gard. Herb.,
and Gray Herb.); ditches about Vercelli, “note de Durieu
dans son herbier: recu vivant de M. Malinverni, le 25 Oc-
tobre, 1867,” Malinverni (Mo. Bot. Gard. Herb.) ; Piedmont,
prov. Novara, in fountains and aqueducts, submersed, float-
ing, throughout year, 1910, (Gola) Fiori & Béguinot 1606
(Gray Herb.); near Oldenico, Piedmont, 1859, Malinverni,
(N. Y. Bot. Gard. Herb.).

This species is the giant form of Europe in leaf number and
length. The size of its megaspores is equalled only by that of
I. Duriaet Bory, which, however, in other features is a much
smaller plant. The coarse, long processes, visible to the naked
eye, and the peculiar large grains, compounded as it were from
a number of warty prominences, are definitely characteristic of
this species.

8. I. cubanaEngelm. Trans. St. Louis Acad. Sci. 4: 389.
1882; Sauvalle, Fl. Cub. 203. 1873, name only; Baker, Jour. Bot.

[Vol 9
114 ANNALS OF THE MISSOURI BOTANICAL GARDEN

18: 110. 1880, and Fern Allies, 138. 1887; Motel. & Vendr.
Actes Soc. Linn. Bord. 36: 350. 1883.
Calamaria cubana Kuntze, Rev. Gen. Pl. 2: 828. 1891-93.
Corm 3-lobed; leaves 20-40, 15-40 cm. long, bright green, firm,
of medium fineness, gradually tapering to a point, with membra-
naceous margin extended 2-5 cm. above sporangium level; brown
papery scales sometimes produced from leaf bases; stomata rare,
chiefly near tips; peripheral strands 6; ligule short, broad tri-
angular; sporangium oval, 4-7 mm. long, with very narrow
velum; megaspores white, 290-400 » long, closely marked with
large round depressed tubercles on each face; microspores 26-30 u
long, tuberculate.
Distribution: western Cuba, Pinao del Rio.
Specimens examined:
Cuba: “in rivulets (on the bottom) of the pinewood, Western
Cuba, Pinao del Rio, 1866,” Wright 3912 (Mo. Bot. Gard.
Herb., Gray Herb., U.S. Nat. Herb., N. Y. Bot. Gard. Herb.).

This form resembles the J. velata series in having large tuber-
cles on the megaspores, which differ, however, in not being re-
stricted to a central group on the apical faces but in covering
practically the whole face; furthermore, the tubercles instead of
being wart-like and much-raised are depressed. Of the 3-lobed
forms, it resembles J. adspersa A. Br. in the small megaspores,
less than 400 p, and in the absence of a velum.

9. I. nigritiana A. Br. in Kuhn, Fil. Afr. 196. 1868; Motel.
& Vendr. Actes Soc. Linn. Bord. 36: 388. 1883.

Calamaria nigritiana Kuntze, Rev. Gen. Pl. 2: 828. 1891-93.

Corm 3-lobed; leaves 12-15, 14-18 cm. long, flexuous, very
fine, rigid, pale green, opaque, with numerous stomata and poorly
developed peripheral strands or none; sporangia pale, globose;
velum very narrow; megaspores small, gray, with a single tubercle
on each apical face, placed centrally within the triangle; on the
lower face, several smaller, placed variably.

Distribution: Africa, Nigeria, along the Niger River, Nupe.

Description from Kuhn, Motelay and Vendryés, and Sadebeck
in Engl. & Prantl.

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 115

10. I. adspersa A. Br. in Bory & Dur. Expl. Sci. Alg. pl. 37.
fig. 8. 1846-49; Milde, Fil. Eur. 286. 1867; Baker, Fern Allies,
129. 1881, and Jour. Bot. 18:106. 1880; Motel. & Vendr.
Actes Soe. Linn. Bord. 36: 381. pl. 11. fig. 5-6. 1883.

I. setacea Perreymondu Bory, Compt. Rend. Acad. Paris
18: 1165. 1844, and Flora 27: 716. 1844.

I. lineolata Dur. in Motel. & Vendr. Actes Soc. Linn. Bord.
36° S81; 1883.

Calamaria adspersa Kuntze, Rev. Gen. Pl. 2: 828. 1891-93.

Corm 3-lobed; leaves 9-25, 7-16 cm. long, very slender, fili-
form, attenuated, with wide membranaceous margin at base ex-
tending 1-2 cm. above level of sporangium; bases sometimes per-
sistent as brown scales; stomata common; peripheral strands 4
or more; ligule longer than wide, ovate-acuminate; sporangia
oval, 3-5 mm. long, spotted with brown sclerenchyma cells;
velum very narrow; megaspores white, sharply angled, 328-400 p
in diameter, with few coarse warts and very prominent com-
missural ridges; microspores light brown, 27-34 u long, spinulose,
sometimes wing-crested.

Distribution: Algeria.
Specimens examined:

Algeria: Oran, May, 1844, Durieu (Mo. Bot. Gard. Herb.) ; dry
flats in field, Oran, 28 April, 1842, ex Herb. Motelay (Mo.
Bot. Gard. Herb.); near Oran, 12 June, 1844, Bory (Gray
Herb.) ; along old route from Figuiers to Oran, 24 April, Oc-
tober, 1852, Herb. des Flores Européenes (Balansa) 25 (Mo.
Bot. Gard. Herb. and Gray Herb.) ; Plateau du Djebel Santo,
near Oran, May, 1857, Flores Regionales Algeria (Weddell)
16 (U. 8. Nat. Herb.); Flora Africae borealis, 1910-1911,
Dj. Habibi, Gandoger (Mo. Bot. Gard. Herb.) ; Oran, 1907,
Gandoger (Mo. Bot. Gard. Herb.); in exsiccated pools,
mountain Djebel Santo, near Oran, 14 March, 1876, Warion
188 (Gray Herb.).

The above species can be readily distinguished from J. velata
A. Br. by its narrow velum (in contrast to one almost complete),
by its narrower leaves, and most markedly by the smaller mega-
spores, of which the markings resemble more nearly those of
I. Boryana Dur.

[Vol. 9
116 ANNALS OF THE MISSOURI BOTANICAL GARDEN

11. I. Boryana Dur. Bull. Soc. Bot. Fr. 8: 164. 1861; Milde,
Fil. Eur. 284. 1867; Baker, Fern Allies, 130. 1887, and Jour.
Bot. 18: 107. 1886; Motel. & Vendr. Actes Soc. Linn. Bord.
36: 353. pl. 10. fig. 1-10. 1888.

Calamaria Boryana Kuntze, Rev. Gen. Pl. 2: 828. 1891-93.

Corm 8-lobed; leaves (10) 15-80, 12-20 em. long, loosely ar-
ranged at base, rather coarse, tapering gradually to apex, with
wide membranaceous margin suddenly narrowed a few millime-
ters above sporangium level; stomata numerous; peripheral
strands 6, frequently with accessory strands; ligule deltoid; spo-
rangia subglobose to oblong, 3-8 mm. long, sometimes with brown
spots; velum complete or nearly so; megaspores white when
dry, dark when wet, 400-640 in diameter, marked with few
large and scattered smaller warts, sometimes confluent on the
basal face to produce very short, irregularly lobed, rounded ele-
vations; microspores reddish-brown, 26-33 y long, spinulose.

Distribution: France, Landes.
Specimens examined:

France: “Etang de Cazau,” Landes, 7 September, 1863, Durieu
(Mo. Bot. Gard. Herb. and U. 8. Nat. Herb.), Typs;
“Etang de St. Julien,” Borne, Landes, 31 July, 1863, Durie
(Mo. Bot. Gard. Herb.) ; “Etang de Cazau,” near Bordeaux,
September, 1860, Durieu (Mo. Bot. Gard. Herb., Gray Herb..,
and N. Y. Bot. Gard. Herb.); Etang de Cazau, near San-
guinet, 3 September, 1860, and 14 July, 1861, Schultz
(Durieu) 778 (N. Y. Bot. Gard. Herb:, Mo. Bot. Gard.
Herb., and U. 8. Nat. Herb.); in field, Etang de Cazau, 4
September, 1861, Gay (Gray Herb.); Sanguinet, 5 July,
1863, Durieu (Mo. Bot. Gard. Herb.) ; Sanguinet, 19 July,
1863, Durieu (Gray Herb.) ; Etang de Sanguinet, near Cazau,
July, 1868, Durieu (N. Y. Bot. Gard. Herb.); Sanguinet
(Landes), 23 July, 1900, Neyraut (Mo. Bot. Gard. Herb. and
Univ. Minn. Herb.); Etang d’Aurelion (Landes), June,
1861, Foucault, (Mo. Bot. Gard. Herb.) ; Etang de Cazau, 17
August, 1890, Neyraut (Mo. Bot. Gard. Herb.) ; near Seig-
nosse (Landes), 2 August, 1891, Neyraut (Mo. Bot. Gard.
Herb.) ; Parentis (Landes), 9 July, 1893, Neyraut (Mo. Bot.
Gard. Herb.); Sanguinet, 27 September, 1860, Motelay
1903 (U. S. Nat. Herb.); “mixed with Durieu’s lacustris,

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 17

Lac de Guery, 23-27 August, 1861, Motelay misit,’ Herb.
Eaton (Mo. Bot. Gard. Herb.).

12. I. tenuissima Boreau, Bull. Soc. Ind. d’Angers, 269.
1850; Grenier & Godron, Fl. Fr. 3: 650. 1855-56; Milde, Fil.
Eur. 285. 1867; Motel. & Vendr. Actes Soc. Linn. Bord. 36: 351.
1883; Baker, Fern Allies, 131, 1887, and Jour. Bot. 18: 107.
1880; Bot. Centralbl. 57: 246. 1894.

I. Viollaei F. Hy, Jour. de Bot. 8: 96. 1894.

Calamaria tenuissima Kuntze, Rev. Gen. Pl. 2: 828. 1891-93.

Corm 3-lobed; leaves 7-12, 7-12.5 cm. long, 3-angled, erect,
slender, gradually tapering from base to apex; stomata fairly
common; peripheral strands not evident; ligule small, triangular ;
sporangia globose, 2-3 mm. long, with velum complete or nearly
sO; megaspores creamy in color when dry, brown when wet,
400-480 u in diameter, with few large warts (4 or 5) on upper
faces, more on basal (about 13-15); commissural ridges promi-
nent; microspores 25-33 » long, with numerous long, blunt spines.

Distribution: Province of Riz-Chauvron, Haute-Vienne,
France.

Specimens examined:

Central France: Haute-Vienne, without date, Boreau (Gray
Herb.) ; Riz-Chauvron, 25 September, 1856, Schultz (Cha-
boisseau) 395 (Mo. Bot. Gard. Herb.); Riz-Chauvron,
Haute-Vienne, 5 September, 1865, Schultz (Deloynes) 395b.
(U. S. Nat. Herb.) ; Riz-Chauvron, September, 1857, Cha-
boisseau (Mo. Bot. Gard. Herb. and Gray Herb.); Riz-
Chauvron, Haute-Vienne, 7 September, 1859, Chaboisseau
(N. Y. Bot. Gard. Herb.) ; Riz-Chauvron, 20-25 September,
1860, Chaboisseau 70 (Mo. Bot. Gard. Herb. and Gray
Herb.); Riz-Chauvron, 1864, Motelay (Mo. Bot. Gard.
Herb.); RizsChauvron, 8 September, 1865, Chaboisseau
(Mo. Bot. Gard. Herb.) ; Etang du Riz-Chauvron, Septem-
ber, 1869, Durieu (Gray Herb.); near St. Léomer, Vienne,
7 August, 1893, Violleau 427 (Mo. Bot. Gard. Herb.) ;
Etang de La Harpe near Loreux (Loir et Cher), 28 July,
1883, Martin 19 (N. Y. Bot. Gard. Herb.); “La Harpe,”
Loreux (Loir et Cher), 7 August, 1876, Le Grand (N. Y.
Bot. Gard. Herb.) ; St. Léomer, Vienne, August, 1893, F. Hy

oie (ms Gees

{Vol. 9
118 ANNALS OF THE MISSOURI BOTANICAL GARDEN

(Mo. Bot. Gard. Herb.); Riz-Chauvron, August, 1893, F.
Hy (Mo, Bot. Gard. Herb.).

Germany: with lacustris, Wjellingsee, Biitow, Pomerania, Doms
(Mo. Bot. Gard. Herb.).

The specimen from Pomerania is a single one, which shows un-
doubted tenuissima characters, both in vegetative and reproduc-
tive features. It is a question whether it was not placed with the
Pomerania material originally through an error. No other sta-
tions than those in central France have been brought to light to
date, save this distant one, as indicated by a single plant.

Hy’s species J. Viollaei was based on J. tenwissima Bor. speci-
mens which showed brown lines about the sporangium at the
base of the leaf. At best, this character would serve only in
separating a form, Several American species show in the same
stand both pallid and spotted-leaved forms, as J. melanopoda
Gay & Dur. The species is very closely related to J. Boryana
Dur,, rather than to J. adspersa, as Grenier and Godron indicate.

13. L. dubia Genn. Comment. Critt. Ital. (2): 104. 1861;
A. Br, Monatsber. K. Akad. Wiss. Berlin, 606. 1863; Milde, Fil.
Eur. 282. 1867.

Calamaria dubia Kuntze, Rev. Gen. Pl. 2: 828. 1891-93.

Corm 3-lobed; leaves 18-22 em. long, yellow-green, soft, fine,
narrowly wing-margined at the base; ligule very broadly ovate;
weak peripheral strands with no accessories; sporangia com-
pletely covered by velum, devoid of colored cells; megaspores
480-560 , similar to J. velata, but with commissures somewhat
smaller and sharper, causing sharper angles in joming the equa-
tor; warts smaller and less distinct; microspores of two sorts,
some similar to J. velata, others with exospore extended into
wing, cristate and lobed on back.

Distribution: Island of Magdalena, Sardinia.

Description from Braun and Milde.

14. I. olympica A. Br. in Milde, Fil. Eur. 285. 1867; Motel.
& Vendr. Actes Soc. Linn. Bord. 36: 362. 1888.
Jalamaria olympica Kuntze, Rev. Gen, Pl. 2: 828. 1891-93.

Corm 3-lobed; leaves 3-5 em. long, light green, 44 mm. broad
above sheath; stomata numerous; peripheral strands less devel-

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 119

oped than in J. Boryana and I. tegulensis; sporangia small, 2
mm. long, without thickened cells; velum covering 1/3-2/3 of
sporangium; megaspores white, 360-440 u, covered with unequal
hemispherical warts on the basal face, with smaller more numer-
ous tubercles, often inconspicuous, on the apical faces; micro-
spores 30 u long, 20 wide, spinulose.

Distribution: small pools in granite plains of Olympus near
Brussa of Bithynia.

Description based on Milde’s data.

15. I. velata A. Br. in Bory & Dur. Expl. Sci. Alg. pl. 37.
fig. 1. 1846-49; Genn. Comment. Critt. Ital. 103. 1861; A.
Br. Monatsber. K. Akad. Wiss. Berlin, 602. 1863; Milde, Fil.
Eur. 280. 1867; Franchet, Fl. Loir et Cher, 747. 1885, and Bull.
Soc. Bot. Fr. 31: 349. 1884; Motel. & Vendr. Actes Soc. Linn.
Bord. 36: 384. pl. 15. fig. 8-9. 1883.

I. decipiens Bory, Flora 29: 719. 1846.

I. setacea var. Delilei Bory, Compt. Rend. Acad. Paris 18:
1165. 1844, and Flora 27: 716. 1844.

I. Chaboissaei Nym. Consp. Fl. Eur. 871, name only.

Calamaria longissima Kuntze, Rev. Gen. Pl. 2: 828. 1891-93.

Corm 3-lobed; leaves 5-30, sometimes 40, 8-24 cm. long, ta-
pering to apex, rather fine, with wide membranaceous border at
base extending 14 cm. above sporangium level; base of leaf some-
times persisting as a brown papery scale; stomata numerous;
peripheral strands usually 6, rarely only 4, frequently with
weaker accessory strands in variable number; ligule triangular
lanceolate; sporangium 3-5 mm. long, nearly (4/5) to com-
pletely covered by velum; megaspores 420 (360) —580 u in diam-
eter with few large warts on upper faces (3-10), and with
mixed large and small warts on basal face; microspores red-
brown, 26-33 p long, densely spinulose.

Distribution: Sicily, Corsica, Algeria.

Specimens examined:

Sicily: near Misilmer, 24 May, 1856, Pl. Siculae 242 (Huet de
Pavillon) (Mo. Bot. Gard. Herb.).

Corsica: near Bonifacio, on granite, rare, April, 1893, Rever-
chon (Mo. Bot. Gard. Herb.) ; Corsica, Rabenhorst Crypt.
Vasc. Eur. (Reveliere) 105 (N. Y. Bot. Gard. Herb.).

[Vol. 9
120 ANNALS OF THE MISSOURI BOTANICAL GARDEN

Algeria: wet places near Bona, about 1860, LeTourneur (Mo.
Bot. Gard. Herb.) ; ponds of Chaiba near Coléah, 18 April,
1859, Herb. Font. norm. (Clauson) 99 (Gray Herb.) ; Daia,
29 April, 1859, Herb. Font. norm. (Clauson) 99 bis (Gray
Herb.); Lac de Ouled Dieb., between Bone and LaCalle,
LeTourneux (Gray Herb.); swamps, Boudom, 12 April,
1861, Frag. Fl. Alg. Exsic. 499 (Bourlier) (U.S. Nat. Herb.) ;
mares de Bou Zegart between Oued Khamis and Djebel
Azieb Dahra, Prov. Oran, 20 May, 1875, Warion Pl. Atl.
Sel. (Cosson) 189 (Gray Herb. and U. S. Nat. Herb.) ;
Maison Cairee, April, 1878, Debeauz (N. Y. Bot. Gard.
Herb.) ; without definite locality, 1906, Gandoger (Mo. Bot.
Gard. Herb.).

15a. Forma longissima Pfeiffer, comb. nov.

I. longissima Bory & Dur. Compt. Rend. Acad. Paris 18: 1165.
1844.

I. velata var. longissima A. Br. in Bory & Dur. Expl. Sci. Alg.
pl. 37. fig. 2. 1846-49.

Differs from the species in the greater leaf length, as much as
50-65 cm. in the larger plants. There is a tendency toward a
smaller number of leaves (8-12).

Distribution: Algeria.

Specimens examined:

Algeria: LaCalle, May, 1844, Durieu (Mo. Bot. Gard. Herb.) ;
LaCalle, May, 1844, Bory (Gray Herb.) ; inundated prairies,
24 June, 1844, Motelay (Mo. Bot. Gard. Herb.) ; LaCalle,
1864, Durieu (Gray Herb.); LaCalle, June, 1884, Debeaux
(U. S. Nat. Herb.).

From the presence of persistent papery brown bases of leaves
in some specimens it seems likely that this form may assume
practically a terrestrial habit, as in J. Nuttall A. Br. and J. But-
lert Engelm.

The species shows great variability, and its close allies, differ-
ing from it in sometimes inconspicuous features, are correspond-
ingly difficult to delimit. Braun and Engelmann were eventually
inclined to consider J. Boryana, I. tenuissima, I. Perralderiana, I
baetica, I. tegulensis, I. dubia and I. longissima as forms or sub-
species of J. velata. There is doubtless a complex here, which
properly should be solved by those able to work with an abun-

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE P21

dance of living material of the forms concerned. A relatively
small representation of dried material is inadequate for the prob-
lem. J. longissima is reduced here to a form since there seems
no basis for separation but leaf length. J. Perralderiana is re-
duced to a variety, differing from the species in having more
slender leaves and smaller megaspores. The other species are re-
tained in their present rank with the knowledge that they might
readily be reduced to varieties, if geographical limitations were
not distinct.

15b. Var. Perralderiana Pfeiffer, comb. nov.

I. Perralderiana Dur. & LeTourn. in Kralik, Pl. Alg. Exsic.
157; Milde, Fil. Eur. 282. 1867; Kuhn, Fil. Afr. 196. 1868;
Baker, Jour. Bot. 18: 107. 1880, and Fern Allies, 130. 1887;
Motel. & Vendr. Actes Soc. Linn. Bord. 36: 354. pl. 11. fig. 7, 8,
9. 18838.

Calamaria Perralderiana Kuntze, Rev. Gen. Pl. 2: 828. 1891-
93.

Like the species in habit except for very fine leaves; mega-
spores 380-475 up in diameter, marked with a few large warts
and many smaller ones; microspores 26-83 p long, finely, densely
spinulose, sometimes crested.

Distribution: Algeria.

Specimens examined:

Algeria: pool of the fountain of Ain Sumta, by the gorges Ak-
fadou, eastern Kabylie, 1 August, 1861, Cosson (Gray
Herb.), Type; “cultivated by Durieu at Jardin de Bot-
anique de Bordeaux, coming from Jurajura’, 11 July, 1871,
LeTourneux (Mo. Bot. Gard. Herb.).

16. I. tegulensis Genn. Comment. Critt. Ital. (2): 106. 1861;
Milde, Fil. Eur. 288. 1867; A. Br. Monatsber. K. Akad. Wiss.
Berlin, 608. 1864; Fl. Ital. 1867; Baker, Jour. Bot. 18: 107.
1880; Motel. & Vendr. Actes Soe. Linn. Bord. 36: 363. pl. 11.
fig. 3-4. 1883.

I. Tiguliana Genn. Comment. Critt. Ital. (1): 42. 1861.

Calamaria tegulensis Kuntze, Rev. Gen. Pl. 2: 828. 1891-93.

Corm 38-lobed; leaves 5-20, 20-80 cm. long, yellow-green, very
fine, erect, with narrow membranaceous margins little elongated

[Vol 9
122 ANNALS OF THE MISSOURI BOTANICAL GARDEN

above sporangium level; stomata common; peripheral strands 6;

ligule small triangular; sporangia oval, 4-6 mm. long, almost or

completely covered by velum; megaspores white, 400-520 yu

(rarely 600) in diameter, with large well-rounded tubercles on

all faces, sometimes with scattered small additional warts on

upper faces; commissural and equatorial ridges frequently nodu-
lose; microspores fawn-colored, 26-33 p long, conspicuously spin-
ulose, sometimes slightly crested.

Distribution: Sardinia.

Specimens examined:

Sardinia: submersed in aqueducts, near Pula, 22 May, 1863,
Ascherson & Reinhardt (Mo. Bot. Gard. Herb.) ; Pula, June,
1863, Ascherson & Reinhardt (Mo. Bot. Gard. Herb. and
Gray Herb.) ; Pula, June, 1863, Ascherson (N. Y. Bot. Gard.
Herb.).

This species is one of the forms very closely related to I. velata
A. Br. It may be distinguished partly by greater length of
leaves, which are finer, and partly by the tendency toward
smaller megaspores.

17. I. alpina Kirk, Trans. N. Z. Inst. 7: 377. pl. 25. 1875;
Baker, Fern Allies, 127. 1887, and Jour. Bot. 18: 70. 1880;
Motel. & Vendr. Actes Soe. Linn. Bord. 36: 368. 1883.

Calamaria alpina Kuntze, Rev. Gen. Pl. 2: 828. 1891-93.
Corm 3-lobed; leaves 10-50, 10-40 em. long, dark green, stout,
rigid, tapering to a point, with a wide membranaceous margin
narrowed immediately above sporangium; stomata present but
not numerous; peripheral strands lacking; ligule short, ovate-
triangular; sporangium oblong, 5-7, rarely 9, mm. in length; vel-
um complete; megaspores white when dry, brown-black when
wet, 400-520 u (rarely only 320) in diameter, chiefly smoothish,
sometimes lightly marked with large tubercles, few in number;
microspores rusty-brown, 24-3ly in length, with numerous
spines.
Distribution: New Zealand.
Specimens examined:
New Zealand: Lake Guyon, So. Isl., without date, Kirk (N. Y.
Bot. Gard. Herb.) ; Lake Guyon, Nelson, alt. 3000 ft., Kirk
239 (U.S. Nat. Herb. and Gray Herb.) ; Lake Guyon, Nel-

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 123

son, Kirk 136 (U.S. Nat. Herb.); Lake Guyon, Kirk (Mo.
Bot. Gard. Herb.); Lake Rotoiti, alt. 1800 ft., January,
1881, Cheeseman 56 (N. Y. Bot. Gard. Herb.) ; Lake Rotoiti,
alt. 1800 ft., 1 January, 1881, Cheeseman (U.S. Nat. Herb.
and Mo. Bot. Gard. Herb.); Lake Guyon, 3000 ft., Hector
(Gray Herb.) ; Lake Rotoiti, Nelson, January, 1898, Cheese-
man (Gray Herb.).

Kirk’s material from Lake Guyon shows rather shorter, stouter
habit in the leaves, which do not exceed 17 cm. in any case.
Cheeseman’s material derived from Lake Rotoiti invariably
shows longer leaves, from 25-40 cm., coarse, but appearing more
flexuous. Since most of the material is unfortunately lacking in
dates, it is impossible to tell whether the difference in size is to
be related to seasonal change, ecological factors, or morphological
variation. All material is therefore included under the species.

18. I. Kirk A. Br. Monatsber. K. Akad. Wiss. Berlin, 2. 1869;
Kirk, Trans. N. Z. Inst. 2:107 pl. 7. 1875.; Baker, Fern Allies,
127. 1887, and Jour. Bot. 18: 69. 1880; Motel. & Vendr. Actes
Soc. Linn. Bord. 36: 390. 1883.

Calamaria Kirkit Kuntze, Rev. Gen. Pl. 2: 828. 1891-93.

Corm 3-lobed; leaves 5-15, 7-13 cm. long, medium slender,
rather abruptly attenuate at the tip to a very long fine setaceous
apex; stomata rare, even at tip; peripheral strands lacking;
ligule short, triangular-ovate; sporangia globose, 2-8 mm. in
length, completely covered by velum; megaspores white, 460-
580 u in diameter, marked on all surfaces with numerous closely
set small tubercles, with very slight tendency to confluence on
the basal face; microspores small, 17-25 yp, smooth.

Distribution: mountain lakes in New Zealand.

Specimens examined:

New Zealand: Whangape Lake, Kirk (Mo. Bot. Gard. Herb.,
Gray Herb., and U. S. Nat. Herb.), corypz; Whangape
Lake, Hector (Gray Herb.); Lake Tekapo, Canterbury,
South Isl., 7 January, 1883, Cheeseman (U.S. Nat. Herb.) ;
ponds near Lake Tekapo, Canterbury Alps, alt. 2000 ft.,
Cheeseman (Mo. Bot. Gard. Herb.) ; Lake Whangape, 1882,
ez herb. Martindale (Cheeseman coll?) (Mo. Bot. Gard.
Herb.) ; Lake Whangape, Waikato, N. Isl., Cheeseman (Mo.

[Vol. 9
124 ANNALS OF THE MISSOURI BOTANICAL GARDEN

Bot. Gard, Herb.) ; Whangape Lake, January, 1879, Cheese-
man (Gray Herb.).

19. I. Gunnii A. Br. in Herb. Hooker. 1866; A. Br. Mo-
natsber. K. Akad. Wiss. Berlin, 5385. 1868; Baker, Fern Allies,
124, 1887, and Jour. Bot. 18: 66. 1880; Motel. & Vendr. Actes
Soc. Linn. Bord. 36: 347. 1883.

Isoetes sp. Hooker, Fl. Tasm. 2: 158. 1860.

I. lacustris (L.) Rodway, Tasm. Fl. 279. 1908.

Calamaria Gunnu Kuntze, Rev. Gen. Pl. 2: 828. 1891-93.

Corm 8-lobed; leaves 30-50, 3-18 cm. long, stout, tough, ab-
ruptly-pointed at tip, with wide membranaceous border at base,
continued upward 4-6 times the length of sporangium; stomata
and peripheral strands none; ligule short, with cordate base;
sporangium oblong, 3-6 mm. long, marked with brown cells, with
velum lacking; megaspores ashy or light brown when dry, dark
shining brown when wet, 600-800 u in diameter, marked with
small distant tubercles, rarely elongated in one diameter, or
somewhat ridge-like; microspores brown, 29-86 u long, chiefly
spinulose.

Distribution: Tasmania, mountain lakes.

Specimens examined:

Tasmania: Lake Fenton, Mt. Field, 3000 ft. alt., 1869, v.
Mueller (N. Y. Bot. Gard. Herb.) ; Mt. Field, Rodway (Mo.
Bot. Gard. Herb.); Hartz Mts., 1918, Rodway (Mo. Bot.
Gard. Herb.); Hobart, 1918, Rodway (Mo. Bot. Gard.
Herb.).

In this short coarse plant, the upper half of the leaves usually
appears a dark green, the base brown, in herbarium specimens.
The bulb formed by the sporangia is apt to be 3-4 cm. in di-
ameter. According to F. v. Mueller, the leaves are rigid enough so
that the term “water-porcupine” seemed fitting for plants grow-
ing in Lake Fenton on Mt. Field. He reported corms as large as
one’s fist, and a habit of growth in groups that resulted in a
polster.

All of the material examined at Mo. Bot. Gard. in 1918 was
obtained through the courtesy of L. Rodway of Hobart, Tasmania,
who is presumably the collector.

1922] ~
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 125

20. I. Drummendii A. Br. Monatsber. K. Akad. Wiss. Berlin,
593. 1863, and 542. 1868; Baker, Jour. Bot. 18: 70. 1880, and
Fern Allies, 128. 1887; Motel. & Vendr. Actes Soc. Linn. Bord.
36: 319. pl. 13. fig. 4-5. 1883.

Calamaria Drummondu Kuntze, Rev. Gen. Pl. 2: 828. 1891-93.

Corm 3-lobed; leaves 18 or fewer, 3-7 cm. long, somewhat
loosely arranged, coarser than J. Mueileru and I. tripus, bright
green; stomata present; no peripheral strands; ligule very short,
cordate-triangular; sporangium rounded, without sclerenchyma
cells; velum lacking; megaspores whitish when dry, dark brown
when wet, 340-470 up in diameter, marked with numerous (36-40)
minute tubercles, distinct on apical faces, sometimes confluent in
meandriniform ridges on basal face; microspores 30-39 u long,
violet-ashy, short denticulate-muricate.

Distribution: Australia: Swan River.

Specimens examined:

Australia: wet rocks, Toodyay, coll. O. W. F. (N. Y. Bot. Gard.
Herb.) ; Tea Tree Gully, South Australia, 13 October, 1917,
Osborn (Mo. Bot. Gard. Herb.); National Park, Belair,
27 September, 1917, Osborn (Mo. Bot. Gard. Herb.) ;
Echunga, South Australia, 1 September, 1921, Osborn (Mo.
Bot. Gard. Herb.).

The plants of the first collection were small, consisting of 5 or 6
fine leaves, about 3 cm. long, bearing sporangia 2-2.5 mm. in
length, without velum. The megaspores were 360-470 u in diam-
eter, chiefly 480 u, and showed rather close anastomosing rid-
ges on basal face. The microspores, densely spinulose, 32-39 yu
in length, were brown in the mass, with a violet cast.

21. I. amazonica A. Br. acc. Kuhn in Martius, Fl. Bras. 1°: 647.
pl. 79. fig. 5-6. 1884; Baker, Jour. Bot. 18: 109. 1880, and Fern
Allies, 183. 1887; Motel. & Vendr. Actes Soc. Linn. Bord. 36: 351.
1883.

Calamaria amazonica Kuntze, Rev. Gen. Pl. 2: 828. 1891-93.

Corm 3-lobed; leaves 10-12, 5-7 em. long, somewhat rigid;
stomata and accessory peripheral strands present; ligule short,
triangular; sporangium small (2—2.5 mm.), lacking velum; mega-
spores white to ashy, 430-510u in diameter, with numerous
warts, single or confluent into verrucose ridges; microspores 33-
40 u, finely tuberculate.

[Vol 9
126 ANNALS OF THE MISSOURI BOTANICAL GARDEN

Distribution: Brazil.

Specimens examined:

Brazil: near Santarem, Para, September, 1850, Spruce (Gray

Herb.), TYPE?

In the Mo. Bot. Gard. Herb., there are some immature spe-
cimens from “ditches of the Agulhas Negras, Serra do Itatiaia,
State of Santa Catharina, Brazil, Rio de Janeiro, March, 1894. E.
Ule.” These consist of 4 or 5 leaves, 2-3 cm. in length, rather
soft, light green, with fairly numerous stomata and no evident
peripheral strands. There is fragmentary material of megaspores,
almost smooth or lightly marked with wavy prominences;) the
diameter appears to be 400-468. The microspores, 23-27 u
long, are smooth or with minute tubercles. The form was placed
by Eaton in J. amazonica. Such fragmentary, doubtfully mature
material is difficult to place with certainty. The geographic
range is great if this form occurs in these two states at opposite
ends of Brazil in different river systems.

Quite different specimens of Dusen’s collecting from the same
station seem to accord better with J. Martu A. Br., though again
the spores are immature.

22. I. Gardneriana A. Br. Verh. Bot. Ver. Brandenb. 4: 330.
1862; Mett. Fil. Lechl. Fase. 11: 36; Kuhn in Martius, FI. Bras.
1°: 647. pl. 79. fig. 1-4. 1884; Motel. & Vendr. Actes Soc. Linn.
Bord. 36: 349. 1883; Baker, Jour. Bot. 18: 110. 1880.

Calamaria Gardneriana Kuntze, Rev. Gen. Pl. 2: 828. 1891-93.

Corm 3-lobed, 3-3.5 em. broad; leaves erect, coarse, firm, 30
-32 cm. long, attenuate at apex, somewhat obtuse, obscurely
quadrangular; peripheral strands 4, strong; stomata present;
ligule triangular, obtuse, hardly half as long as the sporangium;
velum incomplete; sporangium dark, about 10 mm. long; mega-
spores 540-700 u in diameter, dark brown whether wet or dry,
with number of fine tubercles, distinct on all faces; microspores
very smooth, white, 35 u in length.

Distribution: Province of Goyaz in Brazil; Paraguay.

Description from Braun and Kuhn.

23. I. elatior F. Muell. in A. Br. Linnaea 25: 722. 1852, and
Monatsber. K. Akad. Wiss. Berlin, 536. 1868; Motel. & Vendr.
Actes Soe. Linn. Bord. 36: 348. 1883.

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 127

Isoetes tasmanica F. Muell. in Dur. Bull. Soc. Bot. Fr. 11: 104.
1864.
Calamaria elatior Kuntze, Rev. Gen. Pl. 2: 828. 1891-93.

Corm 3-lobed; leaves numerous and long, flexuous; stomata
and peripheral strands lacking; ligule cordate, elongated; spo-
rangia dark, practically black with sclerenchyma cells; velum
lacking; megaspores white when dry, black when moist, 480-
650 up in diameter, marked with minute, very dense tubercles
all over surface, confluent into ridges; microspores coffee-brown,
(28) 32-35 u in length, densely muricate.

Distribution: Tasmania.

Specimen examined:

Tasmania: Archer (Gray Herb.).

This sheet is marked “J. lacustris. Tasmania. Coll. R. C.
Gunn.” to which Engelmann, Feb. 1880, made note, “Not col-
lected by Gunn. Identical with J. elatior F. Muell. Archer legit.”

The megaspores are 570-650» in diameter, with minute ele-
vations above, crinkly in effect, but not anastomosing on the
basal face. The microspores range from 28 to 34u, and are
covered with numerous fine spines. The leaves are 14-18 in
number, about 30 em. long, and lack a velum.

Description in part from Braun.

24. I. Muelleri A. Br. Monatsber. K. Akad. Wiss. Berlin, 541.
1868; Baker, Jour. Bot. 18: 69. 1880, and Fern Allies, 127.
1887; Motel. & Vendr. Actes Soc. Linn. Bord. 36: 389. 1883.

I. tenuissima F. Muell. (non Boreau) Motel. & Vendr. Actes
Soe. Linn. Bord. 36: 389. 1883.
Calamaria Muelleri O. K. Rev. Gen. Pl. 2: 828. 1891-93.

Corm 3-lobed, with loose bulb of leaves; leaves few, 7 em. long,
narrow, attenuate, pale green, diaphanous; stomata present;
peripheral strands lacking; ligule cordate-ovate; velum complete,
closed, pale; sporangium becoming dark, with all epidermal cells
thickened, some light, some very dark; megaspores 330-390 u,
white or ashy white, marked with less numerous (20-25 tubercles
per face) unequal tubercles, even confluent into branching
ridges.

Distribution: Eastern Australia, wet places at Rockhampton.

[Vol. 9
128 ANNALS OF THE MISSOURI BOTANICAL GARDEN

25. I. histrix Bory & Dur. Compt. Rend. Acad. Paris 18: 1167.
1844; A. Br. in Bory & Dur. Expl. Sci. Alg. 36. fig. 1. 1846-49;
Milde, Fil. Eur. 288. 1867; Kuhn, Fil. Afr. 195. 1868; Baker,
Jour. Bot. 18: 110. 1880, and Fern Allies, 134. 1887; Motel.
& Vendr. Actes Soc. Linn. Bord. 36: 394. 1883.

Calamaria Hystriz Kuntze, Rev. Gen. Pl. 2:828. 1891-93.

I. Delalandei Lloyd, Fl. Ouest. Fr., ed. 1, 728. 1854.

Cephaloceratodon hystrix Genn. Comment. Critt. Ital. (3):
111. 1862.

Corm 3-lobed; leaves 9-22, 5-10 cm. long, linear, firm, with
membranaceous margin disappearing at sporangium level; bases
of leaves persistent as hard brown horny structures, with central
short broad tooth and two longer lateral spine-like teeth, produc-
ing an exaggerated effect of size at the corm level through
persistence from one season through succeeding ones; stomata
numerous; peripheral strands 4, strongly developed; ligule ovate-
triangular; sporangia 4-6 mm. long, completely covered by
velum; megaspores white, 400-560 (600) u in diameter, closely
marked with small tubercles or warts, becoming somewhat con-
fluent, especially on the basal surface; microspores brown, 25-
33 uw long, spinulose.

Distribution: Algeria, islands of Mediterranean, Italy, France.

Specimens examined:

Algeria: dry sands, hills of LaCalle, March, 1841, Durieu (Mo.
Bot. Gard. Herb.), tTypn; dry hills, LaCalle, 30 March,
1841, Durieu (Gray Herb.) ; near Mascara, May, 1844, Bory
(Gray Herb.) ; Mascara, May, 1841, Durieu (Mo. Bot. Gard.
Herb.) ; near Mascara, 14 September, 1864, Warion (U. 5S.
Nat. Herb.) ; “Telegraph, infer Alger,” April, 1856, Guthnik?
(N. Y. Bot. Gard. Herb.) ; in wet sandy places at Sidi-Dako,
near Mascara, 28 April, 1875, Warion Pl. Atl. Sel. 187
(Kralik) (U. 8. Nat. Herb. and Gray Herb.); wet sands of
the plain of Chearfa, Mostaganem, Prov. Oran, 19 May,
1875, Cosson (Gray Herb.); Dj. Ouach. Prov. Constantine,
26 May, 1880, Cosson (Gray Herb.); LaCalle, April, 1884,
Debeaux (U. 8. Nat. Herb.); Bone, 1906, Gandoger (Mo.
Bot. Gard. Herb.).

Tunis: north of Ain-Draham, 4 July, 1883, Cosson et al. (Gray
Herb. ).

Corsica: Bonifacio, 21 April, 1866, Mabille (Mo. Bot. Gard.

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 129

Herb.); Porto Vecchio, April and May, Reveliére (U. S.
Nat. Herb. and N. Y. Bot. Gard. Herb.).

Phrygia: dry hills near village Kaiageul, 8. of Ouchak, 30 May,
1857, Balansa 849 (U.S. Nat. Herb.).

Crete: Crete, 12 March, 1882, Reverchon (Mo. Bot. Gard. Herb.
and U.S. Nat. Herb.); Crete, ex herb. Ball (Gray Herb.).

Sardinia: Caprera I., granitic soil, 15 May, 1905, Vaccari 503
(Gray Herb.); Bancamino, 3 June, 1881, Reverchon (N. Y.
Bot. Gard. Herb.).

Italy: Castagnolo, 3 May, 1865, Caruel (Mo. Bot. Gard. Herb.) ;
wet fields, Castagnolo, Pisa, 28 November, 1862, Ball (Gray
Herb.).

France: Isle d’Yeu, Vendée, May, 1880, Grand-Marais (N. Y.
Bot. Gard. Herb.) ; near the sea coast on Isle d’ Yeu, Vendée,
May, 1883, Grand-Marais (Mo. Bot. Gard. Herb.); “mare
de Rochaute,” near Agde, 5 October, 1846, Fabre (Gray
Herb.); Ile de Houat, Morbihan, April, 1853, Lloyd 198
(N. Y. Bot. Gard. Herb.).

25a. Forma subinermis Dur. Bull. Soc. Bot. Fr. 8: 164. 1861.

I. histriz f. desquamata A. Br. Monatsber. K. Akad. Wiss.
Berlin, 617. 1864.

I. hystrix Wolsey, New Phytol. IT. 5: 45. 1861.

Cephaloceratodon gymnocarpum Genn. Comment. Critt. Ital.
(3) 2411S.) 71862:

I. histriz var. scutellata A. Br. ace. Motel. & Vendr. Actes Soc.
Linn. Bord. 36: 400. 1883.

The form differs from the species in the persistent structure
resulting from the leaf base; the former lacks the lateral horns or
teeth. There is a wider range in megaspore size, with a slight
tendency toward greater size, and the confluence of the tubercles
is sometimes quite pronounced.

Phrygia: rocky hills above the village of Kaiageul, s. of Ouchak,
30 May, 1857, Balansa 1327 (Gray Herb.).

Sardinia: near Pula, at foot of Mt. Santo, in wet declinities,
inundated in winter, alt. 30 m., granitic soil, 28 March, 1912,
Fiori & Béguinot 1607 (Gray Herb.) ; I. Caprera, July, 1863,
Ascherson & Reinhardt (Mo. Bot. Gard. Herb.); I. of
Caprera, 11 June, 1863, Ascherson & Reinhardt (Gray
Herb.).

[Vol. 3
130 ANNALS OF THE MISSOURI BOTANICAL GARDEN

France: near Cazau (Landes), 5 July, 1861, ex herb. norm. F.
Schultz (Durieu) 781 (U.S. Nat. Herb.) ; “southern France,”
July, 1861, Durieu (Gray Herb. and N. Y. Bot. Gard. Herb.) ;
near Grasse, Alpes Maritimes, 1 April, 1891, Mouwillefarines
(U.S. Nat. Herb.) ; pools near Cazau, Landes, 29 June, 1862,
Durieu (Mo. Bot. Gard. Herb.) ; sandy pastures near Etang
and village of Cazau, Landes, 1861, Durieu (Mo. Bot. Gard.
Herb.); dry sand near Cazau, September, 1861, Durieu
(Gray Herb.) ; near the sea-coast, on the Ile d’Yeu Vendée,
May, 1883, Grand-Marais (Mo. Bot. Gard. Herb.) ; Gironde,
August, 1891, Motelay (Mo. Bot. Gard. Herb.); Cazau
(Gironde), along railroad near station of Cazau, Hameau,
20 May, 1900, Neyraut (Mo. Bot. Gard. Herb. and Univ.
Minn. Herb.); Mios, Gironde, 11 July, 1897, Neyraut
(Mo. Bot. Gard. Herb. and N. Y. Bot. Gard. Herb.).

Guernsey: L’Aucresse, 15 June, 1884, Hanbury 1656 ( N. Y. Bot.
Gard. Herb.).

The plants of Neyraut collected at Mios are unusual in large
number of leaves (up to 50), but appear to be the form with a
poor development of the scaly bases.

26. I. Nuttallii A. Br. in Engelm. Am. Nat. 8: 215. 1874;
Baker, Jour. Bot. 18: 105. 1880; Engelmann, Trans. St. Louis
Acad. Sci. 4: 388. 1882; Motel. & Vendr. Actes Soc. Linn. Bord.
36: 375. 1883;-Macoun, Cat. Canad. Pl. pt. 4: 293. 1888;
Piper, Contr. U. 8. Nat. Herb. 11: 88. 1906.

I. opaca Nuttall in Engelm. Trans. St. Louis Acad. Sci. 4:
388. 1882.

I, Suksdorfu Baker, Fern Allies, 1382. 1887.

Calamaria Nuttallu Kuntze, Rev. Gen. Pl. 2: 828. 1891-93.

Corm slightly 3-lobed; leaves 13-60, 8-17 cm. long, 3-angled,
very slender, firm, erect, light green, with membranaceous mar-
gins not extended beyond sporangium level; stomata numerous;
peripheral strands 3 (sometimes 2 dorsal lacking); ligule small,
triangular; sporangia oblong, 4-7 mm. long, completely covered
by velum; megaspores white, (820) 400-528 (600) » in diameter,
densely covered by small, usually glistening, distinct papillae on
faces between prominent commissural ridges, or rarely smooth;
microspores brown, 25-30 yp in length, papillose.

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 131

Distribution: California, Oregon, Washington, Vancouver.
Specimens examined:

California: Mt. Tamalpais, Marin Co., 13 June, 1892, Palmer
2355 (U.S. Nat. Herb.) ; Tamalpais, June, 1891, Brandegee
(N. Y. Bot. Gard. Herb.); Mt. Tamalpais, Marin Co., 13
June, 1892, Mrs. Brandegee (Mo. Bot. Gard. Herb. and Univ.
Minn. Herb.); Mt. Tamalpais, Marin Co., near the big
spring on trail to Larsens, 28 June, 1896, Miss Eastwood
(Mo. Bot. Gard. Herb.) ; Pine Ridge, Fresno Co., 25 May,
1901, Thompson (Mo. Bot. Gard. Herb.) ; Soquel Point, be-
tween Santa Cruz and Capitola, 28 May, 1902, Mrs. C. H.
Thompson (Mo. Bot. Gard. Herb.); Soquel Point, Santa
Cruz, summer, 1903, Thompson (Mo. Bot. Gard. Herb.) ; San
Diego, 6 March, 1895, Brandegee (Mo. Bot. Gard. Herb.) ;
Glacier Point Meadows, edges of pools in black mucky soil,
alt. 7100 ft. (Canadian Life Zone), 6 July, 1914, Smiley
492 (Gray Herb.) ; Tuolumne Meadows, pools back of Muir
Lodge, Yosemite, alt. 8500 ft. (Canadian Life Zone), 13
August, 1916, Smiley 747 (Gray Herb.) ; Coste Madera, June,
1887, Curran (N. Y. Bot. Gard. Herb.) ; partially submerged
in sluggish stream, Williams Ranch, Tuolumne Co., 14 June,
1895, Blasdale (N. Y. Bot. Gard. Herb.).

Oregon: low pondy places and on high banks in springy situations
in Willamette Valley, Salem, Silverton, etc., June and July,
1871, Hall 693 (Mo. Bot. Gard. Herb., Gray Herb. and U.
S. Nat. Herb.) ; low grassy places, Oregon, 1871, Hall (Gray
Herb.) ; “terrestrial, under scrub-oaks,”’ Woodburn, 1 June,
1882, Thos. J. Howell (Mo. Bot. Gard. Herb. and U. 8. Nat.
Herb.) ; on springy soil and in water near Milwaukee, July,
1880, J. Howell & Thos. J. Howell 303 (Gray Herb.); on
damp springy soil and in water, near Milwaukee, July, 1880,
J. Howell (Gray Herb.); Oregon, 1886, 7. J. Howell 613
(Gray Herb.); Gladstone, 14 July, 1894, T. J. Howell 1526
(Mo. Bot. Gard. Herb., U. 8. Nat. Herb., and Univ. Minn.
Herb.) ; in shallow pool near south fall, Silver Creek Falls,
Marion Co., 29 May, 1921, Nelson (Peck) 3737 (U.S. Nat.
Herb.).

Washington: Columbia River 183-, Nuttall (Mo. Bot. Gard.
Herb.), TyPpE?; springs and meadows, W. Klickitat Co.,
May, August, 1881, Suksdorf (Mo. Bot. Gard. Herb. and U.

[Vol 9
132 ANNALS OF THE MISSOURI BOTANICAL GARDEN

S. Nat. Herb.) ; springs and meadows, W. Klickitat Co., May
and September, 1886, Suksdorf (N. Y. Bot. Gard. Herb.) ;
meadows and springy places, Columbia River, 12 March and
September, 1886, Suksdorf 917 (Mo. Bot. Gard. Herb. and
U. 8. Nat. Herb.) ; on damp ground, Falcon Valley, 16 June,
1830, Suksdorf 2373 (Mo. Bot. Gard. Herb.) ; springy places
near Bingen, W. Klickitat Co., 5 June, 1894, Suksdorf 917
(Mo. Bot. Gard. Herb.); wet ground on mountain slopes
near the Columbia River, W. Klickitat Co., 3 August, 1894,
Suksdorf 2364 (Mo. Bot. Gard. Herb.) ; on meadows, Faleon
Valley, Klickitat Co., 17 July, 1896, Suksdorf 2614 (Mo.
Bot. Gard. Herb.); on low damp ground, Falcon Valley,
W. Klickitat Co., 24 June, 1897, Suksdorf 2615 (Mo. Bot.
Gard. Herb.); on wet ground near Bingen, 14 April, 1904,
Suksdorf 4443 (Mo. Bot. Gard. Herb.).

Vancouver Island: Nanaimo, 13 July, 1887, John Macoun 14219a,
14219c (Gray Herb.); vicinity of Nanaimo, 3 July, 1908,
John Macoun 86378 (Gray Herb. and N. Y. Bot. Gard.
Herb.); Nanaimo, John Macoun (Mo. Bot. Gard. Herb.) ;
vicinity of Victoria, 10 June, 1823, John Macoun 533 (Gray
Herb.).

The peripheral strands are usually ae in number at the
angles of the 3-sided, stem; of these three, the dorsal are the
weakest, and in some cases, fail to appear. There is variation
as to persistence of bases of leaves. Many specimens show dark
brown horny bases (as long as the sporangium) surmounted by
three mniute teeth, of which the central is slightly longer than
th: lateral ones. There is variation in the megaspore character in
that, though most are rather evidently marked, some are almost
smooth.

27. I. Orcuttti Eaton, Fern Bull. 8: 13. 1900.

I. Nuttall var. Orcuttu Clute, Fern Allies, 253. 1905.

Corm slightly 3-lobed; leaves 6-14 (or even 20), 2-6.5, rarely
10, em. long, fine, erect, triangular, with narrow membranaceous
margin only at base; stomata present; peripheral strands none
or 2, weakly developed; ligule triangular; sporangia orbicular to
slightly elongated, 2-5 mm. long, completely covered by velum;
megaspores gray at maturity, brownish when wet, 216-360 un,
rarely 480, in diameter, closely marked with numerous small

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 133

indistinct papillae or almost smooth, glistening; microspores
21-27 p, rarely 29u, in length, chiefly spmulose, sometimes
smooth.

Distribution: California, Lower California.

Specimens examined:

California: mesas in low depressions, San Diego, 7 June, 1884,
Orcutt 1242 (Mo. Bot. Gard. Herb., Gray Herb., and U. S.
Nat. Herb.), TyPE; 3 mi. northeast of Clovis, Fresno Co., 16
February, 1902, Mr. & Mrs. C. H. Thompson (Mo. Bot.
Gard. Herb.); meadow, Soquel Point, Santa Cruz, 10 and
29 April, 1900, C. H. Thompson (Mo. Bot. Gard. Herb.) ;
Soquel Point near Capitola, Santa Cruz Co., 6 March, 1901,
Mrs. C. H. Thompson (Mo. Bot. Gard. Herb.); El Cajon,
April, 1895, Brandegee (Mo. Bot. Gard. Herb.) ; 5 mi. west
of Stanford University, near Los Francos Creek, 13 April,
1903, Thompson (Mo. Bot. Gard. Herb.); near Upland,
growing in desiccating pools on clay mesa, 8 March, 1917,
Ivan Johnson (U.S. Nat. Herb.) ; mesas, San Diego Co., 14
May, 1903, Orcutt (U. S. Nat. Herb.); in “Hog Wallows,
dry as early as 10 March, usually wet until May 1,” 1889,
Curran (N. Y. Bot. Gard. Herb.); Antioch, Contra Costa
Co., 7 April, 1895, Burtt Davy (N. Y. Bot. Gard. Herb.).

Lower California: near Santo Tomas, 12 April, 1886, Orcutt (Mo.
Bot. Gard. Herb.).

This form differs from J. Nuttallii A. Br. chiefly in the smaller
plants, both in length and number of leaves, and in the smaller
size of the spores. The largest megaspores of J. Orcuttii are in
the range of the smallest of J. Nuttalla. There is also a difference
in the peripheral strands in that J. Nuttall usually has three,
of which the weakest or dorsal sometimes fails to develop. In
I. Orcutti, no such strands appear in the various leaves I have
examined, though A. A. Eaton reported the presence of two
weak groups of cells, a dorsal and ventral. Brandegee’s ma-
terial from San Diego combines megaspores with prominent
markings that plainly fall in the range of J. Nuttalli (364448 ),
sporangia larger than those of J. Orcuttii, but leaves the length
of the latter (2.5-8 cm.), with no peripheral strands. Since it is
believed that the leaf characters are more subject to ecological
factors, these are here given less weight, and this specimen is

[Vol. 9
134 ANNALS OF THE MISSOURI BOTANICAL GARDEN

placed at present with J. Nuttallu, rather than with J. Orcuttu,
with which Eaton placed it.

These two species are very close to each other, and with fur-
ther evidence J. Orcuttii may prove a variety of J. Nuttallu.

28. I. humilior A. Br. Linnaea 25: 722. 1852.

I, Hookeri A. Br. Monatsber. K. Akad. Wiss. Berlin, 538. 1868;
Motel. & Vendr. Actes Soc. Linn. Bord. 36: 340. 1888.

Calamaria humitior Kuntze, Rev. Gen. Pl. 2: 828. 1891-98.

I, Stuartit A. Br. Monatsber. K. Akad. Wiss. Berlin, 589. 1868;
Motel. & Vendr. Actes Soc. Linn. Bord. 36: 339. . 1883.

Corm compressed, 2-lobed; leaves somewhat coarse, rigid,
tough, attenuate toward apex, obtuse, with somewhat thick, dark
epidermis; stomata lacking; ligule short, cordate triangular;
velum complete; sporangium small; megaspores 650-770 in
diameter, with many small, little elevated, sometimes confluent
tubercles on all faces; microspores 80-32 » long, very short den-
ticulate-muricate.

Distribution: So. River Esk, Tasmania.

The characters on which Braun separated the species J. Hookeri
from I. Stuarti (the two were originally included in the species
I. humilior by him) hardly seem of more than ecological signifi-
cance (as softness of leaves) or are within the range of variation
in any species (as dark coloring at the base of the leaves). Fur-
ther he used only one specimen on which to base J. Stuartw. It
would seem to the writer who has only the description on which
to base judgment that the relation between these two is closer
than as adjacent species, and they are accordingly united in the
original J. humilior A. Br.

29. I. melanospora Engelm. Trans. St. Louis Acad. Sci. 3:
395. 1877, and 4: 383. 1882; Baker, Jour. Bot. 18: 69. 1880;
Motel. & Vendr. Actes Soc. Linn. Bord. 36: 359. 1883; Chap-
man, Fl. Southern U. S., ed. 2, 672. 1889; Small, Fl. Southeast-
ern U. 8. 25. 1903.

Calamaria melanospora Kuntze, Rev. Gen. Pl. 2: 828. 1891-93.

Corm 2-lobed; leaves 5-11, 2.5-7 em. long, slender, tapering
very gradually to apex, almost setaceous, light green, spreading;
stomata present; peripheral strands none; ligule small, triangu-
lar; sporangium orbicular, 1-2 mm. long, completely covered by

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 135

velum; megaspores dark gray when dry, black when wet, 400-480
u in diameter, with small rough warts sometimes extended into
short narrow ridges, which rarely anastomose; commissural ridges
thin and blade-like; microspores brown, 26-31 » long, smoothish
to papillose.

Distribution: Stone Mountain, Georgia.

Specimens examined:

Georgia: shallow ponds on the summit of Stone Mt., May, 1869,
Canby (Mo. Bot. Gard. Herb., Gray Herb., and U. 8. Nat.
Herb.), typz; St. Louis culture from Stone Mt. material,
13 August, 1875, Engelmann, (Mo. Bot. Gard. Herb.) ; top
of Stone Mt., April, 1875, Gray (Gray Herb.); cultivated
by Engelmann from young plantlets brought by A. Gray
from Stone Mt., 28 September, 1875, Engelmann (Mo. Bot.
Gard. Herb.); St. Louis culture (from roots brought from
Stone Mt. in September, 1876), August, 1877, Engelmann
1954 (Mo. Bot. Gard. Herb.) ; shallow depressions on sum-
mit of Stone Mt., 13 April, 1897, ex Biltmore Herb. 4264
(Mo. Bot. Gard. Herb., Gray Herb., and U. 8S. Nat. Herb.) ;
shallow depressions on summit of Little Stone Mt., 15 May,
1897, Biltmore Herb. 4264 b (Univ. Minn. Herb.) ; Stone
Mt., 17 April, 1891, Underwood (U. S. Nat. Herb.) ; “ma-
tured in laboratory” (from Stone Mt., 17 April, 1891), Au-
gust, 1891, Underwood (U.S. Nat. Herb.); “grown in lab-
oratory until December, 1891,” (from Stone Mt., 17 April,
1891), Underwood (U.S. Nat. Herb.) ; top of Stone Mt., De
Kalb Co., 25 July, 1897, Eggert (Mo. Bot. Gard. Herb.) ;
“srown from Eggert’s plants,’ 1898, ex Herb. Eaton (Mo.
Bot. Gard. Herb. and Univ. Minn. Herb.).

30. I. lithophila Pfeiffer, sp. nov.*

Corm 2-lobed, small; leaves 6-14 in number, 10-12 cm. long,
slender but not filiform, flexuous; stomata numerous; peripheral
strands variable, none or 3, weak; ligule very small, cordate trian-
gular; sporangium 2.5-4 mm. long, orbicular to oblong, com-

J. lithophila sp. nov. Cormus bilobatus, parvulus. Folia numero 6-14, longitu-
dine 10-12 em., gracilia, flexilia, stomatibus numerosis instructa, fibris periphericis
destituta vel tribus invalidis instructa. Lingula parvula, cordato-triangulata. Spo-
rangia longitudine 2.5-4 mm, orbiculata vel oblongata, velo completo. Macro-
sporae diam. 290-360 1, madidae fuscescentes, siecae cineraceae, leves vel humili-
bus brevibus aliquantulum extentis jugis leviter ornatae. Microsporae coffeaceo-
fuscae, longitudine 30-33 y, distincte tuberculatae vel spinulosae.

[Vol. 9
136 ANNALS OF THE MISSOURI BOTANICAL GARDEN

pletely covered by velum; megaspores 290-360 in diameter,
with prominent high, rather narrow, commissural ridges; sur-
face of megaspores gray when dry, brown when wet, smooth or
faintly marked with low, short or somewhat extended, usually
distant ridges; microspores dark brown, chiefly 80-83 uy, high-
tuberculate or spiny.
Distribution: Texas.
Specimen examined:
Texas: in shallow depression in granite on east slope of Granite
Mt., 70 mi. northwest of Austin, 9 May, 1914, McAllister
(Mo. Bot. Gard. Herb. and N. Y. Bot. Gard. Herb.), TYPE.

31. I. flaccida Shuttlew. A. Br. Flora 29: 178. 1846; Am.
Jour. 3: 2. 1847; Chapman, Fl. Southern U. 8S. 602. 1889; En-
gelm. Trans. St. Louis Acad. Sci. 4: 386. 1882.

I. flaccida var. rigida Engelm. Trans. St. Louis Acad. Sci.
4: 386. 1882.

I. flaccida var. Chapmani Engelm. Trans. St. Louis Acad. Sci.
4: 386. 1882.

I. Chapmani Small, Ferns of Florida, 183. 1918.

Calamaria flaccida Kuntze, Rev. Gen. Pl. 2: 828. 1891-93.

Corm 2-lobed; leaves 8-40, 10-40 cm. long, slender, light green,
sharp-pointed, with usually narrow, membranaceous margin; sto-
matg numerous; peripheral strands 4; ligule short-triangular;
sporangia oblong, 8-5 mm. long, completely covered by the
velum; megaspores light, 300-500 u in diameter, sometimes less;
apical face rarely smooth, usually marked centrally with few
large tubercles; basal face with bold, short, rounded ridges, some-
times anastomosing; microspores light brown, 26-33 up long,
slightly papillose.

Distribution: Georgia, Florida.

Specimens examined:

Georgia: in very shallow water or entirely emersed, in wet pine-
barrens, Sumter Co., 5 July, 1901, Harper 1010 (Mo. Bot.
Gard. Herb., U. S. Nat. Herb., and Gray Herb.); in slug-
gish pine-barren stream east of Douglas, Coffee Co., 19 July,
1902, Harper 1429 (Mo. Bot. Gard. Herb., U. S. Nat. Herb.,
and Gray Herb.).

Florida: Lake Immonia, north of Tallahassee, 1842-49, Rugel
(Mo. Bot. Gard. Herb.), rypz; marshes, Apalachicola, Chap-

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE IST

man? (Mo. Bot. Gard. Herb.); lakelet of clear limestone
water near Marianna, August, 1850, Chapman (Mo. Bot.
Gard. Herb.) ; marshes, Apalachicola, 1890, Herb. Chapman
(U. S. Nat. Herb.); Manatee, April, 1878, Garber without
number (Mo. Bot. Gard. Herb. and U. 8. Nat. Herb.) ; same
place and date, Garber 2312 (Mo. Bot. Gard. Herb. and U.S.
Nat. Herb.) ; same, Garber 32 (U.S. Nat. Herb., N. Y. Bot.
Gard. Herb., and Gray Herb.) ; open miry places in Turnbull
Swamp, Halifax River, May, Curtiss 3813 (U. S. Nat.
Herb.) ; Lake Flirt, August, 1878, Garber (Mo. Bot. Gard.
Herb.).

31a. Var. alata (Small) Pfeiffer, var. nov.

I. alata Small, Ferns of Florida, 133. 1918.

Similar to the species in stature and leaf characters, but dif-
fering in spore markings; upper faces usually crowded with
tubercles, which may become ridge-like; lower face with bold
rounded ridges so anastomosing as to give more or less irregu-
larly reticulate effect; spore range is about the same, 290-540 u
as extremes, with 430-540 1 most commonly occurring. A form
in which the megaspores are usually larger (430-540) and the
microspores in the higher range of 30-33 u, then showing spines
quite readily, might be distinguished (Haton 832 and 337, Curtiss
3813, Mo. Bot. Gard. Herb.).

Distribution: Georgia, Florida.

Specimens examined:

Georgia: in sluggish pine-barren stream, Bulloch Co., partly
emersed, 10 June, 1901, Harper 843 (U.S. Nat. Herb.) ; in
sluggish pine-barren stream, partly emersed, Bulloch Co.,
26 June, 1901, Harper 951 (Mo. Bot. Gard. Herb., U. S. Nat.
Herb., Gray Herb., and N. Y. Bot. Gard. Herb.) ; in cypress
pond near Cobb, Sumter Co., 11 July, 1901, Harper 1046
(Mo. Bot. Gard. Herb., Gray Herb., U. S. Nat. Herb., and
N. Y. Bot. Gard. Herb.).

Florida: open miry places in Turnbull Swamp, Halifax River,
May, Curtiss 3813 (Mo Bot. Gard. Herb.) ; margin of shaded
pond, Riverland, Sumter Co., 23 July, 1900, Curtiss 6696
(Mo. Bot. Gard. Herb. and N. Y. Bot. Gard. Herb.) ; Miami
River and Everglades, Dade Co., 17 November, 1903, Eaton

(Vol. 9
138 ANNALS OF THE MISSOURI BOTANICAL GARDEN

337 (Mo. Bot. Gard. Herb.) ; muddy alligator hole at Goss-
man’s, Dade Co., 25 February, 1905, Haton 1244 (Mo. Bot.
Gard. Herb.); Fort Ogden, De Soto Co., 31 March, 1905,
Eaton 1455 (Mo. Bot. Gard. Herb.); without locality or
date, Haton 832 (Mo. Bot. Gard. Herb.).

The characteristic on which Small named the species J. alata,
namely, prominent wings in the lower parts of the leaves, is apt
to be found in any large-bulbed form, where the leaf bases be-
come broad. In regard to the spore markings, it is possible to
find transitional material (Harper 1046).

32. I. Lechleri Mett. Fil. Lechler. 2: 36. 1859; A. Br. Verh.
Bot. Ver. Brandenb. 4: 331. 1862; Baker. Jour. Bot. 18: 68.
1880, and Fern Allies, 126. 1887; Motel. & Vendr. Actes Soc.
Linn. Bord. 36: 357. pl. 15. fig. 1-2. 1883.

Calamaria Lechlert Kuntze, Rev. Gen. Pl. 2: 828. 1891-93.

T. socia A. Br. Verh. Bot. Ver. Brandenb. 4: 332. 1862.

I. Karstenu A. Br. Verh. Bot. Ver. Brandenb. 4: 332. 1862.

Corm 2-lobed; leaves 5-15, 4 em. long, medium fine, tapering
to point, from base widened by membranous sheath; peripheral
strands none; stomata fairly numerous; sporangia 3-4 mm. long;
velum complete; megaspores white, 380-440 p in diameter, with
roughened surface, marked by very low tuberculate and serpen-
tine elevations; microspores ashy brown, 30-86 yp long, markedly
spinulose.

Distribution: Argentina.

Specimen examined:

Argentina: Province of Cordoba, 2 February, 1887, Hieronymus
774 (U.S. Nat. Herb.).

This specimen is labeled by Hieronymus as J. socia A. Br.,
which is but a form of J. Lechleri Mett. according to Braun, who
at the same time described J. Karstenii, which seems to fit this
plant a little better because of spinulose microspores. Braun
reduced both species to J. Lechleri, widening its range.

33. I. triquetra A. Br. Verh. Bot. Ver. Brandenb. 4: 332.
1862; Motel. & Vendr. Actes Soc. Linn. Bord. 36: 325. 1883.

Calamaria triquetra Kuntze, Rev. Gen. Pl. 2: 828. 1891-983.

I. Andina Spruce in Motel. & Vendr. Actes Soc. Linn. Bord.

PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 139

36: 325. 1883.

Corm 2-lobed; leaves 6-100, coarse, erect, form abruptly
pointed, triangular in cross-section; stomata and peripheral
strands lacking; sporangia oblong, truncate, hardly spotted;
velum lacking; megaspores inconspicuously tuberculate above,
distinctly in center of basal part; microspores smooth, brown or
white.

Distribution: South America, Peru.

This description is derived from a combination of characters
given by A. Braun and Motelay & Vendryés.

34. I. Howellii Engelm. Trans. St. Louis Acad. Sci. 4: 385.
1882; Underwood, Native Ferns and Fern Allies, 124. 1882;
Eaton, Fern Bull. 8: 32-33. 1900; Piper and Beattie, Fl. Wash.
8. 1914.

I. nuda Engelm. Trans. St. Louis Acad. Sci. 4: 385. 1882.

I. Underwoodi Hend. Bot. Gaz. 23: 124. 1897.

I. melanopoda var. californica A. A. Eaton in Gilbert, List
N. Am. Pterid. 10: 27. 1901.

Corm 2-lobed; leaves 10-30, rarely 50, 5-24 em. long, bright
green, erect or slightly outspread, slender (less so in emersed
forms), with wide membranaceous margin extending 1-5 cm.
above sporangium level, sometimes abruptly narrowed; stomata
numerous; peripheral strands usually 4, sometimes 1 or more
lacking; ligule narrow, elongated triangular; sporangia orbicular
to oblong, 3-6, rarely 8, mm. long, frequently brown-spotted,
partially covered by velum, up to 1/3; megaspores white, 420—
520 u in diameter, more or less obscurely marked with simple
tubercles to short crests, isolated or anastomosing, sometimes
crowded, sometimes distant; microspores 25-33 yu long, chiefly
27 u, smoothish to short spinulose.

Distribution: W. Montana, Idaho, Washington, Oregon, Cali-
fornia.

Specimens examined:

Montana: 3000 ft. alt., Bigfork, Flathead Co., 14 August, 1909,
Jones (Mo. Bot. Gard. Herb.); border of Swan Lake, 15
August, 1901, Umbach (U.S. Nat. Herb.).

Idaho: in wet places along Paradise Creek, Moscow, 11 June,
1895, Henderson 2894 (U.S. Nat. Herb.) ; wet ground about
pools, Paradise Creek, Moscow, without date, Henderson

[Vol 9
140 ANNALS OF THE MISSOURI BOTANICAL GARDEN

(N. Y. Bot. Gard. Herb.) ; low soil, forks of St. Mary’s River,
alt. 1000 m., 3 July, 1895, Leiberg 1149 (U.S. Nat. Herb.) ;
growing in water, pools near Moscow, but maturing macro-
spores and microspores in mud, 24 June, 1897 and 30 July,
1898, Henderson (Gray Herb.) ; about forest, Nez Perces Co.,
alt. 3500 ft., 30 July, 1896, A. A. & E. Gertrude Heller 3482
(Mo. Bot. Gard. Herb., U. S. Nat. Herb., and Univ. Minn.
Herb.); in mud, Warrens Meadows, Eastern Latah Co., 2
July, 1898, Henderson 2978 (Mo. Bot. Gard. Herb.) ; in water
or mud, Moscow, 24 June and 2 August, 1898, Henderson
(Mo. Bot. Gard. Herb.) ; Moscow, 30 May, 1837, Henderson
2894 (Mo. Bot. Gard. Herb.) ; wet shores, Lake Coeur d’Al-
ene, alt. 650 m., 1 October, 1895, Leiberg 1656 (U.S. Nat.
Herb.); wet shores of Lake Pend d’Oreille, alt. 650 m., 2
October, 1895, Leiberg 1663 (U.S. Nat. Herb.) ; lake shore,
Sand Point, 24 August, 1901, Umbach (U. 8. Nat. Herb.).

Washington: near Spangle, Spokane Co., 28 June, 1884, Suks-
dorj 2369 (Mo. Bot. Gard. Herb.); in slow shallow stream,
Falcon Valley, 30 July, 1885, Suksdorf 833 (Mo. Bot. Gard.
Herb. and U. 8. Nat. Herb.) ; in slow shallow stream, Falcon
Valley, 6 September, 1886, Suksdorf 2370 (Mo. Bot. Gard.
Herb.) ; in mud in shallow water, becoming dry in summer,
Spokane Co., 10 June and 11 July, 1889, Suksdorf 950
(Mo. Bot. Gard. Herb. and U. S. Nat. Herb.) ; Rock Creek,
near Mica Peak, Spokane Co., 5 June, 1889, Suksdorf 2368
(Mo. Bot. Gard. Herb.); near Rockland, Klickitat Co., 15
April, 1890, Suksdorf 1235 (Mo. Bot. Gard. Herb.); in a
ditch, Faleon Valley, 30 July and 16 October, 1895, Suksdorf
2372 (Mo. Bot. Gard. Herb.); Falcon Valley, Klickitat Co.,
16 July, 1896, Suksdorf 2613 (Mo. Bot. Gard. Herb.); in
shallow water, Falcon Valley, 16 July, 1896, Suksdorf 2479
(Mo. Bot. Gard. Herb.) ; Falcon Valley, 28 June, 1898, Suks-
dorf 2616 (Mo. Bot. Gard. Herb.) ; Rockland, Klickitat Co.,
10 May, 1899, Suksdorf 2618 (Mo. Bot. Gard. Herb.) ;
muddy banks of Pend d’Oreille River near Cusick, 21 Sep-
tember, 1903, Piper 4209 (Mo. Bot. Gard. Herb. and U. S.
Nat. Herb.).

Oregon: on the borders of ponds, The Dalles, 1 June and 1
August, 1880, J. & T. J. Howell (Mo. Bot. Gard. Herb. and
U. S. Nat. Herb.), typz; The Dalles, October, 1880, T. J.

PFEIFFER—MONOGRAPH OF THE ISOETACEAE 141

Howell (Mo. Bot. Gard. Herb. and U. S. Nat. Herb.); The
Dalles of the Columbia, 11 October, 1881, Pringle (Mo. Bot.
Gard. Herb. and U. 8. Nat. Herb.) ; Hood River, May, 1882,
T. J. Howell (N. Y. Bot. Gard. Herb.) ; The Dalles, in small
ponds, 20 May, 1882, T. J. Howell (Mo. Bot. Gard. Herb.) ;
shallow pond 14 miles below The Dalles, 21 May, 1882, T. J.
Howell (Mo. Bot. Gard. Herb.) ; nearly submerged in small
ponds, Hood River, 22 May, 1882, T. J. Howell (Mo. Bot.
Gard. Herb. and U. S. Nat. Herb.); Hood River, 3 July,
1891, T. J. Howell 1521 (Mo. Bot. Gard. Herb., U. S. Nat.
Herb., and Univ. Mimn. Herb.); im small ponds at The
Dalles, May, 1895, T. J. Howell 698 (Mo. Bot. Gard. Herb.) ;
near Dalles City, 4 May, 1898, Suksdorf 2617 (Mo. Bot.
Gard. Herb.); in or near shallow water near Dalles City,
Wasco Co., 7 June, 1904, Suksdorf 642 (Mo. Bot. Gard.
Herb.) ; shallow water on shore of Rogue River, near Soli-
tude Bar, 26 June, 1917, Nelson 1531 (Gray Herb.); com-
pletely submerged in standing water along S. P. tracks, 3
mi. south of Salem, 27 June, 1921, Nelson 3939 | (Mo. Bot.
Gard. Herb.); bottom of dried-up pwol, along S. P. tracks,
3 mi. south of Salem, 16 July, 1921, Nelson 4059 (Mo. Bot.
Gard. Herb.).

California: in shallow water, gravel, submerged, growing singly,
Bear Valley, San Bernardino Mt., alt. 7000 ft., August, 1882,
S. B. & W. F. Parish 1440 (Mo. Bot. Gard. Herb. and U. S.
Nat. Herb.); m dry beds of shallow ponds, Olema, June,
1886, Curran (Mo. Bot. Gard. Herb.); Priest Valley, Mont-
erey Co., 13 May, 1893, Miss Eastwood (Mo. Bot. Gard.
Herb.) ; El Cajon, April, 1895, Brandegee (Mo. Bot. Gard.
Herb.) ; on sand meadow, elev. 9000 ft., south fork Kaweah
River, Tulare Co., 1 August, 1895, Dudley 1043 (Dudley
Herb.); in a pond, near Hyampom, Trimity Co., 10 June,
1896, Howe & Blasdale (Mo. Bot. Gard. Herb.); growimg
wholly or partially submerged m pond near Hyampom,
Trinity Co., 10 June, 1896, Howe (N. Y. Bot. Gard. Herb.) ;
in a marsh about a mile from Olema, Marin Co., 4 July, 1896,
Miss Eastwood (Mo. Bot. Gard. Herb., Gray Herb., U. S.
Nat. Herb., Univ. Mimn. Herb.) ; pools in the plams, Chap-
man’s, Mariposa Co., 27 April, 1897, Congdon 91 (Gray
Herb.); Powder Mill Canyon, Santa Cruz, 25 May, 1900,

(Vol. §$
142 ANNALS OF THE MISSOURI BOTANICAL GARDEN

Thompson (Mo. Bot. Gard. Herb.); Powder Mill Canyon,
Santa Cruz, 9 May, 1901, Mrs. C. H. Thompson (Mo. Bot.
Gard. Herb. and Univ. Minn. Herb.) ; in a winter pond hole,
elev. 2000 ft., near Burnett Creek, Monterey Co., 4 April,
1901, Dudley (Mo. Bot. Gard. Herb.); Woodside Valley
pond, San Mateo Co., 31 October, 1909, Dudley (Dudley
Herb.) ; common locally in shallow edges of sloughs, Chico,
Butte Co., 30 May, 1903, Copeland 3281 (Mo. Bot. Gard.
Herb., Gray Herb., and U. 8. Nat. Herb.) ; Coal Mine Ridge
Ponds, Santa Cruz Mountains, 28 May, 1906, McMurphy
(U. S, Nat. Herb.); edge of pond west of Scofield Pond,
Coal Mine Ridge, 26 June, 1908, Dudley (Dudley Herb.) ;
Coal Mine Ridge, 26 May, 1910, Dudley (Dudley Herb.) ;
Coal Mine Ridge, San Mateo Co., 19 May, 1906, McMurphy
(Dudley Herb.).

Lower California: Sierra El Taste, November, 1902, Brandegee
(Mo. Bot. Gard. and U. 8. Nat. Herb.).

The material collected by Brandegee at El Cajon, Cal., April,
1895, and at Sierra El Taste in November, 1902, is unusual for
I. Howellii in the small spore size. The former has characteris-
tic markings, has megaspores 860400 u in diameter (26-30 u
for microspores). The latter has megaspores 360-400 » (26-30 u
for microspores), smoothish to lightly tuberculate, recalling some-
what J. mexicana but more nearly resembling J. Howelli in habit.
Both are placed here provisionally, since the size of plant accords
well and is too large for the var. minima with which the spore
size would place these specimens.

Nelson’s numbers 3939 and 4059 represent somewhat aberrant
forms in the degree of development of the ridges on the mega-
spores, and in the long leaves (20-35 em.), but they seem to fall
within the range of J. Howellii rather than to be separable as a
new form.

34a. Var. minima Pfeiffer, comb. nov.

I. minima Eaton, Fern Bull. 6: 30. 1898.

Corm 2-lobed; leaves 7-16, 3-6 (sometimes 8-10) cm. long,
fine, somewhat spreading, attenuate at tip; stomata present;
peripheral strands usually 4, weak; ligule triangular, slightly
elongated; sporangium 2-3 mm. in length, about 1/3 covered
by velum; megaspores white, 320-420 u in diameter, marked

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAB 143

with vague short crests, tubercles, like species; microspores 23-

30 py, rarely 33 py, in length, almost smooth to spinulose.

Distribution: Washington, California, Lower California.

Specimens examined:

Washington: in a slow shallow stream, Falcon Valley, 6 Septem-
ber, 1886, Suksdorf 2371 (Mo. Bot. Gard. Herb.); damp
places on prairies near Waverley, Spokane Co., 16 May, 1889,
Suksdorf 2365, 2366 (Mo. Bot. Gard. Herb.) ; on wet ground
near Spangle, Spokane Co., May, 1889, Suksdorf 2367 (Mo.
Bot. Gard. Herb.).

California: San Diego, May, 1903, Orcutt (Mo. Bot. Gard. Herb.
not U.S. Nat. Herb., same date and place).

Lower California: Sierra de la Laguna, 23 January, 1890, Bran-
degee 674 (Gray Herb.).

The form differs from the type species in its smaller size, not
only in leaf length and thickness, but also in megaspores and
microspores.

A. A. Eaton founded his species J. minima on a 3-lobed speci-
men of this form. Since most of the material cited proves to
be 2-lobed, it is supposed that the occurrence of 3 lobes is like
the chance development reported occasionally in other regularly
2-lobed species.

35. I. Bolanderi Engelm. Am. Nat. 8: 214. 1874; Baker,
Jour. Bot. 18: 68. 1880; Motel. & Vendr. Actes Soc. Linn. Bord.
36: 338. 1883; Engelm. in Brewer & Watson, Bot. Cal. 2: 350.
1880; Coulter, Bot. Rocky Mts. 435. 1885; Engelm. Trans. St.
Louis Acad. Sci. 4: 381. 1881; Macoun, Cat. Canad. Pl. pt.
4: 293. 1888; Piper, Contr. U.S. Nat. Herb. 9: 89. 1906; Coul-
ter & Nelson, Bot. Rocky Mts. 25. 1909.

Calamaria Bolanderi Kuntze, Rev. Gen. Pl. 2: 828. 1891-93.

I. californica Engelm. in Gray, Manual, ed. 5, 677. 1867.

I. Bolanderi var. Parry: Engelm. Am. Nat. 8: 214. 1874.

I. Bolanderi Sonnei Hend. Bull. Torr. Bot. Club 27: 349. 1900.

Corm deeply 2-lobed; leaves 6-25, 6-13 cm. long, rarely 25
cm., slender, tapering to a very fine point, bright green, soft;
stomata not numerous; peripheral strands usually lacking; ligule
small, cordate; sporangia 3-4 mm. long, about 1/4-1/3 covered
by velum; megaspores white, sometimes bluish, 300-440 u, rarely

; [Vol. 9
144 ANNALS OF THE MISSOURI BOTANICAL GARDEN

480 u, in diameter, obscurely or more distinctly marked with low
tubercles or wrinkles; microspores 23-30 long, more or less
spinulose.

Distribution: Idaho, Wyoming, Colorado, Utah, Arizona, Bri-
tish Columbia, Washington, Oregon, California.

Specimens examined:

Idaho: Bitter Root Forest Reserve, alt. 2050 m., 26 August,
1897, Leiberg 39 (Mo. Bot. Gard. Herb.); head of Bear
Creek, Bitter Root Forest Reserve, alt. 2050 m., 26 August,
1897, Leiberg 2939 (U.S. Nat. Herb.).

Wyoming: shallow pond near falls of Yellowstone River, 1873,
Parry 307 (Mo. Bot. Gard. Herb., N. Y. Bot. Gard. Herb.,
and Gray Herb.) ; Yellowstone Park, June, September, 1885,
Tweedy 417 (U.S. Nat. Herb.); ponds, Snake River, 9000
ft., August, 1897, Tweedy 362 (N. Y. Bot. Gard. Herb.) ;
Yellowstone Lake, 12 August, 1897, Rydberg & E. A. Bessey
3520 (U. 8. Nat. Herb., N. Y. Bot. Gard. Herb., and Gray
Herb.) ; Yellowstone Park, 4 August, 1902, Mearns 2807 (U.
S. Nat. Herb.); entirely submerged in shallow pond cut off
from north end of Yellowstone Lake, 16 August, 1900, C. £#.
Bessey 2 (N. Y. Bot. Gard. Herb.).

Colorado: ponds in Elk Mts., 1881, Brandegee 2001 (Mo. Bot.
Gard. Herb.) ; lake in Gunnison River Valley, 10,900 ft. alt.,
lakes near timber line, main range, Routt Co., September,
1891, Trelease (Mo. Bot. Gard. Herb.); (probably) sub-
merged on coarse granite bottom, Ward, Boulder Co., alt.
2500 m., Clokey (Schmoll) 3986 (Mo. Bot. Gard. Herb.).

Utah: subalpine lake, Alta, Wasatch Mts., 12 August, 1879,
Jones (Mo. Bot. Gard. Herb. and U. 8. Nat. Herb.); Alta,
Wasatch Mts., August, 1883, Jones (N. Y. Bot. Gard. Herb.).

Arizona: in a lake about 2 miles east of Tunnel Road, Black Mesa
Forest Reserve, 1 June, 1900, Coville 1053 (U. S. Nat.
Herb.).

British Columbia: Indian Reservation, Kamloops, 29 June, 1889,
John Macoun 14212 (Gray Herb.) ; in 6 feet of water, Lake
Mara, Sicamous, 7 July, 1889, J. Macoun (N. Y. Bot. Gard.
Herb.).

Washington: ponds, alt. 6300 ft., Cascade Mts., August, 1882,
Tweedy (Mo. Bot. Gard. Herb. and N. Y. Bot. Gard. Herb.) ;

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 145

lakes of Cascade Mts., October, 1882, Brandegee (Mo. Bot.
Gard. Herb.) ; ponds, Mt. Paddo (Adams), August, 31 Oc-
tober, 1881, Suksdorf (Mo. Bot. Gard. Herb. and U. S. Nat.
Herb.) ; Mt. Adams, 12 August, 1882, Thos. Howell (N. Y.
Bot. Gard. Herb.) ;. Mt. Adams, alt. 6000 ft., 21 August,
1886, Suksdorf 2375 (Mo. Bot. Gard. Herb.).

Oregon: Alpine, eastern Oregon, 1886, Cusick 1451 (Gray Herb.) ;
Gayhart Buttes, alt. 2250 m., 7 August, 1896, Coville &
Leiberg 271 (U.S. Nat. Herb.) ; in a pond, Flag Basin, Bear
Creek watershed, Wailowa Mts., 9 September, 1907, Coville
2483 (U.S. Nat. Herb.).

California: small lakes, Cisco, Sierra Nevada, June, 1870, Bolan-
der (Mo. Bot. Gard. Herb.) ; near Mono trail, alt. 10,000 ft.,
1866, Bolander 5093 (Mo. Bot. Gard. Herb. and U. S. Nat.
Herb.); Upper Tuolumne River, little pools, alt. 9000-
10,000 ft., 1866, Bolander 5091 (Mo. Bot. Gard. Herb. and
U.S. Nat. Herb.) ; Mt. Dana, alt. 10,000 ft., 1866, Bolander
5080 (Mo. Bot. Gard. Herb.); Mary’s Lake, near summit,
alt. 7000 ft., June, 1870, Bolander (Mo. Bot. Gard. Herb.) ;
Ice Lake near Soda Spring station, Sierra Nevada, alt. 7500
ft., 11 October, 1880, Hngelmann (Mo. Bot. Gard. Herb.
and U.S. Nat. Herb.); lakes, Summit Valley, alt. 7500 ft.,
20-22 September, 1882, Pringle (Mo. Bot. Gard. Herb., Gray
Herb., and N. Y. Bot. Gard. Herb.); Webber Lake, Sierra
Co., Lemmon (Mo. Bot. Gard. Herb. and Gray Herb.) ; Lake
Tahoe, May, 1889, Lemmon (Mo. Bot. Gard. Herb.) ; pond
about 2 miles southwest of Whitney Meadows, Sierra Ne-
vada, Tulare Co., 26 August, 1891, Coville & Funston 1722
(N. Y. Bot. Gard. Herb. and U. 8S. Nat. Herb.) ; in pool on
mountainside northwest of Whitney Meadows, Sierra Ne-
vada, Tulare Co., 20 August, 1891, Coville & Funston 1643
and 1650 (U.S. Nat. Herb.); same station, Coville & Fun-
ston 1643 (Gray Herb. and N. Y. Bot. Gard. Herb.) ; about
4 miles northwest of Whitney Meadows, Sierra Nevada,
Tulare Co., 25 August, 1891, Coville & Funston 1691 (U.S.
Nat. Herb. and N. Y. Bot.| Gard. Herb.); Sierra Nevada,
1883, Parry (U.S. Nat. Herb.) ; Ice Lake (abandoned), Sum-
mit, Placer Co., 26 September, without year, Kellogg (U. S.
Nat. Herb., N. Y. Bot. Gard. Herb., and Mo. Bot. Gard.
Herb.) ; Donner Lake, September, 1887, Curran (Mo. Bot.

Gard. Herb. and U. & Nat. Herb.); below Double Peak,
Yosemite National Park, 6 August, 1919; Clemens 2 (U.
S Nat. Herb.); above Dog Lake, Yosemite National Park,
30 July, 1919, Clemens 1 (U.S. Nat. Herb.).
the characters distinguishing them seem either meonsiant or not
true morphological differences. Material from Yellowstone Lake,
described as I. Bolandert v. Parryi Engelm. falls well withm the
leaves, apparent absence of stomata, almost orbicular macrospo-
covers from 1/3 to 2/3 of the sporangmmm..” has not been available
for study, but every pomt mentioned 1s the sort m which one an-
tieapates wartsizon withm amy Isoetes species. For this reason,
im addiizon to the similarity m locality, Donner Lake, Cal, from
which specimens were examined that proved to be I. Bolander,
the wamety Somme: is here reduced.

3352. Var. pysmeea Cinie Fem Allies 228 258 1905.

I_ pwgmoecs Engeim. Am. Nat. 8: 214. 1874

Calamaria pygmoea Kunize, Rev. Gen. Pl 2: 828. 1891-93.

Comm deeply 2lobed: leaves few (3-15), 2-25 am. long, stout,
ftapermg but rather abrupily narrowed to the apex, with con-
spicnous membrznous margms develope’ only to upper level of
sporsngium ; stomazi2 and peripheral strands lackmg; ligule small,
trmameular; sporangmmm small, orbicular, partly covered by very
nazrow velum ; mezzspores white, 360-500 u im diameter, smooth-
ish or indistinctly marked with short wrmkies and tubereles, low
and round im sthouciie: microspores 26-30 yu, smooth to shghily

Distribution: Nevada, Armona, California.
Speamens examined -
Nevadz: floating m Walker Lake, brought down from Mono Pass
above, 14 August, 1898, Congdon 991 (Gray Herb.).
Aroma: Huachues Mis_ So. Arizona, Lemmon (Mo. Bot. Gard.
Herb).
Califormiz- Momo Pass, eastern declivity of Sierra Nevada, alt.
6000 ft_ September, 1866, Bolander 6025 (Mo. Bot. Gard.

PFEIFFER—MONOGRAPH OF THE ISOHTACEAE 147

Herb.), TrPz; Mono Pass, in deep water, Bolander 6333 (U.
S. Nat. Herb.)-

There are two sheets of material, one with 2 single specimen,
the other with two plants, m Mo. Bot. Gard. Herb., from Engel-
mann’s herbarium. The appearance of the leaves is not at all
that of I. Bolanderi, since they are very short and taper markedly
from a wide margin occurring at the sporangium level, but the
spore characters are very similar to [. Bolamderi. Additional
material from U. S. Nat. Herb. shows the same stout
leaves, with almost setaceous tips, and is probably from the same
collection as the type 6025.

36. L Tuerckhemma Brause m Urban, Symb. Antillamze T-

161. 1912.

Corm 2-lobed; leaves 10-31, 5-10.5 em. long, slender, grad-
ually tapering to apex, with narrow membransceous margin ex-
tending only to level of top of sporangimm ; stomata at tip of leaf;
peripheral strands none; ligule short-triangular, cordate at eee
sporangia globose to oblong, 34 mm. long, about 1/3 covered
by velum; megaspores 410-500 u m diameter, smooth or lightly
marked with rather distant low warts; microspores 26-32 w long,
smooth.

Distribution: Harti.

Specimens examined:

Haiti (St. Domingo) ; near Constanzo m Valle Nuevo, alt. 2200
m., in rock fissures im rivulet, August, 1910, Tiurckhewm
3531 (Mo. Bot. Gard. Herb.. Gray Herb., N. Y¥. Bot. Gard.
Herb., and U. S. Nat. Herb.), trem

Of the available species I. Tuerckhexmu seems to resemble mm
spore characters I. mexicana Underw. It differs m the lack of
peripheral strands and im the very different habitat.

37. L mexicama Underw. Bot. Gaz. 13: 93. 1888.

I. Montezumae Eaton, Fern Bull. 5: 25. 1897.

Corm 2-lobed; leaves 10-30, 7-23, or rarely 30, em. long, fine,
erect, tapering, with membranaceous margim 2-3 times length of
the sporangium; stomata numerous; peripheral strands usually
4; ligule triangular, somewhat elongated; sporangia 3—6 or even
8 mm. long, with very narrow velum; megaspores white, 320-

[Vol. 9
148 ANNALS OF THE MISSOURI BOTANICAL GARDEN

460 u, rarely larger, in diameter, sharply angular in outline, with
faces smooth or marked with large low tubercles; microspores
fawn-colored, chiefly 27-89 » long, mostly spinulose.

Distribution: Chihuahua, Hidalgo, Mexico, Morelos.
Specimens examined:

Mexico: wet places, pine plains, base of Sierra Madre, State of
Chihuahua, 6 October, 1887, Pringle 1447 (U.S. Nat. Herb.
and Gray Herb.), TypE; wet places, base of Sierra Madre,
10 October, 1888, Pringle 1713 (Mo. Bot. Gard. Herb.) ;
Canales Station, State of Hidalgo, 29 September, 1904, Prin-
gle 8796 (Mo. Bot. Gard. Herb., Gray Herb., and U. 8. Nat.
Herb.) ; wet soil, borders of shallow ponds, plains near Flor
de Maria, State of Mexico, 28 August, 1890, Pringle 3459
(Mo. Bot. Gard. Herb. and U. 8. Nat. Herb.) ; shallow pools,
Sierra de las Cruces, alt. 9500 ft., State of Mexico, 24 August,
1904, Pringle 13261 (U.S. Nat. Herb. and Gray Herb.) ;
shallow water near Cuernavaca, State of Morelos, 22 August,
1897, Pringle 6660 (Mo. Bot. Gard. Herb., Gray Herb., and
U.S. Nat. Herb.) ; “torrent qui descende de Monte San Mi-
guel, vers Lama de la Huerta,” alt. 2200 m., vicinity of
Morelia, State Michoacan, 10 November, 1910, Bro. G.
Arséne 3653 (U.S. Nat. Herb.).

The species is variable in habit, ranging to almost terrestrial.
from the appearance of herbarium material. The species I.
Montezumae was based on material collected by Pringle in
the states of Mexico and Morelos. The distinctive difference
in the herbarium specimens lies in the presence of tiny basal
scales in some of this material. Since there is variability in this
feature in other forms, as J. Nuttall A. Br., probably in accord-
ance with the amount of moisture present, and since the
plants growing in shallow water fail to show such persistent
leaf-bases, the character is considered ecological. The species
is accordingly reduced. .

Pringle’s No. 18261 is unusual in showing megaspores as large
as 660 p in diameter, but otherwise agrees with the type. These
were collected from the soil, but spores from the sporangia were
as large as 520 u, outside the range shown by any other material
available.

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 149

38. I. melanopeda Gay & Dur. Bull. Soc. Bot. Fr. 11: 102.
1864; Engelm. Bot. Gaz. 3: 1. 1878; Baker, Jour. Bot. 18: 105.
1880, and Fern Allies, 128. 1887; Motel. & Vendr. Actes Soc. Linn.
Bord. 36: 372. pl. 14. fig. 1-3. 1883; A. A. Eaton in Gray,
Manual, ed. 7, 61. 1908.

I. melanopoda var. pallida Engelm. Trans. St. Louis Acad. Sci.
4: 387. 1882.

Calamaria melanopoda Kuntze, Rev. Gen. Pl. 2: 828. 1891-93.

Corm 2-lobed; leaves 15-60, 15-40 cm. long, slender, erect,
firm, bright green, usually black and shining at base, with usu-
ally pale membranaceous border, little (2-3 em.) extended above
sporangium level; stomata present; peripheral strands 4 or 6
cardinal, plus as many as 14 accessory groups; ligule subulate tri-
angular; sporangia oblong, 0.5-3 em. long, marked by numerous
brown spots; velum variable, from very narrow to covering 1/2
of sporangium; megaspores 280-440 up in diameter, marked with
low tubercles, frequently confluent into short low wrinkles; mi-
crospores frequently ashy-gray, 20-30 u long, fine spinulose.

Distribution: Illinois, Missouri, Iowa, Oklahoma, and Texas.

Specimens examined:

Illinois: Ringwood, 1863, Vasey (Mo. Bot. Gard. Herb. and Gray
Herb.) ; wet meadows, without date, Hall (Gray Herb.);
shallow border of pond, near Wady Petra, Stark Co., 30
June, 1898, Chase 86 (Mo. Bot. Gard. Herb.); drying bed
of shallow pond near Wady Petra, 26 July, 1898, Chase 136
(Mo. Bot. Gard. Herb.); Athens, Menard Co., Hall (Gray
Herb.) ; Athens, 1861, Hall (Gray Herb.); Athens, Septem-
ber, 1861, Hall (U.S. Nat. Herb.) ; ponds, Athens, Menard
Co., July, 1868, Dement (Mo. Bot. Gard. Herb.); from
small pond, in water, 6 inches deep, Athens, Menard Co., 3
June, 1865, Hall (Mo. Bot. Gard. Herb.); pond dry for
several days, Athens, 18 June, 1865, Hall (Gray Herb.) ;
Athens, 27 June, 1865, Hall (Mo. Bot. Gard. Herb. and Gray
Herb.); “wet prairies, shallow ponds, now dry, in spring
under water,” 19 June, 1865, Athens, Hall (Mo. Bot. Gard.
Herb. and U.S. Nat. Herb.) ; Athens, 30 October, 1865, Hall
(Mo. Bot. Gard. Herb.); Athens, second crop, in water, 3
November, 1865, Hall (Gray Herb.) ; Athens, 25 November,
1865, Hall (Mo. Bot. Gard. Herb.) ; “second crop,” Athens,
18 November, 1865, Hall (Mo. Bot. Gard. Herb.) ; Athens, 1

[Vol. 9
150 ANNALS OF THE MISSOURI BOTANICAL GARDEN

June and October, 1866, Hall (Mo. Bot. Gard. Herb.) ; Ful-
ton Co., 1874, Wolf (Gray Herb.); “cultures in Jardin
botanique de Bordeaux” sent from Athens by Hall, 2 August,
1876, ex Herb. Motelay (Mo. Bot. Gard. Herb.) ; Athens, 23
June, 1878, Hall (Mo. Bot. Gard. Herb.); Athens, 8 July,
1878, Hall (Mo. Bot. Gard. Herb.); Bluffs Lake, St. Clair
Co., June, 1881, Eggert (Mo. Bot. Gard. Herb., U. S. Nat.
Herb., and Univ. Minn. Herb.); Bluffs Lake, St. Clair Co.,
15 June, 1882, Eggert (Mo. Bot. Gard. Herb. and Univ.
Minn. Herb.) ; Bluffs Lake, St. Clair Co., 22 June, 1882, Eg-
gert (Mo. Bot. Gard. Herb.); “banks of a pond, East St.
Louis,” St. Clair Co., 9 August, 1882, Eggert (Mo. Bot.
Gard. Herb.) ; “Illinois, August,” Mrs. J. M. Milligan (U.S.
Nat. Herb.).

Iowa: Clinton, 1863, Vasey (Mo. Bot. Gard. Herb. and Gray
Herb.).

Missouri: wet prairies, Little Blue River near Courtney, Jackson
Co., 6 July, 1898, Bush (Mo. Bot. Gard. Herb.); Jackson
Co., wet dogwood flats, uncommon, 6 July, 18938, Bush 441
(Gray Herb.) ; Little Blue, Jackson Co., 24 May, 1896, “un-
common,” Bush 746 (Mo. Bot. Gard. Herb.); along, and in,
ditches near Little Blue, east of Independence, ‘very local
and rare,” 24 May, 1896, Bush (Mo. Bot. Gard. Herb.) ;
uncommon on low prairie, Dodson, Jackson Co., 2 May, 1897,
Bush 267 (Mo. Bot. Gard. Herb. and Univ. Minn. Herb.) ;
common in swale, Dodson, 28 June, 1898, Bush 35 (Mo. Bot.
Gard. Herb., Gray Herb., and U. 8. Nat. Herb.) ; common on
limestone ledges, Eagle Rock, Barry Co., 3 June, 1897, Bush
107 (Mo. Bot. Gard. Herb.); Lake City, Jackson Co.,
Mackenzie (Univ. Wyoming Herb.) ; right bank of St. Fran-
cois River, below mouth of Stout Creek, Madison Co., 25
May, 1918, Greenman 3861 (Mo. Bot. Gard. Herb.) ; springy
bank of St. Francois River, near entrance of Stout Creek, 25
May, 1918, Pfeiffer 21 (Mo. Bot. Gard. Herb.).

Oklahoma: “overflowed places,” Limestone Gap, early June,
1875, Butler (Mo. Bot. Gard. Herb.) ; low wet places in al-
kali flats, Limestone Gap, 26 May, 1877, Butler (Mo. Bot.
Gard. Herb.); pools, Limestone Gap, 14 June, 1877, Butler
(Mo. Bot. Gard. Herb.) ; “alluvial deep shade in the bed of
a dried-up stream,’ Limestone Gap, 16 June, 1877, Butler

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 151

(Mo. Bot. Gard. Herb.); pools 1144 mi. north of Limestone
Gap, 8 July, 1877, Butler (Mo. Bot. Gard. Herb. and U. 8.
Nat. Herb.) ; pool by the railroad, Limestone Gap, 10 July,
1877, Butler (Mo. Bot. Gard. Herb. and U. S. Nat. Herb.).

Texas: wet pine-woods, Houston, 20 April, 1872, Hall 859 (Mo.
Bot. Gard. Herb., Gray Herb., and N.Y. Bot. Gard. Herb.) ;
Houston, May, 1872, Hall (Gray Herb.) ; swampy grounds,
Dallas, June, 1877, Reverchon 1177 (U.S. Nat. Herb.) ; wet
sands, Dallas, July, 1880, Reverchon 1177 (Mo. Bot. Gard.
Herb. and U. S. Nat. Herb.); mud, bogs, Buzzards’ Spring
near Dallas, June, 1877, Reverchon 795 (Gray Herb.) ; Buz-
zards’ Spring, 1879, Reverchon (Mo. Bot. Gard. Herb.) ;
dried pond, Sabine River Bottoms, near Mineola, Wood Co.,
2 June, 1903, Reverchon 3561 (Mo. Bot. Gard. Herb.) ; shal-
low ponds, Pine’s Island, Angelina Co., 5 May, 1903, Rever-
chon 3549 (Mo. Bot. Gard. Herb., Gray Herb., and U.S. Nat.
Herb.); Harrisburg, 9 May, 1876, Joor (Mo. Bot. Gard.
Herb.) ; rare in pond, Columbia, 17 October, 1900, Bush 1531
(Mo. Bot. Gard. Herb.) ; Hockley, 1891, Thurow 15 (U.S.
Nat. Herb.).

Although the early material of IJ. melanopoda appeared quite
uniform and therefore the species seemed distinctive, more re-
cent collections tend to add divergent forms. Engelmann early
described a variety pallida, which he based on “larger plants
lacking the black leaf bases of the type, with broader velum and
megaspores in the restricted range of 300-350 u, instead of the
250-400 u range given for the type.” This was based on Texas
collections which upon examination show a wide difference in
spore sizes, running as high as 440 y. These specimens do not
exceed northern forms in leaf number nor in leaf length. More-
over, it frequently happens that pale-based individuals are found
in any stand of J. melanopoda, even though there be a prepon-
derance of dark-based forms. It seems proper, therefore, to con-
sider pallida as a form rather than as a variety of J. melanopoda,
occurring singly or in stands.

There is, moreover, intergrading between two species, in the
case of J. melanopoda and J. Butleri, so that some intermediate
forms are difficult to place accurately. As an illustration, the
examples originally described as J. Butlert var. immaculata com-
bine in remarkable fashion the fine leaf habit of J. Butleri with

[Vol. 9
152 ANNALS OF THE MISSOURI BOTANICAL GARDEN

the greater length of melanopoda and frequently the stronger
bulb development of the latter. The range in spore size is inter-
mediate, overlapping the larger of 7. melanopoda and the smaller
of J. Butleri.

Much of the material representing this form has been collected
in early spring. It is a question whether the fineness of leaves
is related to the early development, as the lack of pigment seems
to be. Certain it is that some stations have yielded only material
labeled “Butleri immaculata” in May, and only “melanopoda”’
in June and July. Whether J. Butleri as found in Oklahoma (In-
dian Territory ) by Butler, owed its characteristic size and fineness
to the alkali flats in which it developed, is another ecological
point worth determining. The series from I. melanopoda devel-
oping in moisture through so-called pallida, in drier surroundings,
to I. Butleri, conceivably might be related to the environment.
Pending further evidence in regard to relation, material showing
the characteristic habit of J. Butleri is placed with that species,
though most of it occurring outside of Oklahoma shows the com-
bination of characters which connect it quite definitely also with
I. melanopoda.

39. I. Butleri Engelm. Bot. Gaz. 3: 1. 1878; Baker, Jour.
Bot. 18: 105. 1880; Motel. & Vendr. Actes Soc. Linn. Bord.
36: 360. 1883; Engelm. Trans. St. Louis Acad. Sci. 4: 388.
1882; A. A. Eaton in Gray, Manual, ed. 7, 61. 1908.

I. Butleri var. immaculata Engelm. Trans. St. Louis Acad.
Sci. 4: 388. 1882.

Calamaria Butleri Kuntze, Rev. Gen. Pl. 2: 828. 1891-93.

Corm 2-lobed; leaves 8-30, 8-15 cm. long, more slender and
rigid than J. melanopoda, tapering to apex; stomata numerous;
peripheral strands usually 4, sometimes more in number; ligule
elongated, cordate at base; sporangium oblong, 6-7 mm. long,
marked with brown lines; velum very narrow; megaspores vari-
able, commonly 480-650 u in diameter, sometimes only 360 u,
marked with numerous tubercles, usually distinct, occasionally
confluent; microspores 27-87 » long, papillose. ’

Distribution: Tennessee, Missouri, Arkansas, Kansas, and
Oklahoma.

Specimens examined:

Tennessee: Cedar Glades, Lavergne, May, Gattinger (N. Y. Bot.

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 153

Gard. Herb.); springy places in cedar barrens, near La-
vergne, Rutherford Co., 7 and 17 May, 1880, Gattinger 3812
(Mo. Bot. Gard. Herb., N. Y. Bot. Gard. Herb., and U. 5.
Nat. Herb.); cedar barrens at Lavergne, 17 May, 1880,
Gattinger (Gray Herb.); springy places in limestone flats
near Nashville, April, 1886, Gattinger (Gray Herb.).

Missouri: common on limestone ledges, Eagle Rock, 3 June,
1897, Bush 107 (Mo. Bot. Gard. Herb., U.S. Nat. Herb., and
Univ. Minn. Herb.); common in barrens, Eagle Rock, 22
May, 1898, Bush 231 (Gray Herb. and N. Y. Bot. Gard.
Herb.) ; common in barrens, Forsyth, 10 June, 1899, Bush 68
(Mo. Bot. Gard. Herb., Gray Herb., U. S. Nat. Herb., and
N. Y. Bot. Gard. Herb.) ; rocky barrens, Noel, 11 May, 1915,
Bush 7547 (Mo. Bot. Gard. Herb., N. Y. Bot. Gard. Herb.,
and Gray Herb.); wet barrens, Swan, 19 May, 1905, Bush
2917 (Mo. Bot. Gard. Herb. and N. Y. Bot. Gard. Herb.) ;
wet barrens, Swan, 17 May, 1907, Bush 4511 (Mo. Bot.
Gard. Herb., Gray Herb., and N. Y. Bot. Gard. Herb.) ;
rocky hillsides} Jefferson Co., 26 May, 1891, Eggert (Mo.
Bot. Gard. Herb., Gray Herb., U. S. Nat. Herb., and Univ.
Minn. Herb.) ; rocky hillside, De Soto, Jefferson Co., 29 May,
1891, Eggert (Mo. Bot. Gard. Herb. and N. Y. Bot. Gard.
Herb.) ; rocky hillside, De Soto, Jefferson Co., 11 and 25
May, 1896, Eggert (Mo. Bot. Gard. Herb. and Univ. Minn.
Herb.) ; De Soto, Jefferson Co., without date, Eggert (N. Y.
Bot. Gard. Herb.); thin black soil on seeping ledges, lime-
stone barrens 4 mi. northwest of Carthage, Jasper Co., 21
April, 1922, Palmer 20848 (Mo. Bot. Gard. Herb.) ; moist
depressions in limestone barrens, near Webb City, Jasper
Co., 29 May, 1922, Palmer 21555 (Mo. Bot. Gard. Herb.).

Arkansas: common in barrens, 8 May, 1902, Bush 1530 (Mo.
Bot. Gard. Herb., N. Y. Bot. Gard. Herb., and U. 8S. Nat.
Herb.); wet barrens near Eureka Springs, 8 May, 1902,
Canby 136 (Gray Herb.).

Kansas: rocky soil, Cherokee Co., May, 1897, Hitchcock 1068
(Mo. Bot. Gard. Herb., U. S. Nat. Herb., Gray Herb., and
N. Y. Bot. Gard. Herb.).

Oklahoma: common on alkali flats, Limestone Gap, Atoka Co.,
first week in June, 1875, Butler (Mo. Bot. Gard. Herb.) ; al-
kali flats near Limestone Gap, 26 and 28 May, 1877, Butler

[Vol. 9
154 ANNALS OF THE MISSOURI BOTANICAL GARDEN

(Mo. Bot. Gard. Herb.) ; flats near Limestone Gap, 13 and
16 June, 1877, Butler (Mo. Bot. Gard. Herb. and U. S.
Nat. Herb.) ; Limestone Gap, 16 June, 1887, Butler 24 (N.
Y. Bot. Gard. Herb.).

Sect. 2. EcHINATAE

§ 2. EcoinatTar. Forms with 2-lobed corms; producing
megaspores with distinct spines; microspores smooth or rough;
peripheral strands lacking; never terrestrial.

Key To SPECIES

A. Stomata absent.
a. Velum narrow, covering less than 14 of spo-
Tanginm (22723 WS Se ee Pe ee _.40. I. echinospora
b. Velum wide, covering 24-34 of sporangium_____-___-___-__-_--
St Seen eee SoS ee 40a. I. echinospora var. asiatica
B. Stomata present.
a. Megaspores with sharp spines,

a. Smaller forms, leaves 3-6 em. in length ~-_---_-- 41. I. Brochom
B. Larger forms, leaves chiefly 8 cm. or
more ‘in. lene tise = n= eee eee ee ee ei 42. I. Braunit
b. Megaspores with blunt spines.
a. Leaves few, 7—15, slender ~-~_----- 42a. I. Braunii var. maritima
fB. Leaves more numerous, 20-40, stout ---------- 43. I. truncata

40. I. echinospora Dur. Bull. Soe. Bot. Fr. 8: 164. 1861; A.
Br. Verh. Bot. Ver. Brandenb. 4: 297. 1862; Babington, Jour.
Bot. 1: 1-5. 1863; Milde, Fil. Eur. 279. 1867; Baker, Jour.
Bot. 18: 67. 1880, and Fern Allies, 125. 1887; Motel. & Vendr.
Actes Soc. Linn. Bord. 36: 334. pl. 9. 1883; Engelm. Trans. St.
Louis Acad. Sci. 4: 379. 1882.

Calamaria echinospora Kuntze, Rev. Gen. Pl. 2: 828. 1891-93.

Corm 2-lobed; leaves 10-40, 5-12 cm. long, pale green,
stout at base, tapering to apex, spreading, recurved, with rather
wide membranaceous margins at base; stomata none; peri-
pheral strands none; ligule deltoid, rather wide at base; spo-
rangia globose or oval, 3-7 mm. long, with very narrow velum;
megaspores white, 440-540 p in diameter, densely echinate with
fine truncate spines, sometimes toothed; commissural ridges ir-
regular in outline; microspores 23-35 in length, rarely 40 uy,
sometimes marked with slight reticulations.

Distribution: British Isles, northern and central Europe.

Specimens examined:

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 155

British Isles: Wales, “In Cambriae lacu Llyn Padark,”’ with
I. lacustris, 30 September, 1862, Gay (Gray Herb.).

Belgium: Genck-Limbourg, 31 July, 1865, ex herb. Thielens
(N. Y. Bot. Gard. Herb.) ; “Belgium,” Le Roy (N. Y. Bot.
Gard. Herb.) ; Etang 4 Genck, prov. Limbourg, August, 1862,
Van den Born (Mo. Bot. Gard. Herb.).

France: Lac de Guery, Puy-de-Dome, 24 August, 1861, Durieu
(Mo. Bot. Gard. Herb.), typz; Lac de Guery, Puy-de-
Dome, 21 September, 1881, Heribaud (N. Y. Bot. Gard.
Herb.) ; Lac de Guery, August, 1890, Hy (Mo. Bot. Gard.
Herb.); Lac St. Andéol, Mt. Aubrac, 23 August, 1861, Gay
(Mo. Bot. Gard. Herb. and Gray Herb.) ; in Longemer, near
Colmar, Vosges, 26 July, 1865, Schlickum (N. Y. Bot. Gard.
Herb.) ;; Gerardmer (Vosges), August, 1867, Martin (Mo.
Bot. Gard. Herb. and U. 8. Nat. Herb.) ; Lac de Longemer,
Vosges, September, 1874, Stahl (Mo. Bot. Gard. Herb.) ;
Lac de Guery, August, 1890, Cosson (Gray Herb.).

Italy: Lago d‘Orta near Busca, Prov. of Novara, 15 September,
1896, Chiovenda (Mo. Bot. Gard. Herb.); Lago d’Orta,
August, 1856, Franzoni (Mo. Bot. Gard. Herb.) ; borders of
‘Jacus Cusii’” (lago d’Orta—Ital. bor.), 1857, Cesatz (Mo.
Bot. Gard. Herb.).

Norway and Sweden: in lakes of Norway, Blytt 1951 (Mo. Bot.
Gard. Herb.); Krigsbergs, Ivarinsbruk, 17 August, 1866,
Duscu (U.S. Nat. Herb.) ; Nerée Gotlunda, 1864, Blomberg
(N. Y. Bot. Gard. Herb.) ; Nyland, Strémfors, 20 July, 1875,
Arrhenius (N. Y. Bot. Gard. Herb.) ; near Stockholm, An-
derssen (Mo. Bot. Gard. Herb.); Vg. Frojered, August,
1880, Junger (N. Y. Bot. Gard. Herb.).

Germany: Feldsee, August, 1846, Brawn (Mo. Bot. Gard. Herb.) ;
Titisee, Schwarzwald, August, 1864, Reess (Mo. Bot. Gard.
Herb. and N. Y. Bot. Gard. Herb.); Titisee near Freiburg,
August, 1864, Solms & Reess (Mo. Bot. Gard. Herb.) ;
Titisee, October, 1863, de Bary (Mo. Bot. Gard. Herb.) ;
Feldsee, Schwarzwald, September, 1861, Thiry (Mo. Bot.
Gard. Herb. and Gray Herb.); Feldsee in Schwarzwald,
1861, ex. Mus. bot. Berol. (U.S. Nat. Herb., 594573) ; Titisee,
August, 1864, Thiry (Gray Herb.) ; Schluchsee (royal forest
of Baden), 1864, Brawn (Gray Herb.) ; Feldsee, 1884, Christ
(N. Y. Bot. Gard. Herb.); im Feldsee, Schwarzwald, 4

[Vol. 9
156 ANNALS OF THE MISSOURI BOTANICAL GARDEN

August, 1881, Study (N. Y. Bot. Gard. Herb.) ; sandy shores
at upper end of the Schluchsee, October, 1861, Schildknecht
& Thiry 799 (N. Y. Bot. Gard. Herb.) ; Titisee, September,
1868, Zickendrath (N. Y. Bot. Gard. Herb.).

Russia: in Livonia, distr. Riga, “in lacu Bule-See”’, 10 September,
1901, Kupffer 14912 (U. S. Nat. Herb.).

AQa. Var. asiatica Makino, Tokyo Bot. Mag. 18: 129. 1904.

Differs from the type in having a broad velum, covering 2/3
to 3/4 of the sporangium, in bearing coarser spinules on the
megaspores, and in the smoothness of the microspores. The
author suggests that it is lacking in stomata by saying that it
differs from J. Braunii which has stomata and a spotted spo-
rangium.

Distribution: rare. Lake Nojiri, Prov. Shinano.

Description from Makino.

41. 1. Brochoni Motel. & Vendr. Actes Soc. Linn. Bord. 45:
45. pl. 2. 1898.

Corm 2-lobed; leaves 8-16, rarely more, 3-6 cm. long, fine,
tapering, rosy below, green above, with short, wide membranace-
ous margin at base; stomata present but not common; peripheral
strands none; ligule very short and broad; sporangium globose,
214-4 mm. long, partially (1/4-1/3) covered by velum; mega-
spores white, 450-525 p in diameter, much flattened in outline,
marked with very echinate, sharply toothed prominences; micro-
spores 33-53 u in length, often nearly as wide.

Distribution: France.

Specimens examined:
France: Lac de Naguilles (1854 m. alt.), Ariege, Motelay (Mo.
Bot. Gard. Herb.), Typz; Lac de Naguilles, August, 1891,
Hy (Mo. Bot. Gard. Herb.).

42. 1. Braunii Dur. Bull. Soc. Bot. Fr. 11: 101. 1864.

I. echinospora var. Braunii Engelm. in Gray, Manual, ed. 5,
676. 1867.

I. echinospora var. Boottu Engelm. in Gray, Manual, ed. 5,
676. 1867.

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 15ST

I. echinospora var. muricata Engelm. in Gray, Manual, ed. 5,
676. 1867.

I. echinospora Brauniu f. Boottu Clute, Fern Allies, 221, 258.

S05.

I. echinospora Brittoni Cockerell, Muhlenbergia 3: 9. 1907.

I. muricata Dur. Bull. Soc. Bot. Fr. 11: 101. 1864.

I. ambigua A. Br. in Engelm. Trans. St. Louis Acad. Sci. 4: 380.
1882.

Corm 2-lobed; leaves usually 10-35, in robust forms 27-55,
8-25 em. long, or rarely longer, straight or recurved, firm, taper-
ing to apex, with rather wide base with membranaceous borders;
stomata present, usually few; peripheral strands none; ligule
deltoid; sporangiaj oblong, spotted, 4-7 mm. long, with velum
14, to completely covering it (western forms of U. 8. have narrow
velum) ; megaspores white, 420-580 u in diameter, marked with
numerous spines ranging from single slender spines to those
toothed or even confluent in short ridges; microspores fawn-
colored, 28-83 » long, smooth to slightly roughened on surface.

Distribution: North America.

Specimens examined:

Greenland: 60°-60° 43’ N. lat., Southern Greenland (‘“Tesser-
mint”), probably about 1825, Jens Vahl (Mo. Bot. Gard.
Herb.) ; Kingua Neriak, 61° 35’, July, 1889, Hartz (Gray
Herb.).

Newfoundland: immersed, sandy soil, Channel, 27 July—1 August,
1901, Howe & Lang 954 (Gray Herb. and N. Y. Bot. Gard.
Herb.) ; small ponds among Siberian Hills back of Birchy
Cove (Curling), region of Humber Arm, Bay of Islands, 11
August, 1910, Fernald & Wiegand 2402 (Gray Herb.) ; bar-
rens at base of the serpentine table-lands, Bonne Bay, 27
August, 1910, Fernald & Wiegand 2405 (Gray Herb.) ; grav-
elly brook in bog, Bishop Falls, 29 July, 1911, Fernald &
Wiegand 4411 (Gray Herb.); shallow pools in bog, Bishop
Falls, Valley of Exploits River, 29 July, 1911, Fernald &
Wiegand 4406 (Mo. Bot. Gard. Herb. and Gray Herb.);
shallow pools in the tundra near Quarry (Laurentian Area
at head of Exploits River System), 23 August, 1911, Fernald
& Wiegand 4401 (Gray Herb.); deep water near center of
middle Birchy Pond (eastern drainage area of Humber
River System), Fernald & Wiegand 2400 (Gray Herb.) ; wet

[Vol. 9
158 ANNALS OF THE MISSOURI BOTANICAL GARDEN

sandy shore of Rushy Pond (Valley of Exploits River), 11
August, 1911, Fernald & Wiegand 4410 (Gray Herb.) ; mud-
dy pool, Killigrew’s (shores of Conception Bay, Avalon Pe-
ninsula), 3 August, 1911, Fernald & Wiegand 4405 (Gray
Herb.) ; diorite tableland, alt. about 550 m., n. region of the
Blomidon (‘“Blow-Me-Down”) Mts., 22 August, 1910, Fer-
nald & Wiegand 2401 (Gray Herb.); Eastern Avalon Pe-
ninsula, bog pond on hill south of St. Johns, 2 August, 1911,
Fernald & Wiegand 4407 (Gray Herb. and U.S. Nat. Herb.) ;
Kitty’s Brook, eastern waters of the Humber River System,
25 August, 1911, Fernald & Wiegand 4403 (Gray Herb.);
shallow pools on serpentine tableland, alt. about 550 m.,
northeast region of the Blomidon Mts., w. Newfoundland,
21 August, 1910, Fernald & Wiegand 2403 (Gray Herb.).

Quebec: Grand Valley, Gaspé, 3 August, 1882, John Macoun
14220 (Gray Herb.); Madeline River, Gaspé, 5 August,
1882, John Macoun 14226 (Gray Herb.); lake near Point
Fame, Gaspé, 5 August, 1882, John Macoun 14224 (Gray
Herb.); Beau Lac, 14 August, 1902, Eggleston 3026 (Gray
Herb., N. Y. Bot. Gard. Herb., and Dudley Herb.) ; alpine
lakes, 900-1000 m., Table-top Mt., Gaspé, 4 August, 1906,
Fernald & Collins 311 (Mo. Bot. Gard. Herb.) ; Lac Fortin,
Table-top Mt., Gaspé, 10 August, 1906, Fernald & Collins
820 (Gray Herb.) ; in muck over granite, Lac 38, Table-top
Mt., Gaspé, 4 August, 1906, Fernald & Collins 316 (Gray
Herb.) ; Lace des Americains, 675 m., western-base Table-top
Mt., Gaspé, 1 and 2 August, 1906, Fernald & Collins 154
(Mo. Bot. Gard. Herb., N. Y. Bot. Gard. Herb., U. S. Nat.
Herb., Gray Herb., and Univ. Minn. Herb.); Granite
Block Pond, alt. 900-1000 m., Table-top Mt., 7 August,
1906, Fernald & Collins 318 (Mo. Bot. Gard. Herb. and
Gray Herb.); Sargent’s Bay, Lake Memphremagog, 3
August, 1908, Churchill (Mo. Bot. Gard. Herb.); Mt. Ele-
phantis Landing, Lake Memphremagog, 14 August, 1903,
Churchill (Mo. Bot. Gard. Herb. and Gray Herb.); pool
(tidal?) at mouth of river, Romaine, Lagorgendiere, Sag-
uenay, 8 July, 1915, St. John 90061 (Gray Herb.) ; growing
at least 5 ft. below surface of water, Lake Pratt, near Riviere
du Loup, July, 1913, Bro. Victorin 61 (Gray Herb.) ; sub-

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 159

merged, Lake MacGregor, 3 August, 1917, Bro. Rolland
6284 (N. Y. Bot. Gard. Herb.) ; Kirck’s Ferry, 16 August,
1916, Bro. Rolland 65 (Mo. Bot. Gard. Herb.); Richelieu
River, Isle Allo-None, 13 August, 1918, Bro. Victorin (N. Y.
Bot. Gard. Herb.); Lake Pratt Co., Temiscouata, August,
1914, Bro. Victorin 694 (Mo. Bot. Gard. Herb., U. S. Nat.
Herb., and Gray Herb.); in 1 ft. water in sandy-bottomed
pond, Petit Riviere Coxipi, Brouage, Saguenay Co., 23 July,
1915, St. John 90059 (Gray Herb.); shallow pool in
tundra, Anse Portage, Archipel de St. Augustin, Saguenay
Co., 5 August, 1915, St. John 90060 (Gray Herb.); 1 ft. of
water, hillside pond, Baie des Moutons, Boishébert, Sag-
uenay Co., 15 August, 1915, St. John 90058 (Gray Herb.).

New Brunswick: Lily Lake, St. Johns, 8 August, 1873, Boott
(Gray Herb.); St. George, Charlotte Co., 17 August, 1883,
Vroom (Gray Herb.); muddy pool on shores of St. John
River, Connors, Madawaska, 13 July, 1903; Pease 2249
(Gray Herb.).

Nova Scotia: Shelburn, August, 1878, James (Mo. Bot. Gard.
Herb.) ; South Ingonish, 8 August, 1898, Macoun (Mo. Bot.
Gard. Herb.) ; Boylston, August, 1890, Hamilton 81051 in
part (Gray Herb.); N. E. Margaree, Cape Breton Isl., 11
August, 1906, Robinson 335 (N. Y. Bot. Gard. Herb.);
(probably) margin of Taylor’s Lake, Sunny Brae, Pictou
Co., 80 July, 1918, St. John 1370 (Gray Herb.); muddy
lagoon, Charcoal, Valley of the East River, Pictou Co., 2
August, 1913, St. John 1371 (Gray Herb.); muddy and
rocky bottom of a quiet brook, New Tusket, 9 August, 1921,
Fernald & Long 23113 (Mo. Bot. Gard. Herb.). |

Maine:

Aroostook Co.: sandy bottom of Beau Lac, 14 August, 1902,
Fernald (Mo. Bot. Gard. Herb.); Beau Lac, 14 August,
1902, Eggleston 3026 (U.S. Nat. Herb.); ledgy margin of
river, St. Francis, 19 August, 1898, Fernald 220 (Mo. Bot.
Gard. Herb., Gray Herb., N. Y. Bot. Gard. Herb., U. S.
Nat. Herb., and Univ. Minn. Herb.); sandy bed of Petti-
quaggimas (Glazier) Lake, 8 August, 1893, Fernald 218 (Mo.
Bot. Gard. Herb.); gravelly margin of River St. Francis,
21 August, 1893, Fernald 219 (Mo. Bot. Gard. Herb., Gray
Herb., U. 8. Nat. Herb., and Univ. Minn. Herb.) ; logan by

[Vol. 9
160 ANNALS OF THE MISSOURI BOTANICAL GARDEN

the river, Fort Kent, 11 August, 1901, Fernald (Gray Herb.) ;
logan in St. Johns River, Fort Kent, 11 August, 1901, Wil-
liams 1 (Gray Herb.); bed of Dyer Brook, Island Falls, 28
August, 1897, Fernald (Gray Herb.); rapids of St. Croix
Stream, Masarde’s, 8 September, 1897, Fernald (Gray
Herb.) ; river margin, Madawaska, 28 July, 1893, Fernald
(Gray Herb.).

Penobscot Co.: Pushaw Pond, August, 1899, F. L. Harvey 2 (Mo.
Bot. Gard. Herb.) ; ledgy margin of Stillwater River, Orono,
4 September, 1893, Fernald y & g (Gray Herb. and N. Y.
Bot. Gard. Herb.) ; Chemo Stream, Bradley, 10 August, 1898,
F. L. Harvey (Mo. Bot. Gard. Herb.) ; submerged, growing
in rock crevices, Chemo Stream, Bradley, 15 July, 1898, F. LZ.
Harvey (N. Y. Bot. Gard. Herb.); Chemo Pond, August,
1897, Merrill (U. S. Nat. Herb.); same, September, 1897
(Gray Herb.); Chemo Stream, Bradley, September, 1897,
Merrill 10 (N. Y. Bot. Gard. Herb.); tidal mud flats at
mouth of Souadabscook Stream, Hampden, 11 September,
1916, Fernald & Long 12341 (Gray Herb. and Mo. Bot.
Gard. Herb.) ; river margin, Mattawamkeag, 14 September,
1898, Fernald 2819 (Gray Herb.); muddy river margin,
Orono, 1 September, 1893, Fernald x (Gray Herb.); tidal
mud flats at the mouth of Reed Brook, Hampden, 8 Sep-
tember, 1916, Fernald & Long 12340 (Gray Herb. and Mo.
Bot. Gard. Herb.); mud in crevices of slate, immersed at
margin of Mud Pond, Oldtown, 29 August, 1908, Fernald
(Gray Herb.).

Washington Co.: margin of Lambert Lake, 1 September, 1908,
Plantae Exsiccatae Grayanae, Fernald (Mo. Bot. Gard.
Herb.) ; granitic gravel and silt at margin of Lambert Lake, 1
September, 1908, Fernald 105 (Gray Herb. and Dudley
Herb.); sandy margin of Pennamaquan River, Pembroke,
18 August, 1909, Fernald 1215 (Gray Herb.) ; muddy bed of
brook, Cutter, 29 August, 1902, Fernald (Gray Herb.).

Hancock Co.: Mt. Desert Isl., Long Pond meadows, Jordan’s
Stream, 26 August, 1891, Rand (N. Y. Bot. Gard. Herb.) ;
bog hole, Long Pond Meadows, 20 September, 1838, Rand
(Gray Herb.); “Mt. Desert Isl.,” Rand (Mo. Bot. Gard.
Herb.) ; in clay mud, beach, southeast end of Great Pond, 19
September, 1898, Rand (Gray Herb.); stream, meadow

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 161

north of Long Pond, Seal Harbor, 21 August, 1889, Rand
(Gray Herb.) ; brook, Long Pond Meadows, Seal Harbor, 21
August, 1889, Redfield 2530 (Mo. Bot. Gard. Herb. and
Gray Herb.); muddy pond, Long Pond meadows, 9 Sep-
tember, 1899, Rand (Gray Herb.).

Piscataquis Co.: Milo, 2 September, 1897, Fernald (Mo. Bot.
Gard. Herb. and Gray Herb.); Mt. Katahdin, September,
1898, Merrill 1408 (U. S. Nat. Herb.); mostly submerged,
Three Ponds, Mt. Katahdin, alt. 1500-1800 ft., September,
1898, Merrill (N. Y. Bot. Gard. Herb.) ; Mt. Katahdin, 15-30
August, 1902, Cowles & Harvey 2 (Mo. Bot. Gard. Herb.) ;
muddy river bottom, Dover, 27 August, 1894, Fernald (Gray
Herb.) ; gravelly margin of river, Dover, 3 September, 1894,
Fernald (Gray Herb.); submerged margin of Pleasant
River, Brownville, 3 August, 1904, Parlin 1753 (Gray Herb.).

Somerset Co.: Lake George, Skowhegan, 30 June and 2 July,
1903, Haton (Mo. Bot. Gard. Herb.) ; Dead River, 15 August,
1896, Eaton (Mo. Bot. Gard. Herb.); quiet pool in river,
Dead River, 15 August, 1896, Fernald (Gray Herb.).

Waldo Co.: deadwaters of the stream, Frankfort, 21 July, 1916,
Fernald & Long 12338 (Gray Herb. and Mo. Bot. Gard.
Herb.).

Knox Co.: Chickawaukie Pond, Rockland, Fernald 1214 (Gray
Herb. ).

Lincoln Co.: muddy shore, Pemaquid River, in about 6 in. water,
Bremen, 27 August, 1899, Chamberlain (Gray Herb.).
Kennebec Co.: cold spring-pool in margin of brook, Sydney, 18
August, 1916, Fernald & Long 12339 (Gray Herb.); river
margin, in mud, Waterville, 2 September, 1898, Fernald
2824 (Gray Herb.); Cobbossee Contee Lake, Winthrop,
August, 1898, Battey (Gray Herb.); Winthrop, 28 August,

1898, Battey (Gray Herb.).

Sagadahoc Co.: tidal mud flats of the river, Bowdoinham, 14-19
September, 1916, Fernald & Long 12342 (Gray Herb. and
Mo. Bot. Gard. Herb.); border of salt marsh, Back River
Creek, Woolwich, 15 September, 1916, Fernald & Long
12343 (Gray Herb.).

Franklin Co.: Bay Pond north of Bullhorse Pond, south end
Great Pond, Industry, 14 August, 1894, Fernald (Mo. Bot.
Gard. Herb. and Gray Herb.); cold spring entering North-

[Vol. 9
162 ANNALS OF THE MISSOURI BOTANICAL GARDEN

west Pond, n. Franklin Co., 14 July, 1895, Coville 84 (U.S.
Nat. Herb. and N. Y. Bot. Gard. Herb.); Wilson Stream,
East Wilton, 11 August, 1894, Fernald (Gray Herb.).

Androscoggin Co.: river at Mechanics Falls, 28 August, 1897,
Allen (Mo. Bot. Gard. Herb. and Gray Herb.) ; Lake Auburn,
Auburn, 15 September, 1904, Winslow (Mo. Bot. Gard.
Herb.); South Poland, 1893 and 1895, Furbish (Gray
Herb.); Livermore Falls, Furbish (Gray Herb.).

Cumberland Co.: muddy bank, Androscoggin River, Brunswick,
1 August, 1894, Davis (U.S. Nat. Herb.) ; sandy bottom of
Sand Pond, Baldwin, 30 August, 1916, Fernald, Long &
Norton 12337 (Gray Herb. and Mo. Bot. Gard. Herb.).

Oxford Co.: shallow water of brook, Buckfield, 8 August, 1894,
Allen (Gray Herb.).

York Co.: in Newichawammick River, N. Berwick, 25 September,
1897, Parlin & Fernald 922 (Gray Herb.); rocky bed of
Great Works River, No. Berwick, 25 September, 1897,
Fernald (in part) (Gray Herb.).

New Hampshire: wiers on Lake Winnipiseogee, 19 September,
1856, Engelmann (Mo. Bot. Gard. Herb. and Gray Herb.),
TYPE; at mouth of “Sucker Brook” and in Lake Sunapee,
17 July, 1903, Waters (Mo. Bot. Gard. Herb.) ; Newmarket,
19 August, 1899, Eaton (Mo. Bot. Gard. Herb. and Univ.
Minn. Herb.); Country Pond, Newton, 18 August, 1896,
Eaton 441 (Mo. Bot. Gard. Herb. and U. S. Nat. Herb.) ;
Alton Bay, 1894, Eaton (Mo. Bot. Gard. Herb.); Noyes
Pond, Seabrook, 13 August, 1899, Eaton ser. 2, 187 (Mo.
Bot. Gard. Herb. and Univ. Minn. Herb.) ; pond on Lamprey
River, Epping, August, 1896, Haton (Mo. Bot. Gard. Herb.) ;
wiers on Lake Winnipiseogee, 23 September, 1863, Mann
(Mo. Bot. Gard. Herb., U. S. Nat. Herb., and Gray Herb.) ;
Lake Winnipiseogee, 28 September, 1866, Boott (Mo. Bot.
Gard. Herb. and Gray Herb.); Echo Lake, Franconia, 12
September, 1862, Boott (Mo. Bot. Gard. Herb. and Gray
Herb.); Echo Lake, Franconia, 31 July, 1863, Boott (Mo.
Bot. Gard. Herb. and Gray Herb.); Eagle Lake, Mt. Laf-
ayette, alt. 4200 ft., 26 September, 1891, FE. & C. E. Faxon
(Gray Herb.); country pond, East Kingston, August,
1895, Eaton (Mo. Bot. Gard. Herb.); late form, out
of water, East Kingston, 18 September, 1895, Dodge

1922]

PFEIFFER—MONOGRAPH OF THE ISOETACEAE 163

(Gray Herb.); borders of pond, East Kingston, 6 Oc-
tober, 1895, Eaton 699 (Mo. Bot. Gard. Herb. and Univ.
Minn. Herb.) ; “Dismal Pool” near mouth of Saco River,
White Mt., 26 August, 1882, £. & C. E. Faxon 10 (Mo. Bot.
Gard. Herb. and Gray Herb.); Saco Lake, Crawfords, 17
July, 1898, H. & C. #. Faxon 4 (Gray Herb.) ; Ammonoosue
Lake, Crawfords, 17 July, 1893, ZH. & C. E. Fazon 3 (Gray
Herb. and N. Y. Bot. Gard. Herb.); submerged flats at
Kingston, August, 1896, Eaton (Mo. Bot. Gard. Herb.);

early form growing sabmersed, East Flats, East Kingston,
28 July, 1896, Dodge (Gray Herb.): Flats, East Kingston, 28
July, 1896, Haton (Mo. Bot. Gard. Herb.) ; Epping, Zaton
431 (Mo. Bot. Gard. Herb.) ; Epping, 12 August, 1896, Eaton
425a (Mo. Bot. Gard. Herb.); West Epping, Eaton 482b
(Mo. Bot. Gard. Herb.) ; Pautuckaway Pond, Nottingham,
29 July, 1826, Haton 483a (Mo. Bot. Gard. Herb.); East
Kingston, 28 Tuly, 1896, Haton 364 (Mo. Bot. Gard. Herb.
and U. 8. Nat. Herb.) ; sandy bottoms of ponds, East King-
ston, August, 1895, Haton (N. Y. Bot. Gard. Herb.); East
eae 6 July, 1896, Eaton 239 (Mo. Bot. Gard. Herb.) ;

Trickling Falls, Kast eae or 29 July, 1896, Haton (Mo.
Bot. Gard. esa Rod Miller’s, Seabrock, Baron (Mo. Bot.
Gard. Herb.) ; Conway Lake, 25 August; 1904, Davenport
(Mo. Bot. Gard. Herb.) ; Lake W innipisaukee, 10 September,
1910, Sargent 27 (Gray Herb.); Gustin Pond, Marlow, 29
J ae 1899, Fernald 186 (in part) (Gray Herb.) ; clayey aay
shores of Thorndike Pond, 29 September, 1897, Rand &
Robinson 927 (Gray Herb.) : Seabrook, September. 1895,
Eaton (U. 8. Nat. Herb. and Univ. Minn. Herb.) ; Gilman-
ton, 4 September, 1911, Lunt 60 (Gray Herb. -) 5 shingly mar-
gin of Fish Pond, Columba, Coos Co., 22 August, 1912,

Pease 13790 ce Herb.) ; Soeeene bogs, by small ponds
near timber line, western slope of Mt. Lafayette, Franconia,
17-18 July, 1915, Fernald & Smiley 11496 (Gray Herb.) ;

Loutenstein, heoiar Lake, 13 August, 1914, wade
(Gray Heh. Je

Vermont: Lake Dunmore, 1859, Chapman (Mo. Bot. Gard.

Herb.); in small pond near summit of Mt. Mansfield,
August, 1863, Mann (Gray Herb.); Lake of the Clouds,
Mt. Mansfield, 10 August, 1876, Pringle (Mo. Bot. Gard.

[Vol. 9
164 ANNALS OF THE MISSOURI BOTANICAL GARDEN

Herb.) ; pond on Sterling Mt., 20 August, 1877, C. H. Faxon 1
(Mo. Bot. Gard. Herb.); Notch Pond, Ferdinand, Essex
Co., Eggleston 1785 (Mo. Bot. Gard. Herb., Gray Herb., and
N. Y. Bot. Gard. Herb.) ; Pike Pond, Stratton, August 6-10,
1900, Eggleston 2201 (Mo. Bot. Gard. Herb., N. Y. Bot.
Gard. Herb., and Gray Herb.) ; shallow water, Peacham, 14
August, 1884, Blanchard (N. Y. Bot. Gard. Herb. and Dudley
Herb.) ; Foster’s Pond, Peacham, September, 1881, Blanch-
ard (Mo. Bot. Gard. Herb.); Stratton Plateau, Stratton,
6-10 August, 1900, Eggleston 2201 (Dudley Herb.); Lake
of the Clouds, Mt. Mansfield, 14 August, 1901, Eggleston
2472 (U.S. Nat. Herb., Gray Herb., Mo. Bot. Gard. Herb.
and Dudley Herb.); shallow muddy shores, Lake of the
Clouds, Mt. Mansfield, 31 July, 1893, Eggleston 699 (Mo.
Bot. Gard. Herb. and Univ. Minn. Herb.); Lake of the
Clouds, Mt. Mansfield, 8 August, 1877, Faxon 2 (Mo. Bot.
Gard. Herb.) ; same place and date, without number, Faxon
(Gray Herb.); small pond, Lake of the Clouds, Mt. Mans-
field, August, 1868, Mann (Mo. Bot. Gard. Herb. and Gray
Herb.) ; Lake of the Clouds, 31 July, 1893, Hinsdale & Eg-
gleston (Dudley Herb. and U.S. Nat. Herb.) ; Larger Lake of
the Clouds, 15 July and 31 July, 1898, Miller 1 & 2 (Gray
Herb.); Pleiad Lake, alt. 2500 ft., Hancock, 18 September,
1896, Brainerd (Gray Herb.) ; Chittenden, 18 August, 1895,
Eggleston (Univ. Minn. Herb.); Joe’s Pond, W. Danville,
5 July, 1894, Burbank, Grout & Eggleston (U. 8. Nat. Herb.
and N. Y. Bot. Gard. Herb.) ; muddy shores of Pike’s Mill
Pond, Stratton, 10 August, 1894, Grout (N. Y. Bot. Gard.
Herb.); Lake Champlain, north end of Isle La Motte, 2
September, 1879, Pringle (Mo. Bot. Gard. Herb., N. Y. Bot.
Gard. Herb., and U. 8. Nat. Herb.) ; North Pond, Stratton,
30 July, 1894, Grout (N. Y. Bot. Gard. Herb.) ; Lake Cham-
plain, n. end of Isle La Motte, 19 July, 1878, Pringle (Mo.
Bot. Gard. Herb.); muddy banks, Lower Haystack Pond,
Wilmington, Windham Co., 6 October, 1912, St. John 630
(Gray Herb.) ; Kelsey’s Beach, in water 1-2 ft. deep, Lake
Dunmore, Salisbury, 23 August, 1908, Dutton) 397 (Gray
Herb.) ; Stony Pond, region of Pine Hill, Rutland, 25 July,
1909, Dutton 198 (Gray Herb.) ; region Battell’s Pond, alt.
about 2500 ft., Hancock, 22 August, 1909, Dutton 260 (Gray

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 165

Herb.) ; Connecticut River, Norwich, September, 1876, Jesup
(N. Y. Bot. Gard. Herb.).

Massachusetts:

Essex Co.: Attitash, 27 June, 1896, Eaton 197 (Mo. Bot. Gard.
Herb.); muddy banks of Merrimac River, Newburyport,
1895, Haton (Dudley Herb.) ; Attitash, 31 July, 1896, Eaton
880 (Mo. Bot. Gard. Herb.) ; Kimballs Pond, Amesbury, 15
August, 1899, Haton 192 (Mo. Bot. Gard. Herb.) ; Kimballs
Pond, Amesbury, 138 August, 1899, Haton (Mo. Bot. Gard.
Herb. and Univ. Minn. Herb.); Kimballs Pond, Amesbury,
13 August, 1896, Haton (Mo. Bot. Gard. Herb.) ; Tuxbury’s
Pond, Amesbury, 19 September, 1897, Haton 919 (Mo. Bot.
Gard. Herb.) ; Marshall’s Pond, Amesbury, 18 August, 1908,
Eaton (Mo. Bot. Gard. Herb.); Crane Pond, Bagfield, 6
July, 1893, Lunt (Gray Herb.); Bates Pond, Wenham, 29
July, 1896, Haton 377 (Mo. Bot. Gard. Herb.); Pleasant
Pond, Wenham, C. EF. Faxon 6 (Mo. Bot. Gard. Herb.) ;
Pleasant Pond, Wenham, without date or number, C. £.
Faxon (Gray Herb.); Beaver Pond, Beverly, August, 1870,
Russell (Mo. Bot. Gard. Herb.); bank of Merrimac, New-
buryport, 12 September, 1895, Eaton (Mo. Bot. Gard. Herb.
and Univ. Minn. Herb.); bank of Merrimac, Newburyport,
August, 1895, Haton (N. Y. Bot. Gard. Herb.); Chatt-
wick’s Pond, W. Boxford, 1 September, 1882, Robinson (Mo.
Bot. Gard. Herb.) ; banks of Merrimac R., Newburyport, 12
September, 1897, Haton (Univ. Minn. Herb.) ; Manchester
and vicinity, without date, Chamberlain (N. Y. Bot. Gard.
Herb.); muddy pool, Amesbury, 18 August, 1899, Haton
(Univ. Minn. Herb.) ; Ipswich River, Ipswich, 29 July, 1874
and 1875, Morong (N. Y. Bot. Gard. Herb.) ; Ipswich River,
Ipswich, July, 1875, Morong (U.S. Nat. Herb.); East An-
dover, 1903, Holt (Gray Herb.); Wenham, Collins (Gray
Herb.); pond on Skug River, above Sawmill Road, 22
September, 1903, Pease 2775 (Gray Herb.).

Middlesex Co.: Woburn, 16 November, 1862, without collector’s
name (Mo. Bot. Gard. Herb.) ; Woburn, 3 September, 1866,
Boott (Gray Herb.); Small Round Pond, Woburn, 8 Sep-
tember, 1867, Boott (Mo. Bot. Gard. Herb.) ; Small Round
Pond, Woburn, 23 September, 1867, Boott (Mo. Bot. Gard.
Herb.) ; Small Round Pond, Woburn, 5 August, 1860, Boott

166

[Vol. 9
ANNALS OF THE MISSOURI BOTANICAL GARDEN

(Mo. Bot. Gard. Herb. and Gray Herb.) ; Small Round Pond,
Woburn, 29 September, 1867, Boott (Mo. Bot. Gard. Herb.) ;
Small Round Pond, Woburn, 11 August, 1867, Boott (Mo.
Bot. Gard. Herb. and Gray Herb.); Small Round Pond,
Woburn, 20 October, 1857, Boott (Mo. Bot. Gard. Herb.) ;
Small Round Pond, Woburn, 9 June, 1867, Boott (Mo. Bot.
Gard. Herb.); Small Round Pond, Woburn, 2 September,
1866, Boott (Mo. Bot. Gard. Herb. and Gray Herb.) ; Small
Round Pond, Woburn, 18 September, 1866, Boott (Mo. Bot.
Gard. Herb., Gray Herb., and N. Y. Bot. Gard. Herb.) ;
Smail Round Pond, Woburn, 14 July, 1867, Boott (Mo.
Bot. Gard. Herb.); Small Round Pond, Woburn, 15 & 22
August, 1869, Boott (Gray Herb.); Mystic Pond, without
date, C. E. Faxon (Gray Herb.); Mystic Pond, 6 August,
1865, Boott (Mo. Bot. Gard. Herb. and Gray Herb.);
Mystic Pond, 30 July, 1865, Boott (Gray Herb.);
Mystic Pond, 2 September, 1866, Boott (Mo. Bot.
Gard. Herb.); Mystic Pond, 3 September, 1866, Boott
(Gray Herb.); Mystic Pond, 14 June, 1867, Boott
(Mo. Bot. Gard. Herb.); Mystic Pond, Medford,
without date, Boott (Gray Herb.); pond in Woburn,
without date, Davenport (Gray Herb.); Mystic Pond,
29 August, 1869, Boott (N. Y. Bot. Gard. Herb.) ; Sherman’s
Pond, Waltham, 31 August, 1869, Boott (N. Y. Bot. Gard
Herb.) ; Spot Pond, Stoneham, 19 August, 1899, Rich (Gray
Herb.) ; Spot Pond, Stoneham, without date, Collins (Gray
Herb.); Skug River, North Reading, 14 September, 1903,
Pease 2670 (Gray Herb.); submerged in running water,
Ashland, 17 July, 1879, Morong (N. Y. Bot. Gard. Herb.):
Nutting Pond, Billerica, 11 August, 1869, Boott (N. Y. Bot.
Gard. Herb.) ; sandy margin of Heard’s Pond, Wayland, 10
September, 1909, Fernald (Gray Herb.) ; Mystic Pond, near
Bacon’s, 10 September, 1876, Boott (N. Y. Bot. Gard.
Herb.); Mystic Pond at Grover, 29 August, 1869, Boott
(N. Y. Bot. Gard. Herb.); Mystic Pond, 29 August, 1882,
Perkins (Gray Herb.); Mystic Pond, 4 July, 1867, Boott
(Mo. Bot. Gard. Herb. and Gray Herb.); Mystic Pond, 1
September, 1867, Boott (Mo. Bot. Gard; Herb. and Gray
Herb.); brook above gas works, Arlington, 1 September,
1867, Boott (Gray Herb.); Mystic Pond, mouth of Arling-
ton Brook, 30 July, 1864, Boott, (Mo. Bot. Gard. Herb. and

1922)

PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 167

N. Y. Bot. Gard. Herb.); Mystic Pond, mouth of Arling-
ton Brook, 2 June, 1867, Boott (Mo. Bot. Gard. Herb.) ;
along banks of Mystic Pond, 21 October, 1866, Boott (Mo.
Bot. Gard. Herb.) ; Mystic Pond, 14 and 30 July, 1864, Boott
(Gray Herb.) ; east side of Mystic Pond, 8 September, 1867.
Boott (Mo. Bot. Gard. Herb.); west side of Mystic Pond,
north of Brook, 12 July, 1868, Boott (Gray Herb.) ; south
side of Spy Pond, Arlington, 5 and 9 September, 1867, Boott
(Mo. Bot. Gard. Herb.); Spot Pond, 6 September, 1868,
Boott (N. Y. Bot. Gard. Herb.) ; Spot Pond, Stoneham, 23
July, 1867, Boott (Mo. Bot. Gard. Herb.); Spot Pond, 18
November, 1866, Boott (U.S. Nat. Herb.) ; Horn Pond, Wo-
burn, September, 1862, Mann (Gray Herb.) ; island in middle
of Horn Pond, 11 July, 1867, Boott (Mo. Bot. Gard.
Herb. and Gray Herb.) ; northwest side Horn Pond, 16 Sep-
tember, 1869, Boott (N. Y. Bot. Gard. Herb.); Fresh Pond,
17 September, 1867, Boott (Mo. Bot. Gard. Herb. and Gray
Herb.) ; Concord Brook, 20 August, 1866, Boott (Mo. Bot.
Gard. Herb.); Round Pond, Woburn, 1 October, 1874,
Davenport (N. Y. Bot. Gard. Herb.); Hammond’s Pond,
Brookline, without date, C. E. Faxon (Mo. Bot. Gard.
Herb.) ; Round Pond, Woburn, without date, C. HE. Faxon
(Mo. Bot. Gard. Herb.); Hammond’s Pond, 1878, Farlow
(Mo. Bot. Gard. Herb.) ; Tofit Swamp Brook, Lexington, 17
July, 1867, Boott (Gray Herb. and N. Y. Bot. Gard. Herb.) ;
brook in Tofit Swamp, Lexington, 9 September, 1867, Boott
(Mo. Bot. Gard. Herb. and Gray Herb.); South Natick, 14
July, 1879, Morong (Mo. Bot. Gard. Herb.) ; “entirely sub-
merged in pool, South Natick”, 18 August, 1883, Morong
(N. Y. Bot. Gard. Herb.); ponds, West Cambridge; 1861,
Boott (Mo. Bot. Gard. Herb.); Concord, in streams, Sep-
tember, 1863, Mann (Gray Herb.); Concord, 1 October,
1863, Mann (Mo. Bot. Gard. Herb.) ; Concord, without date,
Mann (Gray Herb.); small pond in Winchester (for-
merly Woburn), August, 1876, Morong 353 (U. S. Nat.
Herb.) ; small pond in Winchester, 22 August, 1876, Morong
(N. Y. Bot. Gard. Herb.) ; brooks, slow moving water, Mel-
rose, 8 July, 1875, Morong (N. Y. Bot. Gard. Herb.); in
running water, Melrose, September, 1876, Morong (U. S.
Nat. Herb.); Sandbury River, Framingham, September,

[Vol. 9
168 ANNALS OF THE MISSOURI BOTANICAL GARDEN

1894, Smith (Mo. Bot. Gard. Herb.); from a canal in So.
Natick, water about 1 ft. deep, 25 June, 1879, Morong (N.
Y. Bot. Gard. Herb. and Mo. Bot. Gard. Herb.); entirely
submerged, Charles R., So. Natick, 4 August, 1879, Morong
(N. Y. Bot. Gard. Herb.).

Norfolk Co.: Neponset River, Readville, 28 July, 1870,
Boott (N. Y. Bot. Gard. Herb.); Highland Lake, Norfolk,
1 August, 1909, Ware 724 (Mo. Bot. Gard. Herb.) ; Ham-
mond’s Pond, Brookline, C. EH. & W. Faxon 8 (Gray Herb.) ;
Lake Massapoag, 17 October, 1897, Greenman 2314 (Mo.
Bot. Gard. Herb.) ; Dedham, growing in shallow water, mud
bottom, 24 July, 1902, Forbes (Gray Herb.); Lake Massa-
poag, 11 September, 1903, Haton (Mo. Bot. Gard. Herb.) ;
in Sutton’s Brook, at its junction with Charles River, Need-
ham, 12 July, 1885, Fuller (Gray Herb.).

Bristol Co.: Mulberry Brook, Easton, 16 August, 1903, Haton
(Mo. Bot. Gard. Herb.); Flyaway Pond, No. Easton, 15
July, 1908, Haton (Mo. Bot. Gard. Herb.) ; Canoe River, 2
August, 1903, Eaton (Mo. Bot. Gard. Herb.); Watson’s
Pond, Taunton, 12 July, 1903, Eaton (Mo. Bot. Gard.
Herb.) ; few stations in stream, Swansea, 16 August, 1912,
Sanford 38 (Gray Herb.).

Worcester Co.: Massapoag Lake, 11 September, 1903, Haton
(Mo. Bot. Gard. Herb.); Uxbridge, 30 August, 1864, Rob-
bins (Mo. Bot. Gard. Herb. and Gray Herb.) ; “river,” Ux-
bridge, 1 August, 1867, Robbins (N. Y. Bot. Gard. Herb.) ;
pond, Grafton, 27 July, 1866, Robbins (Mo. Bot. Gard. Herb.
and N. Y. Bot. Gard. Herb.); pond connected with Black-
stone River, 30 August, 1864, Robbins (Mo. Bot. Gard.
Herb.) ; Uxbridge, 1845, Robbins (Mo. Bot. Gard. Herb.) ;
Uxbridge, without date, ex. herb. Robbins (N. Y. Bot. Gard.
Herb.); millpond, depth of 2-3 ft., Uxbridge, 30 August,
1866, Robbins (Mo. Bot. Gard. Herb.); Cohasset Brook,
Southbridge, alt. 640 ft., 12 August, 1899, Harper (N. Y.
Bot. Gard. Herb.) ; rocky bottom of Quenebang River, Stur-
bridge, alt. 540 ft., 23 July, 1899, Harper (Gray Herb.) ; Ux-
bridge, 31 August, 1907, Haton (Mo. Bot. Gard. Herb.).

Franklin Co.: Ashfield Pond, Ashfield, 18 July, 1909, Williams
(Gray Herb.).

Berkshire Co.: Lake Undine, Mt. Everett, 1 October, 1897, NV.

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 169

L. Britton (N. Y. Bot. Gard. Herb.) ; same station and date,
E. G. Britton (N. Y. Bot. Gard. Herb.); Spectacle Pond,
Sandisfield, 29 June, 1912, Hoffman (Gray Herb.) ; Lake Un-
dine, The Dome, Sheffield, 27 August, 1902, Hoffman (Gray
Herb.).

Massachusetts, but not located on map: “Country Pond,” 18
August, 1896, Haton 441 (Mo. Bot. Gard. Herb.) ; “Kenoza
Lake,’ 12 September, 1897, Zaton 913 (Mo. Bot. Gard.
Herb.); Pinkapog Pond, 27 August, 1869, Boott (N. Y.
Bot. Gard. Herb.).

Connecticut: Greystone, 30 August, 1907, Haton (Mo. Bot. Gard.
Herb.) ; upper end Selden’s Creek, 5 August, 1905, Graves
142 (Mo. Bot. Gard. Herb.); Mashapang Pond, Union,
20-25 August, 1902, Bissell (Mo. Bot. Gard. Herb.) ; Lyme,
13 August, 1900, Graves (Mo. Bot. Gard. Herb.) ; Selden’s
Cove, Lyme, 29 August, 1901, Bissell (Gray Herb.) ;
Selden’s Cove, Lyme, 29 August, 1901, Graves (Mo. Bot.
Gard. Herb.); submerged on sandy bottom, Selden’s Cove,
Lyme, 11 September, 1902, Graves 1 (Gray Herb.) ; W. Gosh-
en, July, 1891, Underwood (Mo. Bot. Gard. Herb. and Gray
Herb.) ; Great Brook near Poquonnock, “Lake Marshapog,
Litchfield,’ 1882, Underwood (Mo. Bot. Gard. Herb.) ; shal-
low water of pond at Graystone, Plymouth, 6 September,
1903, Bissell (in part) (Gray Herb.) ; Graystone, 30 August,
1907, Eaton (Mo. Bot. Gard. Herb.).

New York: Niagara River, below Buffalo, & September, 1866,
Clinton (Mo. Bot. Gard. Herb. and Gray Herb.) ; Niagara
River, September, 1866, Clinton (Gray Herb. and N. Y. Bot.
Gard. Herb.) ; Oneida Lake, Gilbert (Mo. Bot. Gard. Herb.) ;
Niagara River, below Buffalo, 1865, Clinton (N. Y. Bot.
Gard. Herb.); at outlet of Lake Luzerne, Warren Co., 24
August, 1867, Clinton (Mo. Bot. Gard. Herb.) ; lake on Cats-
kill Mts., July, 1868, Canby (Mo. Bot. Gard. Herb.) ; lakelet,
Catskill Mts., 19 September, 1866, Clinton (Mo. Bot. Gard.
Herb. and Gray Herb.) ; west of Lake George, shallow pool,
20 July, 1862, Les Lesquereux (Mo. Bot. Gard. Herb.) ; Niag-
ara River, 2 September, 1862, Clinton (Mo. Bot. Gard.
Herb.) ; submerged banks, Oneida Lake, 20 July, 1879, Paine
(Mo. Bot. Gard. Herb.) ; Greenwood Lake, Orange Co., 15

[Vol. 9
170 ANNALS OF THE MISSOURI BOTANICAL GARDEN

July, 1876, Schrenk (Mo. Bot. Gard. Herb.) ; Southern Pond,
Catskill Mts., 1866, Clinton (Gray Herb.); Catskill Lake,
June, 1888, Canby (Mo. Bot. Gard. Herb.) ; submerged on
east shore of Cayuta Lake, Schuyler Co., 28 August, 1893,
Clinton (U. 8. Nat. Herb.); Lake Tear of the Clouds, Mt.
Marcy, 6 September, Britton (N. Y. Bot. Gard. Herb.) ; Lake
Mahopac, 4 October, 1891, Morong (N. Y. Bot. Gard.
Herb.); Upper Ansable Pond, Adirondacks, 3 September,
1894, Britton (N. Y. Bot. Gard. Herb.); on sand bottom,
Lake Placid, 6 September, 1896, Dr. & Mrs. Britton (N. Y.
Bot. Gard. Herb.) ; Clear Lake, south of Elk Lake, Adiron-
dacks, 4 September, 1894, Britton (N. Y. Bot. Gard. Herb.) ;
Chilson Lake, 31 August, 1900, Dr. & Mrs. Britton (N. Y.
Bot. Gard. Herb.) ; Cinnamon Lake, Steuben Co., 31 August,
1898, Barber 394 (Mo. Bot. Gard. Herb.); submerged on
sandy bottom, Duck Lake, Conquest, Cayuga Co., 1 July,
1916, Eames, Metcalf & Wiegand 5445 (Gray Herb.).

New Jersey: submerged on sandy bottom, Budd’s Lake, Morris
Co., 2 September, 1904, Mackenzie 1025 (Mo. Bot. Gard.
Herb.); shores of Tom’s River, Ocean Co., 18 September,
1873, Parker (Gray Herb.) ; submerged in salt water, Tom’s
River, Ocean Co., 18 September, 1873, 17 artindale (Mo. Bot.
Gard. Herb.) ; bed of Tom’s River, Ocean Co., 16 September,
1867, Parker (Mo. Bot. Gard. Herb. and Gray Herb.) ; sub-
merged, Tom’s River, Ocean Co., 17 September, 1867, Smith
(Mo. Bot. Gard. Herb.) ; growing abundantly on submerged
sand bars, in Tom’s River, 15 September, 1867, Smith (Gray
Herb.); Lake Hopotong, Morris Co., 25 September, 1869,
Porter 1953 (Mo. Bot. Gard. Herb.); Ridgewood, 21 July,
1880, Brown (Mo. Bot. Gard. Herb.).

Pennsylvania: Great Pond, Pocono Mt., Carbon Co., 7 August,
1867, Canby (Mo. Bot. Gard. Herb.) ; Great Lake, Carbon
Co., 7 August, 1867, Porter (Mo. Bot. Gard. Herb.) ; Mont-
rose, Susquehanna Co., 24 May, 1869, Garber (Mo. Bot.
Gard. Herb.); Presque Isle, Erie, September, 1868, Garber
(Mo. Bot. Gard. Herb.); Erie, July, 1868, Garber (Gray
Herb.) ; Presque Isle, Erie, 28 July, 1868, Garber (Mo. Bot.
Gard. Herb. and N. Y. Bot. Gard. Herb.); Delaware R. at
Monroe, Bucks Co., 24 July, 1886, Ruth (Univ. Minn.
Herb.) ; Bowman’s Pond, Wyoming, 17 July, 1897, Brown

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE cris

(U. S. Nat. Herb.) ; Poyntelle Pond, Wayne Co., 20 and 21
July, 1900, Clute (Mo. Bot. Gard. Herb.) ; Coxtown Pond,
Wayne Co., 20 July, 1900, Clute (Mo. Bot. Gard. Herb.).

Ontario: Partridge Lake, 50 mi. northeast of Bellesville, Hast-
ings, 21 August, 1863, John Macoun (Mo. Bot. Gard. Herb.) ;
Hastings, 12 July, 1870, John Macoun (Mo. Bot. Gard.
Herb.) ; head of ship canal, Sault Ste. Marie, 7 August, 1869,
John Macoun (Mo. Bot. Gard. Herb.); in Lake Superior,
shores of Michipicoten Isl., at Grierson’s Landing, 24 July,
1869, John Macoun (Mo. Bot. Gard. Herb.) ; water, Nipigon
River, 21 July, 1884, John Macoun (Gray Herb. and N. Y.
Bot. Gard. Herb.); on gravel bottom, Orient Bay, Lake
Nipigon, midway of east shore of bay, in 2 ft. water, 23 July,
1911, O. H. & G. K. Jennings 6582 (Gray Herb. and U. 8.
Nat. Herb.); marshes, Lake Nipigon, 10 July, 1884, John
Macoun (Gray Herb.); Nipigon River, 23 July, 1884, John
Macoun 14222 (Gray Herb. and N. Y. Bot. Gard. Herb.) ;
mouth of Nipigon River, Lake Superior, 23 June, 1884, John
Macoun (N. Y. Bot. Gard. Herb.); Catfish Lake, Algon-
quin Park, 23 July, 1900, John Macoun 24942 (N. Y. Bot.
Gard. Herb.); Opeonga Lake, Algonquin Park, 16 August,
1900, John Macoun 24940 (N. Y. Bot. Gard. Herb.).

Michigan: Belle Isle, Detroit River, 6 August, 1871, Gillman
(Mo. Bot. Gard. Herb.) ; Gogebic Co., summer, 1919, Dar-
lington (Mo. Bot. Gard. Herb.).

Ohio: submerged in 10-20” water, Brady’s Lake, Portagé Co.,
15-30 June, 1913, Hopkins (U. 8S. Nat. Herb., N. Y. Bot.
Gard. Herb., and Gray Herb.).

Wisconsin: Plum Lake, Sayner, Vilas Co., summer 1918, Good-
speed (Mo. Bot. Gard. Herb.) ; muddy shore, Three Lakes.
Oneida Co., 13 August, 1918, Hoffman (Mo. Bot. Gard.
Herb.) ; rocky bottom, Crooked Lake, Three Lakes, Oneida
Co., 26 August, 1918, Hoffman (Mo. Bot. Gard. Herb.).

Minnesota: Mountain Lake, Cook Co., 21 August, 1901, Mac-
Millan, Brand & Lyon 177 (Mo. Bot. Gard. Herb. and Univ.
Minn. Herb.); small lake on Gunflint trail near 13 mile
post, Cook Co., 14 August, 1901, MacMillan, Brand & Lyon
71 (Mo. Bot. Gard. Herb. and Univ. Minn. Herb.); Mud
Lake, Cook Co., 20 August, 1901, MacMillan, Brand & Lyon
70 (Mo. Bot. Gard. Herb.); Echo Lake, Mahtomedi, 14

[Vol. 9
172 ANNALS OF THE MISSOURI BOTANICAL GARDEN

August, 1902, Wheeler 1227 (Univ. Minn. Herb.); Echo
Lake, 16 August, 1904, Lyon 874, 875, & 876 (Univ. Minn.
Herb.) ; South Lake, Cook Co., 19 August, 1901, MacMillan,
Brand & Lyon 146 (Univ. Minn. Herb.); Mud Lake, Cook
Co., 22 August, 1901, MacMillan, Brand & Lyon 198 (Univ.
Minn. Herb.) ; Kove Lake, Cook Co., 20 August, 1901, Mac-
Millan, Brand & Lyon 171 (Univ. Minn. Herb.); Mud
Lake, Cook Co., 20 August, 1901, MocMillan, Brand & Lyon
170 (Univ. Minn. Herb.); Long Lake, Vermilion Lake, Lat.
48°, 25 July, 1886, Arthur, Bailey & Holway B413 (Univ.
Minn. Herb. and Gray Herb.); Vermilion Lake, 18 July,
1886, Arthur, Bailey & Holway B 87 (Univ. Minn. Herb.
and Gray Herb.).

Idaho: Bitter Root Forest Reserve, alt. 1800 m., 1 September,
1897, Leiberg 71 (Mo. Bot. Gard. Herb.) ; Bitter Root For-
est Reserve, Head of Bear Creek, alt. 2250 m., 1 September,
1897, Leiberg 2971 (U.S. Nat. Herb.).

Colorado: Seven Lakes, 3500 m., 1 September, 1902, R. EH. &
E. 8. Clements 493,1 (Mo. Bot. Gard. Herb., U. S. Nat.
Herb., and Gray Herb.).

Utah: lake near head of Bear River, Uintah Mts., 4 August,
1869, Watson 1371 (Mo. Bot. Gard. Herb., U. S. Nat. Herb.,
and N. Y. Bot. Gard. Herb.).

Vancouver Island: Prospect Lake near Victoria, 25 July, 1908,
John Macoun 86379 (Gray Herb. and N. Y. Bot. Gard.
Herb.) ; Alberni, 10 August, 1887, John Macoun 14217 (Gray
Herb.) ; Sproat Lake, 12 August, 1887, John Macoun 14218
Gray Herb.); Sooke, 2 August, 1893, John Macoun
14215 (Gray Herb.); Sooke, 2 August, 1893, John Macoun
6382 (Mo. Bot. Gard. Herb.); salt marsh, Somas River,
2 August, 1887, John Macoun 14216 (Gray Herb.); in
mud, Somas River, Alberni, with Limosella and Lilaea, 20
June, 1916, Henry 9082 (Gray Herb.).

Washington: shallow ponds, alt. 6000 ft., Chiquash Mts., Skai-
mania Co., 16 August, 1900, Suksdorf 2210 (Mo. Bot. Gard.
Herb.); in lake, alt. 5000 ft., Mt. Rainier, August, 1895,
Piper 2131 (Mo. Bot. Gard. Herb., N. Y. Bot. Gard. Herb.,
and Gray Herb.); (lake 2 ft. deep voleanic ash) Mirror
Lake, Mt. Rainier, 23 August, 1901, Flett 1929x (Mo. Bot.
Gard. Herb., N. Y. Bot. Gard. Herb., and U. 8. Nat. Herb.) ;

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 173

Reflection Lake, Mt. Rainier, 20 July, 1907, Cowles 776 (Mo.
Bot. Gard. Herb.); Lake Chelan, 22 September, 1897, Gor-
man 716 (Gray Herb.); in Bitter Lake, near Seattle, July,
1891, Piper 1117 (N. Y. Bot. Gard. Herb.).

California: at alt. 8000 ft., Mountain Lakes, head of Trinity
River, 1 September, 1882, Pringle (Mo. Bot. Gard. Herb., U.
S. Nat. Herb., and Gray Herb.) ; Castle Lake (near Scott’s
Mountain), mountains about headwaters of Sacramento
River, scattered in gravelly bottom in 2-6 ft. water, 14
August, 1881, Pringle (Mo. Bot. Gard. Herb. and Gray
Herb.).

42a. Forma robusta Pfeiffer, comb. nov.
I. echinospora var. robusta Engelm. Trans. St. Louis Acad.

Sci. 4: 380. 1882.

I. echinospora Braunii f. robusta Clute, Fern Allies, 221, 258.

1905.

I. Gravesii Eaton, Fernwort Papers, 14. 1900.

I. valida var. Gravesii Clute, Fern Allies, 348. 1905.

Stouter than the species, with leaves as numerous as 75, 12-15
em. long; stomata usually numerous, more so than in the species.

Specimens examined:

Vermont: Lake Champlain, north end of Isle La Motte, 2 Sep-
tember, 1879, Pringle (Mo. Bot. Gard. Herb. and Gray
Herb.), type; Lake Champlain, 19 July, 1878, Pringle (Mo.
Bot. Gard. Herb.).

Connecticut: Tyler’s Pond, near the outlet, W. Goshen, August,
1883, Underwood (Mo. Bot. Gard. Herb.) ; Tyler’s Pond, W.
Goshen, August, 1889, Underwood & Cook (N. Y. Bot.
Gard. Herb.) ; gravelly and sandy tidal shores, Selden’s Cove,
Lyme, 31 August, 1900, Graves (Mo. Bot. Gard. Herb. and
U.S. Nat. Herb.) ; same, Graves 145 (Mo. Bot. Gard. Herb.) ;
submerged, growing in mud, Selden’s Cove, Lyme, 29 Aug-
ust, 1901, Graves (Mo. Bot. Gard. Herb. and Gray Herb.) ;
Selden’s Cove, Lyme, 27 August, 1907, Haton (Mo. Bot.
Gard. Herb.); shallow water of pond at Graystone, Ply-
mouth, 6 September, 1908, Bissell (Mo. Bot. Gard. Herb.
and Gray Herb.) ; Bristol, 1888, Bishop (U.S. Nat. Herb.) ;

[Vol. 9
174 ANNALS OF THE MISSOURI BOTANICAL GARDEN

Stratford, plentiful locally in sandy gravel of tidal flats of
Housatonic River, 29 September, 1919, Hames 9671 (Gray
Herb.).

Plants described by Eaton as I. Gravesu have the appearance
of robust forms of J. Braunii, are similar in abundance of sto-
mata, and appear like immature specimens in spore markings.
In cases where mature spores have been found in the soil, they
prove to have the spines characteristic of J. Brauni, as well as
the size. This is true of the specimens reported above from Con-
necticut, all of which have been collected at about the same sea-
sun of the year.

There is one other possible position for this Connecticut ma-
terial, if the assumption that it is immature proves to be un-
founded. Young megaspores of the echinate group have very
much the appearance that all the spores of /. Hatoni Dodge
show. In habit, this stout form is enough like the latter to sug-
gest a possible connection in this direction. Experimental work
and collections through a longer interval of the fruiting season
should clear up this doubtful form.

42b. Var. maritima (Underw.) Pfeiffer, comb. nov.

I. maritima Underw. Bot. Gaz. 13: 94. 1888.

I. echinospora var. maritima Eaton, Fern Bull. 13: 52. 1905.

I. Macouni Eaton, Fern Bull. 8: 12. 1900.

Corm 2-lobed; leaves 7-15, 3-12 em. long, green, chiefly slen-
der, with fine-pointed tips and rather wide membranaceous bor-
der at base; stomata numerous; peripheral strands lacking; l-
gule triangular, little longer than wide; sporangia globose to
oblong, 3-4 mm. long, with velum usually narrow, sometimes
covering 14 of sporangium; megaspores white, chiefly 380-500 u,
rarely 600, in diameter, usually densely marked with stout
blunt spines, sometimes confluent into toothed ridges; micro-
spores 30-39 » long, chiefly papillose.

Distribution: Atkah and Vancouver Islands, Washington.

Specimens examined:

Aleutian Archipelago: pools in Atkah Isl., Behring Sea, 26 Aug-
ust, 1891, Macoun 14227 (Mo. Bot. Gard. Herb. and Gray
Herb.).

Vancouver Island: Alberni, Barclay Sound, August, 1887, J. Ma-
coun (Mo. Bot. Gard. Herb.); Great Central Lake, 2 July,

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 175

1907, Rosendahl 2050 (Mo. Bot. Gard. Herb., Gray Herb., U.
S. Nat. Herb., and Univ. Minn. Herb.).

Washington: lake 2 ft. deep (volcanic ash), Mirror Lake, Mt.
Rainier, 23 August, 1901, Flett 1930 (Mo. Bot. Gard. Herb.
and N. Y. Bot. Gard. Herb.).

It seems possible that this is but a form of J. Braunu Dur.
growing under rather hard conditions. The distinguishing
features are the large microspores with their papillose markings,
in contrast to the usual smooth J. Brauwnii spores of 35 yu or less;
the more numerous stomata, which are probably due to greater
exposure; and the narrow velum, a feature which is shared, how-
ever, by most western specimens of /. Braunu.

43. 1. truncata Clute, Fern Allies, 222-228, 260. 1905.

I. echinospora var. truncata Eaton in Gilbert, List N. Am.
Pterid. 10: 27. 1901.

Corm 2-lobed; leaves 20-40, 6-13 cm. long, stout, rather rigid,
finely tapering, with almost setaceous apex and wide membra-
naceous margin at base; stomata numerous; peripheral strands
lacking; ligule short-triangular; sporangium oblong, 4-6 mm.
long, marked profusely with brown patches of sclerenchyma cells;
velum covering about 14-14 of sporangium; megaspores white,
430-520», rarely 680, in diameter, marked with numerous
blunt spines; microspores 27-33 y long, papillose.

Distribution: Alaska, Vancouver Island.

Specimens examined: :

Alaska: Kodiak, 20 July, 1899, Coville & Kearney Jr. 2336 &
2337 (Mo. Bot. Gard. Herb. and U. 8S. Nat. Herb.), TYPE;
Kodiak, 20 July, 1899, Fernow 2640 (Mo. Bot. Gard.
Herb.).

Vancouver Island: Sproat Lake, J. Macoun (Mo. Bot. Gard.
Herb.) ; Sproat Lake, fresh water, 13 August, 1887, J. Ma-
coun 6 (N. Y. Bot. Gard. Herb.).

Doubtful: Coville & Kearney 386, New Metlakatla, Annette
Isl., Alaska, 4 June, 1899.

In the spinulose megaspores there is as wide a variation in
size, number, and arrangement of spines as in J. Braunu Dur.
with a marked tendency toward elongated, densely crowded,
rather tuberculate structures. For the close arrangement the

[Vol. 9
176 ANNALS OF THE MISSOURI BOTANICAL GARDEN

only rival among the echinate forms is J. Brochoni Motel., in
which the spines are far sharper.

Most of the Alaskan material is immature, but in some of the
specimens mature spores can be found in the soil. The collec-
tion of Coville & Kearney 2336 appears to be made of smaller
plants of the species, their 2337 of larger specimens, with no
notable differences in spores, sculpture, ete.

Sect. 3. CRISTATAE

§ 3. CrisTaTAE. Forms with 2 or 8-lobed corms; producing
megaspores with tubercles or spines, somewhat extended into
ridges, tending toward branching crests on basal face; micro-
spores rough or smooth.

Key To SPECIES

A. Corms 3-lobed.
ae, ica eSiaVelya SICNUCI: ya ee eee eee ee ne oe ee ee 44. I. tripus
be, | heavesstout,, mucronate) 22-222 eh Sea Sele ee a 45. I, Savatiert
B. Corms 2-lobed.
a. Amphibious forms, with stomata; peripheral strands present
or absent.
a. Megaspores with very crowded prominences.
I. Leaves numerous (25-200), usually with peripheral
OVE Se a OE An Ss ore a Pe ae ee ee he eee 46. I. Eatoni
II. Leaves few (8-25), peripheral strands lacking ~__--_-_- 47. I. saccharata
B. Megaspores with less densely crowded prominences.
I. Sculpture consisting of spines somewhat extended to
form jagged crests.
1. Smaller form, leaves 10-30, 9-30 em. long___.--_-__-- 48. I. riparia
2.) larger torm, leaves) Lo—7o, 10-45 em long === oe ee
a Red ei eb De ee ASO hp arid VAL. CONAGENSUS
II. Sculpture consisting of tubercles somewhat extended
to form rounded ridges.
1. Leaves long, more than 16 cm., with peripheral strands___-----
Sipe Ce AD, PN RMU. abe ba TOMER U CE Pee Siw ENE ay ne HED 49. I, Pringlet
2. Leaves short, less than 8 em., lacking peripheral strands__----~-

b. Submerged forms, lacking stomata and peripheral strands.
a. Welum narrow, covering about %4 of sporangium.
I. Megaspores with somewhat confluent, but little

AnAsLOMOsINe \eresis pee ee pe OL ae OE eae ee 1. I. lecustris
iI. Megaspores with crests, forming irregular network on

fovelsbe ll adh eK olsen shed RN ERODE ie hl BS pt EER TEA oS Vile fal) 52. I. occidentalis
B. Velum wider, covering 4-34 of sporangium___----~------ 53. I. Piperi

44.1, tripus A. Br. Monatsber. K. Akad. Wiss. Berlin, 544.
1868; Motel. & Vendr. Actes Soc. Linn. Bord. 36: 361. 1888.

I. phaeospora Dur. Bull. Soc. Bot. Fr. 9: 103. 1864. frde
Moiel. & Vendr.

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE BY rg

Calamaria tripus Kuntze, Rev. Gen. Pl. 2: 828. 1891-93.

Corm conspicuously 3-lobed; bulb of leaves small, bound by
the dark black remains of dying leaves; leaves very slender, not
narrowed above, somewhat obtuse and tough, opaque; stomata
present; peripheral strands absent (?); ligule elongate-deltoid ;
velum none (beyond the acute edge of the fovea); sporangium
without border, pale, becoming dark ashy, beautifully marked
with few schlerenchyma cells; megaspores 400-460 p, dark when
wet or dry, meandriform-roughened on all faces; microspores
35-40 up long, dark with loose exospore, somewhat wing-crested.

Distribution: Swan River, Australia.

Description from Braun.

45. I. Savatieri Franchet, Bull. Soc. Bot. Fr. 31: 395. 1884;
Baker, Fern Allies, 1388. 1887.

Calamaria Savatieri Kuntze, Rev. Gen. Pl. 2: 828. 1891-93.

Corm obscurely 3-lobed, about 15-20 mm. in diameter; bulb
coarse, 2-3 cm. in diameter, bearing loosely imbricated bases of
leaves; leaves stout, subtetragonous, mucronate, about 20 cm.
long in submerged forms, much shorter (hardly 6 cm.) in
emersed plants, very coarse and rigid, broad (7-10 mm. at base),
with wide membranaceous margin; sporangium small, hardly
4 mm. long, ovate or suborbicular, with narrow area; ligule
ovate-deltoid, rough, fuscous; velum incomplete, covering 1/3-
3/4 of sporangium; megaspores white, rough all over surface,
marked finely with anastomosing ridges, more or less elevated;
microspores brown, very finely muricate or almost smooth, cris-
tate on one side.

Distribution: Patagonia, lakes in vicinity of Puerto Bono,
Straits of Magellan.

Description from Franchet.

46. I. Eatoni Dodge, Ferns & Fern Allies of N. Eng. 39.
1896; Bot. Gaz. 23: 32-39. pl. 4-6. 1897; Underwood, Native
Ferns and Allies, 146. 1900.

I. valida Clute, Fern Allies, 236, 260. 1905.

Corm 2-lobed; leaves 25-200, 10-60 cm. in length, much
shorter in summer (10-15 cm. long), coarser in spring forms;
stomata numerous; peripheral strands variable in number, some-

[Vol. 9
178 ANNALS OF THE MISSOURI BOTANICAL GARDEN

times wanting; sporangia oblong, 6-11 mm. long, brown-spotted,
1/6-1/4 covered by velum; megaspores white, 396-520 u, rarely
more, in diameter, with irregular commissural ridges and with
faces marked very irregularly by crowded short meandriniform
elevations, sometimes with rounded teeth; microspores 25-35 pu
long, smooth to slightly papillose.
Distribution: New Hampshire, Massachusetts, New Jersey.
Specimens examined:

New Hampshire: shore of pond, Trickling Falls, Kingston, Aug-
ust, 1895, Dodge (Mc. Bot. Gard. Herb. and Gray Herb.),
TYPE; flats at Kingston, August, 1896, Haton (Mo. Bot.
Gard. Herb.); Kingston, 9 September, 1897, Haton (Mo.
Bot. Gard. Herb. and Gray Herb.) ; sloping bank of a pond,
out of water most of the year, in mixed mud and sand, East
Kingston, September, 1895, Herb. Haton (Mo. Bot. Gard.
Herb. and N. Y. Bot. Gard. Herb.) ; East Kingston, August,
1895, Dodge (Mo. Bot. Gard. Herb.); “East Kingston, on
Powow River, shores of pond, fruiting out of water,” 6 Oc-
tober, 1895, Eaton (Mo. Bot. Gard. Herb.) ; East Kingston,
26 July, 1896, Eaton 351 (Mo. Bot. Gard. Herb.); East
Kingston, August, 1896, Dodge (Mo. Bot. Gard. Herb. and
N. Y. Bot. Gard. Herb.) ; East Kingston, 8 September, 1896,
Eaton 589 (Mo. Bot. Gard. Herb.) ; “The flats,” East Kings-
ton, 28 July, 1896, Dodge (Gray Herb.); East Kingston,
August, 1896, Eaton 163 (N. Y. Bot. Gard. Herb.); East
Kingston, 9 September, 1897, Haton (Mo. Bot. Gard.
Herb.); East Kingston, 10 August, 1900, Dodge (Mo. Bot.
Gard. Herb.) ; submersed, Kingston, August and September,
1897, Eaton 898 (Mo. Bot. Gard. Herb.); grown in pond
at Seabrook from plant collected at Kingston, 1900, Haton
(Mo. Bot. Gard. Herb.); West Epping, Haton 482C (Mo.
Bot. Gard. Herb.) ; Epping, 12 August, 1896, Haton 427 (Mo.
Bot. Gard. Herb.) ; Lamprey River, Epping, August, 1897,
Eaton (Mo. Bot. Gard. Herb.); Newmarket, 19 August,
1899, Haton 217 (Mo. Bot. Gard. Herb.).

Massachusetts: Tuxbury’s Pond, Amesbury, 19 September, 1898, ~
Eaton 919 (Mo. Bot. Gard. Herb.); Parker River, Dodge
(Mo. Bot. Gard. Herb.); Long Pond, North Easton, 23
September, 1903, Eaton (Mo. Bot. Gard. Herb.); without

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 179

location, September 16, 1902, Haton (Mo. Bot. Gard.
Herb.).

New Jersey: Morris Pond, 11 September, 1890, Britton (N. Y.
Bot. Gard. Herb.); in water, 1 ft. deep, Morris Pond, 14
September, 1887, Britton (N. Y. Bot. Gard. Herb.).

47. 1. saccharata Engelm. in Gray, Manual, ed. 5, 676. 1867;
Baker, Jour. Bot. 18: 69. 1880; Motel. & Vendr. Actes Soc.
Linn. Bord. 36: 356. 1883; Engelm. Trans. St. Louis Acad. Sci.
4: 382. 1882; Eaton in Gray, Manual, ed. 7, 60. 1908; Maxon
in Britton and Brown, Ill. Fl. 1: 52. 1918.

I. saccharata var. Palmeri Eaton, Proc. Biol. Soc. Wash. 14:
49. 1901.

I. saccharata var. reticulata Eaton, Proc. Biol. Soc. Wash.
4-495. ESOL.

Calamaria saccharata Kuntze, Rev. Gen. Pl. 2: 828. 1891-93.

Corm 2-lobed, small, much flattened; leaves 8-25, rarely 40,
6-15 cm. long, slender, curved, olive-green, with membranaceous
margin at base, soon disappearing above; stomata numerous;
peripheral strands none; ligule small, cordate at base; sporan-
gium small, 3-5 mm. long, almost as wide as long, with narrow
velum (covering less than 1/5 of sporangium); megaspores
white, 400-520 in diameter, marked with very irregular,
crowded, more or less discontinuous ridges with prominences
somewhat blunt or granular; microspores 23-29 p long (rarely
32), almost smooth.

Distribution: Delaware, Maryland, District of Columbia, Vir-
ginia.

Specimens examined:

Delaware: near Seaford, shores of Nanticoke River, Sussex Co.,
August, 1874, Canby (Mo. Bot. Gard. Herb., Gray Herb.,
and U.S. Nat. Herb.).

Maryland: on tidal mud, Salisbury, shores of Wicomico River,
28 August, 1867, Canby (Mo. Bot. Gard. Herb. and U. S.
Nat. Herb.), Type; shores of Wicomico River below Salis-
bury, 8 September, 1866, Canby (Mo. Bot. Gard. Herb. and
Gray Herb.) ; tidal mud, Salisbury, 28 August, 1867, Canby
(Mo. Bot. Gard. Herb. and U. 8. Nat. Herb.) ; shore of Wico-
mico River near Salisbury, 1 September, 1867, Canby (Gray
Herb.) ; gravelly shore of Wicomico River, Salisbury, 1 Oc-

[Vol. 9
180 ANNALS OF THE MISSOURI BOTANICAL GARDEN

tober, 1868, Commons (U.S. Nat. Herb. and Gray Herb.) ;
Salisbury, 1869, Canby (Mo. Bot. Gard. Herb.); “Mary-
land,” September, 1870, Canby (Gray Herb.); Notley Hall,
1894, Coville 32 (Gray Herb., U. S. Nat. Herb., and N. Y.
Bot. Gard. Herb.); Wicomico River, 14 September, 1895,
Palmer (Mo. Bot. Gard. Herb.); Kent Co., Lloyd’s Creek,
Sassafras River, 12 August, 1895, Palmer (Mo. Bot. Gard.
Herb., Gray Herb., and U. S. Nat. Herb.); same, 29 July,
1896 (Mo. Bot. Gard. Herb.); tidal track, reddish sand,
capped lightly with mud, Elk River (about 80 mi. north of
Nanticoke and Wicomico River), 1894, Palmer (Mo. Bot.
Gard. Herb.) ; Town Point, Elk River, 30 July, 1896, Palmer
(Mo. Bot. Gard. Herb.) ; Cabin Johns Creek, 21 July, 1896,
Palmer (Mo. Bot. Gard. Herb. and U. S. Nat. Herb.);
Cabin Johns Creek, Elk River, 31 July, 1896, Palmer (U.S.
Nat. Herb.) ; between tides, rather common among rocks in
sand, 144 mi. southwest of Havre de Grace, 19 July, 1902,
Shull 66 (Mo. Bot. Gard. Herb., Gray Herb., and U. S. Nat.
Herb.) ; 14 mi. south of Havre de Grace, 19 July, 1902, Shull
67 (U.S. Nat. Herb.) ; mouth of Gunpowder River, 2 Sep-
tember, 1902, Shull 296 (Mo. Bot. Gard. Herb., Gray Herb.,
and U. 8. Nat. Herb.) ; 1/3 mi. above mouth of Little Gun-
powder River, in sand, 3 September, 1902, Shull 305 (Mo.
Bot. Gard. Herb., Gray Herb., and U. S. Nat. Herb.).

Washington, D. C.: shores of Anacostia River, opposité Navy
Yard, 1 September, 1900, Steele (Mo. Bot. Gard. Herb.,
Gray Herb., and U. 8S. Nat. Herb.); tide mud, 5 August,
1898, Steele (Gray Herb.).

Virginia: Hunting Creek, by bridge near its mouth, 22 July, 1888,
Vasey & Coville (U. S. Nat. Herb.); shore of Potomac at
the foot of the Mt. Vernon estate, 4 July, 1889, Coville
(Mo. Bot. Gard. Herb. and U. S. Nat. Herb.); Hunting
Creek, 1 mi. south of Alexandria, 7 September, 1901, Mazon
432 (U.S. Nat. Herb.); 1 mi. south of Alexandria, at right
hand of wagon bridge over Hunting Creek, an arm of the
Potomac, in sand or gravel, in 6 in. water, exposed at ebb
tide, 16 September, 1906, Maxon 3886 (U.S. Nat. Herb.) ;
Hunting Creek, southwest of Alexandria, 11 August, 1902,
Shull 200, 201 (Mo. Bot. Gard. Herb. and U.S. Nat. Herb.) ;
near Hunting Creek, southwest of Alexandria, in shallow

T9223)
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 181

water, 11 August, 1902, Shull 201 (Gray Herb.); so. margin
Four Mile Run, 19 November, 1895, Coville 123 (U.S. Nat.
Herb.) ; tide beach in mud and gravel, mouth of Four Mile
Run between Washington and Alexandria, 5 August, 1898,
Steele (Mo. Bot. Gard. Herb. and U. S. Nat. Herb.) ; Four
Mile Run, 4 mi. south of Washington, D. C., 22 August,
1902, Shull 252 (Mo. Bot. Gard. Herb. and U. S. Nat.
Herb.); Four Mile Run, near Alexandria, abundant be-
tween tidal limits, 12 July, 1905, Ivar Tidestrom (Gray
Herb.) ; Hunting Creek, Alexandria, 13 August, 1910, Dowell
6455 (U.S. Nat. Herb.).

48. I. riparia Engelm. A. Br. in Flora (Regensb. Bot. Zeit.)
29: 178. 1846; Am. Jour. Arts and Sci. 3: 52. 1847; Baker,
Jour. Bot. 18: 69. 1880; Motel. & Vendr. Actes Soe. Linn. Bord.
36: 368. 1883; Engelm. Trans. St. Louis Acad. Sci. 4: 382. 1884;
Macoun, Cat. Canad. Pl. pt. 4: 298. 1888; Eaton in Gray, Man-
ual, ed. 7, 60. 1908; Maxon in Britton and Brown, Ill. FL, ed.
2,52. 1913.

Calamaria riparia Kuntze, Rev. Gen. Pl. 2: 828. 1891-93.

Corm 2-lobed; leaves 10-30, 9-30 cm. long, rather rigid, more
slender than /. lacustris, deep green in color, with membranace-
ous margins but briefly extended; stomata numerous; periph-
eral strands lacking; ligule elongated, with narrow tip, ovate
at base; sporangia spotted with brown cells, oblong, 4-7 mm.
long, with narrow velum (covering sporangia 1/4-1/3); mega-
spores white, 440-660» in diameter, marked with conspicuous
jagged crests, often with isolated peaks standing out sharply,
sometimes anastomosing slightly; microspores cream-colored in
mass, 25-83 » long, tuberculate.

Distribution: southern Canada, New England, south to Dela-
ware and Pennsylvania.

Specimens examined:

Canada: Crow River, northwest of Belleville, Hastings Co., 18
July, 1864, Macoun (Mo. Bot. Gard. Herb. and N. Y. Bot.
Gard. Herb.).

Maine: Cornish, 1859, Chickering 7 (Mo. Bot. Gard. Herb.).

Connecticut: Lantern Hill Pond, North Stonington, 23 July,
1901, Graves & Bissell (Mo. Bot. Gard. Herb.); Lantern
Hill Pond, North Stonington, 23 July, 1901, Bissell (Gray

ISViGlsioae
182 . ANNALS OF THE MISSOURI BOTANICAL GARDEN

Herb.); abundant in mill-race and stiller waters of Mill
River, near tide water, local, Fairfield, 5 September, 1897,
Eames (Gray Herb.).

Vermont: in Connecticut River near Brattleborough, from foot
deep to an inch or less (in fall when river recedes), on a
pebbly bottom where the mud is deposited between the
rocks, 1866, Frost 6 (Mo. Bot. Gard. Herb.) ; Lake Bomo-
seen, W. Hubbardton, 3 October, 1897, Eggleston 1786 (Gray
Herb. and N. Y. Bot. Gard. Herb.); above low water line,
region Lake Bomoseen, Castleton, 5 September, 1909, Dut-
ton 2382 (Gray Herb.).

Massachusetts: Uxbridge, 1831, Robbizis 7 (Mo. Bot. Gard.
Herb.) ; Uxbridge, 1843, Robbins 8 (Mo. Bot. Gard. Herb.) ;
Uxbridge, without date, Robbins 9 (Mo. Bot. Gard. Herb.) ;
Uxbridge, 1848, Robbins 11 (Mo. Bot. Gard. Herb.); Ux-
bridge, 30 August, 1866, Robbins 14 (Mo. Bot. Gard. Herb.) ;
Uxbridge, in a mill pond, 1865, Robbins (Mo. Bot. Gard.
Herb.) ; very shallow part of a cool pond (Capron’s reser-
voir), 4 September, 1869, Robbins (N. Y. Bot. Gard. Herb.) ;
small cold pond (Capron’s fountain), 6 October, 1867, Rob-
bins (N. Y. Bot. Gard. Herb.) ; Uxbridge, 1866, Robbins (N.
Y. Bot. Gard. Herb.) ; some entirely submerged and some in
mud on shore, South Natick, 25 June, 1879, Morong (N.
Y. Bot. Gard. Herb.); ponds, Amherst, September, 1874,
Jesup (Mo. Bot. Gard. Herb.); shallow water, So. Natick,
September, 1878, Morong (Mo. Bot. Gard. Herb.) ; Taun-
ton, Watson’s Pond, 15 September, 1903, Eaton (Mo. Bot.
Gard. Herb.) ; Uxbridge, 31 August, 1907, Haton (Mo. Bot.
Gard. Herb.); Shawshim River, Bedford, 25 August, 1884,
Jenks & Swan (Mo. Bot. Gard. Herb. and Gray Herb.) ; Ne-
ponset River, Paul’s Bridge, Faxon (Gray Herb.) ; Bedford,
without date, Swan (Gray Herb.).

New Jersey: muddy banks of the Delaware River, Camden, Sep-
tember, 1860, D. C. Eaton (Mo. Bot. Gard. Herb.); along
shores of the Passaic River, 6 mi. north of Newark, August,
1858, Ennis (Mo. Bot. Gard. Herb.) ; banks of the Delaware,
above Camden, 1867 (?), Durand (Gray Herb.); shores of
the Delaware, 22 September, 1866, Parker (Mo. Bot. Gard.
Herb.) ; gravelly shore of the Delaware River, between high
and low water mark, Camden, 20 September, 1867, without

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 183

collector (Mo. Bot. Gard. Herb.) ; margin of the Delaware,
opposite Philadelphia, October, 1868, ex. herb. Thurber
(Gray Herb.); shore of the Delaware, between high and
low water, mark, Camden, 7 October, 1877, Parker (Gray
Herb.); Fish House, Delair, 19 August, 1906, Poyser (Mo.
Bot. Gard. Herb.).

Delaware: shores of the Delaware River, 4 mi. above Wilming-
ton, July, 1860, Canby (Mo. Bot. Gard. Herb.); shores of
the Delaware, near low water mark, Newcastle Co., 1862,
Canby (Mo. Bot. Gard. Herb.); shores of the Delaware
River near Wilmington, 1865, Canby (Gray Herb.); Wil-
mington, 29 June, 1866, Canby (Gray Herb.) ; banks of the
Delaware, between high and low water mark, 14 September,
1866, Commons (Mo. Bot. Gard. Herb.); Wilmington, 25
September, 1866, Canby (Gray Herb.); gravelly shores,
Delaware River, between high and low water mark, near
Wilmington, 11 July, 1866, Commons (Mo. Bot. Gard.
Herb.) ; muddy shores of the Delaware River near Wilming-
ton, August, 1867, Canby (Mo. Bot. Gard. Herb.); Wil-
mington, 12 June, 1867, Canby (Mo. Bot. Gard. Herb.) ;
Wilmington, 1882, Canby (Mo. Bot. Gard. Herb.); river
shore below Claymont, 22 June, 1896, Commons (Mo. Bot.
Gard. Herb. and Gray Herb.) ; Delaware River, 1905, Palm-
er (Mo. Bot. Gard. Herb.).

Pennsylvania: inundated by tides, shores of Delaware River,
Gibsonville (Philadelphia), 22 August, 1815, Nuttall (Mo.
Bot. Gard. Herb.); Philadelphia, without date, Haton ez.
herb. Thurber (Gray Herb.); gravelly shore of the Dela-
ware, near Philadelphia, August, 1844, Zantziger (Mo. Bot.
Gard. Herb.), type; Philadelphia, October, 1848, Durand
(Mo. Bot. Gard. Herb.); banks of the Delaware, Philadel-
phia, July, 1860, James (Mo. Bot. Gard. Herb.) ; tidal mud,
Tinicum to 11 mi. below Philadelphia, August, 1864, Smith
(Mo. Bot. Gard. Herb.); banks of Delaware River near
Philadelphia, 18 June, 1866, Durand (Mo. Bot. Gard. Herb.
and Gray Herb.); Delaware River, August, 1894, Palmer
(Mo. Bot. Gard. Herb.) ; banks of Lehigh River, on an is-
land near Bethlehem, in sandy mud of river among and
between stones, 1866, Durand (Mo. Bot. Gard. Herb. and
Gray Herb.) ; along shaded bank of Lehigh River near Beth-

[Vol. 9
184 ANNALS OF THE MISSOURI BOTANICAL GARDEN

lehem, August, 1882, Rau ( Mo. Bot. Gard. Herb.);
gravelly banks, tidal margin of the Delaware, opposite
Chester, August, 1894, Palmer (Mo. Bot. Gard. Herb.) ;
shores of Delaware, opposite Chester, 22 August, 1896, with-
out collector (U. 8. Nat. Herb.); shores of Delaware, op-
posite Chester, 1 August, 1896, Palmer (Mo. Bot. Gard.
Herb.).

48a. Var. canadensis Engelm. Trans. St. Louis Acad. Sci. 4:

383. 1884.

I. Dodgei Eaton, Fern Bull. 6: 6. 1898.
I. Dodgei var. Robbinsu Eaton, Rhodora 10: 42. 1908.
I. canadensis Eaton, Proc. U. 8. Nat. Mus. 23: 650. 1901;

Bull. Torr. Bot. Club 30: 359-362. 1903.

I. canadensis var. Robbins Eaton, Rhodora 5: 7. 1908.

Usually larger than the species; leaves 15-75, 10-45 cm. long,
with rather prominent membranaceous margins; stomata nu-
merous; peripheral strands variable (2-4) or lacking; ligule cor-
date at base, subulate; sporangia 5-8 mm. long, partly covered
by velum (14-14); megaspores white, 440-650 in diameter,
with usually scattered, thin, spiny crests, brief and discontinu-
ous, though sometimes anastomosing, particularly on the basal
face; microspores 27-87 » long, minutely roughened to decidedly
spinulose.

Distribution: eastern Canada, Massachusetts, Connecticut.

Specimens examined:

Canada: Petites Chaudiéres, near Ottawa, emersed, 11 August,
1917, Bro. Rolland 6230 (Mo. Bot. Gard. Herb. and N. Y.
Bot. Gard. Herb.) ; Brigham’s Creek, Hull, 29 August, 1894,
Macoun 14213 (Gray Herb.); near Hull, 4 October, 1907,
Macoun 76921 (Gray Herb. and N. Y. Bot. Gard. Herb.) ;
Ottawa River below railway bridge, Hull, 18 August, 1911,
Macoun 84084 (Gray Herb. and N. Y. Bot. Gard. Herb.) ;
mud in places that had been overflowed in spring, Hull, Oc-
tober, 1890, Macoun (N. Y. Bot. Gard. Herb.).

New Hampshire: Kingston, 26 July, 1896, Haton 351 (Mo. Bot.
Gard. Herb.) ; Kingston, 28 July, 1896, Eaton 362 (Mo. Bot.
Gard. Herb.) ; East Kingston, 9 September, 1897, Haton 900
(Mo. Bot. Gard. Herb.); flats of Powow River, Trickling
Falls, Kingston, 28 July, 1896, Haton (Mo. Bot. Gard.

1922

es

PFEIFFER—MONOGRAPH OF THE ISOETACEAE 185

Herb.) ; Kingston, September, 1897, Eaton 942 (Mo. Bot.
Gard. Herb.).

Massachusetts: Uxbridge, 1845, Robbins 10 (Mo. Bot. Gard.
Herb.) ; Watson’s Pond, Taunton, 15 September, 1903, Za-
ton (Mo. Bot. Gard. Herb.) ; Leach’s Pond (Wilbor’s Pond),
(Mass.?), September, 1906, Haton (Mc. Bot. Gard. Herb.) ;
Uxbridge, 51 August, 1907, Haton (Mo. Bot. Gard. Herb.) ;
rare, muddy shores, pool in Peabody Cemetery, 10 October,
1915, Andrews (Gray Herb.).

Connecticut: half submerged on shore of Chapman’s Pond, Gro-
ton, 30 August, 1896, Graves 144 (Mo. Bot. Gard. Herb.);
mill-race in Mill River, Fairfield, 19 July, 1905, Eames 5294
(Gray Herb.).

New Jersey: Pt. Pleasant, September, 1899, Best (Mo. Bot.
Gard. Herb.); Pt. Pleasant, 4 July, 1899, Best & Crawford
(Mo. Bot. Gard. Herb.).

The species and the variety are very close; the distinction is
based chiefly on the tendency to larger size in the variety which
is evinced in more and longer leaves. There is also an inclina-
tion toward larger microspores, though the ranges overlap suf-
ficiently so that this too cannot be used absolutely. The Ux-
bridge material of Robbins is of the intermediate sort, with
somewhat bigger microspores, but plant size according well with
the general range of the species.

49. I. Pringlei Underw. Zoe 1: 98. 1890.

Corm 2-lobed; leaves 4-20, 16-30 cm. long, firm, fine, taper-
ing, with membranaceous margin only briefly extended (1 cm.)
above level of the sporangium; stomata abundant; peripheral
strands numerous, 6 conspicuous and 6-10 accessory groups;
hgule triangular, short and wide; sporangium large, up to 10-12
mm. in length in large individuals, partly covered by narrow
velum ; megaspores chalky white when dry, tan when moist, 460-
550 » in diameter, rarely 650», marked with high tubercles, oc-
casionally extended into brief rounded crests; commissural
ridges irregular in outline; microspores fawn-colored, 35-42 y
long, sometimes showing tendency toward winged condition.

Distribution: Mexico.

Specimens examined:

Mexico: in grassy springy places near Guadalajara, State of

CVol. 9
186 ANNALS OF THE MISSOURI BOTANICAL GARDEN

Jalisco, 1 November, 1890, Pringle 3333 (Mo. Bot. Gard.
Herb., Gray Herb., and U.S. Nat. Herb.).

50. I. Flettii Pfeiffer, comb. nov.

I. echinospora var. Flettii Eaton, Fern Bull. 11:85. 1903.
(name only); Eaton, Fern Bull. 13: 51. 1905.

Corm 2-lobed; leaves 15-30, 5-8 cm. long, coarse, tapering,
spreading or recurved, with wide basal sheath extending upward
one-third of leaf length; stomata present; peripheral strands
lacking; ligule blunt triangular; sporangia oblong, 4 mm. long,
with velum developed less than half; megaspores 480-570 p in
diameter, marked with coarse low tubercles and short crests,
usually somewhat distant; microspores 29-83 u long, finely spin-
ulose.

Distribution: Washington.

Specimens examined:

Washington: Spanaway Lake, Pierce Co., August, 1895, Piper
2125 (Mo. Bot. Gard. Herb. and N. Y. Bot. Gard. Herb.) ;
shore, Spanaway Lake, 17 September, 1899, Allen (N. Y.
Bot. Gard. Herb.) ; amphibious, lake shore in gravel, Span-
away Lake, 7-8 October, 1899, Flett 949 (Mo. Bot. Gard.
Herb. and U. 8. Nat. Herb.), Type; submerged, above in
driest season, Spanaway Lake, 22 September, 1900, Flett
(N. Y. Bot. Gard. Herb.); Spanaway Lake, under water,
20 May, 1911, Bardell (U. S. Nat. Herb.) ; Spanaway Lake,
under water, 20 May, 1911, Zeller (U. S. Nat. Herb.).

51. I. lacustris L. Sp. Pl. 1100. 1753; Baker, Jour. Bot. 18:
67. 1880, and Fern Allies, 125. 1887; Motel. & Vendr. Actes
Soe. Linn. Bord. 36: 325. 1883.

I. leiospora Klinggraff. Schr. Nat. Ges. Danzig 6*: 20. 1884.

Calamaria lacustris Kuntze, Rev. Gen. Pl. 2: 828. 1891-93.

Corm 2-lobed; leaves 8-40, 8-18 cm. in length, quadrangular
in cross-section, erect, coarse, acutely pointed, dark green, with
membranaceous border very wide at base, but not greatly pro-
longed beyond level of the sporangium; stomata and peripheral
strands lacking; ligule usually short, triangular; sporangia 4-7
mm. long, with narrow velum; megaspores white, 500-700 » in
diameter, marked with numerous somewhat confluent, but little

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 187

anastomosing crests; commissural ridges irregular; microspores

yellow-brown, 31-45 » long, smooth.

Distribution: British Isles, north and central Europe.
Specimens examined:
British Isles:

Scotland: Loch Brandy, Clova, Croall 1418 (Mo. Bot. Gard.
Herb. and N. Y. Bot. Gard. Herb.); Loch Callater, Aber-
deenshire, July, 1856, Croall (U. S. Nat. Herb.); Loch
Cluny, Perthshire, September, 1850, Walker-Arnott (N. Y.
Bot. Gard. Herb.); “Scotland,’ Ward (N. Y. Bot. Gard.
Herb.); Loch Brandy, Forfarshire, August, 1837, Brand
(Soc: Bot.. Hdin. 183) (N: Y. Bot. ‘Gard. Herb.); Loch
Brandy, Clova, August, 1887, Balfour (N. Y. Bot. Gard.
Herb.) ; in a little lake near the Trossach’s toward Callan-
der, July, 1871, without collector (Gray Herb.); Loch Lo-
mond, without date or collector (Gray Herb.).

Wales: Llanberis, 10 June, 1870, Butter (Mo. Bot. Gard. Herb.) ;
Lake Llyn Padark, 20 August, 1862, Gay (Gray Herb.) ;
Crom y glo, North Wales, 12 November, 1862, Gay (?) (Mo.
Bot. Gard. Herb. and Gray Herb.); Phrynon Vrech, 23
August, 1862, without collector (Mo. Bot. Gard. Herb.).

France: Lac de Gerardmer, Vosges, 16 July, 1858, Cosson (Mo.
Bot. Gard. Herb.) ; Lac de Guéry, Puy-de-Diéme, 23-24 Aug-
ust, 1861, Durieu (Mo. Bot. Gard. Herb.); Lae de Guéry,
24 August, 1861, Gay (Gray Herb.) ; Lac de Guéry, Puy-de-
Déme, August, 1890, Hy (Mo. Bot. Gard. Herb.); Lac de
Gerardmer, 15 October, 1856, Jacquel (Mo. Bot. Gard.
Herb.) ; Lae de Guéry au Mont Dore, 16 August, 1877, Al-
lard (U.S. Nat. Herb.) ; Lac de Gerardmer, near St. Dié, at
bottom of water on granitic soil, 25 September, 1851, Billot
(U.S. Nat. Herb.) ; in Lake Gerardmer, August, 1864, Perrin
Gray Herb. and N. Y. Bot. Gard. Herb.) ; mountain lake,
Chauvet, in Arvernia, 27 August, 1861, Gay (Gray Herb.) ;
Lac de Bruyeres, dans les Vosges, Hornung (N. Y. Bot.
Gard. Herb.); Longemer, 2 July, 1881, Study (N. Y. Bot.
Gard. Herb.); in bottom of Lakes Gerardmer, Longemer,
and Retournemer, all the year (Stirp. Crypt. Vog.-Rhen.,
1810-26), Mougeot & Nestler 111 (N. Y. Bot. Gard. Herb.) ;
lakes of the Vosges, 1833, Mougeot (N. Y. Bot. Gard.
Herb.); in deep pools and ponds, through almost all the

[Vol. 9
188 ANNALS OF THE MISSOURI BOTANICAL GARDEN

year, Desmaziéres 597 (N. Y. Bot. Gard. Herb.); lac de
Guéry, near Mont Dore, Puy-de-Dome, 14 September, 1879,
Heribaud (N. Y. Bot. Gard. Herb.).

Spain: Lac de Bassibé, valley of the Rio Malo, Pyrenees Espag-
noles, 11 August, 1880, Lagrave (N. Y. Bot. Gard. Herb.).

Norway and Sweden: lakes of Norway, Blytt 1958 (Mo. Bot.
Gard. Herb.); “N. Vi. s: N Vassviken vid Ribbingstrof,”
11 August, 1870, (Ydre) Dusen (U.S. Nat. Herb.) ; “Vaer-
endia, Dref,’ August, 1879, Hyltén-Cavallius 1771 (U. 8.
Nat. Herb.) ; “Augnil Hoysjs Mortsjord,” July, 1887, ran-
berg (U.S. Nat. Herb.) ; Upland near Malaren, July, Varn-
berg (Mo. Bot. Gard. Herb. and Gray Herb.) ; “in Suecica”,
Areschoug (Gray Herb.); Uplandic, Anderssen (Mo. Bot.
Gard. Herb.); “Smolandia Moheda,” August, 1875, Hyl-
tén-Cavallius (N. Y. Bot. Gard. Herb.); “Vedvson”’, Juiy,
1868, ex herb. Per Larson (N. Y. Bot. Gard. Herb.) ; Smol.
Moheda, lake, sand, August, 1881, Hyltén-Cavallius (N. Y.
Bot. Gard. Herb.); near Stockholm, 1842, Wicketson (N.
Y. Bot. Gard. Herb.).

Denmark: Madum 86, 13 August, 1889, Bergesen (Mo. Bot.
Gard. Herb.); Jutland, Le Roy (N. Y. Bot. Gard. Herb.) ;
Landsee bei Espenkrug, Klinsmann (Mo. Bot. Gard. Herb.).

Germany: Grosser Teich (east side), Riesengebirge, August,
1866, Engler (N. Y. Bot. Gard. Herb.); Riesengebirge,
August, 1866, Ascherson (Mo. Bot. Gard. Herb.); Titisee,
Baden, August, 1846, Braun (Mo. Bot. Gard. Herb.); Ti-
tisee, May, 1846, Braun (Mo. Bot. Gard. Herb.); Ti-
tisee, July, 1864, Braun (Mo. Bot. Gard. Herb. and Gray
Herb.) ; near Biitow, e. Pomerania, 1862, Braun (Mo. Bot.
Gard. Herb.); near Heringsdorf, I. of Usedom, September,
1863, Braun (Mo. Bot. Gard. Herb.); in Lake Wjelling.
near Biitow, 1867, Doms (Gray Herb.) ; Biitow, in Wjelling
See, Pomerania, August, 1866, Doms (Mo. Bot. Gard.
Herb.); Heringsdorf, Usedom, August, Marrson 14 (Mo.
Bot. Gard. Herb.); in Grosser Krebssee, near Herings-
dorf, Usedom, September, 1864, Brawn (Gray Herb.);
Kleiner Krebssee, near Sallentin, I. of Usedom, Septem-
ber, 1864, Braun (Gray Herb., U. S. Nat. Herb., and N.
Y. Bot. Gard. Herb.); Heringsdorf, in Kleiner Krebssee,
9 August, 1896, Retter (U. S. Nat. Herb.); Grosser

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 189

Krebssee, near Heringsdorf, I. of Usedom, 9 September,
1902, without collector (U. S. Nat. Herb.); ‘“Feldsee bei
Freiburg,”. 7 July, 1864, Reess (U. S. Nat. Herb.);
Titisee near Freiburg, 1866, Magnus (U. S. Nat. Herb.) ;
Titisee, Schwarzwald, 187-, Reinsch (U. S. Nat. Herb.) ;
Feldbergsee, Schwarzwald, 30 June, 1868, Zickendrath
(N. Y. Bot. Gard. Herb.); on stony bottom of Feldsee,
Feldberg, Schwarzwald, 17 July, 1834, Meisner (N. Y.
Bot. Gard. Herb.); Einfelder See, Lauenburg, Schles-
wig-Holstein, Nolte 1601 (N. Y. Bot. Gard. Herb.) ; Titisee,
1000 m., September, 1885, Christ (N. Y. Bot. Gard. Herb.) ;
20-50 cm. below water surface, stony substratum, in Stein-
see near Kirchseeon, upper Bavaria, July, 1900-01, and July
& August, 1902, Hepp 599 (Gray Herb.) ; in lake, Gardsee,
Ratzeburg, September, 1864, Reinke (Gray Herb.) ; Grosser
Teich, Riesengebirge, Silesia, July, 1866, Milde (Gray
Herb.) ; Grosser Teich, Riesengebirge, 31 July, 1874, Buch-
enau (Gray Herb.); Wiggoda in Moritzsee, West Prussia,
10 May, 1885, Litzow (Gray Herb.); Gr. Ottalsiner See,
West Prussia, 10 August, 1885, Liitzow (Gray MHerb.);
Schluchsee in Black Forest, September, 1867, without col-
lector (Gray Herb.); Riesengebirge, 24 August, 1884,
Hieronymus (Mo. Bot) Gard. Herb.); near Danzig, W.
Prussia, 1854, Klebsman (Mo. Bot. Gard. Herb.) ; millpond,
“Lohmiille’, near Lockstedter Lager, Holstein, August, 1886,
without collector (Mo. Bot. Gard. Herb.).
Bohemia: Bistritzer See, near Eisenstein, Celakovsky 1503 (U.
S. Nat. Herb. and Gray Herb.).
Austria: “Grosser Teich,” Sudetic Mts., Milde (Mo. Bot. Gard.
Herb.).
Finland: Northern Lavonia, Kvopio, 26 July, 1901, Budden (U.
S. Nat. Herb.) ; region of Abo “par. Lojo” in lacu Hormasjo,
6 September, 1893, Boldt 17 (Mo. Bot. Gard. Herb.) ; same
station, 27 August, 1909, Boldt 418 (Mo. Bot. Gard. Herb.).
Russia: St. Petersburg, “Hellgriindiger See in Lewaschweo,”
2-19 August, 1898, Poring (U. S. Nat. Herb.).

52. I. occidentalis Hend. Bull. Torr. Bot. Club 27: 358. 1900.

I. lacustris var. paupercula Engelm. Trans. St. Louis Acad.
Sci. 4: 377. 1882.

[Vol. 9
190 ANNALS OF THE MISSOURI BOTANICAL GARDEN

I. paupercula (Engelm.) Eaton. Proc. U. S. Nat. Mus. 28:

649. 1901, and in Gilbert, List N. Am. Pterid. 10: 28. 1901.

Corm 2-lobed; leaves commonly 9-30, rarely 60, 5-20 cm. long,
dark green, rigid, gradually tapering, with wide membranaceous
border at base, extending 2-3 times length of sporangium above
level of latter; peripheral strands and stomata lacking;) ligule
short-triangular; sporangia almost orbicular, 5-6 mm. long, with
narrow velum (covering about 1/3 of sporangium) ; megaspores
cream-colored, 525-640 in diameter, marked with low con-
spicuous irregular crests, chiefly simple on the apical faces,
branching to form irregular network on basal face; microspores

24-42 4 long, spinulose.

Distribution: Idaho, Wyoming, Colorado, California.

Specimens examined:

Idaho: in water from 6 in. to 6 ft. deep, Lake Coeur d’Alene, 22
August, 1897, Henderson 2979 (Mo. Bot. Gard. Herb.) ; in
2 ft. of water, Lake Coeur d’Alene, August, 1898, Hender-
son (Mo. Bot. Gard. Herb.); in 2 ft. of water, Lake Coeur
d’Alene, August-September, 1897, Henderson 4786 (Gray
Herb.).

Wyoming: Yellowstone Park, 1885, Tweedy 416 (U. S. Nat.
Herb. and Gray Herb.) ; growing in deep water at north end
of Yellowstone Lake, 16 August, 1900, Bessey 1 (N. Y. Bot.
Gard. Herb.).

Colorado: “covering the bottom of Grand Lake in granitic sand,
3—4 ft. under the surface of water, abundant, meadow-like,
Middle Park,” 5 August, 1881, Engelmann (Mo. Bot. Gard.
Herb.).

California: Donner Lake, September, 1887, Curran (Mo. Bot.
Gard. Herb. and N. Y. Bot. Gard. Herb.); Donner! Lake,
Shockley (Mo. Bot. Gard. Herb.) ; Castle Lake, mountains
about the headwaters of the Sacramento River, alt. 6000 ft.,
14 August, 1881, Pringle (Mo. Bot. Gard. Herb. and Gray
Herb.).

53. I. Piperi Eaton, Fern Bull. 13: 51. 1905; name only in Fern |
Bull. 11: 85. 1903;- Piper, Contr. U. 8. Nat.*Herb. 12; 33:
1906.

I. occidentalis var. Piperi (Eaton) Nelson & MacBride, Bot.
Gaz. 61: 30. 1916.

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 191

Corm 2-lobed; leaves 8-26, 3-10 cm., rarely 15 cm., long, medi-
um fine, erect or somewhat spreading, taper-pointed, broadly
winged for twice length of sporangium; peripheral strands and
stomata lacking; ligule short, triangular, ovate; sporangia 4-5
mm. long, with variation in width of velum from 1/3 to 2/3 of
sporangium; megaspores white, 540-800 in diameter, marked
with points or tubercles and short ridges, sometimes slightly
serpentine; microspores 29-35 yu, rarely 42 y, long, papillose.

Distribution: Washington.

Specimens examined:

Washington: Seattle, 11 July, 1889, Piper (Mo. Bot. Gard.
Herb.); Seattle, 11 July, 1889, Smith (Mo. Bot. Gard.
Herb.) ; Lake Washington, near Seattle, 11 July, 1889, Piper
& Smith 651 (N. Y. Bot. Gard. Herb.) ; Green Lake, King
Co., 12 July, 1895, Piper 2317 (Mo. Bot. Gard. Herb. and
N. Y. Bot. Gard. Herb.), Type; mostly submerged in clear
lake, Five Mile Lake, Tacoma, 3 October, 1902, Flett 2034
(Mo. Bot. Gard. Herb., U. S. Nat. Herb., and N. Y. Bot.
Gard. Herb.); Lake Washington, Seattle, August, 1907,
Piper & Hungate (U. S. Nat. Herb.); submerged, Lake
Crescent, 20 August, 1911, Webster (U. S. Nat. Herb.); in
Green Lake, near Seattle, June, 1891, Piper 1102 (N. Y. Bot.
Gard. Herb.).

It is possible that J. Piperi Eaton and I. occidentalis Hend.
may be more closely related than as adjacent species. A slight
difference in habit of the leaves (more gradual tapering in J.
occidentalis, coupled with greater length), a difference in spore
sizes, with J. Piper: tending to show the larger megaspores and
smaller microspores, and a simpler form of sculpture on J. Piperi
compared with the anastomosing ridges of J. occidentalis, and a
tendency toward wider velum in J. Piperi, serve to distinguish
these two submerged species.

Sect. 4. RETICULATAE

§ 4. ReticutatTar. Forms with 2-8 lobed corms; producing
megaspores evidently reticulate, at least on basal face; micro-
spores smooth or rough.

[Vol. $
192 ANNALS OF THE MISSOURI BOTANICAL GARDEN

Key To SPECIES

A. Corms 2-lobed.
a. Submersed forms, stomata none or rare.
a. Megaspores chiefly 600-800, in diameter.
I. Spore markings irregular, sharp crests_____--_-_-_- 64, I, macrospora
II. Spore markings prominent, rounded ridges--___.__-__---------~--
Ne eye etn alfa anne he Meet ata Ee a pep IE ee 54a. I. macrospora f. hieroglyphica

B. Megaspores chiefly 460-600, in diameter_____-_--~- 55. I, Tuckerman
b. Amphibious forms, stomata at least near leaf tips.
GV LeAvesmens chan Stemi ilon ese =e See eee 56. I. foveolata
B. Leaves chiefly more than 18 em. long.

I. Megaspores large, over 580, in diameter__-_-___-- 57. I. Martu

II. Megaspores usually less than 580 » in diamieter.
1. Spore surface reticulate with narrow ridges, 400-
570 w in diameter.
*Velum narrow, covering less than 14 of sporangium_58. I. Engelmanni
**Velum covering 1%4—-% of sporangium__----~-~- 58a. I. Engelmann
var. caroliniana
2. Spore surface reticulate with rounded ridges, 360-
4904) aneNdiametor, sine = 2 On Siar es Ree a 59. I. azorica
B. Corms 3-lobed.
a. Aquatic, lacking velum.

ay heriphoralystrands presente ee ae eee ee 60. I. japonica
Bp: \Porpheral strands jackie tee ee a eee 61. I. Wormaldu
b. Terrestrial, with complete: vyelum. ./-..-----.-.-.---—.-- 62. I. Duriaet

54.1. macrospora Dur. Bull. Soc. Bot. Fr. 11: 101. 1864;
Clute, Fern Allies, 224. 1905; Eaton in Gray, Manual, ed. 7, 58.
1908; Maxon in Britton & Brown, Ill. Fl., ed. 2, 1: 50. 1918.

I. lacustris Engelm. Trans. St. Louis Acad. Sci. 4: 877. 1882;
Motel. & Vendr. Actes Soc. Linn. Bord. 36: 325. 1883; Baker,
Jour. Bot. 18: 67. 1880.

I. Harvey: Eaton, Fernwort Papers, 11. 1900.

I. Tuckerman var. Harvey Clute, Fern Allies, 226. 1905.

I. heterospora Eaton, Fernwort Papers, 8. 1900.

I. macrospora var. heterospora Eaton, Rhodora 10: 42. 1908.

I. Tuckermani heterospora Clute, Fern Allies, 227, 260. 1905.

Corm 2-lobed; leaves usually 13-40, occasionally more numer-
ous, 5-22 em. in length, rigid, slightly to decidedly coarse, ab-
ruptly tapering to apex; peripheral strands lacking; stomata ab-
sent or very rare; ligule short triangular; sporangia 3-5 mm.
long, with narrow velum; megaspores white, 600 (550)—899 u, or
more in rare cases, with sculpture of irregular ridges more or !ess
parallel, with little confluence on upper faces, anastomosing,
sometimes with clear reticulations on the lower face; microspores
338-45 (50) u long, short spinulose.

Distribution: Newfoundland west to Minnesota.

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 193

Specimens examined:

Newfoundland: in shallow water of sandy pond, Torbay, 1901,
Howe & Lang 1424 (N. Y. Bot. Gard. Herb. and Gray
Herb.) ; Whitbourne, 8 August, 1911, Fernald & Wiegand
4409 (Gray Herb.).

Quebec: in 2-6 dm. water, rooting in close-packed granite gravel,
Lac des Americains, alt. 675 m., western base of Table-Top,
Mt. Gaspé, 1-2 August, 1906, Fernald & Collins 155 (Mo.
Bot. Gard. Herb., Gray Herb., and Univ. Minn. Herb.); al-
pine lakes, alt. 900-1000 m., Lac Fortin, Table-Top, Mt.
Gaspé Co., 10 August, 1906, Fernald & Collins 319 (Gray
Herb.) ; Lac 43, Mt. Gaspé Co., 4 August, 1906, Fernald &
Collins 317 (Gray Herb.).

Nova Scotia: in shallow water, sandy soil, lake, North Sydney,
Cape Breton, 1901, Howe & Lang 763 (N. Y. Bot. Gard.
Herb.); Warren Lake, Cape Breton Isl., 15 August, 1914,
Nichols 877 (Gray Herb.); cobbly margins of east branch
of Tusket River, Gavelton, Yarmouth Co., 4 September,
1920, Fernald, Long & Linder 19625 (Mo. Bot. Gard. Herb).

Maine: brook flowing into north end of Jordan’s Pond, Mt.
Desert I., 22 July, 1889, Redfield 2726 (Mo. Bot. Gard.
Herb.); under water, Somes Stream, Mt. Desert L.,
27 July, 1892, Rand (Mo. Bot. Gard. Herb.); Deer
Brook Beach, Jordan Pond, 23 August, 1892, Rand
(Mo. Bot, Gard. Herb.); south shore of Jordan Pond,
10 September, 1894, Rand 3 (Mo. Bot. Gard. Herb.); in
shallow water where a cold spring enters the pond, North-
west Pond, north Franklin Co., 14 July, 1895, Coville 83
(N. Y. Bot. Gard. Herb. and U. S. Nat. Herb.); in 2 ft.
water, gravelly bottom, Kennebago Lake, 5 mi. north of
Rangeley, 12 July, 1895, Coville 78 (N. Y. Bot. Gard. Herb.
and U. 8. Nat. Herb.) ; Penobscot River, Orono, September,
1895, F. L. Harvey 1 (N. Y. Bot. Gard. Herb.); Bubble
Pond, Mt. Desert I., 11 September, 1895, Rand 2 (Mo. Bot.
Gard. Herb.); Pushaw Pond, Oldtown, August, 1895, Har-
vey 2 (N. Y. Bot. Gard. Herb.) ; Pushaw Pond, 21 August,
1899, F. L. Harvey (U. 8. Nat. Herb. and Mo. Bot. Gard.
Herb.); Pushaw Pond, Oldtown, 21 August, 1899, L. H.
Harvey 1411 (U. 8S. Nat. Herb.); rocky shore, “Lake
Cowles,” Mt. Ktaadn, 15-30 August, 1902, Cowles & Harvey

[Vol. 9
194 ANNALS OF THE MISSOURI BOTANICAL GARDEN

1 (Mo. Bot. Gard. Herb.) ; Lower Basin Pond, Mt. Ktaadn,
15-30 August, 1902, Harvey 3 (Mo. Bot. Gard. Herb.) ;
growing in 18 in. water at unusually low. stage of water,
Pushaw Pond, Orono, 17 September, 1905, Knight 14 (Mo.
Bot. Gard. Herb. and Gray Herb.).

New Hampshire: Echo Lake, Franconia Mt., 17 September,
1856, Engelmann (Mo. Bot. Gard. Herb.).

Vermont: near old mill, east shore and Long Cove, W:lloughby
Lake, 3, 5, 7 August, 1907, Winslow (Mo. Bot. Gard. Herb.) ;
Willoughby, 2 September, 1900, Lovery (Gray Herb.) ; shore
of Silver Lake, Leicester, 10 July, 1910, Dutton 787 (Mo.
Bot. Gard. Herb.).

Massachusetts: Fresh Pond, north side, 20 August, 1867, Boott
11 (Mo. Bot. Gard. Herb.) ; same station and date, without
number (Gray Herb.) ; same station, 12 August, 1868, Boott
(N. Y. Bot. Gard. Herb.) ; Uxbridge, without date, Robbins
1 (N. Y. Bot. Gard. Herb.).

New York: Catskill Mts., Schweinitz (Mo. Bot. Gard. Herb.),
probably typr; Third Lake, Fulton Chain, September,
1899, Underwood (N. Y. Bot. Gard. Herb.); Clear Lake,
south of Elk Lake, Adirondacks, 4 September, 1894, Britton
(N. Y. Bot. Gard. Herb.).

Michigan: small lake near Douglas Lake, Cheboygan Co..
August, 1918, Praeger (Mo. Bot. Gard. Herb.) ; Isle Royale,
6 August, 1901, Cooper 26 (Gray Herb.); in 1-2 ft. water,
Vincent Lake, Cheboygan Co., 15 August, 1917, Ehlers 621
(Gray Herb.); Vincent Lake, 30 July, 1918, Ehlers 817
(Mo. Bot. Gard. Herb.).

Minnesota: Devils Track Lake, Cook Co., 28 August, 1901, Lyon
(Mo. Bot. Gard. Herb.).

54a. Forma hieroglyphica Pfeiffer, comb. nov.

I. hieroglyphica, Eaton, Fernwort Papers, 10. 1900.

Habit of the species; megaspores 560-720 » in diameter, rare-
ly less, marked with prominent rounded or smooth ridges, slight-
ly reticulate on upper faces, decidedly so on lower, sometimes
naked near commissural ridges; microspores as in species.

Specimens examined:

Maine: St. Francis Lakes between Maine and Canada, 31 July,
1880, Pringle (Mo. Bot. Gard. Herb., U. 8. Nat. Herb., Gray

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 195

Herb., and N. Y. Bot. Gard. Herb.), Typr; in 4 ft. of water
off the dock, Maneskootuk, Rangeley Lake, 7 July, 1895,
Coville 62 (U.S. Nat. Herb. and N. Y. Bot. Gard. Herb.) ;
Moosehead Lake, September, 1899, F. L. Harvey 4 (Mo.
Bot. Gard. Herb.).

55. I. Tuckermani A. Br. acc. Engelm. in Gray, Manual, ed.
5, 676. 1867; Engelm. Trans. St. Louis Acad. Sci. 4: 378. 1882;
Motel. & Vendr. Actes Linn. Soc. Bord. 36: 388. 1883; Baker,
Jour. Bot. 18: 68. 1880, and Fern Allies, 126. 1887; Under-
wood, Native Ferns and Fern Allies, 122. 1882; Macoun, Cat.
Canad. Pl. pt. 4: 293. 1888; Eaton in Gray, Manual, ed. 7, 59.
1908; Britton & Brown, Ill. Fl., ed. 2, 1: 51. 1913; Clute, Fern
Allies, 225. 1905.

I. Tuckermani var. borealis Eaton, Fernwort Papers, 10. 1900.

Calamaria Tuckermant Kuntze, Rev. Gen. Pl. 2: 828.
1891-93.

Corm 2-lobed, rarely 3; leaves 5-38, 3-18 cm. long, very
slender, tapering, olive-green, outer leaves frequently recurved;
stomata lacking or few in number; peripheral strands none;
sporangia orbicular to oblong, 2-5 mm. long, often brown-spot-
ted;; velum incomplete, covering about 1/3 of sporangium;
megaspores white, 460-600 u, rarely 650, in diameter, with
upper segments marked with somewhat parallel and branching
thin ridges, chiefly irregular at margins, lower segment with
reticulate ridges; microspores 26-34, rarely more (40) in
length, smooth to minutely papillose.

Distribution: Labrador, Newfoundland, Quebec, Nova Scotia.
Maine, New Hampshire, Vermont, Massachusetts, Connecticut.

Specimens examined:

Labrador: pond, Triangular Harbor, 23 August, 1882, Allen (Mo.
Bot. Gard. Herb.).

Newfoundland: in 3-6 in. water, Quiddy Viddy Lake, Robinson
& Schrenk 239 (Mo. Bot. Gard. Herb., U. S. Nat. Herb., N.
Y. Bot. Gard. Herb., Univ. Minn. Herb., and Gray Herb.).

Quebec: on firm clay bottom, small ponds among Silurian hills

‘, _ back of\Birchy Cove)(Curling), 11 August, 1910, Fernald &
Wiegand 2404 (Gray Herb.); emersed, muddy border of a
shallow brook, Lewisport, south shores of Notre Dame Bay,
17 August, 1911, Fernald & Wiegand 4402 (Gray Herb.).

[Vol. 9
196 ANNALS OF THE MISSOURI BOTANICAL GARDEN

Nova Scotia: in Pleasant Lake, Springfield, 16 August, 1910,
Macoun 81092 (Gray Herb.); pond, North Sydney, Cape
Breton Isl., 14 July, 1888, Macoun 14223 (in part) (Gray
Herb. and N. Y. Bot. Gard. Herb.) ; Boylston, August, 1890,
Hamilton 81051 (in part) (Gray Herb.) ; in a brook, Bridge-
water, 28 July, 1910, J. Macoun 81091 (Gray Herb.) ; shal-
low water of Midway (Centreville) Lake, Centreville, Digby
Co., 22 August, 1920, Graves & Linder 19621 (Mo. Bot.
Gard. Herb.) ; quiet pools in Little River and pond holes in
savannahs east of Tidville, Digby Co., 22 August, 1920,
Fernald & Long 19620 (Mo. Bot. Gard. Herb.); shallow
water at sandy margin of Great Pubnico Lake, Yarmouth
Co., 6 September, 1920, Fernald, Long & Linder 19627 (Mo.
Bot. Gard. Herb.) ; peaty margin of Kegeshook Lake, Yar-
mouth Co., 8 October, 1920, Fernald & Linder 19630 (Mo.
Bot. Gard. Herb.); peaty and muddy, dried-out pond-hole
near the head of St. John Lake, Springhaven, Yarmouth Co.,
8 October, 1920, Fernald & Linder 19631 (Mo. Bot. Gard.
Herb.); shallow water of Everitt Lake, 10 August, 1921,
Fernald & Long 23109 (Mo. Bot. Gard. Herb.).

Maine: Mt. Desert, 23 July, 1871, Boott (N. Y. Bot. Gard.
Herb.) ; Mt. Desert I., Somes Stream, 4 Sept., 1895, H. & C.
E. Faxon (Gray Herb.); Pushaw Pond, 21 August, 1899,
F. L. Harvey 3 (Mo. Bot. Gard. Herb.) ; Ripples Brook, un-
der water, Somesville, 1 August, 1892, Rand (Gray Herb.) ;
brook, north end of Dunning’s Pond, Somesville, 27 August,
1869, Boott (N. Y. Bot. Gard. Herb.) ; Ripple Brook, Somes-
ville, Mt. Desert I., 1 August, 1892, 3 October, 1893, Rand
(Mo. Bot. Gard. Herb.); Somes Stream, Mt. Desert I., 30
September, 1893, Rand (N. Y. Bot. Gard. Herb.); same
station, 4 September, 1895, Rand (Mo. Bot. Gard. Herb.) ;
west shore of Jordan’s Pond, Mt. Desert I., 3 September,
1892, Rand (Mo. Bot. Gard. Herb.); Small Pond, north
of Long Pond and Ripples Brook, and north end of Great
Pond, “Northwest Arm,” 22 September, 1892, Fernald (Gray
Herb.); brook, south end of Ripple Pond, Mt. Desert L.,
3 October, 1893, Rand (Mo. Bot. Gard. Herb. and N. Y.
Bot. Gard. Herb.); at dam, Ripples Pond, in gravel mud,
Mt. Desert I., 19 September, 1898, Rand (Mo. Bot. Gard.
Herb. and Gray Herb.); in brook, inlet of Ripples Pond,

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 197

19 September, 1898, Rand (Gray Herb.) ; in clay mud, south
end Great Pond, Mt. Desert I., 19 September, 1898, Rand
(Mo. Bot. Gard. Herb.); west shore of Jordan Pond, Mt.
Desert I., in sand under water, 3 September, 1892, Rand
(Mo. Bot. Gard. Herb.); pond north of Long Pond, Mt.
Desert I., 22 September, 1892, Fernald (Gray Herb.) ; Rip-
ples Pond, 22 September, 1892, Fernald (N. Y. Bot. Gard.
Herb.); rocky bed of Great Works River, North Berwick,
York Co., 25 September, 1897, Fernald (Gray Herb.) ; Bub-
ble Pond, Mt. Desert I., 11 September, 1895, Rand (Mo. Bot.
Gard. Herb.) ; same, 18 September, 1898, Rand (Mo. Bot.
Gard. Herb.); ledgy margin of Stillwater River, Orono, 4
September, 1893, Fernald y (Gray Herb. and N. Y. Bot.
Gard. Herb.); submersed, at end Eagle Lake, Mt. Desert
I., 20 September, 1900, Rand (Gray Herb.) ; Harrison, Cum-
berland Co., 31 July, 1919, Hames & Godfrey 9604 (Gray
Herb.) ; York, August, 1893, Thaxter (Gray Herb.) ; gravelly
margin of Pease River, East Wilton, 11 August, 1894, Fer-
nald (Gray Herb.); mill stream, Somesville, 10 July, 1893,
Rand & Redfield 3121 (Mo. Bot. Gard. Herb.).

New Hampshire: Echo Lake, N. Conway, 8 June, 1879,
Faxon (Mo. Bot. Gard. Herb. and Gray Herb.); sandy
bottom of ponds, Kingston, August, 1895, Haton (N.
Y. Bot. Gard. Herb.); country pond, Newton, 18 August,
1896, Haton 440 (Mo. Bot. Gard. Herb.); millpond,
Lamprey R., West Epping, 20 August, 1896, Eaton
(U. S. Nat. Herb. and Univ. Minn. Herb.); country
pond, Kingston, 5 August, 1896, Dodge (N. Y. Bot.
Gard. Herb.); bed of Lamprey R., Epping, 16 September,
1896, Eaton (Mo. Bot. Gard. Herb.) ; West Epping, 20 Aug-
ust, 1896, Haton 482C (Mo. Bot. Gard. Herb.) ; Gustin Pond,
Marlow, 29 July, 1899, Fernald 186 (in part) (Gray Herb.) ;
Pautuckaway Pond, Nottingham, Eaton 483B (Mo. Bot.
Gard. Herb. and N. Y. Bot. Gard. Herb.); same locality,
20 August, 1896, Eaton (Univ. Minn. Herb.); Epping, 12
August, 1896, Eaton 424, 431 (Mo. Bot. Gard. Herb.) ; Ep-
ping Corner, Eaton (Mo. Bot. Gard. Herb.); Gould Pond,
Greenfield, in about 3 ft. water, among yellow lilies, mud
over granite gravel, 24 July, 1906, Coville 2219 (Mo. Bot.
Gard. Herb. and U. 8. Nat. Herb.) ; country pond, Kingston,

[Vol. 9
198 ANNALS OF THE MISSOURI BOTANICAL GARDEN

September, 1895, Haton (Univ. Minn. Herb.); Lake Cho-
corua, 10 September, 1906, Farlow (Gray Herb.) ; Lamprey
River at Hedding, in about 10 in. water, 8 August, 1904,
Bragg (N. Y. Bot. Gard. Herb.).

Vermont: Grout Pond, Stratton, alt. 2225 ft., 6-10 August, 1900,
Eggleston 2200 (Mo. Bot. Gard. Herb., N. Y. Bot. Gard.
Herb., and Gray Herb.) ; South Pond, Marlboro, 15 Septem-
ber, 1895, Grout & Eggleston (N. Y. Bot. Gard. Herb.) ;
sandy shore of Kelly’s Bay, Alburgh, 31 August, 1893, Eg-
gleston (N. Y. Bot. Gard. Herb.); Lamprey R., Epping,
16 September, 1899, Haton (Univ. Minn. Herb.).

Massachusetts: in the Mystic, not the Pond, Medford, August,
1848, Tuckerman (Gray Herb.), Type; submersed at mar-
gin of winter pond, Winchester, 22 September, 1908, Fernald
(Gray Herb.); Arlington, 15 September, 1867, Boott (Gray
Herb.); Martin’s Pond, Reading, 24 August, 1869, Boott
(N. Y. Bot. Gard. Herb.); Pinkapog Pond, 27 August,
1867, Boott (N. Y. Bot. Gard. Herb.); submerged,
Worcester, Stone (N. Y. Bot. Gard. Herb.); Horn
Pond, south end, 16 September, 1869, Boott (N. Y.
Bot. Gard. Herb.); Kimball’s Pond, Amesbury, 15
August, 1899, Haton (Univ. Minn. Herb.); Mystic
Pond, 6 August, 1865, Boott (Mo. Bot. Gard. Herb.
and Gray Herb.); Mystic River near Boston, from
issue from Mystic Pond to Wood’s Dam, 21 October,
1866, Boott (Mo. Bot. Gard. Herb. and Gray Herb.) ; east
side of Mystic Pond, 14 July, 1867, Boott (Mo. Bot. Gard.
Herb. and Gray Herb.); north and west side of Mystic
Pond, 9 August, 28 October, 1867, Boott (Mo. Bot. Gard.
Herb. and Gray Herb.); north and east sides of Spy Pond,
Arlington, 5-8 September, 1867, Boott (Mo. Bot. Gard.
Herb. and Gray Herb.); Fresh Pond, north side, 3 Septem-
ber, 1868, Boott (Gray Herb.); entirely submerged, Spy
Pond, Arlington, August, 1878, Morong (Mo. Bot. Gard.
Herb., N. Y. Bot. Gard. Herb., and U. S. Nat. Herb.) ; Nut-
ting Pond, Billerica, 11 August, 1869, Boott (N. Y. Bot.
Gard. Herb.) ; entirely submerged, Horn Pond, 29 October,
1866, Boott (Mo. Bot. Gard. Herb. and Gray Herb.); Spy
Pond, Arlington, 8 August, 1881, Morong (N. Y. Bot. Gard.
Herb.); lower end of Horn Pond, 30 June, 1867, Boott

1922]

PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 199

(Gray Herb.); Horn Pond, 11 July, 16 September, 1867,
Boott (Mo. Bot. Gard. Herb. and Gray Herb.) ; Waushakum
Pond, So. Framingham, 29 June, 20 July, 1890, Sturtevant
(Mo. Bot. Gard. Herb.); sandy bottom, Lake Attitash,
Amesbury, August, September, 1895, Haton (Mo. Bot. Gard.
Herb., U. S. Nat. Herb., and Univ. Minn. Herb.); Quan-
naponit Lake, Wakefield, 10 September, 1869, Boott (N.
Y. Kot. Gard. Herb.) ; Attitash, Essex Co., Haton 960 (Mo.
Bot. Gard. Herb.); same, 27 June, 1896, Haton 197 ‘Mo.
Bot. Gard. Herb.); same, 31 July, 1896, Haton 382 (Mo.
Bot. Gard. Herb.) ; Chebacco Pond, Essex Co., 15 July, 1896,
Dodge (N. Y. Bot. Gard. Herb.) ; Chebacco Lake, Essex Co.,
August, 1896, Haton (Mo. Bot. Gard. Herb. and Univ. Minn.
Herb.); same, without date, Haton 378 (Mo. Bot. Gard.
Herb.); Chebacco Lake, Essex Co., 18 July, 1896, Dodge
(Gray Herb.); Bate’s Pond, Wenham, 29 July, 1896, Haton
3876 (Mo. Bot. Gard. Herb.); Nine-Mile Pond, Cape Cod,
4 September, 1898, Greenman 424 (Mo. Bot. Gard. Herb.) ;
Watson’s Pond, Taunton, 15 September, 1903, Eaton (Mo.
Bot. Gard. Herb.); Winneconnet Pond, Norton, 14 July,
1903, Eaton (Mo. Bot. Gard. Herb.) ; Merrimac River, New-
buryport, August, 1896, Dodge (N. Y. Bot. Gard. Herb.) ;
in fresh water, tidal shores Merrimac R., Newburyport, 1895,
Eaton (Mo. Bot. Gard. Herb.); Kimball’s Pond, Ames-
bury, July, 1896, and August, 1897, Haton (Mo.
Bot. Gard. Herb.); Kimball’s Pond, Amesbury, 27
June, 1896, Eaton (Univ. Minn. Herb.); Kimball’s
Pond, Essex Co., 13 August, 1899, Eaton (Mo. Bot.
Gard. Herb.); near Jerry’s Pond, West Tisbury,
Martha’s Vineyard, 24 August, 1916, Seymour 1017 (Gray
Herb.) ; Lake Cochichewick, North Andover, 24 September,
1903, Pease 2640 (Gray Herb.) ; submerged in shallow water,
sandy margin of Great Pond, Weymouth, Norfolk Co., 2
September, 1918, Churchill (Mo. Bot. Gard. Herb.) ; car-
peting the sandy bottom of Spectacle Pond, Wellfleet, Barn-
stable Co., 19 September, 1918, Fernald & Weatherby 15950
(Gray Herb. and Mo. Bot. Gard. Herb.); sandy bottom,
Great Pond, Weymouth, 2 September, 1918, Knowlton (Mo.
Bot. Gard. Herb. and Gray Herb.); Buck Pond, Harwich,
wet sandy lower beach and inundated margin, 30 August,

[Vol. 9
200 ANNALS OF THE MISSOURI BOTANICAL GARDEN

1918, Fernald & Long 15949 (Gray Herb. and Mo. Bot.
Gard. Herb.).

Connecticut: muddy border of pond, Niantic, East Lyme, 19
August, 1913, Bissell (Gray Herb.) ; submerged, stony shore,
lower end of Long Pond, Ledyard, 4 August, 1896, Graves
189 & 140 (Mo. Bot. Gard. Herb.); same place and date,
Graves (Gray Herb.); in mud, bare at low water, head of
Hamburg Cove, Lyme, 10 September, 1902, Graves (Mo.
Bot. Gard. Herb.).

A.A.

56. I. foveolata Eaton in Dodge, Ferns and Fern Allies of N.
Eng. 38. 1896.

Corm 2-lobed, rarely 3; leaves 20-45, 8-18 cm. long, rather
slender, round, becoming dark green; stomata few, near tips
of leaves; peripheral strands none; ligule short triangular; spo-
rangia 4-7 mm. long, brown-spotted, with very narrow velum;
megaspores white, 360-560 u, rarely 600, in diameter, dense-
ly sculptured with somewhat irregular reticulations formed
by wide, high ridges surrounding deep pits; microspores 23-33 py
long, minutely papillose.

Distribution: New Hampshire.

Specimens examined:

New Hampshire: pond on Lamprey River, Epping, 20 August,
1896, Eaton (Mo. Bot. Gard. Herb. and Gray Herb.), TyPE;
West Epping, 20 August, 1896, Haton 482A (Mo. Bot. Gard.
Herb. and Gray Herb.); Epping Corner, 14 September,
1899, Eaton 299 (Mo. Bot. Gard. Herb.); New Market,
Eaton (Mo. Bot. Gard. Herb.) ; Epping, Pautuckaway River,
Eaton 432 (Mo. Bot. Gard. Herb.); Lamprey River, Ep-
ping, August, 1897, Eaton (Mo. Bot. Gard. Herb.).

57. I. Martii A. Br. Kuhn in Martius, Fl. Brasil. 17: 646. pl. 78.
1884; Baker, Fern Allies, 129. 1887.

Corm 2-lobed, small; leaves 24-52, up to 75 cm. in length,
soft green, flexuous, reddish brown at base, with membranaceous
margins extending 6-8 cm. above sporangium level; stomata
near tips of leaves, lacking below; peripheral strands usually
lacking or weak; ligule cordate-triangular; sporangium 6-8 mm.
long, partly covered by velum (1/2-2/3); megaspores chalky
white, 580-660 » in diameter, marked with irregular, confluent,

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 201

high, blade-like ridges, extending away from commissural ridges

on upper faces, somewhat incompletely reticulate above, irreg-

ularly reticulate basally; microspores fawn-colored, 30-35 u long,
smooth.

Distribution: Brazil.

Specimens examined:

Brazil: Prov. Minas Geraés, 22 January, 1874, 18 December,
1864, Regnell ser. III 1506 (Gray Herb. and U. S. Nat.
Herb.), Type; Serra do Itatiaia, “ in rivulo,” 29 June, 1902,
Dusen 643 (U.S. Nat. Herb.).

58. I. Engelmanni A. Br. Flora 29. 178. 1846; Baker, Jour.
Bot. 18: 105. 1880; Motel. & Vendr. Actes Linn. Soc. Bord. 36:
374. pl. 12. fig. 1-9. 1883; Gray, Manual, ed. 4, 606. 1869; Clute,
Fern Allies, 233. 1905.

I. Engelmanni var. gracilis Engelm. in Gray, Manual, ed. 5,
ori. “LS6T.

I. Engelmanni var. fontana Eaton, Fern Bull. 13: 52. 1905.

I. Engelmanni var. valida Engelm. in Gray, Manual, ed. 5,
677. 1867.

I. valida Clute, Fern Allies, 236, 260. 1905.

Corm 2-lobed; leaves 15-60 (100), 18-50 cm. long, light green;
stomata numerous; peripheral strands variable in number or
none; sporangia oblong, unspotted, with narrow velum; mega-
spores white, 400-570 (615) » in diameter, distinctly marked
with honeycomb network of narrow ridges; microspores 21-30 u,
seldom 33 u, in length, smooth to minutely roughened.

Distribution: eastern border to Mississippi Valley.

Specimens examined:

New Hampshire: “In a slight brooklet, dry most of the summer,”
in a forest, Seabrook, July, 1895, Haton (Mo. Bot. Gard.
Herb.) ; millpond, in clay, Hampton Falls, August, 1895,
Eaton (Mo. Bot. Gard. Herb.) ; Coffin’s Mill, 16 July, 1896,
Eaton (Mo. Bot. Gard. Herb.); mill-pond, Hampton
Falls, 1 August, 1896, Eaton (Mo. Bot. Gard. Herb.) ;
Powow River, South Hampton, 18 August, 1896,
Eaton 439 (Mo. Bot. Gard. Herb.); Trickling Falls,
1896, Haton (Mo. Bot. Gard. Herb.); East King-
ston, 28 July, 1896, Eaton 363-364 (Mo. Bot. Gard. Herb.) ;
flats at East Kingston, 6 July, 1896, Eaton 231 (Mo.

202

[Vol. 9
ANNALS OF THE MISSOURI BOTANICAL GARDEN

Bot. Gard. Herb.); flats at Trickling Falls, Kingston,
August, 1897, Haton (Mo. Bot. Gard. Herb.) ; Dodge’s Pond,
Hampton Falls, Haton (Mo. Bot. Gard. Herb.) ; Horse Hill,
Kensington, 19 April, 1896, Haton 1 (Mo. Bot. Gard.
Herb.) ; Lamprey River, Epping, August, 1897, Haton (Mo.
Bot. Gard. Herb.) ; Stratham, 1899, Haton (Mo. Bot. Gard.
Herb.).

Vermont: in Clark’s Pond, near Brattleborough, “ in spring sub-

merged, in fall on dry banks,” 1867, JZJann (Mo. Bot. Gard.
Herb.); Brattleborough, 1867, Frost 18 (Gray Herb.); in
shallow water on muddy bottom, Little Pond, Orwell, 8
August, 1915, Hames & Godfrey 9204a (Gray Herb.).

Massachusetts: Woburn Brook, 16 November, 1862, Boott (Mo.

Bot. Gard. Herb.) ; millpond stream in West Cambridge, 26
October & 5 November, 1865, Boott (Mo. Bot. Gard. Herb.) ;
West Cambridge, entirely out of water, 26 October, 1865,
Boott (Gray Herb.); West Cambridge Brook, entirely sub-
merged (5 miles northwest from Boston), 29 October, 1866,
Boott (Mo. Bot. Gard. Herb.) ; Arlington Brook, 28 October,
1867, Boott (Mo. Bot. Gard. Herb.); Arlington Brook, 12
September, 1867, Boott (Mo. Bot. Gard. Herb.); Arling-
ton Brook, 7 August, 1870, Boott (Gray Herb.); South
Natick, 25 June, 1879, Morong (Mo. Bot. Gard. Herb. and
Gray Herb.); in water and mud along margin where pond
has dried away, Blacksmith Pond, Needham, 19 July, 1885,
Fuller (Gray Herb.) ; near dam, Waverley, November, 1894,
Duggar (Gray Herb.); mill-pond, Waverley, October, 1894,
Seymour (Gray Herb.) ; Newburyport, 22 June, 1894, Dodge
(Mo. Bot. Gard. Herb.) ; West Newbury, July, 1896, Dodge
(Mo. Bot. Gard. Herb.) ; Tuxbury’s Pond, Eaton (Mo. Bot.
Gard. Herb.); Waverley, 11 October, 1894, Blankinship
(Mo. Bot. Gard. Herb.); Blue Hills Reservation, Metro-
politan Park System, 2 September, 1895, Jenks (Mo. Bot.
Gard. Herb.); Pine Tree Pool, Blue Hills Reservation, 2
September, 1895, Williams (Gray Herb.); in brook, Blue
Hills, Quincey, 5 September, 1895, Fernald (Gray Herb.) ;
Shaker Glen, Woburn, 1 September, 1895, Williams (Gray
Herb.); Race Course Pond, Billingham, 24 August, 1894,
EH. & C. E. Faxon (Gray Herb.); Nashawena Island, Buz-
zards Bay, C. E. Faxon 7 (Mo. Bot. Gard. Herb. and Gray

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 2038

Herb.); in shallow water, Blue Hills Reservation, West
Quincy, 2 September, 1895, Rich (Gray Herb.) ; pool, heart
of Pine-Tree Brock, Blue Hills Reservation, Milton, 2 Sep-
tember, 1895, Churchill (Gray Herb.).

Rhode Island: Newport, July, 1878, C. H. Faxon 5 (Mo. Bot.
Gard. Herb. and Gray Herb.) ; near Newport, in deep water,
1866, Durand (Mo. Bot. Gard. Herb.); shallow pool, New-
port, 1878, Farlow (Mo. Bot. Gard. Herb,); (Wordens
Pond) “Lake Werden,” So. Kingston, 24 August, 1881,
E. & C. E. Faxon (Gray Herb.); Newport, Thurber (Gray
Herb.).

Connecticut: fresh water, tidal shores, New Haven, 1857, D. C.
Eaton 1 (Mo. Bot. Gard. Herb.) ; without date, New Haven,
D. C. Eaton (Gray Herb.); shallow mountain stream on
gravelly bottom, Colebrooks, 10 September, 1864, Robbins
13 (Mo. Bot. Gard. Herb.) ; edge of little pond in Meriden,

-pond south of West Peak, 10 October, 1873, Hall (Mo. Bot.
Gard. Herb.); Bristol, 1888, Bishop (U. 8. Nat. Herb.) ;
Hart’s Upper Reservoir, Berlin, 27 September, 1900, Bishop
(Gray Herb.); shallow water, Eight-Mile River “at rail-
road,” Southington, 3 August, 1902, Bissell (Mo. Bot. Gard.
Herb.) ; submerged in shallow water of Mill River, Easton,
29 August, 1897, Eames (Gray Herb.); shallow water of
pond, in mud, Stafford, 28 August, 1903, Bissell (Mo. Bot.
Gard. Herb.); pond at Stafford St., Stafford, 28 August,
1903, Bissell (Gray Herb.); Bantam Lake, July, 1891, Un-
derwood (Gray Herb.); Rainbow Park, Windsor, 30 August,
1907, Eaton (Mo. Bot. Gard. Herb.) ; Selden’s Cove, Lyme,
28 August, 1907, Haton (Mo. Bot. Gard. Herb.) ; “Curtis’
Mill-Pond,’ Stepney, 11 September, 1897, Hames (Gray
Herb.); pond at icehouse, Norwalk, 16 September, 1901,
Bissell (Gray Herb.); in shallow water, Waterbury, 7 July,
1908, Blewitt (Gray Herb.); New Britain, 22 June, 1913,
Lunt (Gray Herb.); small pond at foot of West Peak, Me-
riden, 25 September, 1910, Bissell (Gray Herb.); wet bank
of pond, Gaylordsville, 29 August, 1904, Hames (Gray
Herb.); Miamus River, Stamford, 5 July, 1909, Hames &
Godfrey 8223 (Gray Herb.); abundant in Bunnell’s Pond,
in 1-3 ft. water, Bridgeport, 5 August, 1913, Hames (Gray
Herb.) ; in half-shade, shallow water of pond, southeastern

[Vol. 9
204 ANNALS OF THE MISSOURI BOTANICAL GARDEN

part of town of Sterling, 12 August, 1914, Bissell (Gray
Herb.).

New York: high water mark, muddy shores just above Peeks-
kill, 19 August and 3 September, 1869, Leggett? (Gray
Herb.) ; Peekskill, Hudson River, high water mark, 3 Sep-
tember, 1869, Leggett (Mo. Bot. Gard. Herb.) ; Locke Pond,
Central New York, 21 July, 1881, Dudley (Mo. Bot. Gard.
Herb.) ; marl ponds, South Cortland, 29 June, 1884, Dudley
(Mo. Bot. Gard. Herb.) ; east side, Cayuta Lake, in sand,
21 June, 1885, Dudley A (Mo. Bot. Gard. Herb.) ; marl pond
near South Cortland, 3 August, 1886, Dudley (Mo. Bot.
Gard. Herb.); near Norwich, Chenango Co., 21 August,
1888, Fitch (Mo. Bot. Gard. Herb.); near Ithaca, 1898,
Overacker (Mo. Bot. Gard. Herb.) ; Ithaca, July, 1898, Ashe
(Mo. Bot. Gard. Herb.); Mt. Verrion, 28 October, 1900,
Clute (Mo. Bot. Gard. Herb.); brook at East Chester, 28
October, 1900, Buchheister (Mo. Bot. Gard. Herb.) ; pond,
McLean, 19 July, 1916, Munz 479 (Pomona Coll. Herb.) ;
muddy border of Isoetes Pond, South Cortland, 18 July,
1915, Faull 3430 (Gray Herb.); in 3 ft. of water near south
end of Lake Ronkonkoma, Suffolk Co., 5 July, 1908, Harper
88 (Gray Herb.) ; mudhole southwest of Chicago bog, Cort-
land, 22 July, 1916, McDaniels 5446 (Mo. Bot. Gard.
Herb.); Sparta, 16 August, 1907, von Schrenk 252 (Mo.
Bot. Gard. Herb.) ; in dried pond, Chicago Station, Ithaca,
6 August, 1921, Drushel 4664 (Mo. Bot. Gard. Herb.).

New Jersey: near Camden, opposite Philadelphia, September,
1863, Durand (Mo. Bot. Gard. Herb.); “mud and spring
water’, 5144 miles from Philadelphia in N. J., 1 October,
1865, Smith (Mo. Bot. Gard. Herb.); im a ditch on the
Atlantic City Railroad, 4 miles from Camden, 1866, Durand
(Mo. Bot. Gard. Herb.); pool 344 miles from Camden, on
railroad to Atlantic City, end of October, 1867, Durand (Mo.
Bot. Gard. Herb.) ; Closter, 1859, Austin 3 (Mo. Bot. Gard.
Herb.) ; bottom of Hackensack River, without date, Austin
(U. S. Nat. Herb.); submerged, sandy bottom, Panther
Pond, Sussex Co., 18 September, 1904, Mackenzie 1059 (Mo.
Bot. Gard. Herb.).

Pennsylvania: West Chester, 1839, McMinn (U.S. Nat. Herb.) ;
Lancaster Co., Porter (Gray Herb.); swamp at Smithville

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 205

near Lancaster, in soft mud, half immersed, 1 October, 1866,
Porter (Mo. Bot. Gard. Herb.); in small ditches, not near
tide-water, near Darby, Philadelphia, 4 July, 1866, Hunt
(Mo. Bot. Gard. Herb.) ; Delaware Water Gap, June—July,
1870, Knipe (Mo. Bot. Gard. Herb.); mountain swamp, 2
miles southwest of Cornwall, Lebanon Co., 1 August, 1878,
Porter (Mo. Bot. Gard. Herb.) ; wholly immersed in a lake
at Delaware Water Gap, August, 1880, Canby (Mo. Bot.
Gard. Herb.); Delaware River, at Monroe, Buck Co., 24
July, 1886, J. A. & H. F. Ruth (Univ. Minn. Herb.) ; Mon-
roe Co., 26 July, 1886, Porter (Dudley Herb.); McCall’s
Ferry, 2 miles south of Bethesda, July, 1898, Galen (Mo.
Bot. Gard. Herb.); Susquehanna River, Wayne Co., 20
July, 1900, Clute (Mo. Bot. Gard. Herb.) ; pool among rocks,
York Co., 2-6 July, 1904, Britton (Mo. Bot. Gard. Herb. and
N. Y. Bot. Gard. Herb.) ; Sayre, edge of river, August, Bar-
bour (Mo. Bot. Gard. Herb.) ; Delaware Water Gap, 3 July,
1887, Britton (Gray Herb.); vicinity of McCall’s Ferry,
York Co., 5-7 July, 1904, Rose & Painter 8168, 8216 (U.S.
Nat. Herb.) ; in soft mud of a partially exsiccated pond, near
Warriorsmark, Huntingdon Co., at foot of Alleghenies, 20
August, 1868, Porter (Mo. Bot. Gard. Herb. and Gray
Herb.) ; in clay mud and water of a pond in the barrens of
Huntingdon Co., 1200 ft. above sea-level, September, 1870,
Porter (Mo. Bot. Gard. Herb. and Gray Herb.) ; Smithville,
Lancaster Co., August, 1865, Porter (Mo. Bot. Gard. Herb.) ;
same, 1 October, 1866, (Mo. Bot. Gard. Herb.) ; pond near
Warriorsmark, October, 1870, Davis (Mo. Bot. Gard. Herb.).
Delaware: Wilmington, 1860, Tatnall (Gray Herb.); in a bog
near Wilmington, 1858, Tatnall (Gray Herb.); Wilming-
ton, 16 June & 23 July, 1866, Canby (Mo. Bot. Gard. Herb.
and Gray Herb.); in a ditch near Ogletown (dry at time
of collection), 4 August, 1866, Commons (Mo. Bot. Gard.
Herb.); ponds, Townsend, 4 July, 1896, Canby (Mo. Bot.
Gard. Herb.) ; in small ditch along Baltimore River, 14 mile
below Stanton Station south of Wilmington, 21 September,
1866, Canby (Mo. Bot. Gard. Herb.); same, August, 1867,
(Mo. Bot. Gard. Herb.); Wilmington, 1865, Durand (Mo.
Bot. Gard. Herb.) ; Wilmington, 25 September, 1866, Canby
(Mo. Bot. Gard. Herb. and Gray Herb.) ; Wilmington, ditch-

(Vol. 9
206 ANNALS OF THE MISSOURI BOTANICAL GARDEN

es near Baltimore R. R., 16 June, 1866, Canby (Mo. Bot.
Gard. Herb.) ; Wilmington, 23 July, 1866, Canby (Mo. Bot.
Gard. Herb.) ; same, 21 September, 1866, & 12 June, 1867,
Canby (Mo. Bot. Gard. Herb. and Gray Herb.) ; Wilming-
ton, 2 October, 1866, Canby (Gray Herb.); ditches near
Stanton, August, 1867, Canby (Mo. Bot. Gard. Herb.) ;
Delaware, June, 1872, Canby (Gray Herb.) ; Stanton, June,
1872, Canby (Gray Herb.); near Wilmington, Canby 1957
(Mo. Bot. Gard. Herb.).

Maryland: near Great Falls of the Potomac, 11 June, 1882,
Ward (Mo. Bot. Gard. Herb.).

Virginia: head of Mountain Lake, Salt Pond Mt., alt. 4000
ft., August, 1889, Canby (Mo. Bot. Gard. Herb.) ; swampy
soil near Mountain Lake, Salt Pond Mt., August, 1869,
Canby (Gray Herb.).

North Carolina: in standing water, Swain Co., 10 August, 1891,
Beardslee & Kofoid (Mo. Bot. Gard. Herb. and Gray
Herb.) ; near Hendersonville, May, 1919, Thomas (Mo. Bot.
Gard. Herb.); in bogs formed by cold springs on Spring
Mts. (near Columbus), Polk Co., elev. about 3000 ft., 5
May, 1897, Biltmore Herb. 55641 (Gray Herb.).

South Carolina: springy places near Graniteville, Aiken Co.,
19 May, 1899, Eggert (Mo. Bot. Gard. Herb.) ; same station,
24 & 25 May, Eggert (Mo. Bot. Gard. Herb.).

Georgia: mountains of Georgia, 1872, Chapman (N. Y. Bot.
Gard. Herb.) ; mountain streams of Georgia, 1873, Chapman
(Mo. Bot. Gard. Herb.); Floy Co., Chapman (Mo. Bot.
Gard. Herb.) ; wet shady woods at eastern base of Taylor’s
Ridge, Whitfield Co., 26 July, 1900, Harper 310 (Mo. Bot.
Gard. Herb., N. Y. Bot. Gard. Herb., and Gray Herb.).

Indiana: in a small pond, 8.7 miles southeast of Paoli, on Paoli
and New Albany Pike, 16 October, 1917, Deam 24360 (Mo.
Bot. Gard. Herb.) ; in small pond on north side of road and
about 1 mi. east of Pilot Knob, Crawford Co., 12 October,
1916, Deam 22385 (Gray Herb.) ; low place in woods, where
in wet seasons the water would course through woods, 4 mi. ~
south and 1 mi. east of Palmyra, Harrison Co., Deam 20467
(Gray Herb.).

Illinois: Ponds, St. Clair Co., Eggert (Mo. Bot. Gard. Herb.).

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 207

Missouri: ponds in the Meramec Hills, southwest of St. Louis
(Gravois Settlement), September, 1842, Engelmann (Mo.
Bot. Gard. Herb. and Gray Herb.), Typz; St. Louis, Sep-
tember, 1842, Engelmann (U.S. Nat. Herb.).

58a. Var. caroliniana Eaton, Fern Bull. 8: 60. 1900.

Corm 2-lobed; leaves 15-25(30), up to 22 em. long, little
finer than J. Engelmanni (much like I. Dodgei); peripheral
strands 4, weak; stomata numerous; sporangium 6-8 mm. long,
1/3-2/3 covered by velum; megaspores 400-530 1 in diameter,
with high reticulate ridges, much crisped and cut with an ir-
regular margin, producing somewha¥ spiny effect; microspores
24-34 » long, spinulose.

Distribution: North Carolina, Georgia.

Specimens examined:

North Carolina: Big Rock Creek, Mitchell Co., 1893, Ashe 1092
(Mo. Bot. Gard. Herb.), Typz; growing partly immersed,
Wetherby’s near Salisbury, Mitchell Co., Ashe 812 (Mo.
Bot. Gard. Herb.) ; Roandale Farm, 28 July, 1900, Wether-
by (Mo. Bot. Gard. Herb.) ; edge of fish-pond, gravelly bot-
tom, half submerged or less, Wetherby’s, 15 August, 1898,
Wetherby (Mo. Bot. Gard. Herb.).

Georgia: muddy swamp of Turkey Creek, about 6 mi. south of
Dublin, Laurens Co., 21 April, 1904, Harper 2142 (U.S. Nat.
Herb.) ; in sluggish pine-barren stream, Sumter Co., partly
emersed, 24 July, 1901, Harper 1112 (Mo. Bot. Gard. Herb.
and U. S. Nat. Herb.).

59. I. azorica Dur. Milde, Fil. Eur. 278. 1867; Baker, Jour.
Bot. 18: 67. 1880, and Fern Allies, 125. 1887; Motel. & Vendr.
Actes Soc. Linn. Bord. 36: 365. pl. 8. fig. 9, 10, 11. 1883; Trelease,
Mo. Bot. Gard. Ann. Rept. 8: 176 . 1897.

Calamaria azorica Kuntze, Rev. Gen. Pl. 2: 828. 1891-93.

Corm 2-lobed; leaves 7-25, 8-30 em. long, slender, flexuous,
with narrow basal membranaceous margin; stomata present, but
not numerous; peripheral strands none; ligule long subulate;
sporangia oval, 4-6 mm. long, 1/3-1/2 covered by velum; mega-
spores 360-490 up in diameter, white, reticulate with narrow low
distinct crests, mostly rounded, seldom sharp; microspores

{Vol. 9
208 ANNALS OF THE MISSOURI BOTANICAL GARDEN

brown, 26-37 u in length, chiefly spinulose, sometimes smoothish.
Distribution: Islands of Azores.
Specimens examined:

Azores: Lago Raza, 4 August, 1894, Trelease 1262 (Mo. Bot.
Gard. Herb.) ; Corvo Caldeiro, 15 July, 1894, Trelease 1261
(Mo. Bot. Gard. Herb. and U. S. Nat. Herb.); Flores L,
Caldeiro da Lomba, 25 July, 1894, Trelease 1263 (Gray
Herb., Mo. Bot. Gard. Herb. and U. 8S. Nat. Herb.).

60. I. japonica A. Br. Verh. Bot. Ver. Brandenb. 4: 329. 1862,
and Monatsber. K. Akad. Wiss. Berlin 1: 459. 1861; Motel. &
Vendr. Actes Soc. Linn. Bord. 36: 360. pl. 11. fig. 10-12. 1883;
Baker, Jour. Bot. 18: 109. 1880, and Fern Allies, 133. 1887;
Miquel, Prol. Fl. Jap. 390. 1866-67; Franchet & Sav. Enum.
Pl. Jap. 2: 201. 1879.

Calamaria japonica Kuntze, Rev. Gen. Pl. 2: 828. 1891-95.

I. edulis Lieb. ex Miq. Prol. Fl. Jap. 390. 1866-67.

Corm 3-lobed; leaves 35-66, 33-52 cm. long, medium coarse,
flexuous, gradually tapering to apex, with membranaceous mar-
gin conspicuous only at sporangium level; peripheral strands
usually 6, 4 of which are stronger; stomata rare; ligule elongated
triangular; sporangia 7-9 mm. long, lacking velum, but marked
with brown sclerenchyma patches; megaspores white, 560-660 uy
in diameter, with large foveolate markings, slightly less regular
on apical faces, with well-rounded ridges on basal; microspores
pale, 29-35 » long, smooth.

Distribution: Japan, Yokohama.

Specimens examined:

Japan: Wada-mura, Musashi, 6 September, 1893 (U. S. Nat.
Herb.) ; Tokyo, May, 1888, collector unknown, 519 (U.S.
Nat. Herb.) ; 30 July, 1890, Watanabe (Gray Herb.).

61. I. Wormaldii Sim, Trans. S. Afr. Phil. Soc. 16%: 299. pl. 5.
1906, and Ferns of S. Afr. 340. 1915.

Corm 3-lobed; leaves 50-70 in number, terete or somewhat
flattened, 22-45 em. long, stout, hardly narrowed to the round-
ed point, flaccid, with wide basal sheath briefly extended (2-3
cm.); peripheral strands none; stomata present though not
numerous; sporangium large, 5-10 mm. long, 3-3.5 mm. wide,
lacking a velum; megaspores} 460-640 » in diameter, with sur-
face decidedly reticulate with prominent rounded ridges on lower

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 209

surface, sometimes little sharper above; microspores 28-35 yp in
length, tuberculate.

Distribution: East London, 8S. Africa.

Specimens examined:

South Africa: East London, Lake Province, Union of 8. Africa,
November, 1921, Schonland (Mo. Bot. Gard. Herb.).

In the description published by Sim, mention is made of peri-
pheral strands as being “one marginal on each side throughout.”
The material at hand in the single collection examined did not
show peripheral strands in any sections cut. In all the leaves
the basal portion was the chief region available, though some of
the narrower part was cut in a few sections. It may be that with
exposure near the water surface there is some development of
supporting tissue not witnessed in Schonland’s collection.

62. I. Duriaei Bory, Compt. Rend. Acad. Paris 18: 1166. 1844.
I. tridentata Dur. ace. Kuhn, Fil. Afr. 195. 1867.

I. ligustica de Not. ace. Kuhn, Fil. Afr. 195. 1867.

Tsoetella Duriaei Genn. Comment. Critt. Ital. (1) no. 2: 115.

1861.

Calamaria Duriaei Kuntze, Rev. Gen. Pl. 2: 828. 1891-93.
Corm 3-lobed; leaves 15-35, 8-12 cm. long, rarely longer,
slender, firm, recurved, with short wide membranaceous margins

at base; bases of leaves persistent, scaly, shining black, with 3

teeth; stomata numerous; peripheral strands 4; sporangia oval,

4-6 mm. long, with complete velum; megaspores white, 600-

830 u in diameter, with prominent commissural ridges, and faces

with reticulate markings produced by even, rounded elevations;

microspores 26-38 u in length, tuberculate.
Distribution: Algeria, Corsica, France, Italy, Turkey.
Specimens examined:

Algeria: Algeria, 1841, Durieu (Mo. Bot. Gard. Herb.); Be-
bazoun near Algiers, March, 1844, Duriew (Mo. Bot. Gard.
Herb.); dry sandy plateaus of Mastapha near Algiers, 7
June, 1863, Durieu (Mo. Bot. Gard. Herb.).

Sicily: Pantelleria, Favare, April, 1890, Rose (N. Y. Bot. Gard.
Herb.) ; in wet fields, Messina, June, 1907, Ross 800 (Gray
Herb.).

Corsica: pastures, Bastia, 15 March, 1865, Debeaux (Mo. Bot.
Gard. Herb.); in swampy places, near Bastia, Corsica,

[Vol. 9
210 ANNALS OF THE MISSOURI BOTANICAL GARDEN

March, 1869, Gandoger (Mo. Bot. Gard. Herb.) ; wet grass-
lands at edge of water, at “Griggione,” near Bastia, 25 April,
1869, Fl. Exsicc. Billot 2290 (Mo. Bot. Gard. Herb.) ; Erisa,
March, 1885, Reverchon (Mo. Bot. Gard. Herb.).

France: Plateau de Roquehaute (Hérault), 3-5 June, 1862,
Durieu (Gray Herb.) ; Roquehaute near Béziers (Hérault),
3 June, 1862, Cosson (Mo. Bot. Gard. Herb. and Gray
Herb.) ; Roquehaute near Béziers, 5 May, 1866, Herb. Grand
Marais (Mo. Bot. Gard. Herb.); Portiragnes (Hérault), 30
March, 1890, Neyraut (Mo. Bot. Gard. Herb.); Hérault,
1870 (?), Durieu (Gray Herb.) ; sandy clearings of pine be-.
tween Cannes and Antibes, 1861, Bourgeau, Pl. Alpes mari-
times, (Gay) 361 (Gray Herb.) ; near Cannes, 13 June, 1861,
Bourgeau 2 (Gray Herb.); “bois de la Moure prés Mont-
pellier”, 8 May, 1870, Duval-Jouve (Gray Herb.) ; Antibes,
November, 1863, Kay (Gray Herb.); wet sandy stretches
under the pines, Golfe Jouan, near Antibes, Shuttleworth
(Gray Herb.).

Italy: Asciano, Prov. Pisa, Tuscany, alt. 12 m., calcareous soil,
14 April, 1906, Barsali 401 (Gray Herb.); province Pisa,
April, 1862, Ball (Gray Herb.).

Turkey: Rizeh, Lazistan, arid land at base of Falaises, 10 June,
1866, Balansa 1560 (Gray Herb.).

Sardinia: St. Barbara near Cagliari, 19 May, 1863, Ascherson &

Reinhardt (Gray Herb.).

LITTLE-KNOWN FORMS

63. I. natalensis Baker, Handbook Fern Allies, 132. . 1887.
Sim, Ferns S. Afr. 340. 1915.

“Rootstock 3-lobed; leaves 12-16, very slender (14 lin. diam.),
pale green, opaque, firm in texture, 2-3 inches long, rounded on
the back, channeled down the face, furnished with stomata and
accessory bast-bundles. Sporange small, globose, brownish;
veil none. Macrospores white, with small tubercles between
the ribs and large ones over the remainder of the surface. Micro-
spores granulated.”

Distribution: “Natal; Griffin’s Hill, Eastcourt, Rehmann.
7296.”

1922]
PFEIFFER—-MONOGRAPH OF THE ISOETACEAE

211

Specimens examined:

Africa: Cape of Good Hope, Lehman feu Herb. and Mo. Bot.
Gard. Herb.).

Gray Herb. collections shows megaspores 570-600 p in diam-
eter, minutely roughened on the three upper faces, and on the
fourth, showing short serpentine ridges. The vegetative charac-
ters coincide well with Baker’s form; the number of leaves is 11,
they are fine and long (31-82 cm.), and bear oblong sporangia
(3-5 mm. long), with no velum.

It seems as if Rehmann might conceivably be a misprint of
Lehman.

Mo. Bot. Gard. Herb. specimen has 10 very slender leaves,
30-85 cm. long, with fairly prominent basal sheath; spores of
same character as above but as low as 480 »; velum very narrow.

64.1. neoguineensis Baker in Sadebeck, Engl. and Prantl, Nat.
Pflanzenfam. 1*: 776. 1901.

Placed with J. Mulleri A. Br. and IJ. Kirkw A. Br., under divi-
sion with indusium complete, with more or less numerous sto-
mata; megaspores gray or light gray, warty.

List oF EXSsICccATAE CITED

The distribution numbers are printed in italic. Collections
distributed without numbers are indicated by a dash. The num-

bers in parentheses indicate the species numbers in the present
revision.

Allard — (51).

Allen — (42); — (50); — (55).

Anderssen — (40).

Andrews — (48a).

Archer — (28).

Areschoug — (51).

Arrhenius — (40).

Arthur, Bailey, Holway B413, B87 (42).

Arsene 3658 (37).

Ashe 1092, 812, — (58a).

Ascherson — (7); — (16); — (51);
— (62).

Ascherson & Reinhardt — (16); —
(25a); — (62).

Austin 3 (58).

Balansa 1560 (62);

1827 (25a); 849
(25) —~ (10).

Balfour — (51).

Ball — (25); — (62).
Ballard — (6).

Barber 394 (42).

Barbour — (58).

Bardell — (50).

Barsali 401 (62).

Battey — (42).

Beardslee & Kofoid — (58).
Bergesen — cel)
Bessey 1 (52); 2
Best — (48a).
Best & Crawford — (48a).

(35).

Billot — (51); 2290 (62).
Biltmore Herb. 4264, 4264b (29);
55641 (58).

Bishop — (42); — (58); — (42a).

212

Bissell — (42); — (55); — (58); —
(42a); — (48).

Blanchard — (42),

Blankinship — (58).

Blasdale — (26).

Blewitt — (58).

Blomberg — (40).

Blytt 1951 (40); 1958 (51).

Bolander — , 5093, 5091, 5080 (35);
6025, 6383 (35a).

Boldt 17, 418 (51).

Boott — (42); — ,11 (54); — (55);
— (58).

Boreau — (12).

Bory —(25); — (10); — (15a).

Bourlier — (15).

Bourgeau — 2, 361 (62).

Bragg — (55).

Brainerd — (42).

Brand — (51).

Brandegee — (26); — (34);
(34a); — (27); — , 2001 (35).

Braun — (40); — (51).

Bristol — (42).

Britton, Dr. & Mrs. — (42).

Britton — (42); — (46); — (54); —
(58).

Brown — (42).

Bubani — (6).

Buchenau — (51).

Buchheister — (58).

Budden — (51).

674

Burbank, Grout & Eggleston — (42).

Burtt Davy — (27).

Bush — ,441, 746, 267, 35, 107,
1581, (38); 1580, 107, 231, 68, 7547,
2917, 4511 (39).

Butler — (38); — ,24 (39).

Butter — (51).

Canby — (29); 186 (39); — (42); —
(47) 5 —9 (48) 5. 1957, — (58).

Carnel — (25).

Celakovsky 1503 (51).

Cesati — (7); — (40).

Chaboisseau 395, 70 (12).

Chamberlain — (42).

Chapman — (31); — (42); — (58).

Chase 86, 136 (38).

Cheeseman — ,56 (17); — (18).

Cheveneau — (6).

Chickering 7 (48).

Chiovenda — (40).

Christ — (40); — (51).

Churchill — (42); — (55); — (58).

Clauson 99, 99bis (15).

Clemens 1, 2 (35).

Clements, R. E. & E. 8. 493.1 (42).

Clinton — (42).

Clokey 3986 (35).

Clute — (42); — (58).

Collins — (42).

[Vol. 9

ANNALS OF THE MISSOURI BOTANICAL GARDEN

Commons — (48); — (58); — (47).

Congdon 91 (34); 991 (35).

Cooper 26 (54).

Copeland 2281 (34).

Cosson — (6); — (15); — (l6da);
—_ (15b); — (25); — (40); —
(51); — (62).

Coville 2483, 1058 (35); 84 (42); 123
(47); 88, 78, (54); 62 (54a); 2219
(55).

Coville & Funston 1722, 1643, 1650,
1691 (35).

Coville & Kearney 2336,
(48).

Coville & Leiberg 271 (35).

Cowles 776 (42).

Cowles & Harvey 2 (42); — ,1 (54).

Croall —, 1418 (51).

Curran — (34); — (26); — (27); —
(35); — (52).

Curtiss 3818 (31); 3813, 6696 (31a).

Cusick 1451 (35).

Darlington — (42).

Davenport — (42).

Davis — (42); — (58).

Deam 24360, 20467, 22385 (58).

de Bary —(40).

Debeaux — (15); — (15a); — (25);
i (62),

de Gerard — (6).

de la Perraudiere — (6).

23837, 386

Delile — (6).
Deloynes — (12).
Dement (38).

Desmaziéres 597 (51).

de Vichet — (6).

Dodge — (42); — (46); — (55); —
(58).

Doms — (12); — (51).

Dorfler 3698 (6).

Dowell 6455 (47).

Drushel 4664 (58).

Dudley 1043 (84); — (58).

Duggar — (58).

Durand — (48); — (58).

Durieu 21 (6); — (11); — (10); —
(15a); = ' (2bys var! (258)

C20) Col oie Oe)
Duseu — (40).

Dusen — (51).

Dutton 397, 198, 260 (42); 282 (48);
787 (54).

Duval-Jouve — (62); — (6).

Eames 9671 (42a); — (48); 5294
(-8a); — (58).

Eames & Godfrey 9604 (55);
9204a (58).

Eames, Metealf & Wiegand 5445 (42).

Eastwood — (34); — (26).

Eaton, ex herb. HE. (29); 387, 1244,
1455, 882 (31a); ex herb. #. (11);

8223,

1922]

PFEIFFER—-MONOGRAPH OF THE ISOETACEAE

441, 187, 699, 431, 425a, 482b,
488a, 364, 289, 197, 380, 192, 919,
677, 441, 913 (42); 351,163, 589,
898, 482c, 427, 217, 919 (46); —
(48); 351, 362, 900, 942 (48a);
440, 482C, 483B, 424, 431, 960, 197,
382, 378, 876 (55) 34824, 299, 432
(56); 489, 363; 364, 231, 1 (58).

Eaton — (48); 2 (58).

Eggert — (29); — (38); — (39); —
(58).

Eggleston 3026, 1785, 2201, 2472, 699
(42); 1786 (48); 2200 (55).

Ehlers 621, 817 (54).

Engelmann —, 1954 (29); — (385);
Se UE) Piers yee
(58).

Engler — (51).

Ennis — (48).

Fabre — (25).

Farlow — (42); — (58) 5 — (55).

Faull 3430 (58).

Faxon, E. & C. E. 10, vs Sy Le GS
(42); — (48); — (55); 7, 5 (58).

Fernald 220, 218, 219, 105, 1215, y, g,
2819, x, 1214, 2824, 186 (42); 186, y
(GS = a)

Fernald & Collins 311, 320, 316,154, 318
(42); 155, 319, 317 (54); — (58).

Fernald & Linder 19630, 19631 (55).

Fernald & Long 12340, 12839, 12342,
23118, 12341, 12838, 12343 (42);
19620, 28109, 15949 (55).

Fernald, Long "& Linder 19625 (54);
19627 (55).

Fernald, Long & Norton 12337 (42).

Fernald & Smiley 11496 (42).

Fernald & Weatherby 15950 (55).

Fernald & Wiegand 2405, 4411, 4406,
2402, 2401, 4401, 2400, 4410, £405,
2401, 4407, 4403, 2403 (42); 4409
(54) ; 2404, 4402 (55).

Fernow 2640 (43).

Fiori & Beguinot 1606 (7).

Fitch — (58).
Flett 1929” (42); 1980 (42a);
949 (50); 2084 (53).

Fl. Reg. Alg. 16 (10).
Forbes — (42).
Foucault — (11).

Frag. Fl. Alg. Exsic. 499 (15).
Franberg — (51).
Franzoni — (40).

Frost 6 (48); 18 (58).
Fuller — (42); — (58).
Furbish — (42).

Fyson — (5).

Galen — (58).

213

Gandoger — (10); — (15); — (25);
— (62).
Garber — , 2312, 82 (31); — (42).
Gattinger 3812, — (39).
Gautier — (6).
Hee ray? (40) ; re (51) ; 361 (62); —
11

Gilbert. — (42).

Gillman — (42).

Gorman 715 (42).

Grand Marais — (25); — (62).

Graves 142 (42); 145 (42a);
(48a); 139, 140 (55).

Graves & Bissell — (48).

Graves & Linder 19621 (55).

Gray — (29).

Greenman 3861 (38);
(55).

Grout — (42).

Grout & Eggleston — (55).

Gundersen — (42).

Guthnik (?) — (25).

Hall —, 693 (26); —, 859 (38); —
(58).

Hamilton 81051 (42);

Hanbury 1656 (25).

Harper 1010, 1429 (31); 843, 9651,
1046 (31a); — (42); 88, 310 (58);

144

2314 (42); 424

81051 (55).

2142, 1112 (58a).
Hartz — (42).
Harvey 2 (42); 5 es DELI (OL)

4 (54a); 3 (55).
Hector — (18).
Heldreich 899 (4).

Heller, A. A. & E. Gertrude 3482 (34).

Henderson 2894, 2978 (34); 2979, £786
(52).

Henry 9082 (42).

Hepp 599 (51).

Herb. Ball — (25).

Herb. Copineau — (6).

Herb. Engelmann — (6).

Herb. Fac. Scient. Monsp. — (6).

Herb. Font. norm. 99, 99bis (15).

Herb. des Flores Europeenes 25 (10).

Herb. Grand Marais — (62).

Herb. Martindale (Cheeseman Coll?) —
(18).

Herb. Motelay — (38).

Herb. Mus. bot. Berol. — (40).

Herb. Per Larson — (51).

Herb. Thurber — (48).

Herb. Wight Cryp. 4 (5).

Heribaud — (40); — (51).

Hieronymus 774 (32); — (51).

Hinsdale & Eggleston — (42).

Hitcheock 1068 (39).

Hoffman — (42).

Holt — (42).

214

Hopkins — (42).

Hornung — (51).

Howe — (34).

Howe & Blasdale — (384).

Howe & Lang 763, 1424 (54); 954
(42).

Howell — , 1521, 698 (34); — , 618,
1526 (26); — (35).

Howell & Howell 303 (26); — (34).

Huet de Pavillon — (15).

Hunt — (58).

Hy (le) 5 se (lc

Hylten-Cavallius —, 1771 (51).

Jaequel — (51).

James — (42); — (48).

Jenks — (58).

Jenks & Swan — (48).

Jenman — (3.5).

Jennings 6582 (42).

Jesup — (42); — (48).

Johnson — (27).

Jones — (34); — (35).

Joor — (38).

Junger — (40).

Kashyap — (5).

Kay — (62).
Kellogg — (35).
Kirk —, 289, 186 (17); — (18).

Klebsman — (51).

Klinsmann — (51).

Knight 14 (54).

Knipe — (58).

Knowlton — (55).

Kralik 187 (25).

Kupffer 14912 (40).

Lagrave — (51).

Le Grand — (12).

Leggett — (58).

Lehman — (63).

Leiberg 1149, 1656, 1663 (34); 39, 2939
(35); 71, 2971 (42).

Lemmon — (35a); — (35).

Le Roy — (40); — (51).

Lesquereux — (42).

LeTourneux — (15); — (15a); —
(15b).

Lloyd 198 (25).

Long 12341, 12888 (42).

Lovery — (54).

Lunt — (42); — (58).

Lutzow — (51).

Lyon 874, 875, 876 (42); — (54).

Mabille — (25).

Mackenzie — (38); 1025 (42); 1059
(58).

MacMillan, Lyon & Brand 177, 71, 70,
146, 198, 171, 170 (42).

Macoun 14219a, 14219e, 86878, 538
(26); — , 14212 (35); 14220, 14226,

[Vol. 9

ANNALS OF THE MISSOURI BOTANICAL GARDEN

14224, 14222, 24940, —, 86879,
14217, 14218, 14215, 14216, 582
(42); 14227 (42a);—(48); 14213,
76921, 84084 (48a); 81092, 14223,
81091 (55).

Magnus — (51).

Malinverni — (7).

Mandon — (6).

Mann — (42); — (58).

Marrson 14 (51).

Martin — (40); 19 (12).

Martindale — (42).

Maxon 432, 3886 (47).

MeAllister — (30).

MeDaniels 5446 (58).

MeMinn — (58).

MecMurphy — (34).

Mearns 2807 (85).

Meisner — (51).

Merrill —, 10, 1408 (42).

Milde — (51).

Miller 1, 2 (42).

Milligan — (38).

Morong —, 3853 (42); — (48; — (55);

(58).

Motelay — (6); — (10); 1903 (11);
a RES MG ee
(15a); — (25a). >

Mougeot — (51).

Mougeot & Nestler 111 (51).

Mouillefarines — (25).

Mueller — (19).

Munz 479 (58).

Nelson 1531, 3939, 4059 (34);
3737 (26).

Neyraut — (6); — (25a); — (62);
==) 15

Nichols 877 (54).

Nolte 1601 (51).

Nuttall — (26); — (48).

Oreutt — , 1242 (27).

Osborn — (20).

Overacker — (58).

Paine — (42).

Palmer 2355 (26); — (47); — (48);
21555, 20848 (39).

Parish 1440 (34).

Parker -— (42); — (48).

Parlin 1753 (42).

Parlin & Fernald 922 (42).

Parry — , 307 (35).

Pease 2249, 18790, 2775, 2670 (42);
2640 (55).

Peck — (26).

Perkins — (42).

Perrin — (51).

Pfeiffer 21 (38).

Piper 4209 (34); 2131,
2125 (50); — , 2817,

1117 (42);
1102 (53).

1922]

PFEIFFER—-MONOGRAPH OF THE ISOETACEAE 215

Piper & Hungate — (53).

Piper & Smith 651 (53).

Pl. Seculae 242 (15).

Poring — (51).

Porter 1953 (42); — (58).

Poyser — (48).

Praeger — (54).

Pringle — (35); 1447, 1718, 8796,
3459, 13261, 6660 (37); — (42);
— (42a) ; 3333 (49) ;— (52) ;—(384) ;

(54a).

Eapeaheest 105 (15).

Rand — (42); — , 2, 3 (54); — (55).

Rand & Redfield 31721 (55).

Rand & Robinson 927 (42).

Rau — (48).

Redfield 2530 (42); 2726 (54).

Reess — (40); — (51).

Reinhardt — (16).

Reinke — (51).

Reinsch — (51).

Retter — (51).

Reveliere — (15); — (25).

Reverchon 1177, 795, 3551, 8549, —
(38); — (62); — (25); — (15).

Rich — (42); — (58).

Robbins — (42); — , 7, 8, 9, 11, 14
(48); 10 (48a); — (54); 13 (58).

Robinson 385 (42).

Robinson & Schrenk 239 (55).

Rodway — (19).

Rolland 6284, 65 (42); 6230 (48a).

Rose & Painter 8168, 8216 (58).

Rosendahl 2050 (42a).

Ross — , 800 (62).

Royle — (8).

Rugel — (31).

Russell — (42).

Ruth & Ruth — (42); — (58).

Rydberg & Bessey 3520 (35).

St. John 90061, 90059, 90060,
1870, 1871, 680 (42).

Sanford 38 (42).

Sargent 27 (42).

Schildknecht & Thiry — (40).

Schlickum — (40).

Schmoll — (35).

Schonland — (61).

Schrenk — (42).

Schultz 778 (11);
781 (25).

Schweinfurth — (3).

Schweinitz — (54).

Sennen — (6).

Seymour 1017 (55); — (58).

Shockley — (52).

Shull 66, 67, 296, 305, 200, 201,
(47).

Shuttleworth — (62).

90058,

395, 395b (12);

252

Smiley 492, 747 (26).

Smith — (42); — (48); — (53); —
(58).

Soe. Bot. Edin. 183 (51). .

Soc. Cenom. Exsice. 482 (6).

Solms & Reess — (40).

Spruce — (21).
Stahl — (40).
Steele — (47).
Stone — (55).

Study — (40); — (51).

Sturtevant — (55).

Suksdorf 2369, 833, 2370,
1235, 2372, 2613, 2479,
642, 2617 (34); 917,
2614, 2615, £443 (26);
- (35); 2210 (42); 2371,
2367 (34a).

Swan — (48).

Tatnall — (58).

Thaxter — (55).

Thiry — (40).

Thomas — (52).

Thompson — (26); — (27); — (34).

Thompson & Thompson — (34); —
(27).

Thurber — (58).

Thurow 15 (38).

Tidestrom — (47).

Trelease — (35);
(59).

Tuckerman — (55).

Tuerckheim 3531 (36).

950, 2368,
2616, 2618,
2378, 2364,

— , 2875

2365, 2366,

1262, 1261, 1263

Tweedy — , 962, 417 (35); 416 (52).

Umbach — (34).

Underwood — (29); — (42); —
(42a); — (54); — (58).

Underwood & Cook — (42a).
Vaceari 503 (25).

Vahl — (42).

Van den Born — (40).
Varnberg — (51).

Vasey — (38).
Vasey & Coville — (47).
Victorin — , 61, 694 (42).

Violleau 427 (12).

von Schrenk 23° (58).
Vroom — (42).
Walker-Arnott — (51).
Wanderley — (6).

Ware 724 (42).
Warion 189 (15); — ,
(10).
Watanabe — (60).
Waters — (42).
Watson 1371 (42).
Webster — (53).
Weddell 16 (10).

187 (25); 188

[Vol. 9

216 ANNALS OF THE MISSOURI BOTANICAL GARDEN
Wetherby — (58a). Wolf — (38).

Wheeler 1227 (42). Wright 3912 (8).

Wicketson — (51). Zantziger — (48).

Wiegand 2402 (42). Zeller — (50).

Williams 1, — (42); — (58). Zickendrath — (40); — (651).

Winslow — (42); — (54).

INDEX TO SPECIES

New species, varieties, and combinations are printed in bold face type; syno-
nyms and page numbers having reference to plates, in italics; and previously
published names, in ordinary type.

Page Page
Calamaria ota ies ae 8 Be: 104 \Cephaloceratodon 2-2 104
GOSVOTSO) See eee EE ey ae 115 gymnocarpum —-----_--__--_-- 129
Gepinocialss) <2 - te Ee as 8s 107 NYS eae ee ee ee ee 128
UDUNE ee See eee ee 122 Isoetella ~-_--_---__----_------- 104
Gin aie vd ee en 125 : balay ee ee ae
ECOTUC yee s See s 207 soetes | —--~---~-~--~-----~----~--
Ralummert. sii. 2 aka me 143 adspersa —---------------- 115, 220
IBOPY Oni eee aN ae 116 aequinoctialis --_---_--------_ ft
IDA lera = Meee se See ee 152 at Roe ae ee py ee
coromandelina __..--.--------- 109 st ia ag ene earch gt = hee ape
va LE Tg EA yd, aI ba oC ele bs Nt PB 114 ery Nagy eer Es RIG = Lio iT
Drinnmondy = 2 seo es ee 125 ae eed A ee re a ea 138
[LEENA SEES ee 118 Pere, | Fok pre aE ae RE RIG:
Weariicc as 209 ALOTICH. 6222s ee ae eee 207, 232
Seems 5 ah GT POR ace Ga 154 Bolander -222-— 223 S252 25 143, 228
echinosp I a ac a le ae 127 Bolanderi var. Parryt_____---~_ 143
ee ee 136 Bolanderi var. pygmaea —-_--~-- 146
f laccida Wp aTey AAT LL eT Bolanderit var. Sonmet =-.—---—_- 143
COANE ae Boryana }i8e 20s he eae 116, 220
Gunnit_ —------~--------------~ 9 brachyglossa. 22 109
Le eS aera ae ae) Braue) I eee 156, 230
humilior ALM LANG ALT ee oe 208 Braunii forma robusta —-------- 173
we is aa an Shey ey a 123 Braunti var. maritima —-------_ 174
a 186 Brochont., 225) 3s8s ee 156, 230
lacustris —--—-----—---------~- weer lt adders 2S eee hae 152, 228
a sti iaa a Ay AR Me GARAGE ERAT S 119 Butleri var. immaculata ~------ 152
ete Y y Si aed) 2S 4
Malinverniana ————--—- EE amg -siehaeoeRag, Rite ICRI 184
melanopoda --—--—~---—-----—— aay canadensis var. Robbinsit ----- 184
melanosp SARE TET oT 1927 COPSULGTIS = So = aoe eee 109
20 tania Eo bates -
iter patna Be Be CaN To Chapman) 2222] ee eee ee
hres Ta aR A Resa ace ue coromandelinar (2-2 ee 109, ee
Sil eh aN acke saan PRX RR TT 1 ns Cubana, (22 a eee 113, 220
Perraldertana ---~-----------— oT decipiens KWEIUE LC RN 119
ae ARTIC CERES TOES 181 Detalandes Mii es a
ART te sae RD A Dodges es ater Ss ae ee
een wana === === ---- == === ive Dodge var. Robbinsii -_—______- 184
ea a a a a ae errr wr -(~ fs Bee ERI 224
Schweinfurthii ---_----------- 207 (RESPEC ee ORRIN CS eae ane
eae ae et) Davie ane, se
eae EE on: 7 TAT ON INTE PRT CAGES eT SON ae ee eee ee
baci dn Maen oars amne Ta ou echindspors’ | =. - 2322 L oe 154, 230
3 aA otal gee sel 2 are REET 138 echinospora var. asiatica__-_--~ 156
i heehee SLR ah ae OT 195 echinospora var. Boottii ------- 156

Welwitschii 106 echinospora var. Braunti —----- 156

1922]

PFEIFFER—MONOGRAPH OF THE ISOETACEAE 217
Page Page
echinospora var. Braunii forma emai ay, /e ee 147, 228
BOoGaw, 2555010 ee, 157 CCA (3) IIS Rodeo Aan oe Se a RS 142
echinospora var. Braunii forma Montesumae 2. 147
TODUSEG rete Venere Cee a 173 Miallora, Sve ei Cr Ry hve Pe 127
echinospora Brittoni _..__-____ 157 ALIN AS 31 ES A a a Ge 157
echinospora var. Flettit _______ - 186 ma teglen sag) Se a eS 210
echinospora var. maritima _____ 174 BeOpMineenais) te. Mn Loe oe * 211
echinospora var. muricata _____ 157 hebFg al AX; 2/21 baal gies Me ce alee eA 114
echinospora var. robusta _______ 173 AUIS LES Gala Se NN 139
echinospora var. truncata ______ 175 Diuppalian eee a ree ys 130, 224
CONTA KC Fas AUREUS OLAS SUPA A oa PET ot 208 Nuttall var. Orcuttii _______ 132
Blame ee VL ee 126 Gccidentalign =. 200i) ec 189, 230
Bmgolmauny| oe kuhr aie ie) 201, 232 occidentalis var. Piperit _.______ 190
Engelmanni var. caroliniana_207, 232 Oya ieee | Wee eee 3 te 118
Engelmanni var. fontana ______ 201 OY ITAA SNS eS ee EE NS LE 130
Engelmanni var. gracilis _____- 201 Orrcomng fay ats Nie 9 132, 224
Engelmanni var. valida __-____ 201 OWA aloe ok see eas Te 108, 218
THE CONG Eira tk Py Le ea 136, 226 DOMPDCTCULGA He 2 tes saa a Wa Tease 190
flaccida var. alata —-__--___ 137, 226 Perratdervana. a0) Va yy 121
flaccida var. Chapmani _______ 136 Biacpenere Te Or Le a 176
flaccida var. rigida _._________ 136 1PeTl ~-~--------=-------~--~ 190
Bier i aie bia Gs 186, 230 Pringlei —_--__-_.4/__ 2 J 185, 230
OME Ola tae see ve ete es ty 200, 232 bygmaea = —-_--__-____________ 146
Gasiniericiea,! iia) tee Fc eC 126 dese ay rea a SiGe 181, 230
raves ee th le Une 173 Tiparla var. canadensis _____ 184, 230
Grr ers nin tne 124. 224 saccharata —_-___<________ 179, 230
ROME UE LAL (Ue agp saccharata var. Palmeri _______ 179
Weldreichi, vildeois suber 109 ee var. reticulata ______ ie
9 BVveriera Sie See eRe
Pe loiianol Sag 7 yee ||| Babwetntactnd 107, 218
Pushes UN UE aN) Tak 128, 224 setacea _--____ =>>-------- 110, 218
histrix forma desquamata _____ 129 setacea var. Delilet Roa aes RB AT 119
histrix forma subinermis ______ 129 setacea var. Perreymondii______ 115
histria var. scutellata _._______ 129 OUD nnn nn 138
ROOK NAN Sieh sot ole SL 134 Stuartii Fae MR RTT 134
Bbawoniia flere 2 Is 139, 22g Sulisdorfit —_-——————-_________ re
ss are DSIVONVEE, Hie WL eae
see Meine Tor aal tae yl Herston) ma 181, #22
RADoMIEA woe Leki n. Wick ta 208 benuissiniay jens 7 2 12 ee edt e 117, 220
Karstenii Ba Me a ee Be 138 tenuissima Nuyda Oo 127
Ty ST a a ATS 123, g2¢ Tigultana ________________ Tar
iperairiagn | Wilh s Nh We 186, 230 | Fedentata —-———-—— oe
omnia ew te 18 1 Sn 18g ee ee ee tor aes ae rig
lacustris var. paupercula ______ 189 triquetra —~--—-_______________ 138
Mneehler a MO ee as se ety haes 138 truneata ->--------------- 175, 230
eamepora ee bl ek Gan ss 186 Tuckermani --------------195, 234
Mppsrec AAO SAN. CTL i Woo 209 Luckermani var. borealis eet ae 195
pola ei ULE bh lor 115 Tuckermani var. Harveys 22 ~ 192
“Fre sy] Sel tel 135. 226 Tuckermani var. heterospora ___ 192
longissima __-__-_____......... 120 Tuerckheimii ci ae SN PE aI 147, 228
RARCI Phd oe Cae FP SL ey 174 Uiquterwoo dan, | coe ee SS 139
FACTOS DOK Ay | poecas bees BE 192, 232 da Ra eo RET EG 177, 201
macrospora var. heterospora____ 192 Mane VaR STOVER ——— == 1 19. ae
macrospora forma percplyphres oy valata forma longissima ....... 120
Malinverniana BT SAE en 113, 218 velata var. longissima —-_______ 120
LPT EST Oe ae ae Len 174 velata var. Perralderiana----121, 222
iam ile bel oe) aes 200 Protaetss ots A SEE 117
meplamGpodsa: 22 ko Te 149, 22 Woelmyitsehi | ste eee i 106
melanopoda var. californica____ 139 Wommmauldtas cee vag AME 208
melanopoda var. pallida ______ T40)y Mawaleg == teeter 104
Mmelamonporg.s Ope oS LSA, (226 (MOUNTS esau eNO ee 104

[Vol. 9, 1922]
218 ANNALS OF THE MISSOURI BOTANICAL GARDEN

EXPLANATION OF PLATE

In this and the following plates, which are reproductions of photographs,
the magnification is approximately 21 diameters in all cases of megaspores.

PLATE 12

Fig. 1. Isoetes Schweinfurthii A. Br. Megaspores.

Fig. la. I. ovata Pfeiffer. Megaspores.

Fig. 2. J. coromandelina L. fil. Megaspores.

Fig. 3. J. setacea Bosc. Megaspores. |

Fig. 4. J. Malinverniana Cesat. & De Not. Megaspores.

EXPLANATION OF PLATE
‘PLATE 13 .

Pi . i

; f Fig. 5. Isoetes cubana Engelm. Megaspores.

: Fig. 6. I. adspersa A. Br. Megaspores.

4 me Fig. 7. I. Boryana Dur. Megaspores.

| Fig. 8. I. tenwissima Boreau. Megaspores.

? ' \

:

ny w . ; u nae
A , me A nN

Ann. Mo. Bor. Garp., VoL. 9, 1922. Pirate 13. .

PFEIFFER—MONOGRAPH OF ISOETACEAE

‘ase fo hs “i a
[Vol. 9, 1922]
222 ANNALS OF THE MISSOURI BOTANICAL GARDEN

EXPLANATION OF PLATE
PLATE 14

Fig. 9. Isoetes velata var. Perralderiana Pfeiffer. Megaspores.
Fig. 10. J. velata A. Br. Megaspores.

Fig. 11. JI. tegulensis Genn. Megaspores.

Fig. 12. JI. alpina Kirk. Megaspores.

Fig. 13. I. Kirkii A. Br. Megaspores.

Garp., VoL. 9, 1922.

Ann. Mo. Bot.

eal
Co
fr)
oe
C)
co
,
onl
fr)
Y
rer
Ga
Fx,
Ln nl
pa)
Ay
ba
wy
aye

EXPLANATION OF PLATE
PLATE 15

Fig. 14. Isoetes Gunnii A. Br. Megaspores.
Fig. 15. I. Drummondii A. Br. Megaspores.
16. I. histric Bory & Dur. Megaspores.
17. I. Nuttallii A. Br. Megaspores.
18. J. Orcuttii Eaton. Megaspores.

Ann. Mo. Bor. Garp., VoL. 9, 1922. Pate 15. an

PFEIFFER—MONOGRAPH OF ISOETACEAE

ANNALS OF THE MISSOURI BOTANICAL GAR

EXPLANATION OF PLATE

| PLATE 16 | fi
Fig. 19. Isoetes melanospora Engelm. Megaspores. % iy bi)
Fig. 20. I. lithophila Pfeiffer. Megaspores. ML aon
Fig. 21. JI. flaccida Shuttlew. Megaspores. : : fe sa rant
Fig. 22. I. flaccida var. alata (Small) Pfeiffer. Megaspores. oh

PFEIFFER—MONOGRAPH OF ISOETACEAE

SAA ;
ANNALS oF TEE anssounr BOTAN

ee _ EXPLANATION OF PLATE
| COT ae -PLATEI7 aOR

Le ed gage 23. Isoetes Howellii Engelm. “Megaspores. ry eto

‘Fig. 24. I. Bolanderi Engelm. Megaspores. _ at:

RK Fig. 25. I. Tuerckheimit Brause. Megaspores.

I say ‘Fig. 26. I. mexicana Underw. Megaspores. he .f As

ASRS E SES AL I. melanopoda Gay & Dur. Megaspores. iy ea a a
pa yesst ay Fig. 28. I Butleri Engelm. Megaspores. — yeaah Ura

PFEIFFER—MONOGRAPH OF ISOETACEAE

230

Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.

29.
30.
31.
32.
33.
34.
35.
36.
37.
38.
39.
40.

[Vol.

ANNALS OF THE MISSOURI BOTANICAL GARDEN

EXPLANATION OF PLATE
PLATE 18

Isoetes echinospora Dur. Megaspores.
I. Brochoni Motel. & Vendr. Megaspores.

SN NNR

. Braunii Dur. Megaspores.
. truncata Clute. Megaspores.

Eatoni Dodge. Megaspores.
saccharata Engelm. Megaspores.

. riparia Engelm. Megaspores.

. riparia var. canadensis Engelm. Megaspores.
. Pringlei Underw. Megaspores.

. Flettii (Eaton) Pfeiffer. Megaspores.

. lacustris L. Megaspores.

. occidentalis Hend. Megaspores.

9, 1922]

ISOETACEAE

7RAPH OF

VoL. 9, 1922

=
qi

|

|
YY
a4
(x)
he
es
fy
—
fr)
a2)
fr
jam
Ay

Bor. GARD.,

ANN. Mo.

232

Fig.
Fig.
Fig.
Fig.
Fig.
Fig.

41,
42.
43.
44,
45.
46.

[Vol. 9, 1922]
ANNALS OF THE MISSOURI BOTANICAL GARDEN

EXPLANATION OF PLATE
PLATE 19

Isoetes macrospora Dur. Megaspores.

I. macrospora f. hieroglyphica (Eaton) Pfeiffer. Megaspores.

I. Tuckermani A. Br. Megaspores.

I. foveolata Eaton. Megaspores.

I. Engelmanni A. Br. Megaspores.

I. Engelmanni A. Br. Megaspores with dust-like microspores in the

background, showing relative size.
Fig. 47. I. Engelmanni var. caroliniana Eaton. Megaspores.
Fig. 48. J. azorica Dur. Megaspores.
Fig. 49. JI. Duriaei Bory. Megaspores.

PLate 19

PFEIFFER—MONOGRAPH OF ISOETACEAE

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