DECAPODS 181 
The characters most useful in determining the species are given below: 
The carapace is roughened antero-laterally, but not conspicuously so. 
The frontal lobes are slightly sinuous and oblique, the outer tooth 
faintly indicated. 
The anterior margin of the third antero-lateral tooth (or tooth N of 
Dana) is in line with the truncate margin of the second tooth or the one 
coalesced with the outer orbital tooth. 
The carpus of the chelipeds is slightly roughened. 
The hand is smooth, without a tooth on the upper margin; the proxi- 
mal end of the inner margin of the upper surface is, however, well 
marked. 
The dark color of the fingers does not run back on the palm. 
The carpal joints of all the ambulatory legs are slightly bilobed on the 
anterior or upper margin. 
The propodal joints have a convex anterior margin without lobes. 
Dimensions.— Male, length 22.5 mm., width 33.8 mm., proportion of 
length to width 1:1.5, fronto-orbital width 16 mm., proportion of fronto- 
orbital width to width of carapace 1: 2.11. 
LOPHOPANOPEUS FRONTALIS Rathbun. 
Plate vu, fig. 8. 
Distribution.—San Diego, California. The locality ‘Monterey’ cited 
for this species is an error. 
The carapace is almost smooth. 
The frontal lobes are markedly oblique and sinuous, the middle lobes 
very convex. 
The third antero-lateral tooth is more produced than the second tooth. 
The carpus of the chelipeds is smoother than in Z. dellus. 
The hand is smooth, with a large tooth projecting inward on the inner 
side of the upper margin and extending half the length of the upper 
margin. 
The dark color of the fingers runs back on the palm; in this respect 
differing from all other allied species. 
The carpal joints of all the ambulatory legs are slightly bilobed on 
the anterior or upper margin, 
The propodal joints have a convex anterior margin, but are narrower 
than in Z. del/us. 
Dimensions.—Male, length 17.2 mm., width 23.7 mm., proportion of 
length to width 1 : 1.32, fronto-orbital width 12.5 mm., proportion of fronto- 
orbital width to width of carapace 1: 1.9. 
