THOMPSON: METAMORPHOSES OF HERMIT CRAB. 151 
The majority of the larvae handled belonged to E. longicarpus and 
it is fitting therefore that this species should be described rather than 
E. annulipes. But the following account is applicable to the latter 
and to the other species of the genus also. 
Like many other Decapods, Eupagurus longicarpus is crepuscular 
and during the day a majority of individuals remain buried in the 
sand or congregated in the shade. They are omnivorous and must 
glean very closely, as they pick up bits of gravel or detritus from 
the bottom and brush them over between the maxillipeds. They 
also toss sand — usually with the smaller cheliped only — to the 
mouth parts, brush it between them and let the grains fall again in 
it is in this manner that they 
obtain the diatoms and foraminifera, which are found in the stomach 
and intestine. But although the food is thus very largely diatoma- 
ceous, no sort of vegetable or animal matter is refused. 
The asymmetry is dextral. The chelipeds and the two following 
pairs of limbs are larger on the right than on the left side. The 
abdomen is spirally twisted to the right and only the sixth segment, 
telson, and first segment are heavily calcified. The remainder and 
major portion is soft and bloated. The boundaries of the segments 
are lost, except dorsally where the posterior borders of the terga 
can be traced, and show that the fourth and fifth segments are elon¬ 
gate, while the second and third are shortened. The sternum of 
the first segment or peduncle is indistinguishably fused with the 
sternum of the last thoracic segment. The peduncle bears no 
appendages and the four succeeding segments have no pleopod on 
the right side. On the left side, the female has a large biramous 
pleopod on the second, third, and fourth segments and a smaller 
pleopod with a minute internal ramus on the fifth (pi. 6, fig. 24); 
while the male has a pleopod similar in shape to the most posterior 
of the female’s series on the third, fourth, and fifth segments, but 
no pleopod on the second segment (pi. 6, fig. 25). The uropods 
are alike in the two sexes and the left is the larger (pi. 7, fig. 31 a ). 
The greater development of the female’s pleopods is probably 
correlated with their use during the breeding season when the eggs 
are borne on the hairs of their borders. It must not be hastily 
assumed, however, that the pleopods of the male have no function. 
"W hile watching adolescent crabs that were inhabiting straight glass 
shells I have noticed that their pleopods were at times waved in the 
a continuous stream. Probably 
