1903. ] IN THE ‘ CHALLENGER’ COLLECTION. 69: 
of “ Sergestes spiniventralis var.” from the “ West Pacific”; it 
has been suggested that the animal is allied to—or identical 
with—the Mastigopus of S. vigilaw Stimps., H. J. H., but the 
specimen could not be found. The collection contained one 
specimen determined as S. spiniventralis and labelled ‘Sidney to 
Wellington, 17. 6. 74” ; it measures about 7°5 mm. in length, 
and the naked part of the outer margin of the ext. br. of urp. is 
slightly more than one-fourth of its length. The specimen is in 
all probability a young MJastigopus of S. vigilax Stimps., H. J. H. 
SreRG. PROFUNDUS Bate, p. 428 (no figure). (Plate XI. figs. 3a, 
30.) 
Bate has referred two specimens to this species. He describes 
each specimen separately: the first of them, from Stat, 137, 
belongs to Petalidiwm, perhaps to P. foliacewm, and has been 
dealt with above. ‘The other specimen, from “Stat. 300, 
December 17, 1875; lat. 33° 42’ 8., long. 78° 18° W.; west of 
Valparaiso; depth 1375 fathoms; .... Trawled,” is a real 
Sergestes, related to S. inows Faxon, but differing in the shape of 
the rostrum. Having removed the first-mentioned specimen 
from the genus Sergestes, I should think it justifiable to apply 
the name S. profundus Bate to the last-named specimen, instead 
of proposing a new name. ‘The animal is quite membranous, 
and is crimson everywhere—a fact proving that it lives in the 
depth of the sea, and that its colour has been durable to the 
highest and most unusual degree. The posterior part of the 
abdomen is wanting, and the animal is on the whole so mutilated 
and flabby, that I would have omitted it if it had not been 
described by Bate; but for that reason I have thought it necessary 
to add some notes with two figures (Pl. XI. figs. 3a, 36). It 
agrees with S. mows Fax. as to the membranous quality of the 
skin and the posterior branchie, but differs from it in the shape 
of the rostrum, which is of moderate length, with the upper 
margin somewhat, and the lower margin partly, strongly convex, 
and distally it is produced in a moderately short spine (Pl. XI. 
fig. 36). (Unfortunately I have not seen any specimen of the 
gigantic species S. inous Fax., and can therefore not decide whether 
the specimen described by Faxon had the rostrum uninjured.) 
Supra-ocular and hepatic spines are wanting. The eyes (Pl. XI. 
fig. 3a) are black, comparatively small, somewhat shorter than 
broad, not half as long as the eye-stalks, and not broader than the 
distal end of the stalks. In the antenn. ped. the outer margin 
of the first joint is almost as long as that of the two distal joints 
together, therefore somewhat shorter than their inner margin ; 
the third joint is a little shorter than the inner margin of the 
second, and seems to be about three and a half times longer than 
deep. The squama does not reach the end of the antenn. ped., 
and the outer distal spine is well developed. According to Bate 
the part preserved measures 18 mm., and the probable length of 
the entire animal is 24 mm. 
