DK. W. M. TATTEESALL : AMPHIPODA AND ISOPODA. I 
Distribution. Ceylon, the Maldives and Laccadives, and tlie coast of Africa 
(Walker) ; South Africa (Stebbing) ; Australia and Tasmania (Haswell & 
Stebbing) ; New Zealand (Chilton) ; French Oceania (Chevreux). 
Remarhs. From the publislied descriptions and figures, this species would 
appear to be subject to great variation in the antennae, antennules, first and 
second gnathopods, fifth perseopods, and in the size and extent of the 
serrations on the margins of the pleon and its epimeral plates. 
These facts have led me to ascribe all the four specimens in this collection 
to the same species, notwithstanding the differences and the extraordinary 
dimorphism in the second gnathopods of the only male specimen. 
In the large female specimen, 10 mm. in length, the dorsal surface of the 
pleon is microscopically sliagreened. The teeth on the posterior margins of 
the first three segments are longer and coarser than in the smaller specimens, 
and there is a seta alternating with every tooth. The epimeral plate of the 
first pleon segment has two teeth on the lower border and eight on the hinder 
border, or ten teeth in all. The second pleon segment has five teeth on the 
margins of the epimeral plate, and the third segment fourteen teeth. It is 
not easy to decide where the lower and hinder margins meet. The antennal 
peduncle is equal in length to the anteunular. The accessor}' flagellum of 
the antennule has seven joints and the main flagellum twenty-five. The 
flagellum of the antenna has fourteen joints. The hinder lower corner of 
the second joint of the fourth and fifth perseopods is prolonged into a spine, 
as figured by Chevreux (1907) for specimens from French Oceania. 
In the smaller specimens the teeth on the dorsal border of the first three 
pleon segments are shorter and finer than in the larger specimen. The 
epimeral plates of the first two segments of the pleon have one or two teeth 
ou the lower border but none on the hinder. The third segment of the pleon 
has six teeth on the hinder border and two on the lower border of the 
epimeral plate. The flagellum of the first antenna has seven joints and the 
accessory appendage four joints. The flagellum of the second antenna has 
from 15-21 joints. Tiie hinder lower corner of the second joint of the 
fourth and fifth perteopods is much less produced than in the large 
specimen, and is more like the typical form. 
The male specimen presents a striving dimoi'phism in the second gnatiio- 
pods. The right one is of the normal type, the palm rather oblique and 
furnished with two flat-topped teeth. It is not so robust as in the specimens 
figured by Chevreux from French Oceania, and the palm is more oblique and 
not transverse. But Chilton describes specimens from New Zealand which 
appear to agree with mine. The second gnathopod on the left side is quite 
different. The propodus is larger and more robust, the palm very oblique 
with no prominent tooth marking its edge, but with a very strong obtuse 
