* 2 RECORDS OF THE AUSTRALIAN MUSEUM. 
very fully investigated by Nebeski,* but for this reference again 
I am indebted to Stebbing’s report. 
In addition to our present species Stebbing has described another 
new species Cerctpus sisrnithi , taken during the Challenger Expe- 
dition at Kerguelen Island, f 
In the following detailed description of the various parts of the 
animal I have omitted all those parts where I had nothing to add 
to Mr. Stebbing’s description. 
Head and body.— The head is produced anteriorly into a sub- 
acute rostrum between the bases of the antenme, much in the 
same way as is shown in Mr. Stebbing’s figure of Cerapus sisrnithi, 
but in none of my specimens have I noticed the rostrum to be 
“carinate” as it is drawn and described by Mr. Stebbing in G. 
JUndersi. (See figures A and B.) 
The relative lengths of the various segments of the. pereion of 
the female agree well with Stebbing’s description, but in the male 
they are quite different. In this (see fig. B.) the first segment is 
about as long as the head, the second is slightly longer, anteriorly 
it is slightly narrower than the first segment, but about the middle 
it suddenly widens to twice this width thus giving attachment to 
the large and powerful second gnathopoda ; the third segment is 
considerably shorter than the second and is also narrower anter- 
iorly but it widens posteriorly ; the fourth is shorter again than 
the third, as wide anteriorly, but narrowing posteriorly ; the fifth 
segment which is so long in the female, is only a little longer than 
the fourth and not so long as the third ; the sixth is subequal to 
the fifth in length and breadth; the seventh is as broad but shorter. 
Upper Antennce — These agree on the whole with Stebbing’s 
description, but the first joint of the peduncle is not “ much longer 
than the second joint”; it is usually about the same length and in 
large specimens may even be somewhat shorter. The flagellum 
may contain as many as seven joints, usually there are more than 
four, the number given in Stebbing’s description. (See fig. a. s.) 
Lower Antennce . — These also differ in a few details. The fourth 
joint is not “ dilated at the base,” nor “ abruptly broader than the 
preceding joint ” in any of the specimens that I have examined, 
indeed the fourth joint is usually narrowed a little at the base 
and it articulates with only a portion of the end of the third joint 
so that the articulation is not very strong and the fourth joint is 
very freely movable upon the third. (See fig. a. i.) 
* “ Beit rage zur Kentniss dor Amphipoden der Adria 1 ” — Arb. Zool. 
Inst. Wien. Bd. III. (See Stebbing’s Report on the “Challenger” 
Ampbipoda, p. 518.) 
f Report on the “ Challenger” Amphipoda, p. 1158, PI. cxxiv. 
