900 
THE VOYAGE OF H.M.S. CHALLENGER. 
of the Paguridea appear to have a very wide geographical range ; thus, a species apparently 
identical with the well-known Pagurus striatus, Latr., of the Mediterranean, was taken at 
two Stations off the Philippines, and Petrochirus granulatus, Olivi, a native of the West 
Indies, was dredged at Simon’s Bay, Cape of Good Hope. The collection contains several 
specimens of an interesting species, with a regularly segmented and calcified abdomen, show- 
ing a transition between the Paguridea and the Thalassinidea, trawled at Station 163a, 
Fig. 330 .—Ptychogaster milne-edivardsi, n. sp. ; natural size. Magellan Strait, 400 fathoms. 
off Twofold Bay, Australia (120 fathoms). In many respects this singular Crustacean 
agrees with the description of A. Milne-Edwards’ recently established genus Pylocheles, 
from the ‘ Blake ’ expedition, but differs strikingly in habit, as all the Challenger 
specimens occurred in a free condition. At Station 285, in the South Pacific, at a 
depth of 2375 fathoms, one of the most interesting forms in the collection was taken. 
The single specimen, type of a new genus and species ( Tylaspis cinomala ) is essentially 
