IgIo. | S. Kemp: Notes on Decapoda. 179 
Gennadas bouvieri, Kemp. 
Gennadas bouviert, Kemp, Proc. Zool. Soc., 1909, p. 726, pl. 
Ixxiv, figs. 1—4; pl. Ixxv, figs. 6 and 7. 
St. 198.—North-east of Ceylon, 8° 55’ N., 81° 17’ 30” E., 764 
fathoms. One female, about 25 mm. 
This specimen agrees closely with the description of the type. 
The only important difference lies in the proportional length of 
the joints of the third pair of peraeopods, where the merus is only 
very slightly shorter than the carpus. Except for the fact that no 
spermatophores are inserted, the thelycum its practically identical 
with that figured in 1909 (pl. xxv, fig. 6). 
G. bouviert was found by the ‘Challenger’ west of Manila and 
north of New Guinea. 
Gennadas carinatus (Smith). 
(Plate xiv, figs. 4—9.) 
Benthesicymus ? carinatus, Smith, Rep. U.S. Fish Comm. for 
1882, 1884, p. 396, pl. x, figs. 6 and 7. 
Gennadas carinatus, Alcock, Desc. Cat. Ind. Macrura, 1go1, 
p. 46. 
Gennadas carinatus?, McGilchrist, Ann. Mag. Nat. Hrst., 
March, 1905, p. 236. 
St. 128:-—Off, Cy Comorin, .6° 58° N.,..77° 26 50) E: 
fathoms. One male, 130 mm. 
St. 306.—Off Travancore, 9° 20’ N., 75° 24 
One female, 148 mm. 
, 9O2 
/ 
E., 930 fathoms. 
This large species is of great interest and, although the two 
specimens in the Indian Museum have already been recorded by 
Alcock and McGilchrist, a fresh description drawn up on the lines 
of Bouvier’s recent work may be found useful. 
I have followed Alcock in placing the species in the genus 
Gennadas, though, in point of fact, it is almost exactly intermediate 
in character between that genus and Benthesicymus. In habit, 
however, the two genera appear to be quite distinct, for Gennadas, 
as far as at present known, is entirely pelagic, whereas Benthesi- 
cymus lives on the bottom. Now in carinatus the joints of several 
of the appendages are greatly flattened and expanded and closelv 
resemble those of the former genus, and this modification, which is 
doubtless correlated with a free-swimming existence, has induced 
me to retain the species in its present position. 
Alcock has, indeed, suggested that it might be best to regard 
Gennadas as a subgenus of Benthesicymus, but from a_ practical 
point of view this cannot be recommended. It must be remem- 
bered that it is only in the present case that any difficulty arises 
in allocating the species to one or other genus. 
