KEPORT ON THE ISOPODA. 141 



The mandibles differed slightly in the two individuals ; in one specimen they are 

 much as is shown in fig. 10 of PI. X.; in the other specimen (PI. XVIII. fig. 12), the 

 denticulations along the inner margin are absent, their place being taken by a single 

 broad triangular process. 



The thoracic appendages, those that form the ambulatory limbs, are subsimilar ; one 

 of these appendages (the sixth of the right side) is displayed in fig. 11 of PL X. ; the 

 proximal joint has a stout spine on the outer margin, the following joints have shorter 

 but similar spines on the inner margin ; there is some difference in the number, size, 

 and position of these spines in the different pairs of appendages. 



The abdominal appendages (PL X. fig. 12), are all similar to each other with the 

 exception of the last pair ; they consist of a stout, basal joint, into which are articu- 

 lated a flattened, tongue-shaped endopodite and exopodite, the latter being the shorter; 

 there appear to be no setse present upon these appendages. 



The uropoda differ from these appendages in being somewhat stouter and in having 

 serrate margins fringed with long hairs; the endopodite reaches nearly to the end of the 

 -telson, the exopodite not so far; in one specimen the telson spine was rather shorter than 

 in the other, and the uropoda therefore reached quite to its extremity. 



Station I49h, off Cumberland Bay, Kerguelen, January 29, 1874; depth, 127 fathoms ; 

 bottom, volcanic mud. 



Station 149c, Royal Sound, Kerguelen; depth, 30 fathoms, from dredge; bottom, 

 volcanic mud. 



Anceus latidens, F. E. Beddard (PL XVIII. fig. 11). 



Anceus latidens, P. E. Beddard, Proc. Zool. Soc. Lond., 1S86, pt. i. p. 120. 



A single male specimen of this small Anceus was dredged in 7 fathoms in Flinders 

 Passage, North Australia. 



The specimen measures 2 - 5 mm.; it is of a rich brown colour, darker in parts. 



The head is squarish in outline, being about as broad as it is long ; the posterior 

 margin of the head forms two curves, meeting in the middle hue, where there is a deep 

 incision which is continued forwards for some way in the shape of a median furrow 

 between the two lateral convexities of the head, which are evenly convex above ; in 

 front of the eyes is a short, somewhat outwardly directed, spiny process, which marks the 

 antero-lateral boundary of the head. The anterior margin of the head is prolonged in 

 the middle line into three short blunt protuberances, of which the middle one is the 

 longest. The surface of the head is covered with numerous small rounded tubercles, 

 which are entirely absent for a space around the posterior median furrow. 



The first segment of the thorax is as usual extremely short, and does not extend any 

 further laterally than the lateral margin of the head ; the two following segments are 



