that could possibly be parasitic, and there is a wide range of such 
lesions, should be examined for parasites. 
Excretory System 
The excretory system may harbor such parasites as kidney worms 
in swine and the giant kidney worm in dogs. Larval worms may also 
occur in the kidneys, but these can only be detected or suspected on 
the evidence of lesions produced by them. 
Circulatory System 
In the circulatory system parasites may be expected in the an¬ 
terior mesenteric artery of horses in the large majority of cases 
(Strongylus vulgaris in verminous aneurisms) and in the right heart 
and pulmonary artery of many dogs in parts of the southern United 
States. A number of parasitic worms use the blood stream as a 
distributing current during part of their life history and the blood 
may be examined for such forms by laking with three percent glacial 
acetic acid and centrifuging, the sediment being examined micro¬ 
scopically for worms. 
Skeletal, Muscular and Nervous Systems 
Parasites in the skeletal, muscular, nervous and reproductive 
systems are not very common, but such parasites as hydatids in 
bones, trichinae in swine musculature, the gid bladderworm in the 
brain of sheep, and flukes and roundworms in the oviduct of chickens 
warrant us in remembering the possibility of such occurences and 
in investigating wherever symptoms or lesions suggest the ad¬ 
visability of so doing. 
Examination of the Specimen 
The parasites collected should be washed in physiologic saline 
solution to remove mucus and other adherent material, otherwise this 
material will interfere with proper fixation and frequently appear on 
mounted material at points where it obscures important anatomical 
details. After washing, nematodes should be transferred, whenever 
possible, to hot 70 percent alcohol, in which they usually straighten 
out in a satisfactory position for subsequent examination. Tape¬ 
worms and flukes are killed in a very satisfactory manner in equal 
parts of 70 percent alcohol and a saturated aqueous solution of cor¬ 
rosive sublimate, to which is added one percent glacial acetic acid. 
This may be used cold, or better, at a temperature of 70 to 80° C. 
9 
