A HISTORY OF WARWICKSHIRE 



gills attached to the trunk-legs several appendages of the pleon supply 

 the respiratory organs. Amphipods are usually, though not always, 

 laterally compressed. This puts them at a disadvantage for walking in 

 the open air. But isopods, being almost always dorso-ventrally depressed 

 or flattened downwards, have a more stedfast equilibrium, such as is well 

 exemplified in A. aquaticus. The brown colour marbled with white, 

 the long antenna? in front, and the slender two-branched uropods or 

 tail-feet prominently projecting from the consolidated pleon behind, 

 make this exceedingly common species easy to recognize. It is fully 

 and beautifully illustrated in an early work 1 by the distinguished 

 Norwegian carcinologist, Professor G. O. Sars, and more concisely in 

 his recent description of the Isopoda of Norway. 2 



Of the Isopoda terrestria, or woodlice proper, if so unscientific a 

 term can be called proper, Warwickshire might be thought to be wholly 

 destitute, to judge by the silence of its zoological records. It is however 

 quite certain that in this county as in others Oniscus ase//us, Porcellio 

 scatter, Philoscia muscorum, Armadillidium vu/gare and various other species 

 are to be found, in gardens and woods, in dry ditches by the roadside, 

 and almost anywhere under loose flat stones, amidst decaying leaves and 

 rubbish, or wherever their necessary food and shelter and a modicum of 

 moisture can be obtained. In the case of A . vu/gare and a few other 

 species that stable equilibrium with which nature has provided an isopod 

 can be sacrificed at will, the creature being able to ' conglobate ' its body 

 and roll out of reach of its enemies sometimes in a manner very un- 

 expected. 



Of the Entomostraca Mr. Bolton writes as follows : 9 '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, Macrotbrix roseus and Ilyocryptus sordidus? 



To make clear the relations one to another of these and several 

 other Warwickshire species it will be expedient to give in brief an 

 outline of the classification now generally adopted for the Entomostraca. 



1 Hittoire Naturelle des Cruttacet feau douce de Notvege, p. 93, ph. 8-10 (1867). 

 * Crustacea of Norway, ii. 97, pi. 39 (1899). 

 3 Handbook of Birmingham, p. 306. 



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