68 J: PROCEEDIXGS OF THE NATIONAL MUSEUM. vol.xxhi. 



OBOLUS (?) MENEGHINI, new species. 



Lingula j)etalon Borxemanx, Nova Acta der Kais. Leop. -Carol. Deutsch. Acad. 



Naturf., LVI, p. 438, pi. xix, figs. 12-14. 1891. 

 OholeUa (?) sp. Bornemaxx, Nova Acta der Kais. Leo]). -Carol. Deutsch. Acad. 



Naturf., LYI, p. 440, pi. xix, fig. 18. 



Rounded triangular frontal margin at times almost straight. Shells 

 rather flat, their arching ])eing greatest in the middle. Concentric 

 and rather coarse lines of growth. Size, 5-11 mm. 



Occurrence: In yellow, friable sandstone of Punta Pintau (Canal- 

 grande) and of Gruguetta. Sardinia. 



The specimen referred to Obolella ( i ) sp. is from the slate of Porto 

 Canalgrande. It is not an Obolella, and may be identical with the 

 species from the sandstones. 



The shells referred to Ltngida pdalon suggest Obolus in form and 

 surface ornamentation and are tentatively referred to that genus. 



OBOLUS TETONENSIS, new species. 



The general form, convexity, and appearance of this species is so 

 much like that of Oholus inathia/is that a full description is unnec- 

 essary. It varies from that species in the shorter, more transverse 

 dorsal valve, and the narrower outline of the ventral valve toward the 

 beak. 



This species occurs in great abundance in the thin bedded limestone 

 in the upper portion of the Cambrian section of the Teton Range, 

 Wyoming, in association , with BWhigsella ])eplna and Oholus {Lhigu- 

 lepis) acuminatus var. meeM. AVhat appears to be the same species 

 occurs nearly TOO feet lower in the section in a thin bedded sandstone. 

 The dorsal valve is broader and more transverse posteriorly than the 

 dorsal valve from the upper horizon. 



Formation and locality. — Middle Cambrian, on the divide at the 

 head of Sheep Creek, near north end of the Teton Range, AVyoming. 

 Thin bedded limestones, Belt Park, 6 miles out from Neihart. ^Montana. 

 Three miles southeast of Malad City, Idaho. A smaller form col- 

 lected by Dr. A. C. Peale in Bostwick Canyon, Bridger Range, Mon- 

 tana, may belong to this species. It occurs in a line-grained sandstone 

 low down in the Paleozoic section. 



OBOLUS (?) ZOPPI, new species. 



Oboldla crassa Borxemanx, Nova Acta der Kais. Leop. -Carol. Deutsch. Acad. 

 Naturf., 1891, LVI, p. 439, pi. xix, figs. 15-17. 



Broadly oval or circular,- Avith somewhat pointed vertex. Shells 

 stronglv arched, one somewhat more than the other. Thev are 

 marked with prominent concentric lines; no radial striation is noticed. 

 Found in a red-yellow sandstone layer not far from the houses of 

 ■Canalgrande, Sardinia, on the road to Punta Pintau. 



