1012 MR. R. J. ORTLEPP ON THE 



generally three pre-anal and five pairs post-anal. Spicules un- 

 equal, subequal, or equal. Yulva in anterior half of body. Two, 

 four, or many uteri. Eggs oval, smooth, thick-shelled, and 

 embryonated when laid. 



Parasitic normally in the digestive tract, generally the stomach, 

 of mammals, birds, and reptiles, but very rarely in amphibians. 



Type-species, Ph. clausa Rud., 1819. 



Group Didelphys. 



(1) Physaloptera clausa Rudolphi, 1819. (Text-figs. 2-4.) 



Syn. Spiroptera clausa (Rud.), Duj., 1845. 



The material examined consisted of many specimens from 

 Urinaceus europceus in the Yienna Museum (bottles 4447 & 4450), 

 also some specimens from the same host in the collection of 

 Prof. R. T. Leiper. The three lots of material were in all 

 respects identical. 



The cuticle appears smooth, but under high magnification a 

 very delicate transverse striation is s 3en ; it is only very slightly 

 reflected over the base of the lips. 



The cervical papillae are lodged in small depressions of the 

 cuticle, and are situated from 115 to 165/^ behind the level of 

 the hind end of the muscular oesophagus ; the excretory duct 

 opens in the ventral mid-line at the same level as the cervical 

 papillae or just behind them. 



The lips are almost semicircular in lateral view, but appear 

 square in dorsal or ventral view. Each bears a medium-sized 

 conical outer tooth with obtuse tip, and just internal to it a 

 median tooth of equal height with three tips to its free end. 

 No lateral teeth are present. The subdorsal and subventral 

 external papillae are small and dome-like. 



The oesophagus immediately follows the lips ; it is straight, 

 and forms in the female 1/7-8 to l/9th, and in the males 1/5-4 to 

 1/5-6 of the total body-length. Its muscular part is distinctly 

 set oif from the glandular, and is also slightly thinner; in the 

 females it forms about 1/8-5, and in the males l/7th of the whole 

 organ. The nerve ring encircles it in its posterior quarter. 



Female. 



Mature females vary in length from 30 to 50 mm., with a 

 maximum thickness of 1-3 to 1*6 mm. The body is attenuated 

 in its anterior l/3rd and posterior l/5th ; it is terminated by a 

 bluntly conical tail l/45th to l/55th of the total body-length, 

 with caudal pores in its posteiior lialf. 



The position of the vulva divides the body in the ratio of 

 1:1-7 to 1:2; it is situated on a slight elevation, and leads 

 into a bent vagina 1-6 mm. long by 95 yu broad ; the egg-chamber 

 is slightly shorter but thicker, measuring 1-3 mm. long by 325 fx 

 broad. From its posterior end the uteri, of which there are two, 



