“ TERRA NOVA” EXPEDITION. 
/9/p/.<?4-?r 
lit, -or 
150 
Remarks. —The specimens described above as belonging to C. lev is, G. M. 
Thomson, diminish, although they do not altogether obliterate, the difference formerly 
stated to exist between that species and this as regards the dorsal outline of the 
carapace. The specimens now recorded tend to depreciate another of the characters 
separating the two species, inasmuch as the oblique ridge of the carapace becomes so 
merged in the general rugosity of the surface as to be, in certain specimens, altogether 
indistinguishable. Nevertheless, the specimens are at once easily separable from those 
referred to <levis, even when occurring in the same gathering, by the strong pitting 
of the surface of the carapace. The pits are so large and so close together that 
the intervening surface forms an irregular raised network and the carapace may 
be described either as pitted or as reticulately rugose. This sculpturing is, of course, 
to be distinguished from the minute reticulate texture which the whole of the 
exoskeleton shows, as it does in many other Cumacea. 
The remaining differences formerly enumerated between this species and C. levis 
concern chiefly the proportions of the distal segments of the first leg and of the 
peduncle of the uropod. In both cases careful measurements of specimens in the 
present collection show differences of the same kind, though somewhat less than those 
stated in my former description; the dactylus of the first leg is three-fourths as long 
as the propodus as against a proportion of four-fifths or a little more in C. levis, and 
the peduncle of the uropod is longer than the last somite bv nearly one-fourth in the 
female and one-third in the male. In C. levis the peduncle is only about one-sixth 
longer than the last somite. 
The double lateral ridge of the last thoracic somite, mentioned only for the male 
sex in the original description, is present also in the female. 
18 . Cyclaspis coelebs, n. sp. Fig. 5. 
Oeeurre/ire. - Stations 133, 135, and 136. Spirits Bay, near North Cape, New 
Zealand. Plankton, at 20 metres, 3 metres, and surface. Five males (inch holotype). 
Description .—Adult male. Total length 5 • 6 mm. 
Resembling in general form the male of ('. thomsoni but with the carapace shorter 
and deeper, its height being about two-thirds instead of little over half its length. 
Surface of carapace obscurely and irregularly rugose or pitted. On either side, just 
below the lateral limits of the frontal suture, is a broadly rounded prominence, 
somewhat elongated antero-posteriorly, very conspicuous when seen from above, 
occupying the position of the anterior upper tubercle of C. elegans. Behind the middle 
of the carapace is a faintly marked oblique ridge inclined backwards and downwards 
and dying out below in the general rugosity of the surface. A curved ridge running 
backwards from the antennal tooth is very prominent. The ocular lenses are 
conspicuous ; three very large ones form a triangle dorsally and a pair are set close 
together at the tip of the ocular lobe, while three others on each side, overlapped by 
the upper margin of the lateral plate, are only indistinctly seen. 
