CRUSTACEA FROM THE FALKLAND ISLANDS. 359 
1910. Pariphimedia Stebbing, Mem. Australian Mus. vol. iv. 
pt. 2, p. 584. 
1912. a Chilton, Tr. Roy. Soc. Edinb. vol. xlviii. 
p- 487. 
H. Rathke’s [phimedia and G. M. Thomson’s Panoplea, 
according to Chevreux, are distinguished from this genus chiefly 
by the following characters :—the cutting-edge of the mandibles 
not denticulate, the principal lobes of the lower lip emarginate 
on the inner edge, the palp of the first maxille two-jointed, the 
inner lobe of the second maxille carrying a single series of 
sete, the second gnathopod not completely chelate, and the 
telson apically emarginate. 
It would, I think, be inconvenient to press the first of these 
characters as essential to either of the genera mentioned ; but 
both are rather sharply separated from Pariphimedia by the two- 
jointed palp of the first maxilla, in strong contrast with the feeble 
single-jointed structure in Chevreux’s genus, which makes an 
approach to that found in Odius Lilljeborg. 
In adding a second species to the genus, I feel fairly sure that 
it is identical with the scantily-described Jphimedia normant 
Cunningham, which has so long remained obscure. But the 
addition tends to weaken the original definition, inasmuch as the 
telson has a neat little convex emargination which helps to dis- 
tinguish it from P. integricauda, in which, as the specific name 
declares, the telson is unincised. By a curious contrariety the 
upper lip, which is there slightly emarginate, is here simply 
convex. The mandibles in the two species essentially agree, the 
trunk tapering to a fine point, the distal part of the margin 
minutely denticulate, the molar represented by a projection with 
no triturating surface, the palp well developed, its second joint 
much the longest, the third curved, setose. Neither mandible in 
P. norman has a secondary plate, so far confirming the sugges- 
tion which I have earlier made, that the same is the case in 
P. integricauda. While it may be said that the distal lobes of 
the lower lip are in both species undivided, it will be seen that in 
P. norman there is a marked tendency towards apical division. 
PARIPHIMEDIA NORMANI (Cunningham). (Pls. LV. & V.) 
1871. Iphimedia normanit Cunningham, Tr. Linn. Soc. London, 
vol. xxvii. p. 498, pl. 59. fig. 7. 
1906. 5 a Stebbing, Das Tierreich, vel. xxi. p. 217. 
This species, by the notable features of its mouth-organs and 
enathopods, clearly belongs to the family Acanthonotozomatide. 
But of spine-like processes on the back, which so many members 
of that family exhibit, it is singularly devoid. Only the third 
segment of the pleon makes a show of relationship in this respect 
by an upturned postero-lateral angle and high up on the side 
a still stronger upturned tooth. The two preceding segments 
have the postero-lateral angle produced into acute points, and 
