158 NEW YORK STATE MUSEUM 



Measurements of three specimens are : 1) anteroposterior 5 mm, 

 lateral 7.8 mm; 2) anteroposterior 5 mm, lateral 6 mm; 

 3) anteroposterior 4 mm, lateral 5.2 mm, depth 1 mm. 



craniella Oehlert 

 Craniella hamiltoniae (Hall) 



Pal. N. Y. 4:27, pi. 3 



This species is fairly common in beds VII and VIII. All the 

 shells found are attached to Orthoceraisi, and are of the normal 

 adult proportions. 



STROPHEODONTA Hall 



Slropheodonta (Leptostrophia) perplana Conrad 



Pal. N. Y. 4:98, pi. 11, 12, 17, 19 



Fragments of several individuals have been found in bed VII, 

 and one nearly complete pedicle valve in bed VIII has a length 

 of 19 mm and width of 25 mm. 



Stropheodonta inequistriata (Conrad) 



Pal. N. Y. 4:93, pi. 12 



Pedicle valves of this species are fairly common in bed VII. 

 The largest specimen found has a length of 14.5 mm and width of 

 21 mm. The surface markings are more delicate than those of 

 the average specimen from the Hamilton shales, but are other- 

 wise similar. 



orthothetes Fischer de Waldheim 



Orthothetes chemungensis arctostriata Hall 



Pal. N. Y. 4:71, pi. 9 



The specimens are much broken, but all show the character- 

 istic sharply elevated costae and fine concentric striae. One 

 fairly perfect mold of a pedicle valve is of the normal form and 



size. 



chonetes Fischer de Waldheim 



Chonetes mucronatus Hall 



Pal. N. Y. 4:124, pi. 20, 21 



This species is common in all of the lower shales except the 

 upper fissile part of bed D and bed E, where it has not been 



