1926] Schmitt, Crustaceans Collected by the Congo Expedition 65 
The range of size of the kasaiensis eggs is not unlike that of stuhl- 
mann (=decorser). In fact de Man himself remarks of what he calls a 
local race of decorsec from Kidada (op. cit., pp. 17-20), ‘‘ Les oeufs ont com- 
munément la méme taille que chez la variété Decorsei, mais parfois, 
comme dans les exemplaires Nos. 88 et 95 du Tableau, ils étaient plus 
grands, comme chez la variété Kasaiensis, une variabilité observée aussi 
dans la variété Kwamouthensis.”’ 
With respect tode Man’s retention of Macrobrachium (Palzemon) 
lenziz, on the face of the evidence presented, it would still seem to be but 
one of the growth stages in the development of MW. dux. His female 
lenzi is certainly a dux, and the males too compare in a most satisfying 
way with the M. duz series when their tabulated measurements are taken 
into consideration. Regarding M. dux var. congoensis our conclusions 
are in accord, and de Man’s case for his newly described variety tenui- 
carpus of this species appears no better than did the original one for the 
variety congoensis. Between the tabular measurements of the variety 
tenuicarpus and those of lenziz for specimens of approximately the same 
size, there is also a close correspondence, surely unmistakably corrobora- 
tive of their identity (cf. de Man, op. cit., tab. E., No. 2, and tab. G, 
No. 30). : 
The single or double row of large spines on the internal border of the 
palm, distinguishing M. dux from M. lenziz as a character, is ‘‘more or 
less distinct’’ and was so originally described by de Man (1911, p. 230). 
In a seemingly unquestionable series of dua specimens, it does not appear 
to be an easy matter to say definitely in all cases whether there is but 
one row or, sometimes, as it seems for part of the way at least, possibly 
two rows of larger spines on the internal border of the palm. 
I also still remain to be convinced that Macrobrachium jamaicense 
var. herklotsii is not identical with M. vollenhoveni (cf. de Man’s meas- 
urements of the young male of the latter, op. czt., p. 51, with the male 
No. 13 in his tabular summmary of var. herklotsiz, tab. H.). The differ- 
ence in the relative slenderness of the last three pairs of legs to my mind 
is not sufficient ground for considering the two as belonging to distinct 
specie, to say nothing of their being placed in different subgenera. 
Miss Rathbun has already stated our views on the subject of the 
generic names of Palemon and Macrobrachium (Annals of the Institute 
of Jamaica, I, No. 1, 1897, p. 45), but as carcinologists still seem to be at 
loggerheads over the matter, I venture this restatement of the case: 
(1). “The type of the genus Palxmon was specified by Latreille 
in 1810 (Consid. Génér. Crust., p.421) as P.squilla; the genus was thus 
