AN ACCOUNT OF SOME HELMINTHES COLLECTED IN THE SUDAN 
193 
Family, A sc arid a; 
Genus, Ileterakis 
Iletcrakis numidcB, n. sp. 
Guinea fowl. Numida ptilorhyncha. Intestine. White Nile. 
This parasite appears to infest the guinea fowl of tropical Africa in a marked degree. 
Large numbers were collected from several birds by Dr. Wenyon in the Sudan, and I have 
obtained it also on various occasions during a recent collecting tour in Uganda. The 
arrangement of the genital papillte is peculiar, but in its mouth parts it appears to resemble 
somewhat closely a larger species, H. compressa, described by Schneider and obtained from a 
domestic fowl of Australia. 
The parasites are of a whitish colour, are stoutly built and fairly thick, measuring in 
length 17’5 mm. in the male, 25 mm. in the female. The sexes are not easily distinguishable 
liy the naked eye, but the males arc more truncate at the posterior extremity than are 
the females. 
The mouth is guarded by three large distinct lips such as are found always in Ileterakis and 
Ascaris. There are no intermediary lips. Just after its origin each lip is slightly constricted 
laterally, and then expands into a wider distal portion that is in general shape triangular, with 
each angle distinctly rounded off as a well-marked protruding lobe (see Fig. 44, A). The fleshy 
pulp contained within each lip is shaped pretty much after the same fashion. It is indistinctly 
lobed but is undivided, thus resembling closely the condition described by Schneider for 
H. compressa, in contradistinction to that occurring in other Heterakis. Along the inner edge 
the lips have a band with a finely striated surface. There are no indications, however, of 
true teeth. 
The oesophagus is muscular, slightly bulbous, and is 15 mm. long. 
Re- « 
HErk.RA.KtS NOUlDit 
A=:mouth parts. B^veDtreQ aspect of tail of male shotslDg papillae 
In the male the posterior end of the body is provided with narrow, thick, cuticular 
expansions, extending forwards to disappear at about 0 8 mm. from the tip of the tail. Upon 
the area of the ventral surface thus enclosed three anatomically important features are seen. 
The genital opening 0'25 mm. forward from the tail-tip, and, again a further 0'15 mm., the 
ventral sucker with chitinous ring-like edge. The third and specifically most distinctive 
