THE DECAPODA NATANTIA OF THE COASTS OF 



IKELAND, 



BY 



Stanley Kemp, B.A. 

 Plates I-XXIII. 



Inteodqction. 



The material which forms the basis of this paper was almost 

 entirely accumulated during the course of the fishery research 

 work carried out by the s.s. Helga since the year 1901. Owing 

 to the limited opportunities for work of this nature, it has only 

 been possible to investigate some of the more important areas 

 with any degree of thoroughness ; it thus happens that from 

 the north coast of Ireland records are available from a single 

 district oaly, Kathlin Deep, while several species have 

 doubtless escaped detection on the rich southern grounds. 

 The extensive and systematic trawling operations carried out 

 off the east coast, more particularly on the grounds between 

 Dublin and the Isle of Man, have probably yielded a fairly 

 complete census of the forms occurring in the Irish Sea, and 

 considerable attention has been paid to the deep-water dis- 

 tricts to the south-wTst of Ireland off the coasts of Co. Kerry 

 and Co. Cork. As might be expected, it is in this latter area, 

 in soundings of from 200 to 1,000 fathoms, that the majority 

 of the more interesting species have been obtained. These 

 south-western investigations have been well supplemented by 

 other deep-water work further north, both inside and outside 

 the Porcupine Bank, and off the coasts of Co. Mayo, but the 

 more inshore grounds inside the 100 fathom line still require 

 further examination. 



In addition to the material obtained by the Helga, a small 

 collection made by the Danish fishery steamer Thor has been 

 examined. These specimens, which were kindly communi- 

 cated to us by Dr. J. Schmidt, were all taken in the Atlantic 

 trough over an area ranging from the Faroe Is. to the Bay 

 of Biscay. 



Canon Norman, to whom I am indebted for the loan of 

 numerous specimens and for the opportunity of consulting 

 literature which was not available in Dublin, has very kindly 

 allowed me to use several hitherto unpublished records, and 

 I have also to thank Dr. Caiman, who has spared neither time 

 nor trouble in answering my numerous queries, for the readi- 

 ness with which he has placed his extensive knowledge of this 

 group at my disposal. 



Fisheries, Ireland, Sci. Invest., 1908, I. [1910] 



