A MONOGEAPH 



OF THE 



BBITISH 

 FREE AND SEMI-PARASITIC COPEPODA 



- 

 SECTION I. GNATHOSTOMA, Thorell (continued). 



Family 6. HAEPACTICID^E, Glaus (in part). 



BODY cylindrical, or, sometimes, flattened. Abdo- 

 men, in most cases, not sharply separated from the 

 cephalothorax. First pair of antennas short, composed 

 of few (4 10) joints, scarcely ever reaching beyond 

 the edge of the first body-segment ; in the male 

 forming on both sides a clasping organ. Second pair 

 2 4-jointed, bearing a secondary branch which is 

 usually small and made up of 1 4 joints. Mandibles 

 strongly toothed, provided with a palp which is either 

 simple, consisting of one or two joints, or more^omplex 

 and composed of a basal portion with two branches ; 

 in a few cases forming a laminated branchial appendage. 

 Maxillas usually well developed, consisting of a den- 

 tated cutting segment and a more or less complex 

 palp, which is made up of several setiferous digits 

 arranged in a somewhat radiated manner. First pair 

 of foot-jaws armed at the extremity with several strong 

 teeth, and on the inner margin with several (usually 



VOL. n. A 



