1909. | OF THE THIRD TANGANYIKA EXPEDITION. 59 
Length of adult female 0°80 mm. 
Remarks.—In the form and armature of the caudal rami this 
form somewhat resembles a species recorded by Dr. Mrazek from 
small ponds at Bukoba, Victoria Nyanza, and named C. stuhl- 
manni. To judge from the figure given by that author, this 
form is, however, much more slender in shape, and the anterior 
antenne are composed of only 10 articulations, whereas in the 
present form they are distinctly 12-articulate, as in all the other 
species belonging to this group. 
Occurrence.—Only a single female specimen of this form has 
come to my notice. It was found in a sample from Tanganyika, 
taken 18/11/04 at Kala, eastern shore of the lake. 
29, CYCLOPS AGILOIDES, sp.n. (Plate XX. figs. 183-188.) 
Specific Characters.—FrMAuE. Body (fig. 183) rather slender, 
with the anterior division gradually widening anteriorly, front 
evenly rounded. Last pedigerous segment short, but rather 
broad. Urosome slender, considerably exceeding half the length 
of the anterior division ; genital segment somewhat dilated at the 
base. Caudal rami (fig. 188) of moderate length, about as long 
as the last two segments combined, and slightly divergent; outer 
edge armed with a row of very small denticles, which in the 
proximal part of the ramus are somewhat withdrawn from the 
edge and become so minute that they easily may escape attention ; 
innermost apical seta nearly twice as long as the outermost ; the 
two middle sete of moderate length and uniformly ciliated, the 
inner one exceeding the outer by rather more than one-third 
of its length. Anterior antenne rather slender, considerably 
exceeding in length the cephalic segment, and 12-articulate, the 
last three joints (fig. 184) with a distinct smooth longitudinal 
keel. Posterior antenne (fig. 185) of quite normal structure. 
Fourth pair of legs (fig. 186) with the spines of both rami finely 
denticulate, the apical ones of the inner ramus slightly unequal 
in size. Last pair of legs (fig. 187) with the spine of the inner 
corner well developed and coarsely denticulate. 
Length of adult female 0°90 mm. 
Remarks.—This form is closely allied to the European species, 
C. agilis Koch (= C. varius Lilljeborg), but differs in some 
particulars, especially as regards the form and armature of the 
caudal rami, so as more properly to be regarded as specifically 
distinct. 
Occurrence.—A. single female specimen (that described above) 
of this form was found in the above-mentioned sample from 
Victoria Nyanza, and two other specimens of apparently the same 
species weve derived from Tanganyika, the one from a sample 
taken 19/9/04 at Niamkolo, south end of the lake, the other in a 
sample taken 13/10/04 at Sumbu, south-western shore. 
30. CycLops EUACANTHUS, sp.n. (Plate XX. figs. 189-192.) 
Specific Characters—FrmMae. Body (fig. 189) comparatively 
