NEW BRITISH OLIGOCHATS. 221 
nor Pachydrilus, is correct. While the worm is an undoubted 
Tubificid, it is the only species yet discovered in Britain which 
has set like Pachydrilus. In this respect, therefore, it is a link 
between the red-blooded Enchytreids and the Tubificids. Pachy- 
drilus lineatus, which is entirely distinct from Senuris lineata, 
will be dealt with later. My notesshow: Length about 20 mm.; 
segments 65; Twbifex-like in character, coiling up, and not 
swimming or crawling like Pachydrilus. Head and tail pale, 
body in the middle ruddy brown, owing to blood-vessels (red) 
and chloragogen cells (brown). Absolutely no capilliform sete, 
and no forked set, but all (2-4) of the Pachydrilus type. Hearts, 
as in Clitellio, in 8th and 9th segments. Nephridia in $ and 
7, with glandular cells, clear, as in Limnodrilus; also in seg- 
ment 12 and later. Chloragogen cells begin in 6; no strong 
pharynx as in Enchytreids, but cephalization exactly as in 
Tubificids. Pores on segment 11 without ventral sete. Brain 
convex in front, incised behind. No girdle, no clearly defined 
ova; and, as the specimens were not adult, certain important 
organs could not be studied. Possibly the testes occupy seg- 
ments 9-13. Some problematical glands were seen in segments 
4-5, such as are not found in any other known Tubificid or 
Enchytreid. 
2. InyopRILUS MEGANYMpPHUS, Friend.—My recent researches 
show that the Tubificids have to be revised. Authors have 
hitherto confused the issues by generalizing on too slender a 
knowledge. It is certain that the Tubificide of Great Britain 
are much more numerous than has generally been supposed. 
While Hisen, Stole, and others have written much about Ilyo- 
drilus, the differences between this genus and the true T'ubifex 
have not yet been clearly defined. For the present I take 
Tubifex to have three different kinds of sete, while Ilyodrilus 
has but two, viz. capilliform and forked. Pectinate sete, which 
are said to be present in T'ubifex, are wanting in Ilyodrilus. If 
ultimately it is found that the length of the duct is a truer 
genus-character, we shall have to put some species of Ilyodrilus 
under T'ubifex. 
The species now recorded was found for the first time in a 
little runnel which flows through the Alexandra Park at Hastings. 
The description will duly appear, with that of other new species, 
