92 CYAMID A. 
~ 
segments being not wide apart at the lateral margins, and 
by the possession of two slender filiform branchiz at- 
tached to each side of the third and fourth segments of 
the body. The species represented by Mr. Spence Bate 
(Plate 58, fig. 3) is from the Cape of Good Hope, and 
possesses a very strong tooth near the extremity of the 
fourth joint of the second pair of legs. We presume, 
notwithstanding its locality, that it is identical with 
M. Roussel de Vauzeme’s species. The branchial ap- 
pendages of the males are longer than those of the 
females. In the species before us the anterior pair are 
furnished at the base with a single pointed appendage, 
whilst the posterior pair have this appendage doubled, its 
branches being rather unequal in size; these appendages 
exist in the female in the modified form of large flat- 
tened plates, or valves, extending beneath the middle of 
the body. These plates are concave, pedunculated, 
fringed at the edges, and formed of a double transparent 
membrane: thus constituting a sac without an external 
orifice. These plates, lying upon each other, serve as a 
pouch, within which the eggs are deposited, and the 
young hatched. Some uncertainty has been entertained 
as to the real nature of the branchial appendages, which 
have been regarded as simple stems, false legs, pseudo- 
branchize, vesicles without determinate use, and organs of 
respiration ; but the direct observation of M. Roussel 
on the living animals has demonstrated that they are 
branchial canals in communication with the dorsal vessel, 
and of a membranous texture, whilst the appendages at 
their bases in the male are differently organized, being 
crustaceous, and unfitted for organs of respiration; and 
the plates of the ovigerous pouch in the female are also 
destitute of branchial canals, and consequently unable to 
perform the functions of gills. 
