370 Systematic Paleontology 



lateral edges are acutely carinate but not crenulated. The palmar face is 

 much less convex than the back and both are rather abruptly contracted 

 close to the wrist. The pollex is subtriangular in section. The surface is 

 nearly smooth, without punctures. 



The specimen from Post 105: Length of hand with pollex 11.7 mm.: 

 length of palm 9 mm. ; breadth about 5 mm. ; thickness 2.5 mm. 



Specimen from li miles east of the Maryland-Delaware Line : Length 

 with pollex 14 mm. ; length of palm 9.8 mm. ; breadth 7 mm. 



Callianassa clarki was found at Post 105 and C. mortoni also occurs 

 elsewhere in the Canal. The hands described above may prove to belong 

 to one of these species. It is a peculiar circumstance that no similar 

 remains have been found in the New Jersey deposits, which have supplied 

 large numbers of the large claws of Callianassa. 



Occurrence. — Matawan Formation. One and one-half miles east of 

 the Maryland-Delaware Line on the south side Chesapeake and Delaware 

 Canal; Post 105, Chesapeake and Delaware Canal, Delaware. 



Collection. — Maryland Geological Survey. 



