92 NEW YORK STATE MtJSEUM 



minganensis the glabellar furrows likewise do not extend 

 back to the neck-ring. Raymond does not recognize the genus 

 Metopias which originally was created by Eichwald, subsequently 

 abandoned by the same author, but revived by Schmidt (op. cit., 

 p. 30) for just such species with strongly forward bulging glabella 

 and glabellar furrows that fail to Teach the occipital groove. Reed 

 has shown that in Amphilichas the side lobes are the fused second, 

 third and fourth glabellar furrows and that the glabellar furrows 

 are the first pair prolonged by the uniting of the inner ends of all 

 three pairs of furrows. It is for this reason obvious that Metopias 

 represents an earlier stage of development of Amphilichas, as also 

 suggested by Raymond's observation in the young of A . 

 minganensis. If the Metopias character of the glabellar 

 furrow, then, proves to represent a genetic stage of development 

 of Amphilichas, also represented in the ontogeny of Amphilichas, 

 it is worthy of recognition as determining a generic group. 



Horizon and locality. Both the glabella and pygidium came 

 from the Rust collection and were collected in the Trenton lime- 

 stone at Trenton Falls. 



Ceratiocaris (Limnocaris) salina nov. 



Plate 33, figures 1-^5 



Description. Carapace-valves small, pod-shaped, about three 

 times as long as wide, widest at the anterior third whence each 

 valve contracts rapidly to the acutely pointed or mucronate antero- 

 dorsal margin and gradually to the posterior margin which is 

 subrectangularly truncated with rounded corners. The dorsal 

 margin is nearly straight to the anterior extremity which is 

 slightly contracted. The ventral and anterior margins are fur- 

 nished with a filiform raised border, the dorsal margin apparently 

 with a flat, vertical hinge-border and the posterior margin with a 

 frill-like thin extension. The eye tubercle is very large and 

 prominent and situated well forward. No surface markings have 

 been observed on the specimens, which are mostly internal casts. 

 The rostrum is also relatively large and apple-seed shaped in out- 

 line. The abdomen is notably small and protruding in the speci- 

 mens only with the telson. Not more than five segments have been 

 observed, the ultimate being a little larger than the others. The 

 telson is short and blunt and the two shorter cercopods closely 

 adhere to it in all the specimens. 



