A HISTORY OF SUSSEX family of the Nebaliidas is sometimes thought worthy of being placed by itself in a separate section called the Leptostraca. The Entomostraca, whether of the sea or of the fresh water, have not yet been subjected to any extensive or elaborate investigation for this county. In the gymnophyllous division of the Phyllopoda, that is in the peculiar group which have their leaf-like limbs not covered by a carapace, the graceful fairy shrimp, Chirocephalus diaphanus, Prevost, was recorded by Dr. Baird in 1850 as taken near Brighton by C. Ager.^ Recently the species has been again discovered in Sussex by G. H. Maxwell-Lefroy, Esq., a student at the Cambridge zoological laboratory, and now Government Entomologist in the West India Province. In sending me specimens, my friend Mr. J. J. Lister, F.R.S., writes : ' The locality is recorded in Harmer's Museum records as a small pond on " High and Over " (one of the downs, I take it) to the right of the Alfrestone Road, rather more than one mile out of Seaford. The pond is said to be dry from April to September, and the specimens most abundant in March and early April ; but these were collected in December, 1899.' It is a pleasant experiment to take soil from the dried-up floor of such a pond, and pour water over it in a finger-bowl, for the excellent chance of being able in two or three weeks' time to watch the development and growth of fairy shrimps, or, failing them, of other interesting entomostracans. Of the Cladocera Brady mentions taking Daphnia obtusa, Kurz, in a pond at Burpham, Sussex, and D. prop'mqua, Sars, in ponds at Arundel and Angmering of the same county. But he agrees with M. Jules Richard in regarding D. propmqua as only a variety of D. obtusa, and he practically agrees with Sars and with Lilljeborg in considering that D. obtusa with the short apical process can scarcely be distin- guished from the common D. pulex, which sometimes though not always has a long one.^ The Natural History of Hastings in 1888 records under ' Daphniads ' 'Z). magna, Strauss; D. vetula, Miill., common'; and under ' Lynceidae ' Chydorus sphcericus, Miill., common.^ Of the Daphniids Dapbiia magna, Straus, in 1898 was transferred by Brady to a new genus, Dactylura, which Lilljeborg in 1901 rejects as not needed. Lilljeborg points out that Daphnia pennata, O. F. Miiller, 1785, includes D. magna along with D. pulex, but because of this con- fusion he rejects Miiller's earlier name.* D. vetula is now known as Simocephalus vetulus (O. F. Miiller). Chydorus spharicus (O. F. Miiller) should be referred not to the Lynceidas, a family name required else- where, but to the Chydorids. Of Ostracoda the Hastitigs Natural History records Cypris tristriata, Baird, and 'C } fusca, Strauss.'^ Brady and Norman make the former a synonym of C. virens (Jurine), ' one of the commonest and most widely distributed of British fresh-water species,' " and by the latter is > British Entomostraca, Ray Society, p. 54.
- Nat. Hist. Trans. Northumberland, pt. 2, xiii. 224, 226.
s Second Supplement (1888), p. 16. * Cladocera Suecla, p. 71.
- Nat. Hist. Hastings, Second Supplement, p. 16. * Trans. Roy. Duhlin Soc. ser. 2, iv. 74.
264
