CRUSTACEA. 
107 
of feet scarcely one and one-fourth times the length 
of the carapax. 
Length of shell, in the present specimen, (ros- 
trum inclusive,) scarcely lfV inches, but, probably 
attains a greater size. 
A single specimen, brought by Mr. Nuttall from 
Upper California. 
Compared with such specimens as I have seen 
of the L. canaliculata, the shell here is less convex, 
the rostrum more flattened above, the anterior feet 
more smooth, and the spines and tubercles more 
numerous. 
It may be named, provisionally, L. affinis, allied 
to L. emarginata, Leach, and to L. dubia, Edwards, 
which last is described as being less spinous than 
the L. canaliculata. 
Genus Herbstia, (Edwards.) 
H. parvifrons. Mus. Acad. 
Corpore depresso, in latere spinoso, pedibus spinosis, 
leviter dilatatis, manibus lsevigatis, dactylis apice serru- 
latis. 
Body flattened above, punctured, somewhat hairy; 
sides spinous, especially anteriorly; rostrum very 
short; feet spinous above; hands of the anterior 
pair with only a few very small spines at their base ; 
pincers without teeth, except towards their apices, 
where, for at least one-third of their whole length, 
they are hollowed out on their prehensile side, and 
serrated laterally, so that, when closed, they become 
interlocked at their extremities by means of the 
serratures. 
