PORCEELANOPAGURUS—BORRADAILE. 
113 
Fig. 2.— Porcellanopagurus : side view 
of the specimen shown in Fig. 1, 
X 3. Ah, Abdomen; c, base of 
cheliped ; s, sixth abdominal 
tergum ; t, telson ; w, waist. 
and length, is represented in Porcellanopagurus by a short, deep, forward branch from 
the cervical groove above the third lobe of each side, and perhaps by a faint forward 
continuation. 
The substance of the dorsal plate, and of the armour of the first three pairs of legs, 
is very hard, porcellanous, and a little translucent, not at all like that of most hermit 
crabs, but its surface is roughened by many short, 
transverse ridges, and somewhat sparsely covered 
with hairs, placed in little rows, each in front of one 
of the ridges, an arrangement which, developed in s 
various degrees, is not uncommon in Eupagurinae. 
Below the projecting lobes of the back-plate, the sides 
of the cephalothorax (Fig. 2) are almost vertical, 
though rather low, and they and the hinder part of 
the thorax are soft, as in an ordinary hermit-crab. 
The post-cervical region is shorter and wider than in 
other Paguridae, and the concavity of its hinder 
edge is semicircular, not deep and narrow, as is usual in the family. In correspondence 
with this shortening of the region behind and above it, the hinder part of the linea 
anomurica is directed more downwards than usual. The “ line la ” of Boas branches 
as a Y at its upper end, the forward branch joining the linea anomurica opposite the 
cervical groove, the hinder branch behind the last side lobe. 
On the underside of the thorax (Fig. 3) the legs are set wider apart than in an 
ordinary hermit-crab, and the sternal series of plates is better developed, though in 
number and position its pieces faithfully resemble those of Eupagurus. The widely 
separated bases of the third maxillipeds are connected by a 
slender sternum, rather wider in the middle than at its ends. 
The two small sternal pieces on the segment of the chelipeds 
are fused, though their limits are still visible. They are not 
quite symmetrical, the left being rather more prominent than 
the right. The second pair of legs has a pair of large sternal 
plates. Behind them stands a transverse piece of good size, 
which appears to belong to the same segment as the two rather 
small ossicles at the bases of the third pair of legs. The sternum 
mxp 
Fig. 3.— Porcellanopagurus: 
third to sixth thoracic 
sterna of the specimen 
shown in Fig. 1, x 3. of the fourth pair of legs is a very narrow bar, placed more 
ch, Chehped; l 3, third dorsally than that of Eupagurus, on the anterior wall of a deep 
leg; mxp, base of third . . , , r . ’ , 1 - 1,1 
maxilliped furrow which separates from the cephalothorax a region con¬ 
sisting of the last thoracic segment together with the abdomen. 
On the hinder side of this furrow, thus seeming to belong to the abdomen, stands the 
sternum of the fifth pair of legs, which is also a very narrow bar. The oviducal opening 
is placed, not, as usual, on the ventral side of the coxopodite of the third leg, but on 
the hinder face of the joint, which is directed towards the furrow between the last 
R 2 
