’s RIJKS MUSEUM VAN NATUURLIJKE HISTORIE — LEIDEN. 209 
Ses. pontianacensis de Man; in the other two species, Ses. jousseaumei 
Nobili and Ses. lanata Alcock, these lobes are more distinct. 
The subgenus Holometopus contains also one species with similar cha- 
racters: Ses. villosa A. Milne-Edwards. A small 9, which was provisionally 
referred by me to the genus Clistocoeloma, has been kindly examined by 
Dr. de Man, who informed me that it really belonged, at least most 
probably, to the present species. 
The species of Sesarma that resemble Clistocoeloma are, of course, to 
be distinguished from the latter genus by the orbit being open: the 
inner suborbital lobe does not touch the front, so as to exclude the outer 
antenna from the orbit, as occurs in Clistocoeloma. 
I have figured here the Museum specimen in order to point out some 
differences with the types, described at full length by de Man, and also 
to illustrate the remarkable resemblance with Ses. lanata Alcock (see II. 
Zool. “Investigator’’, Crust.; prt. 10, 1903, pl. 65 f. 4). In both species, 
indeed, the- carapace and the legs are covered with the same dense fur 
of short hairs and small tufts of somewhat longer hairs are scattered 
about. De Man has in a full-grown © exactly denoted the place of all 
the larger tufts. It may be ascribed both to the sex and to the youth of 
my specimen that in the first place the tufts of hair are all approxima- 
tely of the same size, and secondly that they are rather irregularly 
distributed and not in the design described by de Man, occupying the 
whole anterior half of the carapace. As de Man rightly remarked, the 
carapace and also the legs are found to be entirely smooth, after removal 
of the fur, but very finely punctate, owing to the insertion of the minute 
hairs. The different regions on the carapace are very faintly marked, the 
mesial furrow separating the median postfrontal lobes being the only one 
that is distinct; the grooves circumscribing the mesogastric area may also 
be traced ont, though more by the fact, that the dense fur of the carapace 
does not extend to this mesogastric area (nor to the anterior cardiac region), 
than by real grooves. The postfrontal lobes are very little developed, the 
median lobes being scarcely separated off from the lateral ones. The front 
is not vertically deflexed in my young specimen, nearly wholly vertical 
however according to de Man; the free margin is scarcely excavated in 
the middle and convexly arched, but I have seen no horizontal projection, 
as observed by de Man. As to the lateral margins of the carapace, the 
latter author has described them as being wholly without teeth, diverging 
distally until the bases of the second pair of walking legs. As shown in 
my figure I have removed the hairs near the left margin of the carapace, 
in order to show its course. It is true, that I found the external orbital 
angle to be feebly developed, scarcely protuding, but behind it I noted 
