J 80 

 Genus CRANIELLA. Oehlert. 



I Ety.: Diminutive of crania.] 



1888: Bull, de la Soc. d'Etudes Scientif. d'Angers, p. 37. 1892: Pal. X. Y.. 

 Vol. VIII., Pt. I., pp. L58, 170.) 



Shell somewhal Irregular, with ;m outline varying from 

 nearly circular to almost quadrangular; no pedicle opening, 

 hut lower valve cemented, by its whole surface, to rocks 

 or other shells; upper valve more or less elevated, apex 

 behind the center; four large adductor muscle impressions, 

 one pair near the center; outside of these lie S-shaped vas- 

 cular impressions. 



Craniella iia.mii.tom.e. Hall. (Fig. 87.) (Pal. N. Y., 

 Vol. IV.. p. 27, PI. III.) 



Distinguishing Characters. — Large size; adaptation to 

 surface on which ifc is attached ; irregularly rounded outline: 

 and concentric lines of growth about an eccentric apex. 



Fra. 87. Craniella hamiltonice. Top and lateral views of a dorsal valve ; a group of 

 ventral valves attached to a valve of Cypricardella bellistriata; enlargement of the interior 

 ■ •i a ventral valve (from Hall i. 



Found in the coral layer of the Moscow shale, at Section 

 5 i?) and just above it; also in the Stictopora and Demissa 

 beds,a1 Section 5; in the shale below the A. spiriferoides bed 

 and two feet below the Trilobite beds, in Avery's Creek. 



Genus PHOLIDOPS. Hall. 



| Ety. : PhoKdoa, a scale] 



(1859: Pal. X. Y., Vol. III., p. 489. 1892: Pal. N. Y.. 

 Vol. VIII., I't. I., p. 15.-,.) 



Shells small, with equal valves, patella-like in outline; 

 they are inarticulate and unattached, without pedicle 



