30 T. V. HODGSON. 
The pleopoda are four paired structures occupying the entire area below the caudal 
shield. Each pleopod consists of a very road and short basal joint bearing an 
exopodite and an endopodite, which lie over one another, the exopodite being the outer 
or more ventral structure. The exopodite of the first gill is the largest and coarsest 
in structure, forming an operculum over the rest. The plate is obliquely divided into 
two by a suture, and its stout straight inner margin is thickly fringed with fine sete ; 
the outer margin, which is rounded anteriorly and wide, tapers slowly to a blunt point 
and is fringed with rather long plumose sete. The endopodite is much more delicate, 
rather smaller, having no sets whatever, and it is not divided, though its outer margin 
bears a conspicuous notch where the division should be. The posterior gill is shorter 
and broader than the preceding one; the exopodite is obliquely divided, but the only 
setee it bears are a few of both kinds at the distal extremity ; the endopodite resembles 
that of the first gill. 
The uropoda are attached to the caudal shield where the edge becomes dentate ; 
the basal joint is short, expanded distally, and prolonged on the inner side into a 
spinous process. The exopodite is two-jointed, the terminal one being scarcely half as 
long as the other, pointed, and having two serrations on the outer side and two spines 
on the other. The endopodite is a little longer than the first joint of the exopodite, 
and its external margin is serrate and has a few sete in addition ; the internal margin 
is also serrate but only distally. 
Two males and fragments of two others, sex uncertain, were taken by the 
‘Discovery’ in lat. 67° 21’ 46"8., long. 155° 21' 10” E., 254 fathoms, bottom mud. 
The trawl passed over a patch of stones probably dropped by some wandering iceberg, 
and brought up so large a quantity of these that the specimens were very severely 
damaged, and the trawl had to be slit up completely to save anything. 
Both Dr. Studer’s and Mr. Beddard’s descriptions of Serolis cornuta are defective 
in many points. The niceties of specific discrimination as now understood were 
altogether unknown in Eights’ day. Almost invariably the defects of previously 
published descriptions are those of omission rather than commission, and going through 
them exhaustively with the ‘ Discovery’ specimens before me, I have no hesitation what- 
ever in definitely stating that the ‘Gazelle’ and ‘Challenger’ specimens are immature 
specimens of Serolis trilobitoides Eights, and that the ‘Discovery’ specimen is only 
just arriving at the adult stage. 
CYMODOCELLA. 
Pfeffer (11), pp. 109-110 ; Hansen (7), p. 107. 
The following definition of this genus is by Dr. Hansen— 
Both sexes similar without processes. 
Distal part of the abdomen somewhat produced, with the lateral walls bent 
strongly downwards and inwards, constituting rather a long tube open 
at both ends and with a slit on the lower surface. 
