I913.| - SS. Kemp: Crustacea Stomatopoda of the Indo-Pacific Region. 95 
with at least the tips movable; no submedian denticles, never more than three inter- 
mediate denticles. Ventral process of uropods consisting either of two well-formed 
spines, inner longer than outer, or vice versa and with an additional spine or spine 
and spinules on inner margin near base. 
In structure there do not appear to be any marked secondary sexual differences. 
One species, the very curious and rare P. ferusacci from the Mediterranean, 
disagrees in several important particulars from the diagnosis given above and seems 
in fact to be almost exactly intermediate in character between Pseudosquilla and 
Squilla. The principal features in which alliance with the latter genus is shown are (i) 
the well marked cervical groove, (ii) the presence of the posterior reflected part of 
the marginal carina of the carapace and (iii) the presence of fine submedian, inter- 
mediate and lateral carinae on the abdomen. ‘The form of the telson is, however, 
similar to that found in Pseudosquilla and the characters afforded by the ventral 
process from the basal segment of the uropods seem to indicate a position near 
P. empusa, P. cerisit, P. lessoni and their allies. 
Another outstanding form of doubtful position is P. stylifera ; this species is 
known from the Australian and Chilian Coasts and there is some evidence to show 
that different races inhabit these widely separated localities. 
Of the twelve species of Pseudosquilla that are known, nine have been found 
within the area with which this memoir is concerned and two of these, P. ciliata and 
P. oculata, have also been taken in the Atlantic. Two forms, P. certs and P. ferus- 
saci, appear to be restricted to the Mediterranean and one, P. Jessoni, is known only 
from the Pacific Coast of America. 
In Pseudosquilla ciliata and its immediate allies a curious process springs from 
the dorsal aspect of the antennal protopodite. This consists of a flat elongated plate, 
directed forwards, and provided inferiorly with a deep vertical keel. In some cases 
this process seems to afford useful specific indications. 
The species of Pseudosquilla seem to prefer rough ground, inhabiting coral reefs, 
oyster-beds and similar situations. They are invariably found in shallow water, the 
greatest depth from which any species is known being 20-23 fathoms (P. ciliata, 
Bigelow). 
The carinae on the telson, in species which possess the full complement, consist 
of a median and five pairs and for these I have used the terms ‘submedian,’’ 
“intermediate,” “‘first lateral,’’ “‘second lateral’’ and -‘‘marginal.’”’ This ter- 
minology is the same as that employed in the case of Odontodactylus (see text- 
fig. 4, p. 12), but the ‘‘ second submedians’’ are never found in the present genus. 
Key to the species of Pseudosquilla. 
I, Dactylus of raptorial claw with teeth on its inner margin. 
A. Basal process of uropods terminating in two large teeth, its inner margin 
smooth. 
I. Telson with only three carinae on either side of median crest, the 
first and second laterals being absent. 
