TRENTON CONGLOMERATE OF RYSEDORPH HILL 67 



tion of the eastern North American forms from European forms, 

 a suggestion which is corroborated by the close relationship of 

 the New York and Newfoundland forms with the common tuber- 

 culate C y b e 1 e verruc o s a Dalm. of the Caradoc and Llan- 

 deilo of Great Britain. The specimen in the writer's hands dif- 

 fers in no essential features from the pygidia figured by McCoy 1 

 as Z e t h u s atractopyge, s e x c o s t a t u s and r u g o - 

 8us, which names are synonyms of C y b e 1 e v e r r u c o s a. 



Horizon and locality. Gray limestone pebble of Kysedorph hill. 



(Group 7) 



calymmene Brongniart 



Calymmene senaria Conrad. N. Y. geoL sur. 4th an. rep't Pal. 



1841. p. 49 



A large head, marked by its long shovel-shaped anterior 

 expansion as belonging rather to this species than to C. c a 1 1 i- 

 c e p h a 1 a Green 2 was found in the black limestone. This is the 

 common Trenton form, while C. c a 1 1 i c e p h a 1 a occurs in the 

 Trenton as well as in the Lorraine beds. (Group 5) 



jCeraurus Green 



Ceraurus pleurexanthemus Green. Monograph tril. N. Am. 1832. 



p. 83 



Cranidia and free cheeks are common in the pebbles of gray 

 crystalline limestone and rare in those of compact black lime- 

 stone. This form has a very considerable vertical range and 

 wide geographic distribution; it ranges from the Lowville lime- 

 stone to the Lorraine beds and has been found in Baffin Land 

 (Schuchert) as well as in Manitoba (Whiteaves) and in the east- 

 ern and central parts of the United States. (Groups 5, 7) 



sphaerocoryphe Angelin 

 Sphaerocoryphe major sp. nov. 



Cf . Sphaerocoryphe r o b u s t u s Walcott. Cm. quar. 

 jour. sci. 1875. 2:273 



PL 4, fig. 13, 14 



Two cranidia with spheric glabellar frontal lobes were found in 

 the black limestone pebbles which are filled with specimens of 



1 Sedgwick and McCoy, Brit. Pal. foss. 1855. pi. 1G, fig. 1-8. 



2 On the relation of these species see GeoL Minn. Pal. 1897 v, 3, pt 2, p.699, 



