116 A HISTORY OF RECENT CRUSTACEA 
character. Considering the tolerably ruthless manner in 
which the crab gathers the constituents of its costume, 
one need not wonder at their needing a little emollient 
ointment. Under the circumstances their natural ten- 
dency to adhere might otherwise remain for some time 
dormant. | 
Chorinus aculeatus, Milne-Edwards, as depicted on the 
preceding page, is suggestive of a wardrobe provided with 
a truly enviable number of pegs. In regard to a closely 
related species, Chorinus longispina, de Haan remarks that 
to the hooked sete of the thorax and legs marine odds and 
ends adhere so closely that they can scarcely be removed 
without damaging the sete. He is thinking only of man’s 
rude handling, for, however remorseless such a crab may 
be towards its surroundings, we may feel assured that its 
deft fingers will do no violence to the well-appointed furni- 
ture of its own carapace. 
Pisa, Leach, 1813, is open to the suspicion of being a 
synonym of Arctopsis, Lamarck, 1801. ‘There are several 
species of this genus in various parts of the world. The 
two known in English and Irish waters occur also in the 
Mediterranean and have a considerable range north and 
south. These are Pisa tetraodon (Pennant) and the species 
which Bell calls Pisa Gibbsit1, Leach, a name which must 
be wrong, whatever other is right. Miers with some hesi- 
tation adopts for it the name Pisa (Arctopsis) tribilus 
(Linn.). 
Nawia, Milne-Edwards, 1854, is narrowly distinguished 
from Pisa by the accessory spinules of the two-horned 
rostrum. Naaia hystriz, Miers (see Plate IV.), was ob- 
tained by the Challenger at Amboina. 
Lissa, Leach, 1815, is a genus apparently near to Pisa, 
but with a rostrum consisting of two truncate laminar 
horns side by side, which are somewhat wider at the ex- 
tremity than at the base. It was formed for the Mediter- 
ranean species Lissa chiragra (Fabricius), which is deep 
red in colour, and has the legs so covered with protuber- 
ances that its specific name, meaning ‘ gout in the hand,’ is 
not inappropriate, although it so happens that the hands 
