268 MARINE INVERTEBRATES 
for any other hermit common on our coast, since it has the very distinc- 
tive feature of white longitudinal stripes on the ambulatory feet. The 
chelipeds are about equal, rough with tubercles, and the tips have 
smooth black edges. Body and feet are quite hairy. The color is 
brown and white. 
Genus Pylopagurus 
This genus is represented in Southern waters by several species, 
One of the most characteristic of them lives in Dentalium, the 
tooth-shell. The outer surface of the right hand is formed to 
close the shell. All the ambulatory feet and the very small left 
hand fold beneath, leaving only the flat surface of one hand ex- 
posed to view. Another species lives in a shell covered with 
polyzoans. 
FAMILY CENOBITIDE 
Genus Cenobita 
C. diogenes. This large hermit-crab, found in Florida and in more 
southern waters, inhabits the beautiful pearly shell of Livona pica. It 
lives on land a part of the year, but spends the breeding season in the 
water. It can be distinguished by its land-roaming habits, its large left 
cheliped, very stout walking-legs, and compressed eye-stalks. This spe- 
cies climbs the hills, but is more frequently met with in low, shaded, 
marshy places. (Plate LIX.) 
FAMILY HIPPIDE 
Genus Hippa 
Hi. talpoida. This animal, commonly known as 
the ‘‘sand-bug,” differs greatly in appearance from 
a crab. When the appendages are folded under the 
carapace it somewhat resembles an egg, the body 
being ovate, about half as broad as long, and the 
sides forming a nearly regular curve. The carapace 
is about one and a half inches long, convex, yellowish- 
white, and nearly smooth. The abdomen is long and 
pressed under the body, reaching nearly to the front. 
The eyes are minute and on the ends of long, slender 
stalks. The antenne are plume-like and about as 
Hippa talpoida, the long as the carapace. Hippa lives on sandy beaches 
sand-bug. at or near low-water mark, exposed to the action of 
_., the waves. It burrows with great rapidity into the 
loose and shifting sands, using the short and stout second, third, and 
fourth thoracic legs and the appendages of the sixth abdominal segment 
