BELONGING TO THE GEXEEA BKADYA AND ECTINOSOMA. 427 



Aiiteuute similar to those of Bradya. 



Mandibles usually cleft at the apex and armed with strong teeth ; mandibular palp 

 similar to that of Bradya. 



Anterior foot-jaws usually composed of two robust joints, and armed at the extremity 

 with two moderately stout and elongate spiniform claws and a few setae ; the first joint 

 is also furnished Avith two or three setiferous marginal processes. Second joint usually 

 larger than the other. 



Posterior foot-jaAvs elongate, slender, three-jointed, and in structure resembling those 

 of Bradya. 



Five pairs of thoracic feet similar to those of Bi^adya. 



Remarks. As already pointed out in. the description of the genus Bradya (ante, p. 420), 

 the difference in the structure of the anterior foot-jaws is the most important and the 

 most constant difference between Ectiuosoma and Bradya, and so great is the resemblance 

 otherwise between species belonging to these two genera that frequently we have found 

 it almost imj)ossible to distinguish without careful dissection whether the specimen that 

 haj)peued to be under examination belonged to the genus Ectinosoma or to Bradya. 



EcTiNosoMA Saesi, Bocck (1872). (PL 36. figs. 14, 2G, 42 ; PI. 37. figs. 1, 21, 38, 52 ; 

 PI. 38. tigs. 10, 22, 32, 51.) 



1872. Ectinosoma Sarsi, Boeck (2), p. -io. 



1880. Ect'iHosuma spinipes, Brady (3). vol. ii. p. 9, pi. xxxvi. figs. 1-10. 



1885. Ectinosoma Sarsi, Poppe (9), p. 198. 



1888. Ectinosoma spinipes, Scott (12), p. 239. 



1892. Ectinosoma Sarsi, Cami (6), p. 152. 



1893. Ectinosoma spinipes, I. C. Thompson (16), p. 18, pi. xviii. fig. 8. 



Description. Length 1"2 mm. (^/j- of an inch). Body, seen from the side, slender 

 fusiform ; rostrum prominent, blunt-pointed, and reaching to near the extremity of the 

 antennules. 



Autennules short, robust, 5-jointed, gradually tapering towards the distal end, and 

 strongly setiferous. The proportional lengths of the joints are nearly as shown in the 



formula : — 



No. of the joints : 1.2.3.4.5 



Proportional lengths : lo 12 9 (riO ' 



Antennse large, 3-jointed, joints subequal in length, the terminal joint furnished 

 with a number of stout sette, coarsely plumose on the upper margin, and with several 

 short spines ; secondary branch elongate, 3-jointed, arising from the end of the 

 first joint of the primary branch; the last joint of the secondary branch is equal to 

 nearly twice the combined lengths of the other two joints; the first two joints are each 

 armed with a spiniform seta, that of the first joiat is short, but that of the second is 

 elongate and coarsely plimiose on the upper edge ; the last joint bears two long terminal 

 setre, also plumose on the upper edge (PI. 37. fig. 1). 



Mandibles armed Avith a fcAV strong irregular-sized teeth and a small plumose seta ; 

 the basal joint of the palp, Avhich is nearly equal in size to the mandibles, bears 



SECOND SERIES. — ZOOLOGY, VOL. VI. 57 



