NEMATODE GENUS PHYSALOPTERA. 1055 



determine their Bumber by dissection, as it is almost impossible 

 to see them by simply clearing and rolling the worms. Secondly, 

 in the size of the females; his longest specimens were 55mm. 

 long, whereas mine reached 100 mm. And, thirdly, in the size 

 of the spicules ; the left spicule, according to my observations, 

 appears to be longer than in his. 



The only other Physaloptera from man is Ph. caucasica 

 V. Linst., 1902. The arrangement of its male bursal papillae is 

 very similar to tliat of Ph. mordens, except, as Leiper has pointed 

 out, that the 3rd pair of post-anal ventral papillfe is nearer to 

 the mid-line than in Ph. inordens. These two species, however, 

 appear to be distinct, as shown by the presence of only one tooth, 

 smaller spicules, and larger eggs, in conjunction with the much 

 smaller body in Ph. caucasica. 



The nature of the labial armatuie, mode of origin and number 

 of the uteri, general shape and size of the male bursa, distribu- 

 tion of the bursal papillae, and the great inequality in the length 

 of the spicules, allies this species to the reptilian species 

 Ph. abhreviata, Ph. varani, and Ph. antarctica. To the mam- 

 malian species Ph. numidica it is also related, as shown by the 

 number and shape of its teeth and the character of its female 

 genitalia. Ph. mordens is, however, easily distinguished from all 

 these by its much larger size, relatively longer tiamk portion in 

 the female genitalia, and by its much larger spicules. 



The occurrence of this sj^ecies in monkeys from Nyasaland is 

 very interesting, and leads one to think that these Primates are its 

 normal hosts, man being only an accidental one ; this view is 

 further sujDported by the fact that its onl}^ occurrence in man 

 is in the natives of East and Central Africa. 



A parallel case in West Africa is the occurrence in monkeys 

 and man of G^so2:>hagosto7num apiosiomum (Willach, 1891), Raill. 

 & Henrv, 1905. 



(20) Physaloptera tumefaciens Henry & Blanc, 1912. 

 (Text-figs. 29 & 30.) 



The material examined consisted of three males and three 

 females, kindly placed at my disposal by Prof. Leiper. This 

 material was part of the collection of worms from which Heniy 

 and Blanc described the species, and was presented to Prof. Leiper 

 prior to the publication of their description. In addition, two 

 males, obtained from a Macactcs fascicularis which had died in 

 the Gardens of the Zoological Society of London, were also 

 studied. 



The cuticle is A^ery finely striated transversely, and also shows 

 a coarse cuticular ringing. Anteriorly it is reflected over the 

 lips, and this may also be the case over the tail region in both 

 sexes.; this posterior reduplication of the cuticle may pass over 

 as much as the anteilor third of the bursa in the male ; in the 

 females it only forms a narrow collar in front of the anus. The 



