
124 RECORDS OF THE S.A. MUSEUM 
Colour yellow. 
Length to 7 mm, 
Juveniles, about 2:3 mm. in length, are similar to young of tribulis, but the 
carapace lacks a post-ocular dorsal projection; the characteristic ridging of the 
carapace is pronounced, but the posterior median elevation is low and as usual 
the appendages are stouter and relatively shorter than in the adult. 
The peduncle of the uropods is stout, much shorter than the rami, which 
are relatively wider than in older examples. 
Loc. South Australia: St. Vincent Gulf. New South Wales: Jervis Bay. 

Fig. 44. Cyclaspis usitata, subadult female (New South Wales); A, lateral view; B, cara- 
pace from above (X 19). 
Material attracted to light at Brighton, October 22, 1941, and again in No- 
vember 1943, consisted largely of subadult and adult females, all of which had 
recently moulted. They were almost all flaccid, the integument transparent with 
black pigment spots, and not at all or scarcely calcified, although in some indura- 
tion was proceeding and the very coarse pitted patterning characteristic of the 
exsculpta group was noticeable. These adult females are smaller than the type 
(7 mm. as against 10 mm.) and about equal in size to the subadult female from 
New South Wales which is figured (fig. 44 A and B). The marsupium is fully 
developed but contains no eggs; the ovaries are swollen with large ova (approx. 
0-4 mm.) easily visible through the transparent integument as large, bright yel- 
low masses (fig. 48, A). It may be that, as in some other Crustacea, mating 
occurs at this period. 
Some of the specimens discussed above, females and juveniles, were attracted 
by green light on November 22, 1941, at 8.15 p.m., and it is worthy of note that 
at the same place and time Cumacea flocked around the green light in much 
greater numbers than the ever present Amphipoda, which appeared in over- 
whelming numbers when a red light was used. A ‘‘white’’ lamp produced prac- 
tically the same result as the green. 
As noted under mawsonae, the male of that species swarmed at Brighton on 
October 13, 1941, a week prior to the swarming of the females of usitata. 
