142 T. H. JOHNSTON. 



five to fourteen micra long by from five to seven micra broad. 

 In ripe segments, these bodies are abundant except at the 

 anterior ends around the retractor muscles of the cirrus. 



Genitalia :— The genital openings are all placed on the 

 right side. In matured segments, they appear as large 

 cup-shaped depressions with a crenate rim, situated on a 

 very bulky genital papilla which lies near the anterior 

 margin of the segment close to the posterior border of the 

 preceding segment. When the cirrus is everted, the papilla 

 is very prominent. 



The genital rudiments may be recognised fairly early as 

 a longitudinally placed mass of cells, somewhat spindle- 

 like, situated in the middle of the segments. Later, the 

 posterior part of this cord differentiates into the small 

 rounded testes and the female complex. The male glands 

 are now seen as a circlet of six vesicles surrounding the 

 developing female glands (Plate 8, fig. 4). Each testis is 

 about 10 by 8/x. The middle and anterior parts of the cord, 

 especially the latter, now become enlarged and develop 

 ultimately into the female and male ducts respectively. 

 The female glands now increase considerably in size. The 

 vagina, the vas deferens and especially the cirrus with its 

 sac become very prominent structures, the cirrus now 

 possessing its characteristic internal covering of bristles 

 arranged with their free ends pointing outwards. By this 

 time the ducts can be traced to the genital opening. 



The testes are very few in number, only seven or eight 

 being present. They lie rather more dorsally than the 

 female complex. Their arrangement is very characteristic, 

 six vesicles forming a ring around the immature female 

 glands. This recalls the arrangement described by Prof. 

 Fuhrmann 1 as occurring in his genus Cyclorchida. The 



1 Fuhrmann, Centrb., f. Bact. u. Par., Orig., I, xlv, 1908, p. 525 ; id., 

 Zool. Jahrb., Supp. Bd., x, i, 1908, p. 62. 



