Beede: New Species of Fossils 



11 



terminates with a sharper angle. It is less sharply separated from the shell 

 and has a broader marginal sinus below it. The anterior ear of the right 

 valve is separated from the shell by a deep marginal sinus extending more 

 than half way to the beak. 



The body of the right valve is ovate in outline, most convex above the 

 middle, with the beak projecting slightly above the hinge. The anterior 

 part of the larger specimens possesses a wide zone of stronger growth marks 

 and fainter radiating sculpturing than is found on the rest of the valve. 

 The surface of the valve is covered with three ranks of radiating costae. 

 The largest, eight to twelve in number, appearing at rather wide intervals, 

 reach the beak. Between the larger costae there are Prom two to six smaller 

 costae. All these ribs are split, each one being doubly carinated at its crest, 

 or it is formed of two similar ones, giving the shell a unique appearance. 

 These costae extend over the ears, being much stronger on the anterior one, 

 on which seven or eight can be counted while four or five faint ones appear 

 on the posterior ear. Both coarse and fine growth lines ornament the valve. 

 The former are rather conspicuous and are rather widely spaced. The larger 

 costae are very indistinctly developed on the posterior half of the shell 

 and are quite prominent on the anterior half. There seems to be some 

 evidence that the surface was roughened by vaulted lamellae, but not marked- 

 ly so. 



A faint impression of the right valve shows it to be very flat, and to be 

 .marked by nearly even radiating costae of moderate size. Other characters 

 are not well shown. Length of shell about 60 mm.; height 51 mm.; convexity 

 of left valve 7 mm. Smaller specimen, hinge is 31 mm.; height of same 

 specimen 40 mm.; length of shell 39 mm. 



This species is similar in outline and superficial appearance to D. texanus, 

 Girty from the rocks below, but its unique split-rib ornamentation and 

 probably thinner shell separate it at once from that shell. 



Quarries in the west part of Ballinger, Texas, on the north side of the 

 Colorado river. 



FUSULINA 



The nomenclature of the American Fusulinas as applied by von Staff 

 has been discussed by Girty ^ so far as the application of terms is concerned. 

 It only remains to confirm some of Girty's suspicions in the matter with 

 facts, and to make a few additions. 



Meek described Fusulina cylindrica var. ventricosa, from the Juniata 

 bridge and Manhattan. This species was figured in Meek's Paleontology 

 of the Upper Missouri- and the specimen is clearly a Fusulina, and not a 

 Girtyina. Furthermore the specimens described by von Staff from Illinois 

 are clearly Girtyinas and not Fusulinas. In the third place, Girtyina can 

 not be legitimately considered a subgenus of Fusulina. It is a distinct 

 genus, as I shall point out in another place. This leaves Fusulina ventricosa 

 a distinct species, from the basal Elmdale formation, of Kansas. 



Girtyina is confined to the rocks below the Bethany Falls hmestone, 

 or, to the Des Moines stage of the Pennsylvanian. So far as I am at present 



lOn the Names of American Fusulina, Jour. Geol. XXII (1914), 237-242. Dis- 

 cussion of Monograph of American Fusulinas by Hans v. Staff, Paleontographica, 

 Band 59, 4te Lieferung (1912), 157 IT. 



"^Pal. Upper Missouri (1884), pp. 14-15, pi. i, figs, 6a-g. 



