In nearly all old lists in which records are found we meet the two entries, Lumbricus terrestris and Tubifex rivulorum. Under these two names were included respectively all the common species of Earthworm, and all the usual bloodworms of ponds, ditches, and streams. As the old Lumbricus group has been worked out, new genera and species have been differentiated, so that to-day it would be inadmissible to make an all-round entry under this heading; similarly with Tubifex. Much has been done of late years by a few English specialists, and more by continental workers, to extend our knowledge and analyse results. The term Tubifex is now used not only in a generic sense, but has been raised to the rank of a family, under which nearly twenty well-defined genera are grouped. The difficulty at present is to know to what genus or species the old records are to be assigned. Evidently the only way to settle the matter is by making an accurate entry every time any one or other of the Tubificidæ is found. Having examined a good many specimens from various parts of England and Ireland, I think it may be well to place on record here the localities and species about which no question can exist. I do not profess to give a complete list of all the species I have myself examined, nor do I include habitats recorded by Benham and others; but simply put down a few indisputable items as a nucleus around which further records may gather as research extends. I have undoubted records from the following places of—
1. Tubifex rivulorum, Lam.—Gasworks, Idle, near Bradford, and banks of Aire around Apperley, Yorks; dykes at Pevensey and ditches at Dallington, Sussex; banks of Derwent and muddy backwaters around Cockermouth, Cumberland; Ocker Hill, Tipton, Staffs.
