286 MARINE INVERTEBRATES 
one inch long, with prominent spines on the sides of the carapace, which 
narrows in front into a long beak ending in two spines. It is red and 
green above, red beneath. (Plate LXIII.) 
Genus Sternorhynchus 
S. sagittarius. Thisis one of the most delicately formed of the spider- 
erabs. The body has narrow longitudinal stripes of light and dark color. 
It lives offshore from Cape Hatteras southward. 
Genus Epialtus 
E. productus, the kelp-crab. This crab inhabits the coasts of Cali- 
fornia and Oregon, and is found among seaweeds on rocks just below 
low-water mark. The carapace is smooth, is quadrate in form, is about 
two inches long and broad, has two spines on each side, and hasa promi- 
nent denticulated rostrum. This is the most common spider-crab of the 
Pacific (California) coast. It is olive-green, thus simulating in color the 
kelp among which it lives. (See page 285.) 
Genus Pitho 
P. aculeata. The carapace has six spines on each side, the middle 
two being sometimes partly united; the general outline is pentagonal ; 
the length about one inch. Quite common on the Florida coast. 
(Plate LXIII.) 
Genus Lambrus 
LL. pourtalesii, 
the long-armed 
spider-crab. The 
carapace is broader 
than it is long and 
has three elevations 
all covered with 
spines. The general 
surface is pitted and 
granulated ; the ros- 
trum points down- 
ward; the chelipeds 
are very long, the 
margins armed with 
se spines; the breadth 
Lambrus pourtalesii. e of the carapace is 
: about one and a half 
inches; and the length of the chelipeds is about three and a half inches. 
Its range is from Cape Cod to Florida, and it lives among the rocks, 
(Plate LXIV.) 
