Volume VII 
OCTOBER, 1914 
No. 3 
f 
A NOTE ON THE PRESENCE OF OSTERTAGIA 
TRIFURCATA IN THE ABOMASHM OF A 
SHEEP IN ENGLAND. 
By STORRAR CAVE, B.A. 
(With 3 Text-figures.) 
While examining the strongyles of the fourth stomach of an 
ewe belonging to the Cambridge University Farm, which had been 
slaughtered for post-mortem examination, numerous male and female 
Ostertagia circ-umcincta {Strongylus cervicornis of MacFadyean) were 
found. A few specimens of Haemonchiis contortus were also present. 
Whilst mounting specimens of the male Ostertagia circumcincta, it was 
noticed that another strongyle was also present in the stomach, which 
resembled this species markedly, both in size and general form, especially 
in the bursa—but it differed in the spicules and gubernaculum, the 
former of these, instead of being long, narrow and bifid at their posterior 
extremities, as in Ostertagia circumcincta, are short, fairly broad and 
trifid posteriorly. The gubernaculum is narrow and lozenge-shaped. 
After more careful examination there was no doubt that this other 
strongyle is identical with Ostertagia trifurcata —a species created by 
Ransom of the U.S.A. Bureau of Animal Industry in 1907, for a worm 
found in the fourth stomach of many sheep and goats in America. 
According to this author this species is always associated with Ostertagia 
circumcincta. No females of the worm were found by him, and I also 
have found none. 
Specific Characteristics and Description. 
The worm is 8-2 mm. long, gradually tapering in thickness from 
18/i, at the head to a maximum of 110 p, just in front of the bursa. 
Two lateral cervical papillae 320 p from the anterior end are present; 
Parasitology vn 14 
