138 ZOOLOGISCHE MEDEDEELINGEN — DEEL III. 





to an extreme by the remarkable Platychirograpsus') de Man from 
Gabun, in which the palm is elongated proximally beyond the carpal 
joint into a complete elbow. The upper margin of the palm in S. bocourti 
is feebly marked off and provided with three or four nearly parallel, 
longitudinal granular ridges; the inner surface presents a number of small 
largely separated and irregularly disposed tubercles. De Man says that 
there is no transverse granulated ridge at this inner surface, and in our 
older specimen from Borneo I could indeed observe no trace of it, but 
in the specimen of Balikpapan and in another specimen of the Zoological 
Museum of Amsterdam, originating from Deli, there is a row of 4—5 
large granules and some smaller ones running from the base of the 
mobile finger in a curved line towards the proximal large tubercle on 
the cutting margin of the immobile finger. The upper margin of this 
mobile finger shows rather numerous sharp tubercles, irregularly placed ; 
the finger itself, looked at from above, is, according to de Man, some- 
what distorted or S-shaped, but I own, that I have not found anything 
irregular in its course. The inner surface of both fingers is perfectly smooth. 
The walking legs are short; the meropodites much broadened, only 
about twice as long as broad; carpo- and propodite are only slightly 
hairy and the dactyli are rather long, scarcely shorter than the propo- 
dites, covered with bunches of hairs, and falciform. 
In the abdomen of the male I noted a remarkable difference in the 
shape of the penultimate and 
of the 4th segment between 
the specimens at my disposal. 
In the older specimen from 
Borneo and that from Deli 
the abdomen (f. 2a) is rather 
narrow and the posterior mar- 
gin of the penultimate segment 
is nearly exactly twice the 
em b length of this segment, as in 
Fig. 2. Sesarma bocourti A. M. Edw. the two specimens measured 
Abdomen, Magn. 2. by de Man (1. c. p. 171), but 
the specimen of Balikpapan (f. 2b) has a much broader abdomen, the 
penultimate segment of which is nearly 3 times as broad at the posterior 
margin as long. Besides, in the first form the lateral margins of the 
4th segment are slightly concave (f. 2a), in the latter form they are 
very slightly convex (f. 2b). It must remain undecided whether this 
1) Mitt. naturhist. Mus. Hamburg, Bd. 18, 1896, p. 95—110, pl. 2, pl. 3 f. 4c. 
