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from the worm-like members of the family Anthuridae to the round- 

 bodied slender legged form — such as Munna — found among the 

 Asellota and to the strange misshapen parasites of the sub-order 

 Epicaridea, many of which show no signs whatever in the adult 

 form of their Crustacean affinities. It seems strange indeed to 

 see Crustaceans, belonging to such a highly developed order as the 

 Isopoda, without head, without legs, and without internal organs, 

 a mere sack of eggs almost incapable of movement, but there can 

 be no doubt of the relationship of these forms. A very large 

 number are parasitic in habits, including the whole of the 

 Epicaridea and a large number of the Cymothoidae, while the 

 Gnathiidae are also parasitic during the larval stage. 



The species of which I am going to speak are, for the most 

 part, inhabitants of the shore line, but at the same time a large 

 number of deeper water forms are to be found in various parts of 

 the English Channel, and can often be obtained from the fisher- 

 men, who in many cases are only too familiar with species of 

 Fish-lice belonging to the immense family Cymothoidae. My 

 records for the Bournemouth area do not, however, include any 

 species which is not to be taken in comparatively shallow water. 



There are in this district three well defined groups of hunting- 

 grounds for marine Isopods : — The brackish waters of Christ- 

 church Harbour and of the lake in Poole Park ; the rocky coast 

 from Totland round the Needles to Freshwater Bay and at Stud- 

 land and Swanage ; and the various local piers. In addition, two 

 species belonging to the genus Eurydice are to be found along 

 the sandy shores at Boscombe, Swanage, etc. 



Of course, the most easily available collecting grounds — and 

 therefore those which most appeal to myself and the other not- 

 too-energetic zoologists of the district — are the piers at Boscombe 

 and Bournemouth, but, as might be expected from the nature of the 

 sea-bottom, these are not nearly so productive as those at Swanage 

 and Totland. I have, however, taken one very interesting Isopod 

 on Boscombe Pier and one which, so far as I can discover, is 

 entirely new to the British Fauna. This is Clypeoniscas hariseni 

 (Giard and Bonnier), a species formerly recorded from Denmark 

 and from Greenland and described and figured by Prof. Sars in 

 Part II. of his " Crustacea of Norway " : it is parasit : c within the 

 brood-pouches of Idoteas, which, strangely enough, are also 

 Isopods, this being one of the rare cases of an animal parasite 

 on another member of the same order. The species on which I 

 have taken it is Idotea pelagica, the first record of the parasite 

 from this particular host. I may mention that this Idotea is one of 

 the commonest Isopods in this district and is very plentiful among 

 the mussels on Boscombe Pier. The female of Clypeoniscus is 

 about 4 millmetres long and is of a flattened and roughly oval 

 form : it is one of the most remarkable examples of degeneration 

 with which I am acquainted as it consists of a mere sack of eggs 

 without head and without appendages, its only functions being to 

 absorb the juices of its host and to develop the eggs which occupy 



