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Show 306 MR. F. F. LAIDLAW ON THE [Apr. 21, Family L e p to p l a n id ,e . L e ptop l an a m a l a y a n a , sp. n. (Plate XXIII. fig. 3 .) A number of specimens; some, preserved in formol, are of a uniform greyish-brown. Length, about........... 35 mm. Eyes, about............... 8 „ from the anterior end. Mouth-opening, about 15 „ ,, ,, <$ aperture, about ... 10 ,, from the hinder end. $ „ „ ... 1 „ from male. The arrangement of the eye-spots is that usual in the genus : there are two small clusters of " tentacle-eyes " about 1*5 mm. apart, and in front of these are a few scattered spots on either side of the middle line. This species is closely allied to L. pacificola von Plehn [7]. Genital Apparatus (see text-fig. 52). The vasa deferentia (v.d.) open into the proximal (anterior) end of the vesicula seminalis (v.s.); the latter, of considerable length and much twisted, is lined with ciliated epithelium, and has thick Text-fig. 52. Genital apparatus of Leptoplana malayana. a.f., antrum femininum ; acc.ves., accessory vesicle; sh.gl., shell-glands; u.t., uterine duct; v.d., vasa deferentia. For other letters see p. 318. muscular walls made up of circular fibres. At its distal end the vesicula narrows into the ductus ejaculatorius (d.e.), which is shorter, but, like the vesicula, much twisted. Its walls are like those of the vesicula, but it is much narrower and has a less well-developed muscle-layer. The penis is small, fleshy, and unarmed, and projects into the large antral chamber, which has thick muscular walls and extends vertically upwards almost to the level of the dorsal body-wall muscles. (See Plate XXIII. fig. 3.) The female opening lies close behind the male, and leads into a moderately large antral chamber (a.f.) with muscular walls. Into this the vagina opens from above. This latter organ is a long and tortuous duct of varying diameter ; the shell-glands (sh.gl.) open into it through nearly its whole length. At its hinder end, near |