154 CALIFORNIA ACADEMY OF SCIENCES (Occ. Papers Collaboration with the scientific authorities is especially important and it will be a great accomplishment indeed when young Ecuadorian scientists study together with foreign specialists in our Station, a real international crossroad. Moreover, we hope that the Ecuadorian government will consult with the Foundation in matters concerning the conservation of nature in Galapagos. All legal measures must be taken by Ecuador, for it is not our intention to in- terfere in any manner whatsoever with its sovereignty. Weare willing, however, to answer official requests for advice, on the basis of scientific investiga- tions made under Foundation auspices. Our Foundation is probably unique in its class. It is an international institution whose aim is to advance our scientific knowledge specifically in the Galapagos region and to conserve the remarkable biota inhabiting it. The evolutionary theories of Charles Darwin, which belong to mankind as a whole, completely justify such an organization. On the other hand, the invaluable natural inheritance of Galapagos wildlife was threatened by men of all nation- alities; it is logical, therefore, that scientists and conservationists from all nations collaborate with the Ecuadorians to study and save what is left of these islands for the benefit of generations to come. OCCASIONAL PAPERS OF THE California Academy of Sciences No. 45, 27 pages, 5 plates. July 1, 1964 SOME FOSSIL DIATOMS FROM BARBADOS By G Dallas Hanna California Academy of Sciences and A. L. Brigger Yucaipa, California n^^iine Biological Laboratory L-IBRARY \ JUL 1 31964 WOODS HOLE, MASS. SAN FRANCISCO PUBLISHED BY THE ACADEMY 1964 OCCASIONAL PAPERS OF THE CALIFORNIA ACADEMY OF SCIENCES No. 45, 27 pages, 5 plates. July 1, 1964 SOME FOSSIL DIATOMS FROM BARBADOS By G Dallas Hanna California Academy of Sciences and A. L. Brigger Yucaipa, California The island of Barbados has attracted the attention of geologists and paleontologists for many years because of the existence there of a thick ser- ies of marine sediments known as the "Oceanic beds" or lately the "Oceanic formation." This name was selected because of the presence of Radiolaria in large numbers at several localities. The abundance of these organisms was thought to indicate deep water or "oceanic" deposition, a conclusion, how- ever, which does not necessarily follow. A very extensive literature exists on the geology of the island. No at- tempt will be made here to review it but reference to a few important titles seems necessary. The first extensive history of the island was by Schomburgh (1847) and the first description of the geology in detail was by Jukes-Browne and Harrison (1891, 1892). Schuchert (1935) gave an extensive account of the interrelationships of the various Caribbean islands and lately there have ap- peared numerous papers on various aspects of the geology of Barbados. Thus Senn (1940) discussed the various formations exposed on the island together with age determinations. He also gave the bases for the age determinations assigned and a bibliography of 95 titles. The Oceanic formation was believed, on good paleontological evidence derived from Foraminifera, to be of upper Eocene and lower Oligocene age. 2 CALIFORNIA ACADEMY OF SCIENCES (Occ. Papers Strange to say, geologists have given almost no notice to the extensive literature on the diatoms and radiolarians which have been described from these early Tertiary sediments. In fact, it would seem from the review made in connection with the present paper that the existence of this paleontologi- cal literature was unknown. Ehrenberg did much work on the Radiolaria of Barbados material and published extensive papers. The last one (1875 [T876]) contains a recapitula- tion of his studies and 30 plates with illustrations of over 200 species of these siliceous organisms. More than 100 species of diatoms have been found in the sediments and these are scattered through scores of publications. The importance of the de- posits from this standpoint was first brought out through the publications of R. K. Greville (1861-1866). Some of his material was furnished to him by other diatomists but he described and illustrated the species in a series of 20 pa- pers numbered serially and entitled: "Descriptions of new and rare diatoms." The Barbados species were included with others from various localities. Most of Greville's species and a very large number of additional ones have been described subsequently by many authors. This followed because of the rarity of early Tertiary diatoms and the demand for material by microscopists from near and far. Unfortunately, early collectors of such materials did not keep very accurate records of localities, certainly not sufficiently exact to serve the needs of modern geologists. And apparently not knowing of the existence of the published records, geologists of late have had no incentive to try to determine where the original collections were obtained. There are several papers which are based entirely or almost entirely on Barbados diatom material. Greville (1862) published a paper "On the Astero- lamprae of the Barbados deposit." Payne (1922) wrote a long account of Lio- stephania which certainly bears some resemblance to Asterolampra. Bergon (1892) monographed the genus Entogonia which is largely confined to the Bar- bados deposits. And the most beautiful illustrations of Barbados diatoms are those of Laporte and Lefebure (1929, 1930). The late J. H. Robinson devoted much time and labor in an effort to re- locate some of the famous localities on the island. As a result he published four papers (1934-1937) in the Journal of the Barbados Museum and Historical Society in which he described some of the localities in detail. In three of these papers he gave long lists of species which had been identified from his sam- ples. Some of the identifications were by Robert Hagelstein and others by Frederick Adams. The material upon which the present study is based was provided by Mr. Robinson. The sample which furnished the best preserved specimens came from "Joe's River," a locality which has not previously appeared in diatom literature to any great extent. This maybe the chief reason why some unde- No. 45) HANNA & BRIGGER: FOSSIL DIATOMS FROM BARBADOS 3 scribed species were found although many hours of search was a contributing factor. In 1958 easier published a paper on the fossil fishes of Barbados and Trinidad islands. In this he gave a table of formations on Barbados, adapted in large part from Senn (1940, pp. 1578-1582). This table shows the "Joe's River clays" to be upper Eocene in age. The sediments immediately below this are referred to the "Scotland formation" which contains some names more or less familiar to diatomists. Thus, here we have "Chalky Mount," "Mount Hillaby,"etc. Sediments below the Scotland formation are referred to as "from above Cambridge," but whether this has any bearing on the location of the fa- mous "Cambridge Estate" diatom locality is not certain. Descriptions and Notes on Species Actinoptychus hillabyanus Brun. (Plate 1, figures 1, 2.) Frustule circular with a narrow marginal band; each valve divided into six segments, adjacent ones differing in elevation only slightly; each segment has a very small nodule in the center at the margin and with a short radial blank line. One valve has descrete beads closely set in the marginal area but thinning toward a large blank central area, the beads being arranged in ran- dom order. The other valve is much more densely covered with the same size of beads; these are arranged in diagonal rows from the center of each segment the central blank area is smaller on this valve than on the other. Diameter, .116 mm. HOLOTYPE (two valves of same frustule) no. 3508 (Calif. Acad. Sci., Geol. Dept. Type Coll.) from Joe's River, Barbados, West Indies. Eocene. It is not often that the two valves of a single frustule of a fossil diatom can be obtained with certainty and in this case it is noteworthy that they are quite different. Brun described this species from Barbados (1896, p. 230) and his illus- trations do not differ significantly from ours. There does not seem to be a trace of secondary structure such as appears so frequently in members of the genus Actinoptychus. Aulacodiscus behani Hanna and Brigger, new species (Plate 1, figure 6.) Valve circular with five robust, blunt, conical spines; spaces between the spines slightly depressed, .0015 mm. Surface marked with fine irregularly 4 CALIFORNIA ACADEMY OF SCIENCES (Occ. Papers spaced bars producing a blotchy appearance between the spines but having a radial arrangement in the center. Most of these bars can be resolved into fine dots with sufficient magnification, aperture, and oblique light. Diameter, .0756 mm. HoLOTYPE no. 3509 (Calif. Acad. Sci., Geol. Dept. Type Coll.), from Joe's River, Barbados, West Indies. Eocene. The species is named for the late Richard N. Behan of San Francisco, who assembled a considerable collection of diatoms which is now a part of the collection of the California Academy of Sciences. Aulacodiscus currus Hanna and Brigger, new species. (Plate 1, figure 5.) Valve circular with five blunt spines set in large ocelli-like spaces; from each of these marginal spines a blank space extends radially inward to a small blank central area; surface covered with closely spaced small round dots arranged in radial rows; these are interrupted a little more than a third of the way to the center by a narrow clear circle with dots heavier along it. Diameter, .0914 mm. HOLOTYPE no. 3510 (Calif. Acad. Sci., Geol. Dept. Type Coll.) from Con- set, Barbados, West Indies. Eocene. The inner conspicuous circle, set as if to reinforce the spokes of a wheel, seems to set this diatom apart from other Aulacodiscus. Aulacodiscus angulatus Greville. (Plate 1, figure 3; plate 5, figure 7.) This beautiful diatom usually has five spines with a sharp radial ridge extending from each toward but not to the center. The spines are low, .004 mm. high. Spaces between the radial ridges are gently concave but on the whole the disk is relatively flat. Markings consist of discrete radial rows of beads with the central circular area set apart and with a small blank area in the cen- ter. Diameter (pi. 1, fig. 3), .117 mm. Hypotypes nos. 3511, 3512 (Calif. Acad. Sci., Geol. Dept. Type Coll.), from Joe's River, Barbados, West Indies. Eocene. Another specimen in the collection from the same locality has the spaces between the radial ridges more deeply concave and the size of the beads is slightly smaller than in the one described above. No. 45) HANNA & BRIGGER: FOSSIL DIATOMS FROM BARBADOS 5 Laporte and Lefebure (1929) illustrated a specimen, which may be this diatom, from Oamaru, New Zealand. It has only four radial ridges and the one on our plate 5 has six. Aulacodiscus hirtus Barker and Meakin. (Plate 2, figure 1.) Aulacodiscus hirtus BARKER AND MEAKIN, 19??- Journ. Quekett Micr. Club, ser. 4, vol. 2, no. 6, p. 301, pi. 37, fig. 1. SCHMIDT, 1874. Atlas Diat., pi. 461, figs. 3, 4 (issued 1958). This species was originally described from material which came from Kamischev, U.S.S.R. It is very similar to A. jutlandicus Kitton from the Pale- ocene of Denmark, as drawn by Schmidt (Atlas Diat. pi. 41, fig. 5). The diffi- ficulties involved in making an accurate drawing of one of these objects has influenced us in choosing the name hirtus because it is well illustrated with a photograph. Hypotype no. 3534 (Calif. Acad. Sci., Geol. Dept. Type Coll.), Joe's River, Barbados, West Indies. Eocene. Aulacodiscus petersi Ehrenberg. (Plate 1, figure 4.) Aulacodiscus petersi EHRENBERG, 1845- Monatsber. Akad. Wiss. Berlin, p. 361. SCHMIDT, 1874. Atlas Diat., pi. 35, fig. 4 (issued 1876), "Algoa Bai"; pi. 102, fig. 6, (issued 1886), "Simoda, Japan." Hustedt, 1929- Krypt. Flora, Deutschland, etc., Kieselalgen, Lief. 3, p. 505, fig. 282. Diatom circular with four prominent, spatula shaped spines near the margin; a clear line extends inward from each spine to the small clear central area; radial rows of small, closely spaced beads cover the areas between the radial clear lines. Immediately inward from the base of each spine the surface is raised into a pear-shaped area with about ten beads which are larger than those on the remainder of the diatom; these pyriform areas taper toward the center. Diameter, .0800 mm. Hypotype no. 3513 (Calif. Acad. Sci., Geol. Dept. Type Coll.), Joe's River, Barbados, West Indies. Eocene. The auxiliary spines on the pyriform elevations are very conspicuous but are slightly out of focus in figure 4- This diatom is so close to the drawings cited that we hesitate to identi- fy it otherwise. The original locality for A. petersi has been given as Africa. CALIFORNIA ACADEMY OF SCIENCES (Occ. Papers PLATE 1 Figures 1, 2- Actinoptychus hillabyanus Brun. Hypotype no. 3508 (Calif. Acad. Sci., Dept. Geol. Type Coll.). Joe's River, Barbados, West Indies. Eocene. Diameter, .116 mm. Figure 3. Aulacodiscus angulatus Greville. Hypotype no. 3511 (Calif. Acad. Sci., Dept. Geol. Type Coll.). Joe's River, Barbados, West Indies. Eocene. Diameter, .117 mm. Figure 4. Aulacodiscus petersi Ehrenberg. Hypotype no. 3513 (Calif. Acad. Sci., Dept. Geol. Type Coll.). Joe's River, Barbados. West Indies. Eocene. Diameter, .0800 mm. Figure 5. Aulacodiscus currus Hanna and Brigger, new species. Holotype no. 3518 (Calif. Acad. Sci., Dept. Geol. Type Coll.). Conset, Barbados, West Indies. Eo- cene. Diameter, .0914 mm. Figure 6. Aulacodiscus behani Hanna and Brigger, new species. Holotype no. 3509 (Calif. Acad. Sci., Dept. Geol. Type Coll.). Joe's River, Barbados, West Indies. Eocene. Diameter, .0756 mm. OCC. PAPERS CALIF. ACAD. SCI., NO. 45 (HANNA & BRIGGER) PLATE 1 vW ^- 8 CALIFORNIA ACADEMY OF SCIENCES (Occ. Papers Biddulphia punctata Greville. (Plate 2, figure 6.) Biddulphia punctata GREVILLE, 1864. Trans. Micr. Soc. London, n. s., vol. 12, p. 83, pi. 11, fig. 10. "Cambridge Estate, Barbados.*' Valve ovate with narrowly rounded ends, near each of which there is a high spine; the apex of the spine is a knob. Surface with a blank, steeply curved, transverse band with the convexity toward the center; markings con- sist of fine, sparse irregularly arranged beads with only a slight tendency to- ward arrangement in radial rows. Length, .0834mm.; width, .0540 mm.; height of spines, .0085 mm. Hypotype no. 3515 (Calif. Acad. Sci., Geol. Dept. Type Coll.), from Joe's River, Barbados, West Indies. Eocene. Our specimen does not differ significantly from the drawing which Gre- ville published. The species should be compared with Biddulphia costata Boyer (1922) from Chimborazo, Barbados. However, in place of terminal spines, that species has large, finely punctate processes. Brun (Le Diatomiste, 1895, vol. 2, pi. 22, fig. 14) illustrated a variety of fi. paracfa^a under the name "crefacea." The locality from which the diatom came does not seem to have been recorded, but it was probably Barbados. Brightwellia pulchra Grunow. (Plate 2, figure 2.) Craspedodiscus coronatus BRIGHTWELL, I860. Quart. Journ. Micr. Soc, vol. 8, p. 95, pi. 5, fig. 6. Brightwellia coronata (Brightwell), Ralfs in Pritchard, 1861. Infusoria, p. 940. Brightwellia pulchra GRUNOW in VAN HEURCK, 1883. Syn. Diat. Belgique, pi. 128, fig. 9. Brightwell's original specimen was a fragment, scarcely recognizable beyond the genus. It came from Barbados. Ralfs noticed the distinctness of the genus and described it as Brightwellia in 1861. Heterodictyon Greville, (Trans. Micr. Soc. London, n.s., vol. 3, 1863, p. 66) was described for two species, H. rylandsianum and H. splendidum, both from Barbados. The first with the large cellules at the margin is now selected for the genotype so that the second may be transferred to Brightwellia as B. splendida as Rattray and others have done. Hypotype no. 3514 (Calif. Acad. Sci., Geol. Dept. Type Coll.), from Joe's River, Barbados, West Indies. Eocene. Diameter, .0878 mm. No. 45) HANNA & BRIGGER: FOSSIL DIATOMS FROM BARBADOS 9 Coscinodiscus intersectus Brun. (Plate 2, figure 7.) Valve circular, nearly flat, with 17 small spines close to the narrow margin; a much heavier spine (?) is located in the exact center of the disk. Surface markings consist of radial rows of beads very distinctly separated from each other. Diameter, .0816 mm. Hypotype no. 3516 (Calif. Acad. Sci., Geol. Dept. Type Coll.), from Joe's River, Barbados, West Indies. Eocene. Coscinodiscus normanianus Greville. (Plate 2, figures 3, 4.) Valve circular, nearly flat but with a broad raised zone about halfway between margin and center; a small blank area in the center, remainder of sur- face marked with closely spaced beads, uniform in size. These are arranged in 19 radial sectors with all of the beads in radial rows which produce a very striking pattern. The pseudonodule is inconspicuous, if, in fact, the slight marginal dot is a true structure of this nature. Diameter, .1470 mm. Hypotype no. 3517 (Calif. Acad. Sci., Geol. Dept. Type Coll.), from Joe's River, Barbados, West Indies. Eocene. This is probably the species illustrated by Laporte and Lefebure(1929, pi. 11, fig. 73) as Cocinodiscus normanianus Greville from Barbados. Their photograph seems to be slightly out of focus and the beads are not as closely spaced in the center zone as in the presently considered specimen. However, individual variation in Coscinodiscus is so great that this distinction need not be sufficient for specific separation. The junctions of the sectors are somewhat reminiscent oi Coscinodiscus rothi but in that diatom they are distinct to the center. Hustedt (1928, p. 401) has published a drawing to show the characters of the junction in that diatom. Fenestrella picta Hanna and Brigger, new species. (Plate 4, figure 3.) Valve circular with 15 marginal scallops as in Anthodiscus; there are two spines on the disk, each a fourth of the diameter from the margin and each surrounded by a circular zone of radial beading set apart from that of the remainder of the disk. Where the two ordinary large processes would be on a Biddulphia, the border is thickened making these opposed "scallops" appear heavier that the other 13. Diameter, .0732 mm. 10 CALIFORNIA ACADEMY OF SCIENCES (Occ. Papers PLATE 2 Figure 1. Aulacodiscus hirtus Barker and Meakin. Hypotype no. 3534 (Calif. Acad. Sci., Dept. Geol. Type Coll.). Joe's River, Barbados, West Indies. Eocene. Diameter, .103 mm. Figure 2. Brightwellia pulchra Grunow. Hypotype no. 3514 (Calif. Acad. Sci., Dept. Geol. Type Coll.). Joe's River, Barbados, West Indies. Eocene. Diameter, .0878 mm. Figures 3, 4. Coscinodiscus norm ani anus Greville. Hypotype no. 3517 (Calif. Acad. Sci., Dept. Geol. Type Coll.). Joe's River, Barbados, West Indies. Eocene. Diameter, .1470 mm. Figure 5. Entogonia complexa Hanna and Brigger, new species. Holotype no. 3518 (Calif. Acad. Sci., Dept. Geol. Type Coll.). Joe's River, Barbados, West Indies. Eocene. Length, .0670 mm. Figure 6. Biddulphia punctata Greville. Hypotype no. 3515 (Calif. Acad. Sci., Dept. Geol. Type Coll.). Joe's River, Barbados, West Indies. Eocene. Length, .0834 mm. Figure 7. Coscinodiscus intersectus Brun. Hypotype 3516 (Calif. Acad. Sci., Dept. Geol. Type Coll.). Joe's River, Barbados, West Indies. Eocene. Diameter, .0816 mm. OCC. PAPERS CALIF. ACAD. SCI., NO. 45 (HANNA & BRIGGER) PLATE 2 V •,^^- y vm. 6 12 CALIFORNIA ACADEMY OF SCIENCES. (Occ. Papers HOLOTYPE no. 3524 (Calif. Acad. Sci., Geol. Dept. Type Coll.), from Joe's River, Barbados, West Indies. Eocene. Greville (Trans. Micr. Soc. London, n.s., 1863, vol. 3, p. 68, pi. 4, fig. 3.) described this genus forthe species Fenestrellaharhadensis. In 1891 Brun (Esp. nouv. Mem. Soc. Phys. d'Hist. Nat. Geneve, vol.31, pt. 2, no. 1, p. 27, pi. 19, figs. 7, 8) described two more species from Oamaru (fig. 7) and Yedo, Japan (fig. 8). All three of these are very beautiful diatoms but differ radi- cally from the one here described. The one from Joe's River is the only one with a scalloped margin. Entogonia complexa Hanna and Brigger, new species. (Plate 2, figure 5.) In valve view this diatom is a long oval with heavily dotted areas at each end; across the center there is a band with large, flat, more or less cir- cular plate-like protuberances; a centrallongitudinal thickening of silica cross- es this band and terminates in two half round openings; the remainder of the area is covered with the same plate-like markings of the central band. Length, .0670 mm.; width, .0270 mm. HoLOTYPE no. 3518 (Calif. Acad. Sci., Geol. Dept. Type Coll.), from Joe's River, Barbados, West Indies. Eocene. This rather remarkable diatom has not been found in any of the litera- ture we have consulted. It is obviously a biangulate form of Entogonia, the only other similar one in Barbados material being Triceratium biangulatum Greville which Bergon (Le Diatomiste, 1892, vol. 1, p. 136, pi. 3, figs. 7, 8), considered to be merely a biangulate variation oi Entogonia davyana(Gteville). The name "Heilhergia barbadensis" Greville (Trans. Micr. Soc. London, vol. 13, 1865, p. 100, pi. 8, figs. 8, 9) was based on a biangulate form of Entogonia which Truan and Witt (Diatoms from Jeremie in Hayti, 1888, p. 16, pi. 4, figs. 2, 3) made a variety of Entogonia davyana Greville. Entogonia versuta Hanna and Brigger, new species. (Plate 3, figures 1, 2, 3, 4, 5.) Valve triangular with convex sides; a coarse rounded knob at each cor- ner; along each side there are six smaller, squarish knobs and from each a thin radial bar extends to a central triangle. In the central triangle there is a beau- tiful rosette of elongate petals; over the surface, outside of the central trian- gle small dots are widely scattered. Diameter, base to apex, .0650 mm. HOLOTYPE no. 3519 (Calif. Acad. Sci., Geol. Dept. Type Coll.), from Joe's River, Barbados, West Indies. Eocene. While the border markings set this diatom apart from others we have found in the literature it shows some similarity to Entogonia formosa Bergon. No. 45) HANNA & BRIGGER: FOSSIL DIATOMS FROM BARBADOS 13 This was first recorded from Jeremie, Hayti (1888) but was then considered to be Greville's Entogonia puncticulata. The central portion is almost exactly the same as Bergon showed in his monograph of the genus (1882, p. 146, pi. 14, fig. 13). It has also been figured by Schmidt (1896, pi. 203, figs. 2, 4). Per- haps the best illustration to date is that of Laporte and Lefebure (1929, pi. 1, fig. 5. Separate names have been given to numerous variations of Entogonia from Barbados and Hayti and we hesitate to add still another. This would not be done if connections between it and the other two species mentioned could be found. Glyphodiscus dubiosus Hanna and Brigger, new species. (Plate 3, figures 8, 9.) Diatom circular, nearly flat with three short nodes or spines equally spaced about a third of the distance from the margin to the center; midway be- tween these there are three faint depressions; inner side of border with short but distinct bars of uneven length; remainder of surface sparsely marked with radial rows of short transverse bars; all of the bars can be resolved into beads with sufficient numerical aperture and magnification. The surface is then seen to be divided into six sectors of very slight difference in elevation. Diameter, .0296 mm. HoLOTYPE no. 3520 (Calif. Acad. Sci., Geol. Dept. Type Coll.), from Joe's River, Barbados, West Indies. Eocene. This interesting diatom is believed to be a member of the Glyphodiscus group although the most common species have the ocelli close to the margin. However, Schmidt (1882, pi. 80, fig. 10) illustrated one from Barbados which has the ocelli very much as in the present form. His figure shows the markings as radiating lines and not as beaded zones as in the present form and this led him to consider the possibility of his figures 9 and 10 being varieties of Liostaphania rotula Ehrenberg. Liostephania (?) japonica Brun (1889, p. 38, pi. 4, fig. 2), a fossil from Japan, does have beaded sculpture but not in zones as in the present form; and where ocelli would be expected, there are four double spine-like processes. According to Payne (1922), all of the examples of Liostephania, as well as of several other named genera, are external and internal molds or casts of diatoms. The present form does not appear to fall in that category. Some biologists have regretted the fact that there are odd shaped spore cases produced by some groups of diatoms and that these can rarely be asso- ciated with the species which has produced them. It has been suggested that such objects should not be included in systematic taxonomy but there is not uniform agreement in this respect. The reason for giving them names in a classification is that they have very definite use in determination of ages of sediments and are often as useful for that purpose as any other fossils. 14 CALIFORNIA ACADEMY OF SCIENCES (Occ. Papers PLATE 3 Figures 1-5. Entogonia versuta Hanna and Brigger, new species. Holotype no. 3519 (Calif. Acad. Sci., Dept. Geol. Type Coll.). Joe's River, Barbados, West Indies. Eocene. Diameter, base to apex, .0650 mm. Figures 6-7. Helminthopsis sokoli Hanna and Brigger, new species. Holotype 3521 (Calif. Acad. Sci., Dept. Geol. Type Coll.). Joe's River, Barbados, West Indies. Eocene. Length, (fig. 6.) .2314 mm. Figures 8-9. Glyphodiscus dubiosus Hanna and Brigger, new species. Holotype no. 3520 (Calif. Acad. Sci., Dept. Geol. Type Coll.), Joe's River, Barbados, West Indies. Eocene. Diameter . 0296 mm. OCC. PAPERS CALIF. ACAD. SCI., NO. 45 (HANNA & BRIGGER) PLATE 3 i 1 !(( c ( ( ( D-'^ 1^ ,VVF^' <* 3 V 1 .*,-.* ^