Occasional Papers OF THE CALIFORNIA ACADEMY OF SCIENCES XIII SAN FRANCISCO Published by the Academy September 17, 1927 COMMITTEE ON PUBLICATION George C. Edwards, Chairman C. E. Grunsky Barton Warren Evermann, Editor Cretaceous Diatoms from California BY G. DALLAS HANNA Curator, Department of Paleontology » SAN FRANCISCO California Academy of Sciences September 17, 1927 ^i^OO Vol. XIII] HAHHA—CRETACEOUS DIATOMS ^ CRETACEOUS DIATOMS FROM CALIFORNIA BY G. DALLAS HANNA Curator, Department of Paleontology Introduction The occurrence of vast deposits of fossil diatoms in Tertiary strata in widely separated localities has so completely absorbed the interests of micropaleontologists in the past that very little knowledge exists regarding pre-Tertiary forms. In fact, it has been repeatedly stated in the literature that this group of uni- cellular plants came into being during the transition from Meso- zoic to Tertiary. Van Heurck, one of the greatest students of these organisms, writing in 1896, had this to say on the subject: "Deposits of fossil diatoms are numerous, and are found in very various localities. The most ancient is that found in 1878 by Mr. Shrubsole, of Sheerness-on-Sea, in the London Clay, which be- longs to the lower Eocene, Tertiary period."^ Up to that time, records of pre-Tertiary diatoms were accom- panied by some doubt and in certain cases had been proved to be false. Sometimes Tertiary strata were mistakenly classified and, again, impure collections were made from early rocks, containing later admixtures or even recent forms. The siliceous frustules are so exceedingly minute that the greatest care must be taken in making collections and preparing them to prevent this very thing happening. Also, they are readily carried from place to place by winds and water currents. In spite of the uncertainty attending the early records of pre- Tertiary deposits of fossil diatoms, evidence of late years has been accumulating to show that, at least in the later part of the Cretaceous, there was an extensive flora in existence. Some of this evidence is drawn from a comparative study of forms described many years ago. Other data are derived from strati- graphic facts. ' A Treatise on the Diatomaceae, London, 1896, p. 43. September 17, 1927 CAUFORHIA ACADEMY OF SCIEHCES [Oc. Papers In 1912, Otto Miiller described the peculiar genus and species, Actinoclava frank ei from the Turonian Shales from the middle part of the upper Cretaceous of Rilmerich, Westphalen.^ There was no doubt regarding the age of that species. Miiller referred to the literature on this subject and cited Rothpletz as having given the record of the earliest known diatoms, Lias or lower Jurassic.^ Rothpletz described two new species of Pyxidicula, which would now be referred to the genus Stephana pyxis, a group of pelagic forms. In view of the abundance of this genus in the California Cretaceous, one is led to suspect that some such pelagic marine form may have been the original ancestor of all the diatoms if they have not a multiple origin. My attention was originally called to Rothpletz' paper by Mr. Charles Lawrence Baker, of Berkeley, California. In 1915, Tempere & Peragallo classified the principal fossil localities of the world according to age and presented percentages of living species in each. Their table is so significant, that it is reproduced herewith : Age of important deposits of fossil diatoms and percentage of living species in each. By H. Peragallo." Location of Deposit Kiisnetzk [Russia] Ananino, Simbirsk [Russia] Jutland Antilles [Barbados, Hayti] Oamaru [New Zealand] St. Peter, Szakal [Hungary] Richmond [Virginia] ; Nottingham [Maryland] Santa Monica, Monterey [California] Moron [Spain] Greece, Algeria, Sicily The above classification is probably as good as could be made at that time, differences of opinion being of small value until - Diatomeenrest aus den Turonschichten der Kreide. Ber. Deutsch. Botanischen Gesellschaft, Vol. 29, 1912, pp. 661-668, pi. 26. * Rothpletz, A. Uber die Flysch-Fucoiden und einge andere fossile Algen, sowie iiber liasische Diatomeen fiihrende Hornschwamme. Zeitsch d. Deutsch. Geol. Gesell. Vol. 48, 1896, p. 910, pi. 23. * Diatomees du Monde Entier, ed. 2, 1915, p. 391. Percentage of living species Age 2.3 Cretaceous II-5 Cretaceous i6.i Cretaceous 1 1.9 Cretaceous 21. 1 Tertiary 40.0 Tertiary ] 44-0 Tertiary 41.0 Tertiary 47.0 Tertiary 66.6 Tertiary Vol. XIII] HANXA—CRETACEOUS DIATOMS 7 more is known of the stratigraphy of the various deposits men- tioned. Unfortunately, with few exceptions, information on this subject is very scant. It can be said definitely, however, that the localities mentioned from California, "Santa Monica and Mon- terey" represent the upper or middle part of the Miocene series. In view of this extreme scarcity of authentic records of diatoms in the Cretaceous, great importance must be attached to the dis- covery of these organisms in 1915 by Anderson & Pack in the large body of Cretaceous shale which they named Moreno.^ This formation outcrops along the west side of the great interior valley in the foothills of the coast ranges from Mount Diablo on the north almost to Coalinga on the south. In great part, it is dark maroon, purple or brown, thinly bedded and earthy. A character- istic feature of the formation is a series of sandstone dikes which traverse it in many directions. Hard gray lenses are often de- ^.i' "jT"""/ the shale body. These lenses are commonly called "limestone" /"v./o^' oc and the calcareous organisms, the Foraminifera and Mollusca.lV % ;' ^ < ¥ there are preserved intact; elsewhere these forms are represented ^"^^•.^*^ ^ ^,. ^ by moulds. There is much mineral matter in the lenses other than Vc^^p^ calcite and in many cases the rocks do not disintegrate in acids, v ~^' " The formation lies above definitely determined Cretaceous strata, the Panoche formation, consisting in large part of sand- stone. Above the Moreno Shale, extensive deposits of Eocene have been identified with certainty. For many years the Moreno Shale itself was classified as Eocene by several authors, chiefly owing to the character of its lithology and its stratigraphic position.^ But Anderson & Pack discovered molluscan fossils in the shale itself which definitely identified it as upper Cretaceous and their discovery has been amply confirmed by geologists work- ing with me. The Mollusca thus used to determine the age of the formation are Hamites, Baculites and other cephalopods. They occur in the lenses and in the shale itself in positions which abso- lutely preclude any supposition that they may be secondary. The type locality of the formation is described as follows by Anderson & Pack : ' U- S- Geol. Survey, Bulletin 603, 1915. »See Anderson & Pack, U. S. Geol. .Surv. Bull. 603, 1915, pp. 49-51, fcir a history of correlation prior to 1915. g CALIFORHIA ACADEMY OF SCIEHCES [Oc. Papers "The name Moreno is applied to the formation, from Moreno Gulch, on the east flank of the Panoche Hills, where it is typically exposed. [Northwestern Fresno County, California.] Here the formation has a thickness of 1,700 to 2,000 feet and is composed predominantly of thin- bedded, rather brittle brownish and lavender-colored shales, that weather into small bits and flakes. In the lower part of the formation, there are numerous beds of sandstone, locally containing poorly developed con- cretions and in general similar to the sandstone of the Panoche forma- tion. The upper half of the formation is more nearly pure shale and contains a greater proportion of material of organic origin. Calcareous shale, limestone nodules and layers of semi-porcelaneous siliceous shale occur locally, and near the top of the formation there is a zone of white, platy, diatomaceous shale about 200 feet thick. This zone is traceable most of the way along the face of the Panoche Hills. Large sandstone dikes traversing the shale are very conspicuous, a zone of several such dikes being traceable for most of the distance across the strike of the formation. Calcareous concretions are scattered through the shale, es- pecially in the middle of the formation, but are not so numerous as they are in this formation in some other localities. Besides the foraminifers, fossil mollusks occur sparingly, among them being Hamites or Anisoceras, characteristic Cretaceous forms." ' Adverting further to the occurrence of diatoms in the forma- tion, the authors had the following to say : "The discovery that the shale of the Moreno formation in places is in- distinguishable lithologically from the Tertiary shales of organic origin is one of the most interesting results of the field work. Hitherto strata of this type have been known in California only in the Tertiary. The discovery that this shale is diatomaceous is likewise important, owing to the fact that it is one of the main oil-bearing formations of the region, thus adding one more to the list of diatomaceous shale formations that are believed to be the ultimate source of oil in California. Before its diatomaceous nature was ascertained, it was believed by the writers, on the evidence of its stratigraphic relations, to be a source for part of the oil of this region. It therefore affords a good argument in support of the theory that the oils of California have a diatomaceous origin." ' In the early part of 1926 Mr. J. A. Taff, Mr. H. J. Steiny and I visited Moreno Gulch for the purpose of making collections at the type locality of the Moreno formation. We were able to check the observations of Anderson & Pack and a short paper was subsequently published covering the observations.^ The white (or buff) diatomaceous shale was discovered with ease and collections were made every ten feet across the strike 'U. S. Geol. Surv. Bull. 603, 1915, pp. 46-47. "Op. cit. p. 48. •Taff and Hanna, Bull. Am. Assoc. Petrol. Geol. Vol. 10, No. 8, 1926, pp. 812-814. Vol. XIII] HAXNA— CRETACEOUS DIATOMS ' 9 for a vertical distance of 400 feet. The portion which contains diatoms in appreciable numbers occurs in a zone somewhat less than 200 feet thick, the top being about 50 feet below the top of the formation at that point. The extreme top of the formation there is not highly organic and all that below the diatomaceous portion is of different character. There is some evidence to indi- cate that the greater portion has been largely organic in the be- ginning but the microscopic fossils have been decomposed be- cause of the instability of organic silica. Further research is necessary to determine this point definitely. The collections made across the strike were numbered con- secutively, the diatoms described herein having been taken chiefly from numbers 29, 30, 31 and 32, They are approximately 130, 120, 110 and 100 feet below the top, respectively, and were taken on a line about 150 feet north of the wash known as Moreno Gulch. The series of samples is numbered 943 in the California Academy of Sciences' record of fossil collecting stations. Man}- samples from this series, other than the three mentioned, were critically examined, but being either without diatoms or with comparatively few, they were not used for the selection of speci- mens for mounting. The presence of certain common species throughout the vertical distance of the series where diatoms oc- curred demonstrates the unity of the formation as a whole. The shales at this point were found to be excessively difficult to disintegrate so that the organisms could be properly cleaned and mounted for study. The difficulty was apparently due to the presence of a peculiar and very stable organic cementing sub- stance. After much experimentation, it was found that a measure of success could be had by protracted boiling in concentrated sulphuric acid in the presence of copper sulphate. The carbon which was thus diffused through the acid was decomposed with potassium chlorate. After removal of acids and salts the pieces of shales could then be disintegrated by cautious boiling in con- centrated caustic soda. It was, of course, necessary to neutralize this substance very quickly in order to prevent partial decomposi- tion of the siliceous fossils. The diatom flora described and figured herewith is not a large one as such floras go, but it is extremely interesting in many re- 10 CALirORXIA ACADEMY OF SCIEHCES lOc. Papers spects. Many more species will undoubtedly appear on careful search ; in fact a considerable number not mentioned herein have already been picked out but await satisfactory determination. Most interesting of these are several more species of Trinacria and a fine Arachnoidiscus. The assemblage of genera and species is wholly unlike that of any other known deposit. It is the first recorded Cretaceous diatom flora from the Americas. The stratig- raphy and age of the deposit is probably better known and de- scribed than any other deposit of Cretaceous diatoms anywhere. There can be absolutely no excuse for confusing these Cretaceous organisms with those of the vast and widely known deposits of the California Miocene, the dissimilarity being so great. The occurence of genera and species hitherto undetected would be expected in view of the little that has thus far been done on Cretaceous diatom floras and the discovery of these is just as exciting to the diatomist as would be the discovery of Ammonites or related forms by the student of molluscan paleontology. An attempt at correlation of the Moreno deposit with others elsewhere would be premature at this stage of the study of Cre- taceous floras but at least a suggestion is offered in the large number of species belonging to the genus Trinacria. A similar assemblage with some identical species occurs in northern Russia at Archangelsk-Kurojedowo in Simbirsk. ^° The collection upon which this study is based has been pre- pared and mounted according to the methods and standards gen- erally accepted as best for museum preparations. Only one species is placed on a slide. The genera and species are arranged alpha- betically, all type material being properly designated on the slides. Besides the diatoms, the shales studied contain several species of silicoflagellates and many radiolarians ; these organisms were mounted separately, when found, but have not as yet been criti- cally studied. The type material in the custody of the Department of Paleon- tology of the California Academy of Sciences has been segregated from the general collections and the various specimens are num- bered serially beginning with one. Since 1914, the numbers as- signed to the types, etc., have been published with descriptions but the collection contains many additional specimens, the present "See Witt, Verhandl. Russ. Kais. Mineral. Gesellschaft, St. Petersburg, Vol. 22, Ser. 2, 1886, pp. 137-177, pis. 6-12. Vol. XIII] HANNA— CRETACEOUS DIATOMS H location of which is not generally known. This material was acquired through the donation to the Academy of several note- worthy collections. It is contemplated that a catalog of the type collection will be published at some future time, and with this in mind it has all been systematically labelled and indexed. After much consideration, the classification of the several cate- gories of type material designated by Messrs. Schuchert & Buck- man in 1905 has been adopted.^^ Since their paper is not available in many western libraries, a summary of a part of their classifica- tion is given below to properly explain the use of certain terms in the following pages. Holotype. The only specimen possessed by the nomenclator at the time of the description of a species; the only specimen used by the nomen- clator in the diagnosis of the species; the one specimen definitely selected or indicated by the nomenclator as "the type" ; the one specimen which is the basis for a given or cited protograph. Syntype (more correct than cotype). A specimen of the original series when there is no holotype. Paratype. A specimen of the original series, when there is a holotype and used in the diagnosis of the species. Lectotype. A syntype chosen subsequently to the original description to take the place which in other cases a holotype occupies. Plesiotype. A specimen identified with an already described and named species, but not selected by the nomenclator himself at the time of describ- ing the species and such specimen having been used in further amplifying the characters of the species. Topotype. A specimen of a named species from the locality of the holotype or lectotype — in paleontology from the same locality and horizon. Whenever the term "type" is used, it should be understood that "holotype" is meant. The dropping of the term "cotype" com- pletely, is strongly advocated because of the many meanings which have been assigned to the word in the literature. In addi- tion to the segregation of the type collection distinguishing colors are used to further identify the specimens. Holotypes and syn- types are marked with red ; paratypes are marked with orange ; and plesiotypes are marked with blue. In the case of macroscopic fossils this is done with a small spot of paint on the specimens themselves. Microscopic slides are marked with properly colored labels. "Annals and Magazine of Natural History, Ser. 7, Vol. 16, 1905, pp. 102-104. 22 CALIFORNIA ACADEMY OF SCIEKCES [Oc. Papers I am greatly indebted to Messrs. J. A. Taff and H. J. Steiny for assistance in making the collection upon which the study is based; to Mr. and Mrs. Wm. M. Grant for assistance in prepara- tion of the illustrations ; and to Dr. Albert Mann for helpful sug- gestions in nomenclature. Description of Species 1. Actinoptychus packi Hanna, new species Plate I, figures i, 2, 3 Valve circular, robust, divided into six equal sectors with a hyaline space in the center ; alternating sectors bear, in the center near the margin, a heavy, blunt marginal process set in a small hyaline area which is extended as a fine line toward the center; projecting beyond the margin of the disk, but not beyond the outer boundary of the hyaline border, there is a row of sharp spines, spaced almost equidistantly ; near the outer corner be- tween sectors, there is an irregular, hyaline area, and the sectors which do not bear the heavy spinose processes also have such a space in the center; sectors which bear spinose processes are covered with small, close-set beads arranged in rows approxi- mately in quincunx ; other sectors bear close-set beads of the same size but arranged in no definite order except near the margin where they are roughly radial ; the valve has a mottled appearance under high magnification due to unevenness of the interior surface. Diameter, holotype, .0865 mm. ; paratype, (1993), .0657 mm.; paratype, (1994), .0764 mm. Holotype: No. 1992; paratypes: Nos. 1993, 1994 Mus. Calif. Acad. Sci. from Moreno Gulch, Fresno County, California; upper Cretaceous. The species clearly belongs with the diatoms which may be grouped around A. grundleri Schmidt but differs from any of them in many notable characters. Most conspicuous of these, per- haps, is the fact that alternating sectors do not have similarly arranged heading. To show this necessitated the making of more than one photograph on account of the sectors not being in the Vol. XIII] HAHHA— CRETACEOUS DIATOMS J 3 same plane. It should be noted also that the margin is almost in one plane (focus) but it is the sectors which are raised and de- pressed. Actinoptychus simbirskianus Schmidt^^ from the Cretaceous of northern Russia is a species with the markings arranged in no regular order but lacks small marginal spines entirely and has differently formed blank areas. This species is named for Mr. R. W. Pack, who, in collabora- tion with Mr. Robert Anderson first discovered that the Cretace- ous shale at this locality was diatomaceous. 2. Actinoptychus taffi Hanna, new species Plate I, figure 4 Valve circular, divided into six equal sectors with a hyaline space in the center; three of the sectors each have a blunt spine in the center of the outer edge and from the spine a low ridge extends part way toward the central area ; border narrow, hya- line ; under the highest possible magnification with dry objectives and direct illumination the sectors present a hexagonal, mottled appearance due to the irregularities of the inner surface ; with oblique illumination, however, very fine close-set lines are seen covering the sectors and crossing in quincunx ; immersion ob- jectives of N. A. greater than 1.0 are necessary to resolve these lines into the beads of which they are composed. Diameter, .0656 mm. Holotype: No. 1995, Mus. Calif. Acad. Sci. from Moreno Gulch, Fresno County, California; upper Cretaceous. Although this is a relatively large diatom, the markings are so exceedingly fine that careful manipulation is necessary for their proper resolution. Some of the forms of the protean A. undulatus approach this species, but all appear to be much more boldly marked. The species is named for Mr. J. A. TafT who aided in making the collection upon which this report is based and who has been associated with the writer in many other investigations. "Atlas, Diat. pi. 29, 1875, fig. 11. J4 CALIFORNIA ACADEMY OF SCIEHCES [Oc. Papers 3. Aulacodiscus cretaceous Hanna, new species Plate I, figure 5 Valve small, thin and delicate, with four heavy spatulate spin- ous processes and a thin hyaline line radiating from each to a small central hyaline area; space enclosed by the four processes sparsely dotted with large, irregularly arranged beads having a higher focus than the general beading of the disk ; disk covered with fine beads arranged in radial rows and near the margin in diagonal rows likewise ; border narrow. Diameter, .071 mm. Holotype: No. 1996, Mus. Calif. Acad. Sci. from Moreno Gulch, Fresno County, California; upper Cretaceous. A. barbadensis Ralfs" is similar to this species but has the heavy beads distributed over the entire disk, forming a definite row just inside of the border; moreover the beading of the disk in that species is much coarser, according to Schmidt's figure. 4. Aulacodiscus pugnalus Hanna, new species Plate I, figures 6, 7 Valve of medium size, rather heavy and opaque in parts ; four heavy spinous, rounded processes near the margin with raised dagger-like projections extending toward the center; square space enclosed by the processes higher than remainder of disk; beads in radial rows, smallest near the margin, increasing in size and tending to anastomose toward the center; an irregularly shaped central hyaline area ; border of medium width. Diameter, .104 mm. Holotype: No. 1997; paratype: No. 1998, Mus. Calif. Acad. Sci. from Moreno Gulch, Fresno County, California; upper Cretaceous. Although there are numerous species of four-spined Aulaco- discus illustrated in the literature, the counterpart of this one has not been seen. The nearest to it appears to be a five-spined species from Simbirsk, A. septus Schmidt." Many individuals from the '"A. Schmidt Atlas, Uiat. pi. 146, 1890, fig. S. " See Witt, Verh. Russ. Kais. Mineral. Ge.sell. St. Petersburg, Ser. 2, Vol. 22, 1886, p. 158, pi. 6, fig. 11. Vol. XIII] HAHHA— CRETACEOUS DIATOMS 15 Moreno shale have passed under view but in no case has the number of spines varied from four and Witt remarks upon the equal constancy of septus. The species is chiefly marked by the sharp projections from the processes toward the center and the elevated area enclosed by the processes. A paratype, which I feel sure is the same species, is marked by the sparseness of the bead- ing in areas between the spines and by the comparative heaviness of the beads. 5. Auliscus aenigmus Hanna, new species Plate I, figure 8 Ovate, almost circular with ocelli of one valve, almost at op- posite ends of the short diameter, of the other valve at opposite ends of the long diameter; ocelli circular and with rims project- ing slightly above surface of valve; very fine striae radiate out- wardly from the ocelli but these leave, in the center, an ovate area uniformly granular throughout; in some parts the granules of this area present a beautiful wavy appearance which, as usual, is an indication of the use of insufficient aperture. Greatest di- ameter, .0429 mm. ; least diameter, .0412 mm. Holotype: No. 1999, Mus. Calif. Acad. Sci. from Moreno Gulch, Fresno County, California; upper Cretaceous. The markings of this diatom are so exceedingly fine that high apertured objectives are necessary to properly resolve them. No similarly sculptured form could be found in the literature. The species is apparently rare in the deposit and the type specimen has both valves attached ; this accounts for the irregularly shaded areas in the photograph. A. piilvinatus Cleve^*^ from "Miocene or Pliocene" of Moravia although finely marked is fully twice as large as the present species and the central area is conspicuously elevated and depressed in concentric zones. Benetorus Hanna, new genus Valve circular, almost flat, with an outer annular zone of rows of coarse, radiating beads and a central circular area, hyaline at v^^^^ft^^V ■"Journ. guekett Micr. Club, Vol. 2. Ser. 2, 1885, p. 171, pi. 13, fig. 9. ^ A/'xV??^ r, \. 1^ CAUFOKH.IA ACADEMY OF SCIEHCES [Oc. Papers least in part and almost enclosing a pyriform beaded area in the center. Genotype : Benetorus fantasnius, new species. Benetorus fantasmus Hanna, new species Plate I, figures 9, 10 Valve circular or almost so, almost flat, slightly depressed at the margin ; outer, annular zone uniformly marked with radial rows of coarse beads ; these increase slightly in size toward the margin and the rows are distinctly separated by hyaline lines somewhat as in Stictodiscus; this outer zone encloses a hyaline circular area which in turn has, in the center, a pyriform beaded area, the beads not being arranged in any definite order; this pyriform area is connected to the outer annular zone by a narrow neck and on one side of this in the hyaline area there are rows of very faint radiating beads ; these rows become more and more obscure as the distance from the isthmus increases and they gradually fade out completely before a quadrant has been passed. Diameter, holotype, .050 mm. ; paratype, .0528 mm. Holotype: No. 2000; paratype: No. 2001, Mus. Calif. Acad. Sci. from Moreno Gulch, Fresno County, California; upper Cretaceous. The literature does not appear to contain the description or figure of any diatom closely allied to this remarkable form. As a genus it does not appear to have a close relative, although the outer markings are suggestive of those of some "Cretaceous"? Stictodiscus from Hayti. The above description is from the holo- type specimen. In the paratype (figured) the shape is not quite circular and the enclosed hyaline space is slightly cordiform in shape. The species is rare in all of the samples examined. 6. Cladogramma jordani Hanna, new species Plate 2, figure i Valve circular, flat, small, with very narrow border; markings consist of narrow lines radiating from near the center to the border and enclosing somewhat irregularly shaped hyaline spaces. Diameter, .0289 mm. Vol. XIII] HAHHA— CRETACEOUS DIATOMS 17 Holotype: No. 2002, Mus. Calif. Acad Sci. from Moreno Gulch, Fresno County, California; upper Cretaceous. The genus Cladogramma Ehrenberg," has C. californicum for the type species; it came from a deposit of Monterey (Miocene) shale from San Francisco Bay. According to Van Heurck^* the genus contains four species ; two of the other three are C. conicum Greville^^ from Barbados and C. cebuense Grunow^^ a living species. All of these are marked in similar manner to the one here being described but all are more or less conical in the center ; C. jordani is flat. The species is named for the late Eric Knight Jordan, formerly Assistant Curator of Paleontology, California Academy of Sci- ences. 7. Coscinodiscus immaculatus Hanna, new species Plate 2, figure 2 Valve circular, almost flat, border heavy; markings consist solely of very indistinct and irregular blotches where there is a slight unevenness in the silica. Diameter, .0860 mm. Holotype: No. 2003, Mus. Calif. Acad. Sci. from Moreno Gulch, Fresno County, California; upper Cretaceous. This species is abundant in some of the samples from the type locality. The silica is usually cracked in the preservation, thus producing "hair lines" in photographs. The faint markings are practically invisible with ordinary lenses and illumination. The photograph shown herewith was taken with full 1.40 N. A. in order to show all possible details. No other Coscinodiscus known to me is so lacking in sculpture. Were it not for the fact that otherwise the structure of the frustule conforms exactly to that of Coscinodiscus, it might reasonably be included in a separate generic group. It appears to bear no close relationship with Melosira and does not grow in chains. Tempere & Brun^^ de- scribed "Ethmodiscus (Pantocsekiaf) vitrifacies" from Japan which is likewise without visible markings but it is very convex like Podosira. " Microgeologie, 1854, pi. 33-13, fig. 1. "Treatise, Diat. 1896, p. 502. " Trans. Micr. Soc. London, 1865, p. 24, pi. 3, figs. 1-3. "Van Heurck, Op. cit. fig. 246. "Diat. Foss. Japan. Mem. Soc. Phys. Hist. Nat. Geneva, Vol. 30, pt. 2, 1889, p. 37, pi. 8, figs. 11 a. b. September 17, 1927 |g CALIFORKIA ACADEMY OF SCIEKCES [Oc. Papers 8. Coscinodiscus morenoensis Hanna, new species Plate 2, figures 3, 4 Valve circular, almost flat, coarsely marked with closely set beads arranged in rows, those in the center being smallest; the surface is divided into sectors of fasicules of unequal size, there being 12 in the type, but the number is variable ; a radial row of beads extends from center to margin through the middle of each sector, the remainder of the rows in that sector being parallel to the radial; also the beads of each sector are so adjusted as to size that they form rows, diagonal to the radii in two directions ; thus a perfect "watch case milling" would be formed were it not for the sector divisions ; border very narrow, marked by cross lines ; dividing the diatom by a diameter, one side is depressed, the other elevated in the central area and this culminates in the center by a concave and convex conical form ; the one which is convex, when looked at from the outside of the valve, ends in a short blunt spine ; the depressed portion terminates on the outside in a central hyaline area surrounded by coarse, closely set beads. Di- ameter, holotype, .216 mm. Holotype: No. 2004; paratype, No. 2005, Mus. Calif. Acad. Sci. from Moreno Gulch, Fresno County, California; upper Cretaceous. This large, handsome diatom is very common in the Moreno Shale. The single depression and elevation in the center of each valve is a remarkable feature apparently unknown in any other form although it is suggested in C. excavatus Greville^" from younger strata of eastern North America. In that species there are three protuberances and three depressions somewhat removed from the center of each valve. C. nodulifer Schmidt^"* has a small nodule near the center of each valve but lacks the cor- responding pit, has larger markings, a heavier border and the markings are not fasciculate. The peculiar depression and eleva- tion in the center of morenoensis are easily detected with an ordinary pocket lens in the field, thus making this species an ex- ceedingly valuable one for recognition of Cretaceous strata from Tertiary. ■■'o Schmidt, Atlas, Diat. pi. 65, fig. 1.— Wolle Diat. N. Am. 1894, pi. 90, fig. 1. '«'» Schmidt, Atlas Diat. pi. 59, figs. 20-23. Vol. XIII] HAHHA—CRETACEOUS DIATOMS ig 9. Coscinodiscus steinyi Hanna, new species Plate 2, figures 5, 6 Valve circular, very convex in the center, gradually flattening toward the margin ; border hyaline, narrow ; under low magnifica- tion or when slightly out of focus the diatom has a most remark- able, large, central star-shaped area presumably formed by some internal structure; surface divided into numerous fascicules, all densely covered with small beads ; these are arranged in rows approximately parallel to the rows which bisect the sectors ; center with a small hyaline area; numerous beads, irregularly scattered among the others, are very dark, almost black in transmitted light thus producing an irregular mottled appearance. Diameter, holo- type, .0908 mm. Holotype: No. 2006, Mus. Calif. Acad. Sci. from Moreno Gulch, Fresno County, California; upper Cretaceous. This remarkable diatom is possibly a relative of such as C. kocJiii Pantocsek^^ but the beads in that form are not so dense, the central area does not appear from the drawing to be convex and the dark markings are not so numerous. C. steinyi is very abundant in the Moreno Shale and under low power, dry objectives, is a light brown color. The species is named for Mr. H. J. Steiny, who aided in making the collection upon which this study is based and who has been associated with the writer in many field investigations. Glorioptychus Hanna, new genus This is a member of the family Actinoptichse, being divided into alternately raised and depressed sectors ; these, however, ex- tend outwardly only part way to the end of the radius, the re- mainder being divided into a greater number of alternately raised and depressed areas; markings double. Genotype : Glorioptychus callidus, new species. " Beit. Kennt. Foss. Bac. Ungarns, pt. 1, 1886, p. 71, pi. 22, fig. 197. 20 CALIFORNIA ACADEMY OF SCIEHCES [Oc. Papers 10. Glorioptychus callidus Hanna, new species Plate 2, figures 7, 8 Valve circular, with a central hexagonal, hyaline area ; divided into six alternately depressed and elevated compartments ; these sectors radiate from the central hyaline area, extending outwardly two-thirds the length of a radius ; the region from the outer ends of the sectors to the margin is divided into 18 alternately elevated and depressed areas, there being three to each of the central sectors ; the center one of each group of three border areas bears a blunt spine, there being six in all ; border zone moderately broad and hyaline ; the entire surface, except the central area, is covered with coarse, irregularly spaced points or elevated beads connected by bars of silica into an anastomosing network; in addition to these the surface is covered with a system of fine closely set dots in rows similar to many species of A^tinoptychus. Diameter, .0681 mm, Holotype: No. 2007, Mus. Calif. Acad. Sci. from Moreno Gulch, Fresno County, California; upper Cretaceous. This remarkable species is abundant in the Moreno Shale and variation from the holotype as described and figured is very slight. It clearly belongs in the same group with Actinoptychus but in no member of that group known to me is there an indica- tion of such a development in the border zone as is here found. Many complete f rustules were split and mounted and both valves are alike ; no internal plate was present in any specimens so ex- amined. 11. Hemiaulus pol)miorphus Grunow Plate 2, figures g, lo Hemiaulus polymorphus Grunow, Schmidt, Atlas, Dial. pi. 143, 1890, figs. 1 1- 13, 30-34. This remarkably variable species is common in the Moreno (Cretaceous) Shale, but does not seem to develop so many forms as have been heretofore referred to it. The most common shape is that illustrated herewith, corresponding to fig. 32, (plate 143 of Schmidt's Atlas), from Barbados. In one form or another, this species has been found in most of the fossil deposits of the Vol. XHl] HANNA— CRETACEOUS DIATOMS 21 world. According to Schmidt, Witt considered H. proteus Heiberg as having priority but diatomists generally adhere to Grunow's name. Length, .052 mm. ; height including spine, .0236 mm. Dimensions are exceedingly variable ; those given are of the speci- men figured in side view. Horodiscus Hanna, new genus Valve circular, with a central area marked with coarse bars of silica and a marginal zone of finer bars and irregular, large dots ; markings arranged roughly radially. Genotype : Horodiscus macroscriptus, new species. 12. Horodiscus macroscriptus Hanna, new species Plate 2, figure ii Valve circular, slightly convex, border, narrow ; close to the border there is an annular zone of short radial costse, followed inwardly by a zone of equal width which is granulose ; the mark- ings in this last zone are arranged in no regular order or pattern ; the zone is followed by the central area which is heavily marked with irregularly spaced ridges ; these are roughly radial, some- times branching, and at the outer margin of the zone develop into a sort of cellular structure. Diameter, .0525 mm. Holotype: No. 2010, Mus. Calif. Acad. Sci. from Moreno Gulch, Fresno County, California; upper Cretaceous. This remarkable diatom differs notably from any species of Hyalodiscus (or Podosira) known to me! yet in its essential char- acters it conforms to the general pattern of that genus. Normally, Hyalodiscus develops an outer zone of fine beading, the pattern being called "watch case milling," because of the geometrical arrangement, but in this species there is not the faintest sugges- tion of such structure. The rugose central area, however, al- though greatly different in detail, resembles the similar structure of many species of Hyalodiscus. The species was very seldom found in the various lots of ma- terial from Moreno Gulch. 22 CALIFORNIA ACADEMY OF SCIEHCES [Oc. Papers 13. Kentrodiscus aculeatus Hanna, new species Plate 3, figure 6 Cylindrical, acutely conical at the end of the valve, the cone terminating in a long straight or sHghtly curved spine ; lower end of spine and top of cone bearing small scattered, acute spines; central border zone marked with fine wavy lines and dots. Di- ameter, .0336 mm. Holotype: No. 2015, Mus. Calif. Acad. Sci. from Moreno Gulch, Fresno County, California ; upper Cretaceous. This species is allied to K. fossilis Pantocsek, but is much more acutely conical and bears a longer superior spine. It is not as common in the deposits as K. andersoni, which, although similar in shape seems to have no intergradation with the more cylindrical and finer spinose K. aculeatus. Some Moreno specimens are much longer in proportion to diameter than the one illustrated. The following is a partial synonymy of the type species of the genus : Kentrodiscus fossilis Pantocsek, Beit. Kennt. Foss. Bac. Ungarns, pt. 2, 1889, p. 75, Ananino, Russia. Kentrodiscus (Dicladia?) russicus Pantocsek, Op. cit. pi. 23, fig. 350. "Kentrodiscus hungaricus Pant." Van Heurck, Treat. Diat. 1896, p. 430, fig. 50. Ketrodiscus hungaricus Van Heurck, Op. cit. p. 430. Kentrodiscus was established by Pantocsek in 1889 for a species found fossil in Russia. Unfortunately he failed to use the same specific name in the explanation of his plate as he did in the text. It would seem that the name in the text, having page precedence, should be adopted. I cannot find that Pantocsek ever described a species named hungaricus although Van Heurck attributed the name to him. Van Heurck's figure is not copied from the original of K. fossilis so he may have been dealing with a specimen sent to him from Hungary as the name suggests ; his spelling "Ketro- discus" was probably a typographical error. Van Heurck considered the genus Kentrodiscus entitled to no greater than subgeneric rank under Pyxilla and Forti^^ merged it ^Nuova Notarisia, Vol. 20, 1909, pp. 19-38, pis. 1, 2. Vol. XIII] HAHHA— CRETACEOUS DIATOMS 23 with Pterotheca but in view of the profound structural differences disclosed in the present study, I feel obliged to retain it as a distinct genus. 14. Kentrodiscus andersoni Hanna, new species Plate 3, figures 6, 7 Frustule, inequivalve ; in girdle view one has a long blunt spine, somewhat curved from the central axis ; this valve is conical, the point of attachment of spine and cone being marked by numerous short spines which continue on over the surface of the valve ; girdle narrow; inferior valve without the large spine, much less convex than the superior, and with a few spines of almost uni- form size in the center of the valve ; sparse black dots form a zone near the border. Diameter, holotype, .0362 mm. Holotype: No. 2016; paratype: No. 2017. Mus. Calif. Acad. Sci. from Moreno Gulch, Fresno County, California; upper Cretaceous, The species differs from K. aculeatus by having much coarser spines. A view of the inferior valve of fossilis was not given by Pantocsek but the girdle view does not indicate that the spines have any such arrangement as do those of this California diatom. The spines of the inferior valve are more or less irregularly con- nected with low bars of silica, much as in Liradiscus. The species is named for Robert Anderson, who, with R. W. Pack, made the original discovery of diatoms in the Cretaceous shales of California. 15. Liradiscus ovalis Greville Plate 3, figure 5 The genus Liradiscus was created in 1865 by Greville for four species from Barbados. ^^. The first described species is L. barbad- ensis and this may be considered the genotype. Of the known species, the one from the Moreno Shale most resembles L. ovalis Greville.^* The oval disk is spinose, the spines being more or less =" Trans. Micro. Soc. London, Vol. 13, n. s. 1865, p. 4. ="Op. cit. p. 5, pi. 1, figs. IS, 16.— Van Heurck, Treat. Diat. 1896, p. 511, fig. 260. 24 CALIFORNIA ACADEMY OF SCIEHCES [Oo. Papbm perfectly connected with lines of silica which follow no regular order. The valves are very convex and alike. The group, it would seem, is closely related to Xanthio pyxis. The deposit on Barbados Island has been said to be Cretaceous in age,^** but apparently it is not the exact time equivalent of the Moreno Shale ; Payne^^ has recently put the strata in the Tertiary and it seems likely to me that he is correct. Meretrosulus Hanna, new genus The genus is apparently a member of the family Auliscse. Valve ovate, roundly pointed on the ends with ocelli at the ends of the long diameter ; central area with concentric circular areas, hyaline and radially sculptured alternating. Genotype : Meretrosulus gracilis, new species. The relationship of the genus seems to be with Auliscus but no members of that group are very close. 16. Meretrosulus gracilis Hanna, new species Plate 3, figures g, lo Valve flat, ovate, roundly pointed at the ends and with ocelli just inside the border; ocelli bordered by a row of minute beads; central area with a large zone of short radial strisB which cannot, apparently, be resolved into lines of beads ; this zone reaches the border in the widest part of the diatom ; inside of this zone there is another, hyaline, a little wider than the first; and inside the hyaline zone there is another circular area of radial striae, this zone being broader still; lastly the central area is hyaline, very slightly granular ; border very narrow and hyaline with a row of beads just inside of that part which extends from the largest ring of strise around the ocelli at the ends. Holotype: No. 2019; paratype: No. 2020, Mus. Calif. Acad. Sci. from Moreno Gulch, Fresno County, California; upper Cretaceous. ^"> See classification by Peragallo on p. 6. ^ Liostephania and its allies. London, 1922, p. 21. Vol. XIII] HANNA— CRETACEOUS DIATOMS 25 The exceedingly beautiful diatom has no close relative which I have been able to find in the literature. It seems to belong to a general group with Auliscus but has no very close relationship with any of the members of that genus. Dr. Mann^* has examined this diatom and has called my atten- tion to the resemblance of the central area to that of Glyphodiscus. G. stellatus Greville is very common in the upper part of the Monterey (Miocene) Shale in California and many specimens have recently been mounted. I believe the resemblance of central areas to be accidental and not the result of direct genetic relation- ship ; the diatoms are so very distinct structurally, that it hardly seems possible to include them in the same group. 17. Melosira fausta Schmidt Plate 3, figures ii, 12, 13, 14 Melosira fausta Schmidt, Atlas, Diat. pi. 172, 1892, figs. 3-10; Atlantic City, New Jersey; probably from Tertiary deposits. This large and handsome species, common in the Moreno Shale, was distinguished by Schmidt by the blank space between the interior, radially marked portion and the coarsely sculptured border. He also stated that it occupied a rather intermediate position between M. major and M. siberica. The presence of the radially marked central area is not at all constant and the charac- ter of the border sculpture likewise varies as the photographs herewith show. It hardly seems desirable, however, to attempt to recognize more than one species in this deposit. It is exceedingly common in all samples studied. Micrampulla Hanna, new genus Diatom minute, globular, slightly flattened on base, with a long heavy spine on top, thus resembling a Florence flask in shape; globose portion heavily sculptured. Genotype : Micrampulla parvula, new species. -■» In letter. 25 CALIFORXIA ACADEMY OF SCIEHCES [Oc. Papers 18. Micrampulla parvula Hanna, new species Plate 3, figure 15 Diatom, flask-shaped, with globose body heavily sculptured with slightly-projecting, blunt protuberances; base slightly flattened and on top a long, heavy spine. Diameter, .0087 mm. ; height with spine, .0230 mm. Holotype: No. 2025, Mus. Calif. Acad. Sci. from Moreno Gulch, Fresno County, California; upper Cretaceous. Much difficulty has been experienced in properly classifying this particular organism. Although apparently allied to Pyxilla and Pterotheca, it differs so much from any known member of that group or the general concept of the group as a whole that I cannot place it there. Individuals are not uncommon in the light- est washings of the Cretaceous samples. Just how they grew is problematical. No two individuals were found attached. It was at first thought that this might not be a diatom but close study of many individuals has convinced me that it is. It lacks any semblance of the structure of Radiolaria and Silicoflagellata but the markings on the globular portion are not greatly different from those on some Liradiscus.^^'' Odontotropis galeonis Hanna, new species Plate 4, figures i, 2, 3 Frustule with unequal valves, the superior one bearing two mast-like spines situated some distance from each end; outline boat-shaped, a sharp carina around the margin of the superior valve; the spines are on a sharp median carina on each side of which there are numerous beads ; inferior valve with two terminal spines the outline between being concave. Holotype: No. 2026; paratypes: Nos. 2027, 2028. Mus. Calif. Acad. Sci. from Moreno Gulch, Fresno County, California; upper Cretaceous. This species is abundant in the Moreno Shale and is not subject to much variation. It obviously belongs to Odontotropis Grunow, =""» Additional specimens from another locality, mounted after this report was in press, have branches or a bulbous growth at the tip of the "spine". This structure is not preserved in the holotype but shows the relationship of the genus with Pterotheca. Vol. XIII] HAHHA— CRETACEOUS DIATOMS 27 but has little in common with the species which have been de- scribed and which I have been able to find ; O. vitrea Pantocsek^^ is similarly formed but has an exceedingly high median keel on the superior valve. Through the kindness of Dr. Albert Mann I have had an oppor- tunity to examine specimens of 0. cristata Grunow from Mors, Jutland. The median carina surrounds the f rustule and bears long spines, like teeth in a comb. Most important, however, are the radial rows of close-set, minute beads on each valve. These are totally lacking in the Moreno material. I have also seen specimens of 0. birostrata Pantocsek and these lack the comb-like teeth of cristata on a carina and are heavily marked with wavy, anastomos- ing lines of silica on the superior valve, like a Liradiscus; the in- ferior valve is hyaline. The scattered spines on galeonis appear to be a constant and distinctive feature. 19. Pseudopyxilla russica (Pantocsek) Plate 4, figure 4 Pyxilla russica Pantocsek, Beit. Kennt. Foss. Bac. Ungarns, pt. 3, 1893, pi. 19, fig. 277 ; Kusnetzk, Russia. Pyxilla rossica Pantocsek, Op. cit. text, 1905, p. 91. Pseudopyxilla rossica (Pantocsek), Forti Studi per una Monografia del Genere Pyxilla (Diatomee) e dei generi affini. Nuova Notar- isia, Vol. 20, 1909, p. 28, pi. I, fig. 13. The specimens I have from the Moreno Shale agree in size and shape with the species named by Pantocsek as above. He spelled the name russica in the explanation of his plate, issued in 1893 ; presumably the spelling found in the text was a typographical error; at any rate, preference is given to the earliest published one. It is true, the California specimens do not seem to have a trace of the granulation shown near the apex of russica in Pantocsek's drawing and this might be considered grounds for specific separation in some groups of diatoms but is hardly suffi- cient in Pyxilla. Forti has reproduced figures of specimens from Richmond, Virginia, which likewise are apparently smooth so that it seems likely that the minute dots in Pantocsek's drawing may =" Beit. Kennt. Foss. Bac. Ungarns, pt. 3, p. 86, 1905, pi. 38, fig. 535, 1893. 28 CALIPOKHIA ACADEMY OF SCIEHCES [Oo. Papbm have been placed there for the purpose of shading rather than to indicate structure. The genus Pseudopyxilla was established by Forti in 1909 (see above reference) to contain various members of the heterogenous Pyxilla of Greville. He included under the name, 13 separate species in the following order : directa Pantocsek tempereana Forti, n. sp. lunyacseckii Pantocsek obliquepileata Forti, n. sp. americana Ehrenberg capreolus Forti, n. sp. hungarica Pantocsek baltica Grunow dubia Grunow rossica Pantocsek capreolus gracilior Forti, n. sp. vasta Pantocsek peragallorum Forti, n. sp. No type species was selected, and it would seem that the one described as " Rhizosolenia americana" by Ehrenberg, the best known as well as the oldest name, cannot be so recognized. The name "americana" will probably have to be associated with "Rhiz- osolenia" in some way in order to validate this well known name in accordance with the rules of nomenclature. I prefer to leave the problem open until all phases of it can be considered. Under the name, R. americana, Ehrenberg^^ gave nine figures. Forti has selected those diatoms with a branching spine at the apex to rep- resent the species, these being b, c, d, e, and / of Ehrenberg's figure. His a, h, and i, are smooth and have rounded apices; these, Forti would seemingly refer to the name russica and his classification in this respect seems entirely satisfactory. 20. Pseudostictodiscus pious Hanna, new species Plate 3, figures i, 2, 3, 4 Valve almost circular; walls turn sharply downward a very short distance leaving no hyaline border; center with a large circular hyaline area; rows of heavy beads radiate from this to the edge; almost half way from central area to margin there is, what appears under moderate magnification to be a heavy circular line of silica, apparently on the lower side, which produces a dark ■■=» Mikrogeologie, 1854, pi. 18, fig. 98, a-i. Vol. Xni] HAHHA— CRETACEOUS DIATOMS 29 ring. High magnification shows a bending down on the surface at this ring. Diameter, holotype, .0251 mm. ; paratype, .0268 mm. ; asymmetrical paratype, .0312 mm. Holotype: No. 2011; paratypes, 2012, 2013, 2014, Mus. CaHf. Acad. Sci. from Moreno Gulch, Fresno County, California; upper Cretaceous. This rather unobstructive diatom possesses characters which make it impossible to align it with any commonly recognized group. It is common in the samples which have been searched. The central hyaUne area is not always as broad as in the type specimen and in rare instances is almost completely dotted over. It appears that Grunow had in mind the species eulensteinii as a representative of his group Pseudostictodiscus because that is the only one mentioned when he first used the genus-name.^" Schmidt, however, in 1882^° had already used the name for the species angulatus Grunow, described by Kitton in 187P^ from Jutland Cretaceous ( ?) and apparently an abundant form in the Cretaceous ( ?) of Simbirsk, Russia. Schmidt's remarks at the bottom of his plate 75 (1882) are very significant in this con- nection : "The genus Triceratium requires fundamental revision which Grunow has in view. He wanted to place many figures of the plate [plate 75 on which eulensteinii appears] for the present in Pseudostictodiscus. I was glad to accept this new genus as Pseudost. angulatus but such forms as plate 75, figs. I, 2, 6, 7 and others I would not like to classify with plate 74, fig. 24 for fear of new complications. I have therefore left them under Triceratium." ^" Van Heurck accepted the name as Grunow evidently intended it to be used and cited only the species eulensteinii under it.^^ He put the group under Biddvdphia as a subgenus. I think the rules of nomenclature in botany will require the ac- ceptance of Schmidt's interpretation of the name Pseudostictodis- cus because of priority and angulatus must be considered the type species. -» Diat. Franz Josefs-Land. Denk. Math. Natur. Classe Kais. Akad. Wiss. Wien, Vol. 48, 18cS4, p. 18. "Atlas Diat. pi. 74, 1882, figs. 24-30. "Tourn. Quekett Micr. Club, Vol. 2, 1871, p. 168, pi. 13, figs. 1, 2. ^- Preston, nis. translation in C. A. S. library. " Treatise on Diatomaceas, 1896, pp. 466, 468, fig. 203. 3Q CALIFORNIA ACADEMY OF SCIEHCES [Oc. Papers The form described above from Moreno Gulch is certainly congeneric with angulatus and I have therefore put it under Pseudostictodiscus. The two are closely related but apparently entirely distinct and they do not seem to be sufficiently close to Stictodiscus to be accepted in that group. The species, eulensteinii, however, is very probably a Stictodiscus, and, being the type species of Grunow's Pseudostictodiscus, it will cause the latter to fall into synonymy. The data, briefly summarized, are as follows : Pseudostictodiscus Schmidt, Atlas Diat. pi. 74, 1882; type species: Stictodiscus angulatus Grunow in Kitton, Journ. Quekett Micr. Club, Vol. 2, 1871, p. 168, pi. 13, figs. I, 2; Jutland Cretaceous (?). The genus-name is considered valid. Pseudostictodiscus Grunow, Diat. Franz Josefs-Land. Denk. Math. Natur. Classe Kais. Akad. Wiss. Wien, Vol. 48, 1884, p. 18 ; type species : Pseudostictodiscus eulensteinii Grunow, op. cit. nomen nudum; =^Triceratium eulensteinii Grunow in Schmidt, Atlas Diat. pi. 75, 1882, figs. 6, 7 Nankoori living. The group name considered synonymous with Stictodiscus, Biddulphia or Triceratium. I do not favor the resurrection of genera from the bone yard of forgotten names when such action necessitates any considerable shifting of species. However, as in the present case, when a little used genus-name can be strictly applied in accordance with rules of nomenclature and thus avoid the making of a new one, it seems to be the preferred procedure. 21. Pterotheca crucifera Hanna, new species Plate 4, figure 5 Frustule circular in cross section; girdle area hyaline and cylindrical ; immediately above, the valve is roundly conical with about 10 coarse, siliceous ridges extending from the margin to the apex ; interspaces hyaline ; apex crowned with a huge spine apparently square in shape and with sharp keels on each corner, these keels extending down over the conical portion a short distance; near the top of the spine two heavy side, wing-like projections are developed on the spine. Diameter, .02 mm. Vol. XIII] HAHXA— CRETACEOUS DIATOMS 3 J Holotype: No. 2030, Mus. Calif. Acad. Sci. from Moreno Gulch, Fresno County, California; upper Cretaceous. This abundant species is similar to P. aculeifera Grunow^* and kittoniana Grunow, the latter being the type of the genus, but the Moreno form is shorter and has much heavier radiating ridges. In all of those seen the characters are very constant and, there being no approach to the Jutland forms, it seems best to keep them specifically distinct. 22. Pterotheca evermanni Hanna, new species Plate 4, figure 6 Frustule circular in cross-section, cylindrical, hyaline through- out; walls thick and heavy; end bearing a huge spine, on the upper-end of which there are several irregular branches ; the length of each valve varies considerably in proportion to diameter and the arrangement of the branch spines is not uniform but in all which have been seen the branching portion is about the same distance from the tip of the spine ; the spine is bent slightly away from the axis. Diameter, .02 mm. Syntypes: Nos. 2031, 2032, 2033, Mus. Calif. Acad. Sci. from Moreno Gulch, Fresno County, California; upper Cretaceous. Pterotheca was established by Grunow in 1880^^ for the species, kittoniana from the Jutland deposit,^® and Van Heurck (1896) considered the group entitled to no greater than subgeneric rank under Pyxilla. Forti, in 1909,^^ however, recognized the distinct- ness of the group and I agree that it should be separated from Pyxilla. Sphynctolethus Hanna, new genus Diatom, small, biddulphoid, ovate, deep; finely marked with radial rows of beads throughout; general shape of valve so un- usual and irregular as to be almost indescribable without pictures. Genotype : Sphynctolethus monstrosus, new species. " See Van Heurck, Treatise on Diatomacese, 1896, p. 430, fig. 151. ''In Van Heurck, Syn. Diat. Belgique, pi. 83 ter 1880, figs. 10-11. ^ Kitton had previously figured this form as "Goniothecium" ? but did not give it a specific name. »' Nuova Notarisia, Vol. 20, 1909, pp. 19-38. 32 CALIFORNIA ACADEMY OF SCIEHCES [Oc. Papers 23. Sphynctolethus monstrosus Hanna, new species Plate 4, figures 7, 8 Valve ovate, biddulphoid, very deep in vertical dimension ; com- posed of three parts; the central ovate portion has sloping sides and passes upward into a middle more or less quadrangular por- tion with rounded edges and placed across the shorter diameter of the valve; the outer (upper) portion is again ovate with a pe- culiarly shaped horn at each end of the long diameter; between the horns and central area, there are depressions to the level of the central portion; valve finely marked with radiating rows of beads throughout. Long diameter, .070 mm. ; short diameter, .0534 mm.; total height, .0155 mm. Holotype: No. 2034, Mus. Calif. Acad. Sci. from Moreno Gulch, Fresno County, California; upper Cretaceous. This remarkable diatom has no close relative that I can find in the literature. It is obviously biddulphoid but differs so greatly from Biddulphia and allied genera that it would be inconsistent to place it in any of them. The only one at all closely related appears to be Cheloniodiscus Pantocsek, 1889^^ from the Cretace- ous of northern Russia but the differences are so pronounced that the union of the two seems impossible. On account of its depth it is difficult to photograph with one view but it is believed that with the structural drawings herewith, its form will be under- stood properly. The type specimen shown in the photograph is imperfect but displays all of the specific and generic characters. It appeared to be rare in the samples studied but this may have been due to the fragile nature of the frustule. Fragments were not uncommon. 24. Stephanopyxis appendiculata (Ehrenberg) Plate 4, figure g Pyxidicula appendiculata Ehrenberg, Ber. Akad. Wiss. Berl. 1844, pp. 85, 264. Stephanopyxis appendiculata (Ehrenberg), Mikrogeologie, 1854, pi. 18, fig. 4- — Schmidt, Atlas Diat. pi. 130, 1888, figs. 18-26.— Stephano- pyxis appendicula (Ehr.) Mann, Cont. U. S. Nat. Herb. Vol. 10, No. 5, 1907, p. 244. "" See Van Heurck, Treatise on Diatomaceae, 1896, p. 541. Vol. XIII] HAHHA— CRETACEOUS DIATOMS 33 This Species is very common through a considerable vertical range in the Moreno Shale. Various modifications of the species have received subspecific names and others have been considered separate species but, as Dr. Mann has pointed out, variation among individuals in the same chain or even between the two valves of the same individual, is so great that considerable lati- tude must be taken in establishing division lines of species. This appears to be the only species found in the Moreno Cretaceous which is still living. 25. Stephanopyxis discrepans Hanna, new species Plate 4, figures lO, 11 Valve circular, slightly convex, flat inside the annular row of spines; spines (in holotype) set in a row just inside border as in Cyclotella but this character is not constant; other specimens have the spines far toward the center of the valve ; markings consist of coarse, irregularly shaped beads arranged in no regular order ; in this respect the species differs from all other Stephanopyxis known to me with the exception of 5. nidulus Brun^** from the fossil deposit at Sendai, Japan ; the Japanese species has much longer and much more regularly spaced spines and smaller mark- ings. Diameter, holotype, .0394 mm. ; paratype, .0186 mm, Holotype: No. 2036; paratype No. 2037. Mus. Calif. Acad. Sci. from Moreno Gulch, Fresno County, California; upper Cretaceous. This is an abundant and very characteristic species in all of the samples of Moreno Shale examined. It is not as convex as most Stephanopyxis but there does not appear to be a genus in which it can be better placed. 26. Stephanopyxis grunowi Grove & Sturt Plate 4, figure 12 Stephanopyxis grunowi Grove & Sturt, Schmidt, Atlas Diat. pi. 130, 1888, figs. 1-5 ; Oamaru, New Zealand. »» Schmidt, Atlas Diat. pi. 164, 1891, figs. 7, 8. September 17, 1927 34 CALIFORHIA ACADEMY OF SCIENCES [Oc. Papers This large and handsome species is probably the most common diatom in the Moreno Cretaceous deposit. It did not reach the huge size that it did during the Monterey Miocene in California but otherwise it does not appear to differ to any noteworthy ex- tent. The development of spines is very erratic, the specimen figured being without, but in others they are as large and variable in number and size as Schmidt has shown. The species was originally described from the deposit at Oamaru, New Zealand, which has been referred to various geologic ages from Oligocene to Cretaceous. Also it has been recorded from California Miocene strata at least twice.*" 27. Triceratium bicornigerum Hanna, new species Plate 4, figures 13, 14 Valve with two horns only, semi-eliptical ; horns finely marked with beading, but little elevated above the plane of the valve ; sur- face marked with heavy, irregularly scattered beads, there being a suggestion of radial arrangement about the excentrically placed "apex"; apex nearer the convex than the straight side; sides bent downward at the margin, straight or expanded, and marked as the surface. Length of straight side, .0590 mm. ; (holotype). Holotype: No. 2039; paratype, No. 2040, Mus. Calif. Acad. Sci. from Moreno Gulch, Fresno County, California; upper Cretaceous. This is one of the most abundant diatoms in this Cretaceous deposit and is subject to little variation. Among the hundreds of examples which passed under critical study not one showed the slightest tendency to develop a third angle. It, therefore, cannot be considered to be a sporadic form or a species, normally trigonal or polygonal. In the literature I find a somewhat similar species described from the Miocene deposits of the eastern United States as Tri- ceratium semicirculare Brightwell. 41 "Schultze & Kain, Bull. Torrey Bot. Club, Vol. 23, 1896, p. 502; Santa Monica.— Mann in Jordan, Stanford Univ. Publ. Univ. Ser. Biol. Sci. Vol. 1, No. 4, 1921, p. 295; Lompoc. "See Kain & Schultze, Bull. Torrey Bot. Club, Vol. 16, 1889, p. 76, pi. 89, figs. 6, 6a. Vol. XIII] HANNA— CRETACEOUS DIATOMS 35 When the final analysis is made of biddulphoid diatoms it is probable that these two forms will fall in a different generic group from Triceratiiim, Trigonium, Trinacra or Biddulphia, but the present state of nomenclature does not warrant a segregation. Therefore, I have placed the Cretaceous species under the old, unnatural group, Triceratium. 28. Triceratium hertleini Hanna, new species Plate 4, figure 15 Triangular with sides strongly rounded ; at each corner a short blunt spine scarcely higher than surface of valve; margin heavy and uniformly thick ; surface divided by markings into two zones, the outer being coarsely beaded and somewhat higher than the inner, almost circular zone ; the latter contains a very few coarse beads. Length of one side, .0441 mm. Holotype: No. 2041, Mus. Calif. Acad. Sci. from Moreno Gulch, Fresno County, California; upper Cretaceous. The species, although small, is very striking due to the coarse beading. The corner-spines are obscure and it appears to be a sort of intergrade with some forms of Stictodiscus. Except for the three spines not being placed inward from the margin and its more angular outline, the species resembles Aulaco- discus schmidtii Witt,*^ from Archangelsk, Russia, or what ap- pears to be the same and under an earlier name, A. septus Schmidt*^ from Simbirsk. The two (or three) species, together certainly appear to form connecting links between Aulacodiscus, Stictodiscus and Triceratium. It does not seem possible at this time to untangle the nomen- clature assembled about the old genus Triceratium and properly place many species until a study will have been made of the vari- ous genotypes. Therefore, I feel obliged, regretfully, to refer the present form to that name. «Verh. Russ. Kais. Mineral, Gesell. St. Petersburg, Ser. 2, Vol. 22, 1886, p. 157, pi. 7, fig. 12— Schmidt, Atlas Diat. pi. 101, 1886,^ figs. 1-3. «» Atlas Diat. pi. 36, 1876, figs. 19-21. 36 CALIFOKHIA ACADEMY OF SCIEHCES [Oc. Papehs The species is named for Mr. Leo G. Hertlein, of the Depart- ment of Paleontology of the Academy. 29. Trinacria aries Witt Plate 5, figures i, 2 Trinacria aries Witt in Schmidt, Atlas Diat. pi. 150, 1890, figs. 14, 15; Archangelsk, Russia. This exceedingly, heavily beaded form, shaped like T. excavata, is very common in the Moreno Cretaceous material. The smaller ones are especially numerous in the finer washings but the larger forms are usually more or less broken when found, due to the violent treatment necessary to disintegrate these rocks. 30. Trinacria deciusi Hanna, new species Plate 5, figures 3, 4, 5 Triangular, sides gently concave, corners rounded; edges straight, heavily beaded ; central area hexagonal with sides almost equal in length and with a few rows of roughly radial, very heavy beads; these beads are lacking in the very center; corner com- partments or horns slightly raised above level of central area, flat on top and heavily beaded ; between central area and corner com- partments, internal septse are developed which photograph black. Length of sides of two syntypes, .0250 mm. and .0195 mm. Syntypes: Nos. 2044, 2045; paratype: No. 2046, Mus. Calif. Acad. Sci. from Moreno Gulch, Fresno County, California; upper Cretaceous. This minute Trinacria is abundant at the Moreno locality and its characters are very constant, thus contrasting notably with other species of the genus. It is named for Mr. L. C. Decius of San Francisco, who has been associated with the writer in many geological investigations. Vol. XIII] HAHHA— CRETACEOUS DIATOMS 37 31. Trinacria excavata Heiberg Plate 5, figure 6 Trinacria excavata Heiberg, Conspectus Criticus Diatomacearum Dani- cum, 1863, p. 51, pi. 4, fig. 9.— Schmidt, Atlas, Diat. pi. 97, 1886, figs. 6, 7, (not figs. 8-10 = T. pileola Ehrenberg.) Individual diatoms which resemble Schmidt's figure cited above, are rare in the Moreno Gulch, Cretaceous deposit. The original drawing of Heiberg has not been seen. The specimen figured -'^^C; nV">'"- measures .0589 mm. on one side. / VV^"> "^x < 32. Trinacria insipiens Witt \h.l'w^ ^ ^ Plate 5, figures 7, 8, g Trinacria insipiens Witt, Verb. Russ. Kais. Mineral. Gesell. St. Petersburg, Ser. 2, Vol. 22, i886, p. 172, pi. 10, fig. i; pi. 11, figs. 5, 7, 11; pi. 12, fig. 2; Archangelsk, Simbirsk. — Schmidt, Atlas Diat. pi. 97, 1886, fig. 16. Trinacria pileolus Ehrenberg, Witt, Op. cit. p. 172, pi. 9, fig. 15 ; pi. 10, fig. 4; pi. II, figs. 6, 9. — Schmidt, Atlas Diat. pi. 97, 1886, figs. 19, 20; pi. Ill, figs. 8-13. Not Triceratium pileolus Ehrenberg, Mikrog. 1854, pi. 35A, group 21, fig. 17, from Antarctic ice floes. The diatoms which have been referred to this species cor- respond to the original figures of Witt, particularly the one he called "var. intermedia." It is quite certain that too many names have been given to this protean Cretaceous species and I cannot agree to the reference of some of the forms to the living pileolus of Ehrenberg from the Antarctic ice floes. His figure in the Mikrogeologie may as well be interpreted to be a cellular form without raised horns as a beaded form with long projections at the three corners. Rather than refer the well figured fossil forms to such an uncertain picture it seems much better to hold them distinct and under a name which seems to be the proper one for them. Great variation is displayed among the many individuals examined in the course of this study and it is believed that all the variants are properly considered to be merely one species. 33 CALIFOKHIA ACADEMY OF SCIEHCES [Oc. Papers 33. Trinacria mucronata (Schmidt) Plate 5, figure lo Triceratium mucronatum Schmidt, Atlas Diat. pi. iii, i886, figs, i, 2. "Archangelsk, Russia". This large and handsome species, as Schmidt remarked, differs from T. grevillei in the complete absence of horns or spurs at the corners. The beading is likewise finer in the specimens I have seen. It is common in the Moreno Cretaceous deposits of California and reaches a length on one side of .0890 mm. The species is thus sometimes much larger than the protean T. insipiens of the same deposit. Nevertheless, in a large series, there appears to be inter- grading forms between these two species and the largest one shown herewith as T. insipiens might have been referred to T. mucronata just as well. In view of this situation, the mere ab- sence of horns does not seem good reason for removing mucronata from Trinacria as Schmidt did. 34. Trinacria tristictia Hanna, new species Plate 5, figures ii, 12 Triangular with side walls deep and heavily beaded; corners sharp, elevated in triangular protuberances to practically the same height as the center of the disk; between these protuberances (or horns ) and the central area, there is a rectangular depressed zone ; central area blank or with very sparse beads ; rest of upper sur- faces including flat topped horns, with radiating rows of fairly heavy beads. Length of one side, holotype, .0566 mm. Holotype: No. 2052; paratype: No. 2053, Mus. Calif. Acad. Sci. from Moreno Gulch, Fresno County, California; upper Cretaceous. No diatom has been found in the literature which appears to be close to this species. It is common in the Moreno deposit and often there are black radiating lines on the disk; presumably these are caused by some factor in the preservation because they are so often absent. Vol. XIII] HAHHA— CRETACEOUS DIATOMS 39 35. Xanthiopyxis granti Hanna, new species Plate 5, figures 13, 14 Valve elongate ovate, rounded at the ends, slightly uneven on the sides, border very narrow ; surface covered with rather large beading with interspersed here and there a series of short sharp spines. Holotype: No. 2054; paratype: No. 2055, Mus. Calif. Acad. Sci. from Moreno Gulch, Fresno County, California; upper Cretaceous. The two specimens figured appear very unlike, but it is believed that they are the same ; the Moreno Shale contains such forms in abundance and in a large series, such as has been examined, there is much variation although the majority of individuals conform to the type in most respects. In noi case was a diatom seen which approaches in form and detail the familiar X. ohlonga of the Monterey Miocene. The species is named for Mr. W. M. Grant of San Francisco California. 40 CALIFORNIA ACADEMY OF SCIEHCES [Oc. Papem Plate I Fig. I. Actinoptychus packi, n. sp. Holotype, No. 1992, C. A. S. x 540; diameter, .0865 mm. Fig. 2. Actinoptychus packi, n. sp. Paratype, No. 1993, C. A. S. x 540; diameter, .0657 mm. Fig. 3. Actinoptychus packi, n. sp. Paratype, No. 1994, C. A. S. x 540; diameter, .0764 mm. Fig. 4. Actinoptychus taffi, n. sp. Holotype, No. 1995, C. A. S. x 840; diameter, .0656 mm. Fig. 5. Aulacodiscus cretaceus, n. sp. Holotype, No. 1996, C. A. S. x 400; diameter, .071 mm. Fig. 6. Aulacodiscus pugnalis, n. sp. Holotype, No. 1997, C. A. S. x 560; diameter, .104 mm. Fig. 7. • Aulacodiscus pugnalis, n. sp. Paratype, No. 1998, C. A. S. x 540; diameter, .103 mm. Fig. 8. Auliscus tenigmus, n. sp. Holotype, No. 1999, C. A. S. x 1080; greatest diameter, .0429 mm. Fig. 9. Benetorus fantasmus, n. sp. Holotype, No. 2000, C. A. S. x 800; diameter, .050 mm. Fig. 10. Benetorus fantasmus, n. sp. Paratype, No. 2001, C. A. S. x 800; diameter, .0528 mm. All diatoms illustrated on this plate are from the upper 320 feet of exposed upper Cretaceous shale on Moreno Gulch, Fresno County, California. Magnifications are only approximately correct but actual dimensions are micrometric measurements. OC. PAPERS, CAL. ACAD. SCI., Vol. Xlli [HANNA] Plate 1 September 17, 1927 ^it ^ « _j^7 CALIFORHIA ACADEMY OF SCIEHCES [Oc. Papers Plate 2 Fig. I. Cladu(/raiiiiiia jordani, n. sp. Holotypc, No. 2002, C. A. S. \ 1200; diameter, .0286 mm. Fig. 2. Cosciiiodisciis iiiimaciilattis, n. s]). FTolotype, No. 200.^, C. A. S. X 560 ; diameter, .0860 mm. Fig. 3. Cosciiiodiscus inorciiocusis, n. sji. ilolotyiie, No. 2004, C. A. S. X 200; diameter, .216 mm. Fig. 4. Cosciiiodisciis iitorciiociisis, 11. sp. i'aratyi)C, No. 2005, C. A. S. X 500; diameter, .0854 mm. Fig. 5. Cosciiiodiscits stciiiyi, n. s]). TTololype, No. 2006, C. A. S. x 400; diameter, .0908 mm. i'^ig. 6. Cosciiiodist'iis stciiiyi, n. s\). Hololype, No. 2006, C. A. S. x 400; diameter, .0908 mm. Figs. 5 and 6 are photographs of the same specimen, the latter being in the higher [ocns to show details of central area. Fig. 7. Glorioptyclms callidiis, n. sp. Flolotype, No. 2007, C. A. S. x 810; diameter, .0681 mm. Fig. 8. Glorioptyclms callidiis, n. sp. Flolotype, No. 2007, C. A. S. x 810; diameter, .0681 mm. Figs. 7 and 8 are pholograi)hs of the same specimen, the latter being with liie higher focus to show detail not depicted in fig. 7. Fig. 9. 1 [ciiiianliis polyiiiorpliiis Grnnow ; I'lesiotype, No. 2008, C. A. S. X 700 ; length, .052 mm. Fig. 10. I Iciniaulus polyiiiorplius Grunow; ]Mesiotyi)e, No. 2009, C. A. S. X 400; length, .071O mm. Fig. II. I lorodisciis iiiacroscriptus. n. s]). Holotype, No. 2010, C". A. S. x 1080; diameter, .0525 mm. All diatoms illustrated on this plate are from the upper 320 feet of exposed upper Cretaceous shale on Moreno Gulch, iM'esno County, California. Magnifications are only approximately correct, but actual dimensions are mici"ometric measurements. OC. PAPERS, CAL. ACAD. SCI., Vol. XIII [HANNA] Plate 2 6 .^ /■■■ ''-<-\- 44 CALIFORHIA ACADEMY OF SCIEHCES [Oc. Papers Plate 3 Fig. I. Fscttdostictodisctis pints, n. sp. Holotype, No. 201 1, C. A. S. x 1600; diameter, .0251 mm. Fig. 2. Fscudostictodisciis picits. 11. sp. Paratype, No. 2012, C. A. S. x 1200; diameter, .0286 mm. Fig. 3. F^sciidostiitodisnts pints, n. sp. Paratype, No. 2013, C. A. S. x 1400; diameter, .0312 mm.; a rare, asymmetrical form. Fig. 4. Psciidostirtodisnis piciis, n. sp. Paratype, No. 2014, C. A. S. x 700; diameter, .0291 mm.; a rare form with disk almost com- pletely dotted over. Fig. 5. Liradiscits oi'alis Greville ; Plesiotype, No. 2018, C. A. S. x 800; greatest diameter, .030 mm. Fig. 6. Ki'iitrodiscus aculeatus, n. sp. Holotype, No. 2015, C. A. S. x 740 ; diameter, .0336 mm. Fig. 7. Kciitrodiscits aiidcrsoni, n. sp. Holotype, No. 2016, C. A. S. x 1000 ; diameter, .0362 mm. Fig. 8. Kciitrodiscits aiidcrsoni, n. sp. Paratype, No. 2017, C. A. S. x 670; diameter, .040 mm.; basal view. Fig. 9. Mcrctrosulus gracilis, n. sp. Holotype, No. 2019, C. A. S. x 1600; length, .0309 mm. ; width, .0239 mm. Fig. 10. Mcrctrosulus gracilis, n. sp. Paratype, No. 2020, C. A. S. x 810; length, .0590 mm. Fig. II. Mclosira faiista Schmidt; Plesiotype, No. 2021, C. A. S. x 1000; diameter, .0348 mm. Fig. 12. Mclosira fausta Schmidt; Plesiotype, No. 2022, C. A. S. x 1000; diameter, .0340 mm. Fig. 13. Mclosira fausta Schmidt; Plesiotype, No. 2023, C. A. S. x 400; diameter, .0594 mm. V\^. 14. Mclosira fausta Schmidt; Plesiotype, No. 2024, C. A. S. x J200; diameter, .oi8r mm. Fig. 15. Micrainpitlla parvula, n. sp. Holotype, No. 2025, C. A. S. x 1200; diameter, .0087 mm. All diatoms illustrated on this plate are from the upper 320 feet of exposed upper Cretaceous shale on Moreno Gulch, Fresno County, California. Magnifications are only approximately correct, but actual dimensions are micrometric measurements. •^ ' '■fii / OC. PAPERS, CAL. ACAD. SCI., Vol. XIII [HANNAl Plate 3 45 CALIFORKIA ACADEMY OF SCIEHCES [Oc. Papers Plate 4 Fig. ]. Odoiitolrofis (lalconis, n. sp. Holotype, No. 2026, C. A. S. x 20V . length, .0926 mm.; side view of frustulc, somewhat lirokcn on right end. Fig. 2. Odontotropis (jalconis, n. sp. Paratype, No. 2027, C. A. S. x 200; length, .1054 mm.; upper valve, slightly inclined. Fig. 3. Odontotropis (jalcoiiis, n. sp. Paratype, No. 2028, C. A. S. x 540; length, .07:6 mm. ; side view of upper valve. Fig. 4. Pscudopyxilla nissica (Pantocsek) ; Plesiotype, No. 2029, C. A. S. X 910; length, .0339 mm.; width, .0198 mm. Fig. 5. Ptcrotheca crucifera, n. sp. Holotype, No. 2030, C. A. S. x 1200; diameter, .02 mm. Fig. 6. Ptcrotheca cvcnnaimi, n. sp. Syntype, No. 2031, C. A. S. x 750; diameter, .02. Fig. 7. Sphynctolcthus monstrosiis, n. sp. Holotype, No. 2034, C. A. S. X 700; length, .070 mm. Fig. 8. Spltynctolctlius monstrosus, n. sp. Holotype, No. 2034, C. A. S. drawing of side view and detail of horn. Fig. 9. Stcplianopyxis appciidiculata (Ehrenberg) ; Plesiotype, No. 2035, C. A. S. X 1200; diameter, .0283 mm.; outline drawing of side view of one valve. Fig. 10. Stcplianopyxis discrcpaiis, n. sp. Holotype, No. 2036, C. A. S. x 1400; diameter, .0394 mm.; side view of specimen shown at a. Fig. II. Stcplianopyxis discrcpans, n. sp. Paratype, No. 2037, C. A. S. x 1400 ; diameter, .0186 mm ; side view of specimen shown at a. Fig. 12. Stcplianopyxis gninowi Grove & Sturt ; Plesiotype, No. 2038, C. A. S. X 700; diameter, .050 mm. Fig. 13. Triccratiuni biconiigcrmii, n. sp. Holotype, No. 2039, C. A. S. x 800; length of straight side, .0590 mm. Ing. 14. Triccratiuni hicornigcrum, n. sp. Paratyi)e, No. 2040, C. A. S. x 800; length of straight side, .0454 mm. Fig. 15. Triccratiuni hcrtlcini, n. sp. Holotype, No. 2041, C. A. S. x 800; length of one side, .0441 mm. All diatoms illustrated on this plate are from the upper 320 feet of exposed upper Cretaceous shale on Moreno Gulch, Fresno County, California. Magnifications are only approximately correct, Init actual dimensions are micrometric measurements. OC. PAPERS, CAL. ACAD. SCI., Vol. XIII [HANNAI Plate 4 4g CALIFORKIA ACADEMY OF SCIEHCES [Oc. Papers Plate 5 Fig. T. Trinacria aries Witt; Plesiotype, No. 2042, C. A. S. x 1200; length of one side, .042T mm. Fig. 2. Trinacria aries Witt; I'lesiotype, No. 2043, C. A. S. x 1200; length of one side, .0385 mm. Fig. 3. Trinacria deciusi, n. sp. Syntype, No. 2044, C. A. S. x 1080; length of one side, .0250 mm. ]'"ig. 4. Trinacria deciusi, n. sp. Syntype, No. 2045, C. A. S. x 1500; length of one side, .0195 mm. ; side view showing raised corners. Fig. 5. Trinacria deciusi, n. sp. Paratype, No. 2046, C. A. S. x 1600 ; length of one side, .0287 mm. Fig. 6. Trinacria excavata, Heiberg; Plesiotype, No. 2047, C. A. S. x 840; length of one side, .0589 mm. Fig. 7. Trinacria iiisipicns Witt; Plesiotype, No. 2048, C. A. S. x 800; length of one side, .0474 mm. Fig. 8. Trinacria insipiens Witt; Plesiotype, No. 2049, C. A. S. x 800; length of one side, .0383 mm. Fig. 9. Trinacria insipiens Witt; Plesiotype, No. 2050, C. A. S. x 1600; length of one side, .0242 mm. Fig. 10. Trinacria niitcronata (Schmidt); Plesiotype, No. 2051, C. A. S. X 560; length of one side, .0890 mm. Fig. II. Trinacria iristictia, n. sp. Holotype, No. 2052, C. A. S. x 800; length of one side, .05O6 mm. Fig. 12. Trinacria tristicfia, n. sp. Paratype, No. 2053, C. A. S. x 810; length of one side, .040 mm. Fig. 13. Xantliiopyxis granii, n. sp. Holotype, No. 2054, C. A. S. x 400; length, .0756 mm. Fig. 14. Xantliiopyxis granti, n. sp. Paratype, No. 2055, C. A. S. x 1200; length, .040 mm. All diatoms illustrated on this plate are from the upper 320 feet of exposed upper Cretaceous shale on Moreno Gulch, Fresno County, California. Magnifications are only approximately correct, but actual dimensions are micrometric measurements. OC. PAPERS, CAL. ACAD. SCI., Vol. XII [HANNAJ Plate 5 V Occasional Papers OF THE CALIFORNIA ACADEMY OF SCIENCES XIII SAN FRANCISCO Published by the Academy September 17, 1927 COMMITTEE ON PUBLICATION George C. Edwards, Chairman C. E. Grunsky Barton Warren Evermann, Editor MBL/WHOI LIBRARY UH 1 Ft3