32 PROF. G. 0. SARS ON THE COPEPODA [Jan. 12, 
surface, but in some cases so near the shores as also to contain 
some material from the bottom. At the request of Dr. Cunning- 
ton, 1 have undertaken the examination of these samples, and 
have been much interested in selecting from them the several 
forms of Entomostraca therein contained. The Cladocera have 
been sent back to Dr. Cunnington, who desired to report on that 
group himself, whereas the Copepoda and the Ostracoda will be 
worked out by me. 
The material which has been placed in my hands for examina- 
tion, consists of a large series of tubes containing samples 
carefully preserved in formalin, and exactly numbered, both as 
to date and locality. To these samples were added some few 
smaller tubes containing Copepoda and Ostracoda, selected by 
Dr. Cunnington from some of the larger tubes. The greatest 
number of samples are derived from Lake Tanganyika. There 
are, however, a suflicient number of samples also from the two 
other lakes for instituting a comparison of the Entomostracan 
fauna of all three lakes. 
At the first sight, the samples looked rather unpromising, 
some of them being apparently quite devoid of Entomostraca, 
and others partly filled up with a compact muddy deposit which 
seemed quite unfit for investigation. Yet, by a very careful 
microscopical examination of all the tubes, I have succeeded in 
bringing to light a considerable number of different forms, both 
of Copepoda and Ostracoda, many of them apparently new to 
science. Some of the latter are of a quite particular interest, 
and will necessitate a renewed discussion about the origin of 
the fauna in the lakes. At the close of this Report some general 
remarks on this and other questions will be given. 
Owing to the great number of new and imperfectly known 
forms found in the samples, and which need to be described and 
figured, I have found it appropriate to divide my Report into 
two parts, the one treating of the Copepoda, the other of the 
Ostracoda. To these will be added a smaller paper on some 
larval stages of prawns, mostly found in the samples from Lake 
Tanganyika. The present part of the Report is wholly devoted 
to the Copepoda, which is by far the most richly represented 
group of Crustacea in the lakes. 
Systematic Nores AND DESCRIPTIONS OF NEW OR IMPERFECTLY 
KNOWN SPECIES. 
The Copepoda found in the samples belong to the three leading 
divisions: Calanoida, Harpacticoida, and Cyclopoida. The first- 
named division, as is well known, contains forms which, as a rule, 
lead an errant or sub-pelagic life, and of course will chiefly 
characterise the surface-plankton of the lakes. On the other 
hand, the forms belonging to the second division are exclusively 
bottom-dwellers. The third division contains both planktonic 
and true bottom-forms. 
