134 PARi\SITOLOGY. 



brane so that this acts as a portal of entry of many 

 harmful bacteria. 



The author has recorded three cases of Sclerosto- 

 mum equinum in the spermatic arteries. Two of these 

 cases were from cryptorchids one from a "straight" 

 colt. 



From the adult intestinal form the ova or embryos 

 pass out to the external world with the feces where 

 if not already hatched they do so in a short time if 

 climatic conditions are favorable. Damp or even wet 

 pastures favor this intermediate stage and parasitisms 

 is more prevalent in horses, asses or mules pastured 

 on such grounds. Thus contaminated food and water 

 serves as carriers of the infection. 



Strongylus Vasorum (Vas — a vessel). 

 Distribution. — Reported in Europe. 



Description. — The worm is thread-like in calibre and 

 white or pink in color; the mouth is nude; the male is 

 provided with a short, bilobate caudal pouch and two long 

 spiculae; the male is two-fifths of an inch in length, the 

 female one-half inch. 



Animal Infested. — The dog. 



Farts Infested. — The adult infests the blood-vessels, 

 especially of the right side of the heart, and the pulmon- 

 ary artery; the larva infests the lungs. 



Condition Produced. — The ovum or embryo becomes 

 lodged in the small arteries of the lungs, and it produces 

 thrombosis. Its presence also causes a small granule or 

 tubercle to form in the lung tissue; in the center of the 

 tubercle is found the ovum or embryo, surrounded by 

 epithelial, embryonic and giant cells, as found in the 

 tubercles caused by the bacillus of tuberculosis. 



Symptoms. — Sudden dyspnoea, anemia, emaciation and 

 oftentimes cough. Ova or embryos may be expelled by 

 the fits of coughing. 



