36 PROF. G, 0. SARS ON THE COPEPODA [Jan. 12, 
species, confluent with the preceding one; lateral corners rather 
projecting, and each terminating im a strong mucro pointing 
outwards (fig. 20). Urosome comparatively short and perfectly 
symmetrical ; genital segment nearly of equal width throughout 
and without any distinct lateral mucros; last two segments 
confluent, and combined not nearly attaining half the length of 
the genital segment. Caudal rami and sete: normal. Anterior 
antenne, when reflexed, scarcely extending beyond the tip of the 
caudal rami. Last pair of legs (fig. 21) with the inner ramus 
more produced than in the two preceding species, considerably 
exceeding half the length of the proximal joint of the outer, and 
tipped with two slender sete; claw of outer ramus of moderate: 
size and quite smooth ; terminal joint imperfectly defined at the 
base, inner apical seta extending to the tip of the claw. Ovisac 
comparatively small, with a somewhat varying number of ov: 
(from two to eight). 
Mate with the antepenultimate joint of right anterior antenna 
produced at the end to a slender mucroniform process nearly as. 
long as the penultimate joint (fig. 22). Last pair of legs (fig. 23) 
with the squamiform expansions of Ist basal joint simple, not. 
spiniferous ; 2nd basal joint of right leg without any projection 
at the end ; proximal joint of outer ramus terminating outside in 
an obtuse corner ; distal joint oblong oval in form, with a small 
scale-like projection on the posterior face just inside the lateral 
spine, the latter of moderate size and attached about im the 
middle of the outer edge; apical claw about twice the length of 
the distal joint and somewhat curved in the middle. Left leg 
with the outer ramus uniarticulate and somewhat spoon-shaped, 
terminating in a small digit accompanied by a short ciliated 
bristle ; inner edge evenly curved and finely denticulated; anterior 
face with a small ciliated lobule not projecting beyond the inner 
edge (fig. 24). 
Length of adult female 1-12 mm. 
Remarks.—This form has been described, though rather imper- 
fectly, under the above name by Dr. Mrazek im the above quoted! 
paper. It is nearly allied to the two preceding species, but 
evidently specifically distinct, being especially distinguished by 
the short and stout form of the body, the projecting lateral 
corners of the last segment of the metasome, and the structure of 
the last pair of legs in both sexes. 
Occurrence.—This form occurred rather plentifully together 
with D. galeboides in the above-mentioned sample from Victoria 
Nyanza. It was also found in another sample from the same 
lake, taken 20/4/05 in about the same region. Dr. Mrazek 
records it also from the island Djume. 
4, DIAPTOMUS SIMPLEX, sp.n. (Plate VIII. figs. 25-32.) 
Specific Characters—FEMALB. Body (figs. 25 & 26) rather short, 
with the anterior division regularly oblong-oval in form, gradually 
narrowed both in front and behind. Last segment of metasome 
