NEMATODA 207 



Strongylidae in the Intestine of the Dog. (a) Ankylos- 

 toma canina (Uncinaria trigonacephala; Dochmins trigona- 

 cephalus] . This parasite is small, being 10 to 15 mm. 

 long, the body white, mouth slightly expanded, the ven- 

 tral border or jaw terminating in four hook-shaped pro- 

 jections arranged in pairs, and usually called lips, by means 

 of which the worm attaches itself to the mucous membrane. 

 Within the mouth on the median line is a conical tooth-like 

 projection, on the summit of which a gland opens. On the 

 dorsal border there are in addition, two small straight teeth. 

 The tail of the male is expanded, while that of the female 

 terminates in a blunt point. The vulva is at the posterior 

 third of the body. Ova ovoid, 74 to 84 microns long by 48 

 to 54 microns broad. 



(6) Uncinaria stenocephala (Anhylostomum stenocephalum). 

 -This species of the strongylidse is smaller than the above 

 and less common. Body is thinner than that of the Anky- 

 lostomum canina. Head is narrow, buccal capsule having on 

 each side of its ventral aspect a sharp bordered "lip," back 

 of which is a hook-shaped tooth. The dorsal border has 

 no teeth. The male is 6 to 8 mm. long, female 8 to 10 

 mm. Ova ovoid, 63 to 67 microns long by 32 to 38 microns 

 broad. 



Strongylidse in the Intestine of the Ca,t.Ankylostomum 

 trigonacephalum. This parasite has been described under 

 the name of Dochmius balsami. It is almost, if not, identical 

 with the Ankylostoma canina of dogs as described above. 

 They often occur in larger numbers in cats, and may 

 localize at one particular part of the small intestine. 



Strongylidae in the Intestine of the Rabbit. (a) Strmigy- 

 hrides longus.1\\is species inhabits the anterior part of the 

 small intestines. It is a very small worm, and the mouth 

 has no hooks. Eggs are ovoid, 40 microns long and 20 

 microns wide. 



(b) Strongylus strigosus. This is a rare species and inhabits 

 the cecum and colon of the rabbit. In rabbits the parasite 

 has not been known as yet to produce any serious pathogenic 

 conditions. 



