
*s RIJKS MUSEUM VAN NATUURLIJKE HISTORIE — LEIDEN. 167 

rated granules, of the same size as those of the inferior border; no trace 
of a transverse crest, only a few scattered hairs are to be seen. Fingers 
long, not gaping, coloured in red, with some large pits at both surfaces, 
especially in the case of the immovable finger; back of movable finger 
with a characteristic low keel, which is most distinct in the 
proximal half and gradually disappears distally; it is accompanied by 
irregular granules at both sides, but especially at the outer side, and is 
broken up towards its end into 4—5 very indistinct parts, marked by a 
transverse section. This last character is not mentioned, neither by de 
Man nor by Nobili; the latter author makes mention of two or three 
granules at the base of the keel, that in my specimen, however, is enti- 
rely smooth. 
The walking legs are short, very robust and entirely of the same 
shape as in Ses. taeniolata, though in the present species the dactyli are 
distinctly shorter and the propodites somewhat more slender. The mero- 
podites are twice as long as broad, transversely rugose (only minutely so 
in the case of the last pair), crenulate along the anterior margin and 
even at the distal fifth part of the posterior border. Carpo- and propodite 
together are longest in the case of the penultimate pair of legs. Dactyli 
always distinctly shorter than their respective propodites, acute, curved 
and hairy in the usual way. The propodites are furnished with hairs 
along the margins, but, as generally occurs in this genus, this hairiness 
extends farthest upward in the case of the first pair of walking legs 
and gradually diminishes in the other legs. 
As my specimen was a Q, as also those of de Man (1887 and 1892) 
and Nobili, the shape of the abdomen of the O must remain unknown. 
Dr. de Man very kindly lent me a specimen of the three young 
females, described by him in 1892. This small specimen, which was 
referred by the author to Ses. lafondi, though with some doubt, had a 
length of carapace of 18 mm.; the distance between the external orbital 
angles was 20 mm.; the proportion therefore 100: 111, intermediate be- 
tween what was found by de Man (1887) and by me in the case of the 
a 
large specimen of the Museum. In the young Q I further remarked, that 
the lateral margins of the carapace are slightly converging distally, not 
parallel, that of a second epibranchial tooth merely a trace is found, and 
that the median sinus in the free margin of the front is very shallow 
and broad, scarcely indicated; besides, each large transverse tubercle on 
each projection of the free margin, which tubercle is so conspicuous in 
the large Q, is replaced here by two minute granules, tipped with a hair. 
The keel on the upper margin of the movable finger is likewise present, 
though it is only distinct at the base and disappears very soon; also the 
12 
(23—V1—1917) 
