286 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
examined forms to 53. They belong to four different families — Lysia- 
nassidae, Pontoporeiidse, Corophiidae, and Gammaridae, the last being 
most abundant. The collection described included 15 new species. 
New Species of Branchipus * * * § — Dr. A. Alcock describes and figures a 
large and beautiful form — Brancliijpus ( Streptocephalus ) hengalensis sp. n., 
— found in flooded rice-fields near Calcutta. It is most closely related to 
Br. rubricaudatus Klunzinger from Arabia, and, through the female, to 
Br. torvicornis Waga from Warsaw, The body is rather over an inch 
long. The antennae of the male are more than half as long as the body ; 
those of the female form a pair of short broad leaf-like lobes, bending, in 
repose, over the eyes, like curtains. 
North American Freshwater Ostracods.t — Mr. R. W. Sharpe gives 
an account of North American Cytheridae and Cyprididae, discussing 
22 species. Fourteen of these are new to America, and about a dozen new 
to science. Two of these new forms belong to the genus Limnicythere , 
itself new to America. The systematic part of the paper is preceded by 
an interesting account of local and seasonal distribution prepared by 
Mr. C. A. Hart. 
Olfactory Setse of Cladocera.J — Mr. D. J. Scourfield gives a short 
account of the structure, number, and arrangement of the peculiar little 
setae on the first pair of antennae in the Cladocera, usually considered 
to be olfactory. It appears that in the females the number of such setae 
on each antennule is characteristic of families and groups of families. 
Thus the Polyphemidae have 5, the Holopedidae 6, and the remaining 
families, namely Sididae, Daphnidae, Bosminidae, Lyncodaphnidae, Lyn- 
ceidae, and Leptodoridae, 9 olfactory setae in each tuft. The number in 
the males is sometimes the same as in the females (Daphnidae), but often 
greater (Lynceidae). As regards the arrangement of the setae, cases are 
mentioned where it is possible to distinguish closely allied species 
simply by the relative lengths and positions of these minute structures. 
Some Manitoba Cladocera.§ — Mr. L. S. Ross has the honour of 
writing the first systematic paper on the Entomostraca of Manitoba, and 
it is on this account that we notice his contribution, which deals with 
30 species, including Ceriodaphnia acanthinci , which is new. 
Pycnogonids.|| — M. E. Topsent reports on the Pycnogonids collected 
in 1894-6 in the North Atlantic by the Prince of Monaco. The collec- 
tion was very small, comprising only two species, Colossendeis gigas 
Hoek and C. leptorhynchus Hoek. The latter species was found by the 
* Challenger 5 only in the South Pacific and Indian Oceans. 
Annulata. 
Ovum Centrosome in Chsetopterus.f — Mr. A. D. Mead has convinced 
himself that the asters and centrosomes in the ovum of Chsetopterus 
pergamentaceus arise by a modification of the cytoplasmic reticulum. 
* Journ. Asiat. Soc. Bengal, lxv. (1896) pp. 538-9 (1 pi.), 
t Bull. Illinois Lab. Nat. Hist., iv. (1897) pp. 414-81 (10 pis.), 
j Journ. Quekett Micr. Club, vi. (1896) pp. 280-88 (1 pi.). 
§ Amer. Nat., xxxi. (1897) pp. 293-303 (1 fig.). 
11 Bull. Soc. Zool. France, xxii. (1897) pp. 106-7. 
1 Journ. Morphol., xii. (1897) pp. 391-4 (3 fig3.). 
