A HISTORY OF BUCKINGHAMSHIRE 



described as ' semi-pellucid, of a clear golden yellow colour, with a 

 diffuse minium-red pigment on the back, forming slight ramifications 

 on each side of the segments.' The head has an evenly-rounded front, 

 and is roughened with little tubercles, of which there are transverse rows 

 also on the segments of the perason or middle body. The earlier 

 segments of this part have the postero-lateral corners rounded, the sixth 

 and seventh are angularly produced backwards. The second antennas 

 have the flagellum four-jointed. In the last pair of legs there is a dense 

 ciliation on the outer margin of the sixth joint, and in this the finger to 

 some extent participates. The single specimen procured appears to be 

 a female, as it is without the dentiform projection at the base of the 

 fourth joint, described as characteristic in the seventh pair of legs of the 

 male. From the same locality was derived a solitary specimen of 

 Haplophtbalmus mengii (Zaddach), not previously recorded in this country. 

 The generic name intimates that the eyes are simple, a character shared 

 as we have seen with the preceding species, with which it agrees also in 

 the ciliated margins of the seventh pair of feet and various other details. 

 But it has also characters by which it is easily distinguished. It is paler 

 and smaller, being white in colour and barely an eighth of an inch in 

 length. The head has a triangular front, and dorsally from about the 

 middle it is traversed by longitudinal ribs, which are repeated in six lines 

 on the segments of the person. On the third segment of the pleon are 

 a submedian pair of ribs, which are very distinctive, as nothing of the 

 kind is found on H. danicus or allied species in neighbouring genera. 

 The beauty of this little crustacean is attested by the name H. e/egans, 

 given to it by Schobl, who wrongly supposed it to be a new species when 

 instituting for it the genus Haplophtbalmus in 1860. 



Of the family Oniscidas there are several species in this district. 

 For convenience of recognition they may be divided into two sets, those 

 that have the flagellum of the second antennas three-jointed, and those in 

 which it is two-jointed. To the former belongs Philoscia muscorum 

 (Scopoli), a lively, shining, often brightly coloured species, considerably 

 larger than the members which have been discussed of the preceding 

 family. It resembles them in regard to the contracted pleon and the 

 well displayed uropods, but its eyes are more strongly developed, its 

 antennae are not spiny, and the apex of its body is acute. Miss Johnson 

 has sent it from Lane End, and Mr. Webb reports it from several places, 

 to which no doubt innumerable additions could be made by simply 

 extending the search. Similarly Oniscus asellus, Linn., is reported from 

 Iver, Langley, Eton, Eton Wick, Hedsor, Burnham Beeches and Fulmer. 

 This large and broad, rather smooth, slow-moving crustacean is tolerably 

 well known. The contour of the peraeon and pleon here present the 

 continuous lateral curves of an oval, in contrast to the interrupted lines 

 of all the preceding species. Moreover, the inner branch of the uropods 

 in this and most of the species to be subsequently mentioned is almost 

 hidden beneath the apical part of the body, the outer branch alone pro- 

 jecting conspicuously. From Hedsor Mr. Webb has submitted to me 



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