No. 403.] MWORTH-AMERICAN INVERTEBRATES. 589 
E. Propodus of third ambulatory leg as broad as long, 
or nearly so . . P. chetopterana Stimpson, M 
£’. Propodus of third ambulatory leg distinctly longer 
than broad. 
F. Dactylus of third ambulatory leg more than 
half the length of the propodus, measured on 
the posterior margin. 
G. Second pair of ambulatory legs slender, 
filiform, subcylindrical 
. sayana Stimpson, M 
G'. Second pair of ambulatory legs compressed, 
not extremely slender nor filiform. 
H. Cardiac ridge sinuous, in dorsal view 
P. occidentalis Rathbun, AP 
H’. Cardiac ridge straight, or nearly so, in 
dorsal view 
P. californiensis Rathbun, D 
F”. Dactylus of third ambulatory leg less than half 
the length of the propodus, measured on the 
posterior margin . P. littoralis Holmes, P 
LX. Transverse crest on the cardiac region extending across 
the entire carapace P. cristata Rathbun, sp. nov., M 
Fic. 11. FiG. 12. Fic. 13. 
Fic. 11. — Pinnixa longipes. 
Fic. 12.— pb rese pen outer maxilliped. 
Fic. 13. m, 9. 
C. Pollex as long, or nearly as long, as the dactylus, and not bent 
downward. 
D. Merus of third ambulatory p pus than half the width 
of the carapace . . longipes (Lockington), P 
D’. Merus of third ambulatory i shorter than half the width 
of the carapac 
E. Length of Caria half its width 
P. cylindrica (Say), SG 
E'. Length of carapace much less than half its width 
P. tubicola Holmes, D 
B'. Pollex "m — only by the spiniform angle of the 
palm . . P. monodactyla (Say), American? 
! Type, one female, Beaufort, N. C. (Union College collection). 
