Page:Transactions of the Royal Society of Tropical Medicine and Hygiene, volume 1.djvu/104

80 one-eleventh of the body length, in the male, from the tip of the tail.

The bursa in the male is oval in outline, tapering posteriorly. The papillae are in number and in general disposition according to the type of the genus, but in minuter detail of the relation of the individual papillae to one another the following points are to be noted. The external series of four pairs of pedunculated papillae do not lie in one straight longitudinal series, but are disposed so that the first and fourth pairs lie considerably within the middle, i.e. second and third, pairs (Fig. 4).

Of the sessile series of papillae the only point to note is that, in contrast with the arrangement described and figured for P. caucasica, the most anterior of the three hindermost pairs of sessile papillae on the tail are much more widely separate from one another than are the members of the two succeeding pairs.

As in P. caucasica and many other species, the ventral surface of the bursa has a peculiar "rough-shod" marking of the cuticle that lies between the most anterior pair of papillae and the second pair from the posterior end, the cuticular markings extending between this second last pair and gradually disappearing, doing so more quickly from the sides than in the centre line.

The male genital system consists of three distinctly-defined portions of the long single genital tube and a pair of very unequal spicules. The genital tube lies almost entirely on the ventral aspect of the body cavity, keeping the alimentary canal, in its whole length, on its dorsal aspect. The ejaculatory duct, the most terminal part, measures about one-fourteenth of the body length and shows well-developed musculature in its walls. The portion immediately succeeding, viz., the vesicula seminalis, is a wide and lengthened tube having a peculiarly reticulated wall, and extending forwards without kink or coil for a distance