PARASITOLOGY. 109 
Bronchial or Pulmonic Strongylosis,—infestation 
of the bronchi or lungs. 
Gastric Strongylosis,—infestation of the stom- 
ach. 
Intestinal Strongylosis,—infestation of the intes- 
tines. 
Vascular Strongylosis,—infestation of the blood 
vessels. 
Renal Strongylosis,—intestation of the kidney or 
fat around the kidney with strongle. 
Wet seasons favor the development of the disease, 
as moisture insures the life of the embryo outside of 
the body of the animal. The disease is most preva- 
lent on low-lying and swampy lands. It may be 
spread by the ova or embryos being carried in the 
stream of water, or by infested animals being intro- 
duced into a herd; the animal becomes infested 
through contaminated food and water. It is probably 
necessary for these worms to pass out of the host in 
order to complete a portion of their life history. If 
the ova or embryos fall into water or moist places 
they may remain alive for several months, provided 
there is no putrefaction of organic matter. At the 
end of one week they have been noted to moult, 
After a second moulting they apparently become 
shriveled and remain in the skin. In this state they 
may resist desiccation, and possibly cold tempera- 
ture, for a long time. Upon being taken in by the 
host they become revivified and develop into adult 
worms. A weakened physical condition lessens the 
animal’s powers of resistance to the invasion of the 
parasites. 
