SURFACE COPEPODA OF THE GULF OF IMANNAR. 225 



(?. Total length, 1 • 1 mm. 



Proportional lengths of cephalothorax and abdomen 2:1. 



The head and first thoracic segment are fused completely 

 and thoracic segment 4 and 5 partially so ; the postero-lateral 

 border of the fifth segment is, as in the female, armed with 

 a large backwardly projecting spine. The romided anterior 

 " forehead " terminates ventrally in a bifid rostrum composed 

 of long fleshy processes. 



The abdomen consists of five segments having, with the 

 furea, the following relative proportions : — 16 : 25 : 24 : 24 : 11 : 

 21. Segments 2 to 4 inclusive are armed round their posterior 

 borders with a series of triangular spines. 



The first antenna on the right side is modified to form a 

 grasping organ ; it is composed of twenty joints, having the 

 following relative proportional lengths : — 



The knee-joint is situated between segments 18 and 19, and 

 the " Endabschnitt " consists of two joints only, segments 

 19 and 20 and 21 to 23 being respectively fused together. 

 Segment 10 bears a long spine-hke seta, and segments 12 to 16 

 are all armed with needle-hke spines ; the seventeenth segment 

 bears a lamellar process on its anterior aspect ; both segments 

 of the knee-joint are armed with lamellar plates, that on the 

 proximal segment being armed with needle-hke teeth, while 

 that on the distal is unarmed. 



The Second Antenna. — The two rami are of nearly equal 

 length ; the last joint of the exopodite is swoUen and nipple- 

 shaped. The endopodite is of the usual type. 



The Second Maxilliped.—Bsisal 1 is three-fifths as long as 

 broad ; it bears four setae on its anterior border and carries a 

 single stout spine-like seta distally ; basal 2 is beset with fine 

 hairs proximally, and about the middle of its length bears 

 three stout setse ; it is about twice as long as broad. The 

 terminal portion of the appendage consists of the usual five 

 segments. 



