220 Mr. F. E. Beddard on 
two pairs were visible, the outermost pair of each side 
being absent. The clitellum occupies four segments (14— 
17), but does not commence abruptly with the 14th seg- 
ment. On the hinder part of segment 13 there is already 
a slight development of glandular matter. 
Upon the 17th segment are the two male external gene- 
rative apertures, which are situated upon a flattened area 
marked off from the rest of the body by a continuous raised 
margin ; upon this area, and for a short distance in front of it, 
there is no development of glands; in front of the generative 
apertures, and corresponding to the lines of division between 
the segments, are three pairs of papilla, and in the segment 
immediately following the generative apertures there 1s 
another pair; behind these again is a single papilla corre- 
sponding to the right-hand one of the other segments ; and, 
finally, on the line of division between segments 12 and 13 
there is a single papilla on the left side, which differs from 
the others in being of a rather smaller size and in having a 
central perforation. ‘These papille were only present in a 
specimen which had a fully-developed clitellum. The papillee 
(fig. 4) are oval in form, with the long diameter transverse 
to the axis of the body; in the centre of each, with the excep- 
tion of the most anterior one, is an irregularly shaped de- 
pressed area. The position of the papille, situated as they 
are on the boundary-line of the segments, is unusual; in 
Megascolex affinis the two pairs of papille are situated in 
the middle of segments 17 and 19 respectively, and this 
position appears to be the same in other species of Mega- 
scolex which are provided with papille ; but in Pontodrilus * 
the two large papille are situated on the boundary-line of 
segments 19-20, 20-21. 
The enclosure of the generative orifices within an area di- 
stinct from the rest of the clitellum is not peculiar to the genus 
Typhous ; a similar condition has been described by Perriert 
in two other Intraclitellian genera, Anteus and Titanus, and 
more recently by myself ina new genus, Pleurochetaf. I may 
here remark that the pair of orifices on either side of the 
apertures of the prostate glands in this latter genus in all 
probability correspond to the genital papilla just described, 
which in other species are frequently perforated and conti- 
nuous with the ducts of small glands§. 
In the anterior region of the body, between the 7th and 
* Perrier, Arch. de Zool. Exp t.ix. 1881, pl. xiii. fig. 1, vv. 
+ Perrier, oc. cit. pp. 51, 58. 
{ F. E. Beddard, ‘Trans. Roy. Soc. Hdinb. vol. xxx. pt. 2, p. 481. 
§ Perrier, loc. ct. p. 107. 
