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roll into the smallest crevices from which it is almost impossible 

 to extricate them on account of the smooth slippery surface which 

 they present to the collector. Much trouble in the identification 

 of species in this family has been caused by the extraordinary 

 differences which exist between male and female, and young and 

 adult, in the same species as well as by the large number of 

 variations found, but, fortunately, we have, in Dr. Hansen's paper 

 on their family, a sure guide through the bewildering maze of 

 sexual, larval, local and other forms. The Gribble, Limnoria 

 lignorum, which I have mentioned before, belongs to this family, 

 and is undoubtedly the most interesting of the local Sphaeromidae. 

 It is particularly plentiful in the woodwork of Totland Pier, where, 

 together with the notorious Amphipod Chelura terebrans, it does 

 an incredible amount of damage to the piles : in its company in 

 the holes in the woodwork are found two other Isopods, Tanais 

 tomentosus and Leptochelia Savignyi, but it is improbable that 

 these are active agents in the destruction of the timber. The 

 Gribble is a small whitish Crustacean about 5 millimetres in length 

 and a little over 1 in breadth: like most of the members of its 

 family it is capable of rolling itself into a ball and its body and 

 appendages are strongly and compactly formed to aid it in its 

 boring habits. It is strange to think of the amount of damage 

 caused by such a seemingly insignificant creature and to watch it 

 at work on the woodwork of a pier one is half inclined to let one's 

 imagination run riot and to believe that the Gribble realizes the 

 result of its labours and enjoys the thought of the destruction 

 which it is causing. Various methods of warding off the attacks 

 of Limnoria have been tried, such as treating the piles with pitch 

 and similar preparations, but none have proved of any great 

 success, for the Gribble is more powerful than we are and still 

 costs this country some hundreds of pounds each year in repairs to 

 woodwork exposed to its attacks. 



I have prepared a list of the local marine and fresh-water 

 Isopods which I am asking the Secretary to publish in the next 

 report of our Society, but this must be for the present an essentially 

 preliminary affair. I am greatly indebted to Mr. H. J. 

 Waddington, F.L.S., for his permission to quote his records, which 

 have been of the utmost value to me in my preparation of this list, 

 but, at the same time, I am confident that if I had the time and 

 opportunity to make a thorough examination of the collecting 

 grounds in this district I could very largely increase my present 

 number of records, more especially as regards the parasitic 

 Isopods belonging to the sub-order Epicaridea. I am convinced 

 that this district is very rich in marine Isopoda, but it would 

 require several years' work to make anything like a complete list 

 of the species occurring in the neighbourhood. 



I do not think that the Isopoda are a group which lend them- 

 selves so much to faunistic studies as to general classificatory and 

 anatomical work, but at the same time Prof. Sars' volume on the 

 Isopoda of Norway shows what may be done with this subject 



