4 DR. "W. T. CALMAX OX NEW OE EAEE 



the carapace the lateral keel is distinct only in its middle portion, and its posterior end 

 curves slightly upwards ; it is not developed on the first free somite, and only a 

 slight lateral elevation indicates its place on the posterior thoracic somites ; below it 

 on the carapace is a slightly marked elevation, not forming a distinct keel, and behind 

 the above-mentioned notch on the dorsal surface is a slight transverse elevation, not 

 sharply defined. Antennal tooth triangular. Basis of first legs a little shorter than 

 the remaining segments together. Uropods longer than the last two somites together, 

 the rami two-thirds as long as the peduncle. Endopod of two segments, the 

 proximal nearly four times as long as the distal, with five spines on its inner edge ; 

 distal segment with two spines. 



Immature Male. — Total length 2-6 mm. 



Eesembling the female, except that the carapace is still smoother, the lateral keel 

 being the only one distinct. 



Occurrence.— GwVL of Siam, " Koh Kam, 5 fathoms, 6/2/00." Th. Mortensen Coll., 

 Copenhagen Museum. Co-types in British Museum. 



BoDOTRiA siMiLis, sp. n. (Plate I. figs. 4-9.) 



Description of adult Female. — Total length 2'15 mm. 



Closely resembling in general characters B. arenosa Goodsir. Carapace less than 

 tw^o-sevenths of total length. Median dorsal keel rather prominent on the thoracic 

 somites. Lateral keel well-marked and straight on carapace and on all except the 

 last of the free thoracic somites. No distinct ridge below lateral keel on side of 

 carapace. Antennal tooth triangular. Basis of first legs a little shorter than the 

 remaining segments together. Uropods longer than the last two somites together, 

 the exopod about three-fourths as long as the peduncle and a little longer than the 

 endopod. Endopod unsegraented, with six small spines on the distal part of its 

 inner edge, the last close to the slender terminal spine. Exopod with two unequal 

 slender terminal spines and a series of setae on the inner edge. 



Adult Male. — Total length 2-8 mm. 



There is a distinct ridge on the side of the carapace below the lateral keel. The 

 latter is distinct on all the free thoracic somites. Basis of first legs a little longer 

 than the remaining segments together. Kami of uropods subequal and two-thirds as 

 Ion"' as the peduncle. Endopod with twelve spines on the inner edge. 



Eemarks. — This species resembles very closely the B. arenosa of British and 

 Norwegian Seas. It is distinguished by its very much smaller size, by the shorter 

 basis of the first legs, and by the longer rami of the uropods. 



Occurrence. — Gulf of Siam, " Between Koh Mesan and Cape Liant " and " Tung 

 Kaben." Th. Mortensen Coll., Copenhagen Museum. Co-types in British Museum. 



