It is desirable to call attention to the identification of the larvæ of the Trichopterous insects Agraylea multipunctata and Oxyethira costalis, by Messrs. Kenneth J. Morton and Robert McLachlan. The perfect insects were bred from larvæ collected in this district, as referred to in the “Entomologists’ Monthly Magazine,” May and June, 1886. So many problems in the life history of insects, having aquatic larvæ, remain unsolved, that it is desirable that microscopists should pay more attention to this subject.
ARACHNIDA.
The curious Diving-bell Spider, Argyroneta aquatica, is found in the pools at Sutton Park; and a great variety of species of the Water-Mites is generally distributed. Mr W. Saville Kent reports that several specimens received from this district are new to science.
Tardigrada, viz., Macrobiotus Hufelandii, and other species, may be found almost everywhere, if carefully looked for amongst damp moss and decaying algæ.
CRUSTACEA.
In this class should be mentioned the freshwater Crayfish, Astacus fluviatilis, not of course a microscopic organism; but if it were omitted here it would not appear in any of the other reports. This species is fairly distributed in most of the smaller brooks, in the canals, and larger reservoirs, but is not so abundant or so large as it is on the lime formations round Oxford. Two other large microscopic species of this class, the freshwater Shrimp, Gammarus pulex, and the water Wood-louse, Asellus vulgaris, are always present, the former busy in its office of scavenger in the sandy bottoms of the brooks and ditches, and the latter climbing about, like a monkey, amongst the water weeds, investigating the mass of living and decaying organisms with which the weeds are clothed.
Entomostraca.
The members of this sub-class are also to be found everywhere, but it is desirable to call special attention to the discovery for the first time in Great Britain of the wonderfully transparent Leptodora hyalina, at a visit of the Birmingham Natural History and Microscopical Society in 1879, to the Olton Reservoir, near Solihull. It has since been found in many localities, and is very abundant in the summer and autumn in the Warwick Canal and several reservoirs. Hyalodaphnia Kahlbergensis is very generally found with it. Argulus coregoni is found in the Birmingham and Warwick Canal. It had only been discovered in Great Britain previously in the tanks of the Royal Aquarium at Westminster, which, of course, are not used for British fish exclusively. The Fairy-shrimp, Chirocephalus diaphanus, is found in only one locality in the district, near Knowle. A few specimens of the very rare Lynceus acanthocercoides were found near Bewdley, and amongst other local finds may be mentioned Moina rectirostris, Macrothrix roseus, and Ilyocryptus sordidus.