REPORT ON THE CUMACEA. 23 



Remarks. — This genus is chiefly distinguished from Leptocuma hy the body being 

 less elongate and not compressed, by the presence of a well-developed eye, by the second 

 pair of legs having the ischial joint obsolete, and finally by the penultimate pair of legs 

 in the female wanting the rudimentary exopodite present in the former genus. Of the 

 genus only a single species, Vaunthompsonia cristata, Spence Bate, was hitherto known. 

 The following new species from the Challenger Expedition is now added. 



4. Vaunthompsonia meridionalis, n. sp. (PL II. figs. 1-5). 



Spjecific Characters. — ? . Carapace shorter than the free segments of the trunk taken 

 together, with two short serrate crests on the posterior part of the dorsal surface, anterior 

 part unarmed. Pseudorostral projection broadly truncate at the tip, anterior edges 

 finely serrate and having three stronger serratures at the lower corner ; subrostral notches 

 distinct. Antero-lateral angles of carapace sharply produced, inferior edges strongly 

 serrate in the anterior part. Ocular lobe rather large, almost reaching to the tip of the 

 pseudorostral projection, with two small denticles in its anterior part. First pair of legs 

 shorter than in the typical sjsecies, with the three outer joints subequal. Posterior pro- 

 jection of last caudal segment triangular, with five slender spines on each side. Uropoda. 

 shorter than the two last caudal segments taken together, scape comparatively stout, inner 

 branch not longer than outer, with last joint small, scarcely half as long as first, both 

 strongly spinous on inner edge. Length, 10 mm. 



Remarks. — This new species may easily be distinguished from the typical form, 

 Vaunthompsonia cristata, Spence Bate, by the carapace having only two short diverging 

 crests on its posterior part, whereas the anterior part is quite smooth ; by the broadly 

 truncate pseudorostral projection and the distinctly marked notch beneath the same ; also 

 by the much shorter legs of the first pair, and finally by a rather different form of the 

 uropoda. 



Description. — The sole specimen before us is a young female, with the marsupial 

 pouch not yet developed. It measures in length about 10 mm. 



The general form of the body (see PI. II. figs. 1, 2) is nearly as in the typical species, 

 though somewhat less compressed. The anterior division tapers gradually backwards, 

 without being sharply defined from the posterior. 



The carapace is comparatively rather small, not attaining the length of the free 

 segments of the trunk taken together. The dorsal surface is but very little vaulted, 

 and exhibits posteriorly two short curved serrate crests diverging anteriorly, but for the 

 rest is quite smooth, without any trace of the strongly serrate longitudinal crest observed 

 in the typical species. The pseudorostral projection (see fig. 4) is very short, and broadly 

 truncate at the apex, with the anterior edges finely serrate, and having moreover three 

 much stronger denticles inferiorly. The notch limiting this projection inferiorly on each 



