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IX. — British Enchytraeicls. 

 By The Eev. Hilderic Fkiend, F.R.M.S. 



[Read March 19, 1913.) 

 Y. Species New to Science. 



Aided by a Government grant, it has been possible for me during 

 the past year to add greatly to our knowledge of this large and 

 interesting group of microscopic Annelids. It is my purpose, in 

 the present contribution, to describe a few of the species which 

 have been discovered by me in different parts of the country. 

 They are all new to Britain, and as far as I have been able to 

 ascertain, new to science as well. While the bulk of the species 

 belong to genera which have been for some time recognized by our 

 leading systematists, it is pleasing to be able to record the 

 discovery of an indigenous Enchytr?eid which differs in many 

 important particulars from all the previously known generic types, 

 and this must be for the present regarded as establishing a new 

 genus, which makes a revision of the entire family -characters 

 necessary. The new worm is a true Enchytraeid, as we understand 

 that term ; but, in order the better to appreciate its place in the 

 family, some preliminary observations on the group in general 

 will be of service. 



I. — Enchytr.^^.id Characters. 



Beddard (7)* gave us in 1895 some valuable information on 

 the family, summarizing the studies of such well-known authorities 

 as Claparede, Ude, Yejdovsky, Eisen, and Michaelsen, and in 

 particular adopting the conclusions of the latter writer. In general, 

 we may say that " all the Enchytraeidse have a prostomium ; in 

 most there is a single pore upon the prostomium," or between the 

 prostomium and the first segment, represented fractionally by 

 recent writers as 0/1, while in a few forms, chiefly belonging to 

 the genus Frideruia, there are dorsal pores as well. Though setae 

 are entirely wanting in the genus Afiachseta, there are 4 bundles 

 in each segment in all the other British genera as yet discovered. 

 These are never cleft or forked at the extremity, but are liable to 

 considerable variation in shape, size, number, and arrangement. 



The nephridia in this family have a characteristic form. They 



* The figures within brackets refer to the Bibliography at the end of the paper. 



