| OCR Text |
Show 1903.] FROM ZANZIBAR AND BRITISH EAST AFRICA. 109 The genus may be defined very briefly as follows :-Lepto-planoid with flattened leaf-like body. A pair of long muscular vesicula? seminales, which lie parallel to the median ductus ejaculatorius and penis and receive the vasa deferentia of either-side respectively at their hinder ends. HAPLOPLANA ELIOTI, gen. et sp. nov. (Plate IX. fig. 4.) Two specimens dated 25.3.01. One of them is immature; the other, from which I prepared sections, is in a late stage of sexual activity, and the centre of the body is crowded with eggs. The body is oblong, about 6 m m . in length, 3 in breadth, with rounded ends. In places it is as much as 1 m m . in thickness. The eye-spots are arranged in two irregular lines lying over the brain on either side of the middle line. They are not numerous (text-fig. 6). Text-fig. 6. /* *\ -? o Haploplana elioti, sp. nov., magnified and (b) natural size. On the dorsal side the epithelium contains a number of pseudo-rhabdites. On the ventral surface close to the margin there are numerous small rhabdites on either side, but these do not occur elsewhere. The basement-membrane is thin, and the muscles of the body-wall are very feebly developed. On the dorsal side these consist of a narrow longitudinal layer followed by a few circular fibres. O n the ventral side there is an additional inner longitudinal layer. The dorso -ventral musculature is well-developed. The ovaries are dorsal, the testes ventral. The pharynx is of a very simple type ; it consists of a fold projecting from the middle of the wall of the oval pharyngeal pouch, the longer axis of the pouch coinciding with the main axis of the body. The opening into the gut lies rather in front of the opening to the exterior, which is about at the middle of the pouch (see PI. IX. fig. 4, ph.t.). The gut-branches are numerous and appear to undergo anas- |
