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Show 350 MR. F. E. BEDDARD ON [May 3, segments viii. and ix. are wider than the others; the pair of segment vii. are hardly of less calibre; the other contractile lateral vessels are decidedly thinner. The non-contractile perivisceral vessels were obvious in the posterior segments of the body. The first pair of "hearts " each give off a slender branch, which runs forward in the direction of the pharynx. I did not find a corresponding branch to arise from the following " hearts." The " stomach " is in segments x. and xi.; the wider part of the intestine commences in segment xiv., but there was some variability in this point. In some individuals I could recognize no narrow oesophagus following the "stomach." The lattice-work of bloodvessels upon the alimentary tract was in many specimens very clear. O n the " stomach " thisvwas particularly so, and I found a longitudinal trunk, such as Stole has figured in Nais, on one side; the nephridia vary much as to the segment where they begin. Perrier mentions the sixth segment, so too does Bousfield. In the first individual which I examined they were apparent from the viiith segment; in another they did not begin until the xiith segment; in a third the ninth segment contained the first pair. ii. Note upon Pristina longiseta. In a valuable paper upon the Naidomorpha, published in a recent number of ' The Quarterly Journal of Microscopical Science,' Prof. A. G. Bourne l remarks of Pristina longiseta, " This species has been recently re-described by Vejdovsky. I have not seen it, nor has it, so far as I know, ever been recorded from England." Having lately had the opportunity of examining a specimen, I offer the following remarks upon it. Firstly, its occurrence in England is of interest. There is no doubt, however, that the small number of aquatic Oligochaeta hitherto recorded from Great Britain is simply due to the fact that they have not been looked for. The worm has been figured by Leidy2, d'Udekem 3, and Vejdovsky*. Neither d'Udekem nor Tauber5 appear to have known of Leidy's paper. Vejdovsky does not refer to it in the list of synonyms of Pristina longiseta, but does mention both the paper and the species, without comment, under the description of the family Naidomorpha; in the table of known species of Naids and their distribution Vejdovsky does not cite N . America as a locality for Pristina longiseta. The double omission therefore leads me to the opinion that Vejdovsky was not certain as to the identity of the species termed by himself and Leidy Pristina longiseta. Vaillant, moreover, considers that the identity of the two is not fully established ; the only difference, however, to which he calls attention is a difference of 1 " On the Naidiform Oligochaeta, &c," Q. J. M. S. vol. xxxii. p. 352. 2 " Descriptions of some American Annelida Abrancbia," J. Ac. Nat. Sci. Philad. vol. ii. p. 44. 3 " Nouvelle Classification des Annelides Setigeres Abranches," Bull. Ac. Roy. Belg. t. xxii. p. 552. 4 System und Morphologie der Oligochaeten : Prag, 1884, p. 31. 5 Annulata Danica, 1879, p. 73, |