Parasitic Worms from East Africa. 291 



adanalj and about ten preanal, in a regular series. Imme- 

 diately in front of the cloaca there is an unpaired ventral 

 papilla. Two very unequal spicules (fig. 6, l.sp., r.sp.) and 

 an accessory piece (fig-. 6, a.p.) are present. The left spicule 

 measures 2*7 mm. in length, and is very slender. The right 

 spicule is much stouter, but measures only 0'5 mm. in length. 

 The latter is alate for the distal half. 



In the female the tail (fig. 7) is 0*35 mm. long and is 

 quite straight. On the ventral surface, close to the tip, it 

 bears a pair of minute papilla?. The vulva is situated in the 

 oesophageal region, just behind the neck-papilla?. The vagina 

 runs posteriorly as a narrow tube for some distance. The 

 two uteri run posteriorly in parallel coils. They are wide and 

 thin-walled tubes, containing large numbers of fully-formed 

 embryos, closely coiled together, and apparently not enclosed 

 in egg-shells. The species is therefore apparently viviparous. 

 The coils of the ovaries extend back to within 3'5 mm. of 

 the anus. 



Cestod A. 

 4. OocJwristica zonuri, Baylis, 1919. 



Host : Zonurus tropidosternum. 



Locality. Dodoma. 



The original specimens of this form* came from the same 

 host-species, from Portuguese East Africa. The present 

 specimens do not differ sufficiently from the type to be 

 regarded as a distinct species, but there are certain discrep- 

 ancies which indicate that the species 0. zonuri is a some- 

 what variable one. In size the present material is distinctly 

 smaller than the type, the longest complete specimen not 

 exceeding 80 mm. in length, while the greatest width is about 

 2 mm. The worms are less contracted in an antero-posterior 

 direction, and show a considerable unsegmented neck behind 

 the scolex. The scolex itself is slightly larger (about l'l mm. 

 in diameter). The suckers also are a little larger (0'55 X 

 0'4 mm.). The most posterior segments are lunger than 

 broad. The number of testes appears to be from eighty to 

 ninety, instead of sixty to seventy, as in the type. 



The measurements given in the key to certain species 

 of Oochoristica from lizards, in my former paper, should, of 

 course, be regarded as a rough guide only, and were intended 

 as such. It is clear that such measurements must be of rela- 

 tively small value in the case of cestocles, which are liable to 

 exhibit great variations due to different states of contraction. 

 * ' Parasitology,' xi. (1919) p. 406. 



