FROM THE GULF OF GUINEA. 35 



geknopftev Seitenspitzen." This form of filament appears to be peculiar to Augtqitilis 

 longicaudatns. Another species {AnguptUis TluUrwji) described in this lleport possesses 

 similar filaments, but the button-tops, instead of being round, are broadly crescent-shaped. 

 Not more than about half a dozen specimens of AugaptiUs longicaudatns were obtained 

 in the ' Buccaneer ' collections. 



AuGAPTiLis HECTicus, Giesbrecht. (PI. I. figs. 37-39, PI. II. figs. 1-4, 38-4i2.) 



1892. AnnaptUif! hecticus, Ciesbreclit, op. cit. p. ill, pi. 27. fig. 30; pi. 28. figs. 5, 9, IG, 30, 33, 37; 



pi. 29. fig. 18; pi. 39. fig. 45. 

 1892. Hemicalanus longisetosus, Scott (MS. name). 



Length, exclusive of tail-setse, 2-46 mm. ; cephalothorax elongate, slender, cylindrical, 



subtriangularin front, rounded behind ; anterior antennye, reaching beyond the extremity 



of the abdomen, 25-joiuted ; the right antenna of the male 18-jointed. Tlie proportional 



lengths of the joints are nearly as follows : — 



Male. 20 . 12 . 10 . i :^ . 1 ;^. . 1 3 . 12 . 56 . 20 . 22 . IS . 17 . 19 . 22 . 35 . 29 . 18 . 18. 



12 3 4 .-. li 7 8 9 10 11 12 13 14 15 16 1 7 18 19 20 21 22 23 24 25. 



Female. 20 .8 . 8 . 8 . S . 8 . 8 . 8 . 10 . 10 . 11 . 13 . 15 . 15 . ll . 13 . lT7]5TT2TTo7roTTO . 11 . 15 . is! 



In the male antennae the eighth joint is rather longer than the imited lengths of 

 the preceding four joints, and there is a distinct hinge between the fourteenth and 

 fifteenth joints ; the fifteenth bears at the proximal end a slender hair-like appeudao-e 

 which extends forward beyond the extremity of the joint. A densely plumose seta 

 springs from the lower terminal angle of the sixteenth joint, and from the upper 

 angle a rather long non-plumose spinous seta ; a second densely plumose seta, similar to 

 that on the sixteenth, springs from the upper terminal angle of the seventeenth joint. The 

 second and third last joints of the female anterior antennae and the left male antenna 

 are likewise fm-nished with one or two (?) plumose sette similar to those of the male 

 eighth antenna ; the antennae of both sexes are otherwise sparingly setiferous. The 

 secondary branch of the posterior antennae is fully half the length of the primary branch, 

 6(?)-jointed, both branches with long plumose hairs ; mandible styliform, the extremity 

 somewhat furcate, but one of the teeth nearly obsolete ; other mouth-organs as in 

 Hemicalanus longlcornis. Five pairs of swimming-feet in both sexes, all of them 2- 

 branched, with both branches 3-jointed ; the terminal spine of the outer branch of the 

 fourth pair has a row of minute tubercules along its exterior margin ; the inner margin 

 is ciliated. The middle joint of the outer branch of the right (?) fifth foot of the male 

 bears a stout, slightly curved process on the upper part of the inner margin ; the last joint 

 bears a short terminal spine, immediately behind which, on the inner margin, is a 

 moderately long plumose hair ; the last joint of the outer branch of the left foot bears a 

 long curved terminal spine, finely serrate on its inner edge ; both the inner margins are 

 furnished with several long plumose hairs which extend beyond the terminal spine of 

 the outer branch of the left foot. Abdomen in the male 5-jointed, in the female 4- 

 jointed ; the length of the segments in both are subequal. Caudal stylets in the male about 

 as long as the last two abdominal segments, and in the female about the length of the 



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