NOTEiS OX PALEOZOIC CRUSTACEANS 101 



In the uncertainty which prevailed at the time of preparing 

 vol. 7, Paleontology of Neiv York, with regard to the generic char- 

 acters of iseveral of the species above mentioned, they were re- 

 ferred to various genera, but we are now aware that all the fol- 

 lowing have the structure of R h i n o c a r i s and are referable 

 to that genus. 



Rhino caris columbina Clarke (pi. 4, fig. 14). Ham- 

 ilton shales, TichenoT's gully, Canandaigua lake and Livonia 

 salt shaft, 350 feet. 



Ithaca beds. Laurens and in the vicinity of Noblesville, 

 Otsego CO. 



R. columbina var. li von en sis (pi. 4, fig. 15, 16). 

 Hamilton shales. Livonia salt shaft, 350 feet. 



R. scaphoptera Clarke (pi. 4, fig. 10, 11). Hamilton 

 shales. Tichemor's gully, Canandaigua lake; Livonia salt 

 shaft, 350 feet. 



Ithaca heds. Canasawacta creek, Norwich; near Phelps 

 crossing, Chenango co. 



R. (T r p i d a r i e) h a m i 1 1 o n i a e Hall and Clarke. 

 Hamilton shales. Tichenor's gully, Canandaigua lake. 



R. (El 1 y m c a r i s) c a p s e 1 1 a Hall and Clarke (pi. 4^ fig. 

 12, 13). Hamilton shales. Canandaigua lake. The original 

 of this species was a small and obscure carapace. Other 

 specimens of larger form and characterized likewise by the 

 absence of a spine on the posterior margin occur in the Ithaca 

 beds near Pitcher and at Pharsalia Hook, and show the 

 R h i n o c a r i s hinge structure. 



R. (M e s o t h y r a (D i t h y r o c a r i s ?) ) veneris Hall 

 and Clarke. This species, very well 'disitinguished in the 

 character of its outline, is from the blue black passage beds 

 from the Marcellus into Hamilton shales, on Mud creek, town 

 of Canandaigua. 



The species described by the writer asRhin.(?) bipennis 

 (pi. 4, fig. 9) from the horizon of the Sherburne siandstone (lower 

 beds of the Ithaca formation) one fourth mile south of the ceme- 



