26 RECORDS OF THE AUSTRALIAN MUSEUM. 



Genitalia. — The genital pores alternate regularly 5 9 . Each is 

 situated in a shallow cloaca on a prominent papilla just in front 

 of the middle of the margin of each segment. When the cirrus 

 is everted the papilla projects very considerably as is shown in 

 PI. iv., tig. 4. A female pore is absent. 



The male organs are situated in the anterior portion of the 

 proglottis in front of the female genitalia. The testes are 

 numerous, there being about one hundred and fifty arranged in a 

 transversely-lying group of 1 - 85 mm. in breadth, in the anterior 

 third of the segment. They form a well defined mass which is 

 rather wider at the extremities than in its mid-region. There is 

 no grouping of the glands into two distinct series such as is figured 

 by Fuhrmann 00 as occurring in Acoleus vaginatus. There are two 

 or three rows in the dorso-ventral direction. The vesicles are 

 restricted to the dorsal portion of the medulla. Their diameter 

 is about O070 mm. Passing through the middle of the mass, is 

 a collecting tube into which the vas deferens from each gland 

 opens. From near the middle of the collecting vessel there 

 passes away the vas deferens which travels below and usually in 

 front of the testes. After a short course laterally it enters the 

 powerful cirrus sac without having been thrown into any coils. 

 Just within the cirrus sac the vas becomes much enlarged to 

 form a vesicula seminalis. From this the cirrus passes out 

 laterally as a tube with strongly muscular walls and a rather 

 narrow lumen. It lies more or less coiled when at rest, the 

 coils being restricted to the inner half of the cirrus sac. As 

 previously mentioned, the genital duct, or rather the cirrus sac, 

 lies ventrally to both excretory vessels and the main nerve, all 

 of these structures being displaced dorsally in this region. 



The cirrus sac is a very long and powerful cylindrical organ 

 occupying one of the upper corners of the segment. In its 

 position of rest it is 0-8 to 120 mm. long by about 0*26 mm. 

 broad. Its outer wall consists of a thick layer of muscular tissue 

 while the space between this and the male canal is traversed by 

 the fibres of the retractor muscle of the cirrus, which passes back 

 from the cirrus to be inserted into the sides of the inner portion 

 of the sac (PI. iv., fig. 4). Passing inwards from the external 

 wall of the latter, there is a very prominent retractor of the sac, 

 the fibres of this muscle coursing inwards from the sac to be 

 inserted into the ventral region of the medullary parenchyma. 



G9 In a few instances the cirrus sac was seen to open on the same side in 

 two successive segments. 



B0 Fuhrinaim — Loc. tit., p. 621. 



