li-ili 



Found in the Stictopora and Demissa beds, at Section 5 

 I rare) ; in the shale nine to seventeen feet below the Encrinal 

 limestone. a1 Section 7 (rare); and at "Hamburg, Erie 

 County, N. Y." (Hall.) 



A.VICULOPECTEN insignis. Hall. (Fig. 154.) (Pal. X. Y.. 

 Vol. V.. Pt. I., p. 34, Pis. I.. III.. LXXXI.) 



Distinguishing Characters. — Small size: moderate ob- 





Fig. 1-V1. Avicvlojwcten insignia. A left valve: interior of a right valve, from Ham- 

 burg. Erie ('<>.. N. Y.. the specimen "being embedded in shale shows the ornamentation 

 on the interior (from Hall). 



liquity; hinge nearly equal to the length of the shell: nearly 

 central beak : strong radiating costa?. 



Found at " Hamburg. Erie County, N. Y." (Hall. ) 



Genus LYRIOPECTEN. Hall. 



[Etv. : Lyrion, 13-re — Pecten.] 

 (1884: Pal. X. Y., Vol. V, Pt. L. p. xii.) 



Shell like Aviculopecten, but differing from that genus in 

 its short hinge line and very small anterior ear. 



Lyriopecten orbicularis. 

 Hall. (Fig. 155.) (Pal. X. Y.. 

 Vol. V., Pt. L, p. 42, Pis. IV.. 

 LXXXIL) 



Distinguishing Characters. — 

 Large size: orbicular outline; 

 convex left valve; concave, flat. 

 or slightly convex right valve: 

 numerous strong, rounded radii 

 crossed by concentric sharp lines. 

 and separated by broader con- 

 cave spaces. 



V* 



Fiq. l">. Lyriopecten orbiculatus. 

 The type specimen from the Encrinal 

 limestone, on the shore <>f hake Erie. 

 N. V (from Hall). 



