REPORT ON THE CiRRIPEDIA. 59 



as the extremity of the third segment of the hinder ramus of the sixth cirrus, and are 

 ten-jointed, with a long pedicel. A row of very minute bristles is placed round the upper 

 margin of each segment, a somewhal longer tuft is inserted on the slender terminal 

 segment. 



Penis distinctly segmented or ringed. Short and very thick, with numerous slender 

 and isolated hairs, and a tuft of longer and stouter ones at the extremity. 



This species was found on the spines of a deep-sea Echinid Phormosoma hopla- 

 cantha, A. Ag. ; it was dredged during the cruise of the Challenger at Station 164a, 

 June 13, 1874; lat. 34° 13' S., long. 151° 38' E. ; depth, 410 fathoms; bottom, grey 

 ooze. Off New South Wales. 



Affinities. — It is possible that Alepas tubulosa, Quoy et Gaimard, is the same species 

 as the one collected by the Challenger. However, I prefer to consider the latter as a 

 different species, because the former has a distinctly tubular orifice, which is not the case 

 with my Alepas pedunculated ; and as regards other characteristics, the imperfect descrip- 

 tion published in the voyage of the "Astrolabe" leaves us quite in the dark. The form of 

 the capitulum with the slightly protuberant orifice no doubt shows a certain resemblance 

 to Alepas cornuta, Darwin. But the latter species is easily distinguished from mine — 

 (l) by the flattened projections along the carinal margin of the capitulum; (2) 

 by the rudimentary condition of the inner rami of the fifth and sixth cirri ; and (3) by 

 the large number of the segments of the posterior cirri. 



Scalpellum, Leach, 1817. 



Darwin's diagnosis is as follows : — Valves twelve to fifteen in number ; latera of the 

 lower whorl four or six, with their lines of growth generally directed towards each other ; 

 sub-rostrum very rarely present ; peduncle squamiferous, most rarely naked. Filamen- 

 tary appendages none ; labrum with the upper part highly bullate ; tropin various ; 

 olfactory orifices more or less prominent ; caudal appendages uniarticulate and spinose, 

 or none. 



This at least is the diagnosis for the hermaphrodite and female specimens, to which 

 diagnosis Gerstacker adds that the mandibles have three or four teeth, that the first 

 cirrus is seated far distant from the second, and that the second and third cirri have 

 the rami more thickly clothed with spines than the three posterior cirri. 



The males (Darwin) are parasitic at or near the orifice of the sack of the female or of 

 the hermaphrodite; thorax enclosed within a capitulum, furnished with three or four 

 rudimentary valves, or with six perfect valves; peduncle either short and distinct, or 

 confounded with the capitulum; sometimes mouth and stomach absent, and cirri non- 

 prehensile; sometimes mouth and cirri normal. 



Darwin (1851) has described six recent species belonging to this species; Gerstacker 



