98 



MR. R. GUKNEY ON LEANDER LONGIROSTRIS 



It may be of interest not only to give some account of the dis- 

 tribution and habits of L. longirostris in Norfolk, but also to add 

 some notes on the remaining four species of British Prawns. 



The structural specific differences have been dealt with so 

 thoroughly by De Man that it is not necessary to repeat them in 

 great detail, but I have added some account of the colour of 

 living specimens, since the species may readily be distinguished 

 when alive by colour alone, and this is a character to which 

 sufficient importance has not been attached. Some account is 

 also given of the range of variation of certain characters which 

 ai-e regarded as of specific importance. 



In the following table, measurements are given of typical 

 examples of the five British species. For purposes of comparison 

 the absolute measurements of the antennule and second leg have 

 been converted into percentages of the peduncle and dactylus 

 respectively. Thei'e is much individual variation, and the pro- 

 portions of these parts are very different in immature specimens, 

 so that such selected examples can only be taken as a general 

 guide; but they illustrate very well the characters of the differ- 

 ences generally to be observed. 



Table I. 



Measurements of typical individuals of the British species of 

 Prawn. The measurements for 2nd leg and antennule are 

 converted to percentages of the dactylus and peduncle 

 respectively. 



