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Show 1000 MR. F. E. BEDDARD ON A [Dec. 18, segment. 1 have not counted those upon the body generally, as I have been unwilling to injure m y only specimen. There are 13 seta? lying between the male pores. At the posterior end of the body the seta? are again rather larger and further apart from each other. This increase in size of the seta? at the end of the body is very strongly marked in such a genus as Onychochceta, but I have not observed it to occur commonly in Amyntas \ There are dorsal pores, but I a m unable to state the exact segment at which they commence. They are at any rate visible upon the clitellum. The clitellum extends over segments xiv.-xvi. and includes the whole of those segments. It has no setae upon it. The male pores are very inconspicuous. They lie as usual in tbe line of seta?. There are no differentiated genital papilla? anywhere upon the body ; but, as is shown in the accompanying drawing (fig. 1, p. 999), there are depressions of a groove-like character which may perform the function of adhesive papilla?. One of these lies in front of each male pore ; the other, the longer, lies behind it. They are encircled by rather tumid walls. There is in addition a slight medianly placed furrow in front of and behind the line of seta?. The oviducal pore is single and median and upon segment xiv. The spermathecal pores were not visible externally, but tbe point of their opening would seem to correspond to that of the male pores. The alimentary canal calls for no special description except to mention that the intestinal ca?ca are rather long; when fully extended they reach as far forward as the posterior margin of the spermiducal gland, i. e. to the xxth segment. They arise as usual in the xxviith segment and taper gradually towards the tip; there is no trace of secondary ca?ca. The ca?ca are very much longer than those of A. trinitatis. In front of the gizzard there are three very stout intersegmental septa. They are bound together and to the parietes by numerous thin strands of muscle. The septum separating segments viii. and ix. is entirely absent. The gizzard is bound to the septum which follows it by a pair of very stout ventrally placed muscular bands. The first two septa after the gizzard are fairly thick and the size diminishes in the next two or three, all of which, however, are tied to each other and to the parietes by thin muscular strands. The last pair of hearts lie in segment xiii. The reproductive organs show certain features which are of use in the discrimination of the present species from A. trinitatis2 or A. heterochcetus 3, which are its nearest allies, especially the former species. The sperm-sacs in xi. and xii. are not in any way remarkable. The spermiducal glands (fig. 3) are large, extensively lobulated. 1 It is to be found, however, in A. heterochcetus. 2 Beddard, P. Z. S. 1896, p. 206. ;i Horst, Nederl. Arch. f. Zool. iv. |