23 
with descriptions of two new species. 
of a small pea, of an oval form and very convex, rounded at the 
base and somewhat pointed at its apex, under which anteriorly it 
is deeply notched. The shell is smooth, shining, and of a pale 
yellow or cream colour (dry). 
Two or .three specimens were brought home by Mr. Arthur 
Adams, Assistant Surgeon Royal Navy, attached to H.M. Ship 
^ Samarang,-’ who dredged them during the late voyage of that 
vessel in the South Atlantic Ocean. They had as well as the 
preceding species been preserved dry, and from the long time 
they had been kept so, it was almost impossible to dissect the 
animal. However by steeping them in spirits of wine for some 
time, I succeeded in obtaining the body of the animal sufficiently 
entire to be able to ascertain the genus. The anterior antenna 
(fig. 2) consists, as in the preceding species, of four joints, the 
three last having numerous pretty long plumose setae springing 
from the upper edge, and the last being terminated by a tuft of 
similar but longer setae. The natatory foot (fig. 3), as in the 
other species, consists also of a very large basilar joint which 
gives origin to two branch es ; the upper of which consists of one 
very long joint and six very short ones, from the base of each of 
which issues a long plumose seta. The oviferous foot (PI. VII. 
fig. 4) resembles very much that of the preceding species, being 
cylindrical, and beset at its upper extremity with spines. The 
jaws and tail resembled very much the same organs in C. Mac- 
Andrei, but the body of the animal was too much decomposed 
to allow me to see them sufficiently accurately to be able to figure 
them. 
Godeheu de Riville, in his paper on the Luminosity of the Sea, 
published in 1760 in the third yol. of the ^Memoires pour les 
Savans Etrangers,^ describes a small Entomostracan which must 
belong to this genus. Sailing along the coast of Malabar, when 
in 8'^ 47' N. lat., and in 73° E. longitude of Paris, the sea was 
observed to be unusually and most brilliantly luminous. Having 
had his attention previously directed to this interesting phseno- 
menon, Riville determined to ascertain the cause. The water all 
round the vessel and to a considerable distance from it was white 
as snow, and in the wake of the ship innumerable star-like bodies 
of a still brighter lustre sparkled on the surface of the agitated 
surf. He had some water drawn up from alongside, and he then 
observed numerous bright sparkling spots in the bucket in which 
it was contained. Pouring it out upon apiece of linen, numbers 
of small bodies still giving out light were observed adhering to 
the surface of the cloth. They were alive, and resembled, he says, 
those small insects called in France Puces d’eau.” The body 
of the animal was contained in a little shell which was transpa- 
rent, and resembled in form an almond cleft on one side and 
