OCR Text |
Show 1886.] LITTLE-KNOWN EARTHWORMS. 305 diminish in size towards either extreme. Tbese glands are situated on the dorsal wall of the intestine, close to and on either side of the dorsal vessel; each is supplied with a rich plexus of blood-vessels derived from the most anterior of the two vessels which arise from the dorsal trunk in each segment. These glands are probably of the same nature as those described by myself in a similar position in Megascolexv and Typhosus*, and by Dr. Horst3 in Acanthodrilus. The female reproductive organs I have already described; they are quite unique in that the ovary is directly continuous with its efferent duct, which opens on to the exterior in common with the Generative organs of Eudrilus, with bursa copulatrix laid open. p, penial process; c, pad-like process connected with glandular appendix. Other lettering as in fig. 1. spermatheca. The male reproductive organs are also remarkable; they have been described by M . Perrier in all the three species of the genus ; m y own dissections do not altogether bear out his statements, but of course the differences may be specific ; they are hardly individual, inasmuch as three or four specimens agreed perfectly. In most cases there were three pairs of vesiculae seminales, situated in segments 10, 11, 12 ; with these are connected a pair of vasa 1 Trans. Roy. Soc. Edinb. vol. xxx. pt. ii. p. 493. 2 Ann. &. Mag. Nat. Hist, 1883, xii. p. 222. 3 Notes from Leyden Museum, vol. vi. p. 103. |