58 PROF, G. 0, SARS ON THE COPEPODA [Jan. 12, 
thirds of the length of the anterior division; genital segment 
conspicuously dilated at the base. Caudal rami (fig. 180) ex- 
ceedingly slender and elongated, almost attaining the length of 
the remaining part of the urosome ; outer edge perfectly smooth, 
seta of this edge attached at only a short distance from the end 
and accompanied at the base in front by a transverse row of four 
small denticles ; innermost apical seta about the length of the 
outermost ; the two middle sete rather slender and uniformly 
ciated, the inner one exceeding the outer by about one-third of 
its length. Anterior antenne 12-articulate and of moderate 
length, being about as long as the cephalic segment, their outer 
joints (fig. 177) conspicuously longer than in ©. levimargo. 
Natatory legs of normal structure. Last pair of legs (fig. 179) 
extremely small, with the spine of the inner corner very short. 
Ovisacs about as in the two preceding species. 
Length of adult female 0°82 mm. 
Remarks.—This form at the first sight looks very like the 
Huropean species, C. macrurus G. O. Sars. On a closer com- 
parison, however, it is found to differ in the comparatively more 
slender anterior antenne, and more particularly in the structure 
of the caudal rami. In the European species the seta of the 
outer edge is much more remote from the end, and in front of it 
four denticles occur, which do not form a transverse row, as in 
the present species, but are arranged along the edge. Moreover, 
the innermost apical seta is considerably longer than the outer- 
most, and the spine of the inner corner in the last pair of legs 
more fully developed. 
Occurrence.—Some few specimens of this form were found in a 
sample from Tanganyika, taken 18/11/04 at Kala, eastern shore 
of the lake. One female and two male specimens of apparently 
the same species occurred in a sample from Lake Nyasa, taken 
13/6/04 in the Anchorage Bay. 
28. CYCLOPS RARISPINUS, sp. n. (Plate XIX. figs. 181, 182.) 
Specific Characters. —FumMaue. Body (fig. 181) comparatively 
short and stout, with the anterior division ovoid in form and 
narrowly truncated in front. Last pedigerous segment with the 
lateral parts somewhat produced and clothed with fine hairs. 
Urosome slightly exceeding half the length of the anterior 
division, and having the genital segment rather much dilated at 
the base. Caudal rami (fig. 182) much shorter than in the three 
preceding species and also less narrow, scarcely widening at the 
end: outer edge armed with a short row of about eight small 
denticles not extending to the middle of the ramus, inner edge 
finely ciliated in its proximal half ; innermost apical seta nearly 
twice as long as the outermost; the two middle set rather slender 
and uniformly ciliated, the inner one exceeding the outer by rather 
more than one-third of its length. Anterior antenne moderately 
slender and distinctly 12-articulate. Legs apparently of normal 
structure. Ovisacs comparatively small and scarcely divergent. 
