CRUSTACEANS 



added that Bognor is more dependent on its prawn fishery than on either 

 lobsters or crabs, and that the Httle lobsters are taken with the prawns 

 in the prawn pots.'' Mr. Guermonprez in 1902 reports the lobster at 

 Bognor as still abundant. Whether in this same tribe the family Potamo- 

 biidffi is represented in Sussex by the widely distributed Potamobius pallipes, 

 the river crayfish, I have not been able to ascertain. It is at least highly 

 probable that the species will be found in some of the streams. 



Of prawns the incidental mention has already been frequent, and 

 one could wish that the subject were as simple as the name is familiar. 

 But the words prawn and shrimp, being unscientific terms, have often 

 been applied interchangeably and without method, those who use them 

 being guided by differences of size and colour rather than by the 

 structural features and relationships of the animals. Most of them fall 

 to some one of the many families of the tribe Caridea. In the family 

 Palamonidas is included our best known English prawn, Leander serratus 

 (Pennant), of which Bell says, 'I found that at Bognor the fishermen 

 consider them, when young, as a distinct species, and assert that, at 

 certain seasons, they drive the true prawns from their ordinary place of 

 resort. The probability is that at the season when the young ones have 

 arrived at a certain age, they separate themselves from the older ones, 

 which at that period of the year retire further from the shore.' ^ There 

 are indeed few households of living creatures in which nature does not 

 exercise a centrifugal force of one kind or another, so as to check un- 

 wholesome concentration. Leander squilla (Linn.), a species very similar 

 to L. serratus, but smaller, is recorded by White from ' Sussex (Little 

 Hampton).'^ In the market place this species shares with some others 

 the colloquial names of white shrimps and cup shrimps. Palcemonetes 

 varians (Leach), which I have myself taken at Lancing, and which is 

 recorded by the Natural History of Hastings as common,* has the 

 peculiarity of making itself at home in fresh and brackish waters, whereas 

 the other two species are strictly marine. In all three it is only the 

 first two pairs of legs that are furnished with pincers, and it is the second 

 pair that is the longer, a different arrangement from that in the lobster, 

 which has an enormous first pair of chelipeds, followed by two pairs 

 that are minutely chelate. In the family Processidse the second pair 

 of legs, though longer than the first, are not so strong, and are tipped 

 with tiny nippers. Processa canaliculata. Leach, has a front pair of legs 

 that are not properly a pair, since only one of them is chelate, the other 

 being simple, that is devoid of a chela. Adam White records this species 

 in the British Museum collection from ' Bognor. Presented by Prof 

 Bell.' * We may assume that this is a boiled example, since Bell, speak- 

 ing of specimens, says, ' That from which my figure and the above 

 description are given was accidentally found by myself in a dish of boiled 

 prawns, on which I was about to breakfast, at Bognor, in the year 



1 Report on the Crab and Lobster Fisheries of England and Wales, p. xii. 



2 British Stalk-eyed Crustacea, p. 303. ^ List of British Animals in British Museum, p. 42. 

 ^ p. 4.0. s List of British Animals, p. 39. 



I 257 33 



