(54 NOTES ON SOME ENTOZOA. 



a few rather wider convolutions. The greater part of the 

 sac is occupied by the wide eversible unarmed cirrus which 

 is capable of being everted to a length of -,20 mm., its width 

 in such a state being about 033 mm. The cirrus sac, 

 when the cirrus is at rest, is a pyriform organ -14 mm. 

 long and about -055 mm. /wide in its inner portion. .The 

 male pore lies postero-dorsally to the female aperture, 

 both terminating in a very short genital cloaca. 



The large bilobed ovary consists of numerous tubes 

 whose terminations lie dorsally, the ovarian bridge being 

 ventral. Its duct is short. Situated dorso-laterally in 

 the cortex in the region of the longitudinal nerve are the 

 vitelline follicles, each with a diameter of about -013 mm. 



The vagina is a wide tube lying antero-ventrally to 

 the cirrus sac, narrowing somewhat as it passes inwards 

 below -it and the vas deferens to bend backwards and travel 

 above the uterus. Just in front of and above the ovary, 

 there is a slight enlargement, the receptaculum seminis, 

 followed by a narrowed portion or fertilising duct into 

 which the oviduct enters. The shell gland lies in this 

 region. The uterus arises as a thin duct which passes 

 forwards ventrally, along the mid- line, below the OVary 

 and the vagina. Numerous short lateral diverticula 

 appear at an early stage, and as egg-formation proceeds, 

 these become much more prominent, until at length the 

 uterus appears as a much-branched structure almost filling 

 the medulla. The eggs measure from 15 to 19 micra in 

 diameter, and the oncospheres from 7-5 to 11 micra. 

 Vitellaria persist even in segments with fully formed embryos. 



Ophiotcenia Tiyloe appears to be the first adult cestode 

 described from an Australian amphibian. 



La Rue (1911, p. 473), has recently subdivided the 

 genus Proteocephalus, one of the genera being Ophiotcenia, 

 to which our form belongs. The differences between 

 Acanthotcenia and Ophiotcenia are very slight. The latter 

 might even be regarded as a subgenus of the former. 



AcanthotcBnia gallardi, Johnston. 

 (PI. II ; Figs. 3, 4). 

 This cestode was described by me last year (lOllo, 

 p. 175), under the name Proteocephalus gallardi, mention 

 being made (p. 181) that it belonged to the subgenus 



