420 MESSES. T. AND A. SCOTT— EEVISION OF THE BEITISH COPEPODA 



The following is a list of the species described in this memoir, arranged in alphabetical 

 order : — 



Genus Bradya. 



Bradya elegans, sp. n., p. 422. 

 „ fusca, sp. n., p. 424. 

 „ hirsuta, sp. n., p. 423. 

 „ minor, sp. n., p. 425. 

 „ similis, sp. n., p. 424. 

 „ typica, Boeck, p. 421. 



Genus Ectinosoma. 



Ectinosoma armiferurn, sp. n., p. 434. 



„ atlanticum, Brady & Robertson, 



p. 437. 





Ectinosoma curticorne, Boeck, p. 430. 

 „ trythropn, Brady, p. 431. 



„ gracile, sp. n., p. 429. 



Herdmani, sp. n., p. 432. 



longicorne, sp. n., p. 439. 

 „ melaniceps, Boeck, p. 434. 



„ Normani, sp. n., p. 435. 



„ propinquum, sp. n., p. 428. 



pygmceum, sp. n., p. 433. 



Sarsi, Boeck, p. 427. 



tenuipes, sp. n., p. 436. 



tenuireme, sp. n., p. 439. 



3) 



Genus Bradya, Boeck (1872). 



Description. Body elongate, fusiform ; abdomen not distinctly separated from the 

 thorax. The antennules are usually short and composed of live to eight joints. 



The antennae are 3-jointed, and the secondary branches of the antennae are 2- to 

 3-jointed, usually slender, and of variable lengths. 



The mandibles are each furnished with a well-developed palp, composed usually of a 

 stout basal joint bearing two 1-jointed branches, one of which is apical and the other 

 marginal. 



The maxilla? are well developed. 



The anterior foot-jaws are of considerable size and composed of five joints ; the first 

 tw^o joints are large and the articulation between them is strongly hinged ; the first joint 

 also bears three setiferous marginal processes ; the three terminal joints are usually very 



small. 



The posterior foot-jaws are smaller than the anterior and are 3-jointed; the end- 

 joint is shorter than the preceding one, and is usually provided with three apical setae. 



The first four pairs of swimming-feet are all somewhat similar in structure; both 

 branches are composed of three subequal joints, and the outer are usually somewhat 

 shorter than the inner branches. 



Fifth pair small, composed of two joints, a basal and a secondary joint. 



Hemm^ks. The most important diflFerence between Bradya and Ectinosoma is to be 

 found in the structure of the anterior foot-jaws. In Bradya the anterior foot-jaws are 

 composed of five distinct joints, the first two of which are usually large, while the other 

 three are very small ; the articulation between the first two joints is strongly hinged, 

 and in all the " spirit " specimens examined by us the large second joint (together with 

 the three small terminal joints) is bent at, or nearly at, a right angle to the first joint. 

 Moreover, the secondary branches of the antenna? vary in the number of joints from two 

 to three, whereas in all the specimens of Ectinosoma examined by us the secondary 



