1886] dol [Packard. 



with a transversely striated surface. This is^fbllowed by another similar 

 appendage, proceeding in the same manner from the penultimate seg- 

 ment. The dorsal edge of the specimen shows that one of the correspond- 

 ing 'foot-gills ' of the opposite side has been bent back upon itself, and 

 thus thrust out of place. The free ends of these paddle shaped appendages 

 are attenuated to more or less rounded points. They do not show any evi- 

 dence of a marginal fringe. These gill feet are no doubt analogous to the 

 same supplementary abdominal organs in Nebalia." 



I do not understand from the foregoing description, the nature of the 

 so-called appendages, especially since they are not figured, but will now 

 proceed to call attention to those noticed in a specimen sent me a year ago 

 by J. C. Carr, Esq., of Morris, Illinois, which occurred in a nodule from 

 the Carboniferous beds of Mazon creek at Morris. 



As soon as I examined the fossil, the indications of broad lamellate 

 appendages of several pairs were at once apparent. Owing to the incom- 

 plete state of preservation of the dorsal and ventral edges of the valves I 

 was at a loss to what group to refer the fossil. It was apparently a Phyl- 

 locariclan, but seemed to differ from most of the genera described. I 

 therefore considered it as the type of a new genus intermediate between 

 Ceratiocaris and Aristozoe, and named it Cryptozoe; it may be called Cryp- 

 tozoe problematicus. After, however, comparing the specimen with Dr. 

 "Woodward's figure of the Carboniferous Ceratiocaris oretoneiisisWoodv?. 

 and G. truncatus Woodw. [Geological Magazine, viii, March. 1871), and his 

 figure of G. papilio Salter and G. stygia Salter {Geological Magazine, Sep- 

 tember, 1885), I was inclined to provisionally regard it as belonging to 

 that genus. 



But on consulting my friend, Mr. C. E. Beecher, who has worked so 

 faithfully on the fossil Phyllocarida, he kindly sent me the following 

 opinion : 



Albany, Dec. 30, 1885. 



The typical Ceratiocaris (see McCoy's description) differs from your 

 specimen in its semi-elliptical outline, with the abruptly truncated poste- 

 rior end and evenly convex valves. 



Your species has a short hinge-line, very broadly rounded posterior end, 

 and the cephalic and thoracic regions of the carapace are well defined. 

 These are characters which do not belong to Ceratiocaris when strictly 

 defined. The contour of the dorso-anterior extremity would seem to indi- 

 cate the presence of a well-developed rostrum. The typical Ceratiocaris 

 are from the Silurian system, and I very much doubt their extension into 

 the Carboniferous, although they have been noted in the Devonian. I 

 have not seen the article by Woodward and Jones which you mention. 



I should be inclined to consider this as a type of a new genus. 



It is very interesting, especially as furnishing some information as to 

 the appendages. 



Chas. E. Beecher. 



