EUCOPEPODA FROM TANGANYIKA. 827 
In two tubes, each containing a number of Nile specimens, the 
lengths vary from 6°2—9:0 mm. and from 8°8-11:7 mm. 
A careful examination showed the lateral torsion of the body 
to vary in direction, as was expected. Unfortunately, minute 
details as to the position of the parasites on the host are missing 
for the Nile material, so that it is impossible to test the accuracy 
of Quidor’s assumptions in relation to this species. The in- 
dividual from Tanganyika was, however, taken from the soft 
region at the junction of the pelvic fins,—a spot more nearly 
ventral than lateral. At the same time, it is hardly probable that 
the point of attachment was so strictly median as to preclude the 
possibility of lateral torsion in conformity with this view. 
Fig. 7 serves also to show how strikingly these parasitic forms 
may in turn be covered by other organisms. In this case, the 
latter are Vorticellids, which infest many of these Lerneids from 
the Nile to such a degree as to render difficult the study of their 
anatomy. Among a considerable number of specimens taken 
on a Polypterus senegalus, almost all are infested, some of 
them as markedly as the one photographed. The region where 
the Vorticellids are most thickly attached is about the junction 
of the thin anterior third of the body with the more dilated 
posterior portion. It seems highly probable that the manner in 
which these parasitic Copepods can be so densely encrusted by 
such organisms (other cases are referred to in the literature of 
the subject), is directly related to the peculiar fact that after 
fixation to their host they appear no longer to undergo ecdysis*. 
Occurrence.—Kituta, Lake Tanganyika, 24.8.04. From the 
soft region at the junction of the pelvic fins of a large Polypterus 
congicus. One specimen. 
White Nile. From the fleshy region at the junction of the 
pair of pectoral fins of a Polypterus senegalus. Highteen speci- 
mens, some of them incomplete, belonging to the collection of the 
British Museum. 
Fashoda, White Nile. Eight further specimens (one incomplete) 
from the British Museum collection. The only particulars stated 
are :—‘“ From Polypterus birchir, Fashoda.” 
Tt is interesting to note that this species of Zerneocera has 
been taken only on the Ganoid Polypterus, albeit on different 
species of that genus. , 
3. LERNHOCERA TEMNOCEPHALA, sp.n. (PI. I. figs. 8 & 9.) 
Description.—(Adult female.) Cephalic arms four, of unequal 
size. The dorsal arms are long and stout, and fork distally in 
a Y-shaped manner, terminating in rounded lobes. The ventral 
arms are quite short, slender and simple, being bluntly pointed 
at their ends. The body is almost straight, unsegmented and 
cylindrical. The anterior third or less is moderately slender, 
the body dilating gradually behind. Pre genital prominence 
* Of. Jungersen, Mindeskrift for J. Steenstrup, xvi, Copenhagen, 1914, p. 6. 
Proc, Zoou. Soc,—1914, No. LVI. 56 
