Charles L. Boulenger 107 
Although vagina and uteri are well developed in all the specimens, these 
as yet contain no mature ova. 
In the majority of its characters this species very closely resembles certain 
species of Triodontophorus, and is only excluded from that genus on account 
of the absence of teeth in the mouth-capsule. The mouth is relatively smaller 
and the number of elements of the leaf-crowns considerably less than in any 
known species of Triodontophorus. 
On account of the small size of the type-specimens and the absence of ripe 
ova, these worms might be considered as young stages of some species of 
Triodontophorus. This seems to me highly improbable, the specimens 
before me have evidently undergone the final moult and are obviously almost 
fully developed even if they have not reached their complete size. Species of 
Triodontophorus at this stage have the capsule-teeth fully developed, 1 have 
seen these structures in specimens smaller than those described above. 
The absence of these teeth therefore makes it impossible to include the 
worms in the genus Triodontophorus in spite of their close affinity; T have 
therefore been obliged to regard them as the types of a new genus. 
REFERENCES. 
Boulenger, C. L. (1916). Sclerostome Parasites of the Horse in England. I. The Genera 
Triodontophorus and Oesophagodontus. Parasitology, viii. 420-439. 
(1917). Sclerostome Parasites of the Horse in England. II. New Species of the 
Genus Cylichnostomum. Parasitology, ix. 203-212. 
Lane, C. (1914). Bursate Nematodes from the Indian Elephant. Indian Journ. Med. Res 
it. 380-398. 
Leiper, R. T. (1911). Some new Parasitic Nematodes from Tropical Africa. Proc. Zool . 
Soc. 1911 (1), pp. 549-555. 
Looss, A. (1900). Notizen zur Helminthologie Egyptens. Ill. Die Sclerostomen der 
. Pferde und Esel in Egypten. Centralbl.f. Bakteriol. Abt. 1 , xxvii. 150-184. 
- (1902). The Sclerostomidae of Horses and Donkeys in Egypt. Rec. Egypt. Goit. 
School of Med. i. 25-138. 
Yorke, W. and Macfie, J. W. S. (1918). Strongylidae in Horses. 11. Cylicostomum rninutum 
sp. n. Ann. Trop. Med. Parasit. xi. 405-409. 
A.g.c 
An. 
Ru. 
Ca. 
C. p. 
D. c. 
D.g. 
R.l.c. 
hix. 
G.c. 
EXPLANATION OF LETTERI 
Appendage of the genital cone. 
Anus. 
Margin of the bursa. 
Wall of mouth-capsule. 
Cervical papillae. 
Dermal collar of genital cone. 
Dorsal gutter. 
External leaf crown. 
Excretory pore. 
Genital cone. 
NG IN TEXT-FIGURES 1—7. 
I.l.c. Internal leaf-crown. 
Ini. Intestine. 
L. p. Lateral papilla. 
M. c. Mouth collar. 
Oes. Oesophagus. 
Oe.f. Oesophageal funnel. 
Sm.p. Submedian papilla. 
Sp. Spicule. 
Va. Vagina. 
Vu. Vulva. 
