30 
Sclerostomes of the Donkey 
collection contained one male in a good state of preservation, whilst a number 
of others occurred in material which had evidently been dry at some period, 
the worms being greatly shrivelled and full of air-bubbles; the species of 
Strongylus could only be identified by dissecting out the mouth capsule after 
maceration with Eau de Javelle. The specific diagnosis is therefore based on 
six specimens only (3 dd and 3 $$). 
The occurrence of fully developed specimens of this form in the liver is 
a point of interest, immature specimens of S. equinus have been observed in 
this situation but are more commonly met with in the pancreas; stages of 
this species and of S. edentatus have also been found in the hepatic ligament 
(Railliet and Henry 1902, Railliet 1915). 
Fig. 2. Strongylus asini sp. n. Lateral view of male bursa, x 37. 
Genus Cylicostomum Railliet and Henry 1 
(= Cylichnostomum Looss). 
Cylicostomum adersi sp. n. 
A single male specimen of this worm was found in Mr Aders’ collection; 
the specific diagnosis is therefore based on this sex only. 
Specific diagnosis. Cylicostomum : A large species presenting much the 
same appearance as C. insigne Boulenger (1917). 
Head marked off from the body by a slight neck-like constriction. The 
mouth collar is comparatively narrow (Fig. 3). 
The lateral head-papillae do not project from the surface of the collar, 
submedian papillae short and leaf-shaped. 
The external leaf-crown consists of about 26 large pointed leaves sur¬ 
rounding the circular mouth-opening, the internal leaf-crown of double this 
number of similar but less conspicuous elements. 
1 In a recent paper (1917) I used Looss’ generic name for these worms, there seems however 
no doubt that the form Cylicostomum has priority. 
