SOME ANNELIDS OF THE THAMES VALLEY. 95 



Some Annelids of the Thames Valley. 

 By the Rev. Hilderic Friend, F.L.S., F.R.M.S. 



(With Text-figures.) 

 [Read 21st December, 1911.] 



I AM anxious at the outset to guard against the idea that the Thames Valley, 

 any more than other parts o£ England, has been exhaustively worked. We 

 are familiar with a goodly nnmber of worms, particularly those belonging to 

 the two families known as the Lumbricidse and the Tubificidje. We know 

 something also of the Naididse, but of the large and important family of the 

 Enchytra?idse we are still in almost absolute ignorance, in spite of the fact 

 that some 30 species of the genus Frklericia alone are already recorded as 

 British. 



I have chosen the Valley of the Thames, rather than the river itself, as my 

 fields because I am thereby enabled to draw attention to the excellent work 

 done by those able pioneers who have prepared the way for my own more 

 recent researches. The greasy, foetid ooze of our great river does not present 

 a very attractive hunting-ground for the naturalist : yet the treasures it 

 contains will amply reward the worker who has the courage to ignore its evil 

 odours, or to risk the covering of his boots with a most disagreeable slime. 



Although the Thames Valley has as yet been but partially worked^ there 

 is perhaps no section of the country which has received so much attention 

 in relation to the Oligochpets. It is a pleasure, therefore, in the first place 

 to give 



A BRIEF HISTORICAL SURVEY. 



I do not pretend to have looked up every detail, but have endeavoured to 

 do justice to all who have done anything to further our knowledge of the 

 subject since the dajs when the study of terrestrial and freshwater annelids 

 became a scientific pursuit. The honour of being first in the field in this 

 connexion undoubtedly belongs to Sir E. Ray Lankester. Not less than forty 

 years ago (1) he recorded the discovery of Psammoryctes ?>a?'^a^«5, Vejdovsky, 

 in brackish water at Barking. The worm still exists in the same locality, 

 and will be considered again at a later point. In June 1898 Dr. Benham 

 wrote (2) that, so far as he was aware, the species had not been recorded again 

 till he found it in the mud amongst the roots of reeds in the Gherwell. 



In the eighties at least three workers were adding to our knowledge of the 

 subject. Oerley (3), a most careful and advanced Hungarian student, was 

 working in England at this time, and among other discoveries found 

 Octolasium platijurum^ Fitz., at Cambridge, and 0. riilddum, Oerley, at 

 W^oolwich. These records have not since been confirmed, but Oerley has so 



