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 A HISTORY OF WORCESTERSHIRE particulars differs from Astacus, the genus of the lobster. Apparently also the specific name jiuviatUis is not the proper one for the crayfish of our English rivers, which ought rather perhaps to be called Potamobius pallipes. But whatever its exact designation, it has a special interest for inland counties as being the highest in rank of any Crustacea that they can produce. It is not the only stalk-eyed crustacean to be found in England in fresh water, but none of the others appear to be met with far inland, and none of them approach the crayfish in size. It is only now that its distribution in our island is becoming gradually better known. For its eastward extension Mr. Walter Garstang, writing to me from the Plymouth Laboratory under date December 13th, 1900, quotes Mr. H. D. Geldart as vouching positively for its occurrence in the headwaters of the Bure, and in some other streams of the county of Norfolk, and now Mr. Edwards adds Worcestershire in the west to its domain. Huxley, discussing the absence or apparent absence of these crustaceans from localities in which they might have been expected, says : ' It is still more remarkable that, according to the best information I can obtain, they are absent in the Severn, though they are plentiful in the Thames and Severn canal.' ^ The freshwater shrimp of which Mr. Edwards makes mention can- not well be anything but Gammarus pulex. The only other amphipods which the county is Hkely to possess are the subterranean species known as ' well-shrimps.' For their occurrence, indeed, we may claim one actual record, though whether it can strictly be called a specific record is open to question. In their interesting historical account of the genus Niphargus, Schiodte, Bate and Westwood include Worcestershire in the list of EngUsh localities from which specimens had been obtained. The specimens of which they are speaking are referred to the species Niph- argus aquilex, Schiodte. The authors explain that they are found in wells surrounded by very diverse geological conditions, and append the following footnote : ' Shortly after the exhibition of the specimens from Maidenhead, at the Linnsan [Linnean] Society, Mr. Edwin Lees informed us of the discovery by himself of a specimen in water from the well of his own residence in Cedar Terrace, Henwick, Worcester. This well had been deepened in the preceding year into the red marl, which is the formation under gravel. The animal had not been previously seen, and only a single individual was observed.' * Since Bate and Westwood record three species of Niphargus and one of Crangonyx from English wells, since these small, pale, blind or purblind species are not so very easy even for experts to distinguish, and since the authors do not claim themselves to have seen the specimen from Cedar Terrace, it would be rash to guarantee its belonging to Niphargus aquilex. But the prolonga- tion of the third uropods, which are the hindmost tail appendages, is a distinction between Niphargus and Crangonyx tolerably easy to observe, so that we may with some confidence accept the generic determination ' British Sessile-eyed Crustacea, vol. i. p. 313. 128
 * Huxley, The Cra^sh, International Scientific Series, vol. xxviii. p. 288, ed. 3 (1881).