PRAWNS 261 
sandy shores it is translucent, pale in color, and often specked, closely 
resembling the sand, while on dark, muddy bottoms it is much darker. 
This is an edible shrimp, eagerly devoured by fishes; it is also gathered 
for the markets. The body of C. vul- 
garis is broad at the anterior end and 7 
tapers to a sharp point at the posterior 
extremity. A pair of broad, divided 
appendages on the cylindrical segment, 
which is next to the last on the abdomen, 
together with the sharp telson, form 
a fan-like swimming-tail. As in all 
shrimps, the antenne are long and have 
plate-like antennal scales at the base, 
which are fringed with hairs. The man- 
dibles are long. The movable finger of 
the chela is folded across the extremity 
of the claw. 
C. franciscorum, the California 
shrimp. This species is about three 
inches in length. It is distinguished 
from C. vulgaris by its larger size and 
by the greater length of the movable 
finger of the chela, which folds parallel 
to the side of the claw instead of across 
its extremity. Its color is light or dark 
yellowish-gray, mottled. This is the 
shrimp extensively gathered by the 
Chinese for commercial purposes. The 
shrimp-meat is dried and cured, and 
then separated by blowers very much _. 
as wheat is cleaned. It is exported to 
Eastern countries in great quantities, 
the value of the export being estimated at 
Crangon vulgaris, the common sand-shrimp; 
one hundred thousand dollars perannum. male natural size. : 
CREEPING FORMS: LOBSTERS AND CRAWFISH 
FAMILY ASTACOIDE 
Genus Homarus 
There are but three species of this genus, which is the most im- 
portant one of all the Crustacea. They are H. vulgaris of Kurope, 
H. capensis of the Cape of Good Hope, and H. americanus, which 
occurs on the eastern coast of the United States from Labrador 
to New Jersey. The lobster-fishery is one of great importance, 
and of such value that it is governed by stringent laws. The 
