No. 398.) WORTH-AMERICAN INVERTEBRATES. 133 
THE SPECIES OF CANCRIDA. 
Genus Cancer Linnæus. 
Key to Species. 
A. Ambulatory legs very broad and flat, especially those of the last pair 
C. magister Dana APD 
A’, Ambulatory legs of moderate width. 
B. Fronto-orbital width small, about one-fifth width of carapace. 
Front strongly advanced beyond outer orbital angles 
C. productus Randall APD 
B'. Fronto-orbital width more than one-fifth width of carapace. Front 
not greatly advanced beyond outer orbital angles. 
Fic. 1. — Cancer magister. 
C. Color on the fingers extending from the li not more than 
half the length of the fingers. 
D. Carpus of cheliped with two spines at inner angle, one 
below the other. 
E. Antero-lateral teeth shallow, projecting little from 
the carapace. Carapace very slightly areolated 
| C. gracilis Dana APD 
E’. Antero-lateral teeth strong, projecting well out from 
. the carapace. 
F. Fronto-orbital width one-third the width of the 
carapace. Carapace strongly areolated 
C. gibbosulus (de Haan) APD 
F’. Fronto-orbital width nearly half the width of 
the carapace. Carapace slightly areolated 
C. jordani Rathbun, sp. nov.,! D 
: 2e U.: S ies Mus. No. 22868, Monterey Bay, Harold Heath, collector. 
The ne species noticed in this paper will be described in full in the Proceedings 
of the Parr pn National Museum. 
