CRUSTACEANS 



counties.'^ To these may be added PMloscia muscorum (Scopoli), which 

 ' prefers dry rather than damp situations, under leaves, stones and moss,' 

 in accordance with the meaning of its name, the shade-loving tenant of 

 mosses, a species which ' is found abundantly throughout the southern 

 part of England,'^ 



The freshwater isopod, Asellus aquaticus (Linn.) and the freshwater 

 amphipod, Gammarus pulex (Linn.) occupy all counties without fear or 

 favour, the amphipod being like the isopod a sessile-eyed crustacean, 

 that is to say, not having the eyes articulated as is the case with those 

 organs in shrimps and lobsters. Otherwise an amphipod is very differ- 

 ently constructed from an isopod, having its heart in a different situation, 

 in connection with the circumstance that its breathing apparatus is not 

 in the tail part, but in the central compartment between head and tail. 



After so far constructing a hypothetical carcinology for Worcester- 

 shire, I had the satisfaction of having it to some extent confirmed 

 through a correspondence with the Rev. C. E. Ranken of Malvern, 

 president of the Worcester Naturalists' Field Club. Mr. Ranken con- 

 sulted the curator of the ' Hastings ' Museum, Victoria Institute, Wor- 

 cester, and that gentleman, Mr. William H. Edwards, took the trouble 

 of looking through several books and making enquiries. The conclusion 

 Mr. Edwards came to was similar to my own, for he says, ' No one seems 

 to have ever collected the Worcestershire Crustacea, hence we have no 

 authentic records.' At the same time he has begun to remove the defi- 

 ciency by transmitting to me the paper which I now have the pleasure 

 of quoting : — 



' Crayfish [Astacus fuviatilis) . We have a specimen in the museum 

 taken in the river Severn near Worcester Bridge a few years ago ; also 

 an old one from Dick Brook, Shrawley ; other localities for Worcester- 

 shire (as far as I know) are Crowle Brook and Dowles Brook near 

 Bewdley. 



' Freshwater Shrimp. I know nothing about the species or even 

 genera, but what is " locally " known as the " Freshwater Shrimp " is 

 common in the county ; but I am afraid this information is too vague to 

 be of any value, and I cannot put my hand on specimens now. 



' Woodlice. Armadillidium vulgare (the " Pill Woodlouse ") is 

 common throughout the county wherever I have observed. I have 

 seen large numbers when pupas digging. 



' Porcellio scaber (the " Common Woodlouse ") is only too common 

 everywhere. 



' Oniscus asellus. I am under the impression that I have seen this 

 in Worcestershire, but not being a collector of Crustacea, I have not 

 observed closely enough to determine it with certainty, and though I 

 have searched during the last few days, I have not been successful in 

 finding specimens.' 



On this welcome contribution a few remarks may be offered. 



The river crayfish belongs to the genus Potamobius, which in various 



1 Bate and Westwood, British Sessile-eyed Crustacea, vol. ii. p. 495. * Loc. cit. p. 451. 



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