over a period of 12 days; it passed 3 cylicostomes; it was then put on 
a chenopodium treatment which removed all the cylicostomes (1242), 
95 per cent of the Strongylus (78 out of 82) and 25 per cent of the 
ascarids (1 out of 4). (The papers in question do not clearly bring 
out the fact that the ascarid passed after chenopodium and not after 
iron sulphate.) Another horse was given 2 drams of tartar emetic in 
a mash daily for 5 days; it passed 10 cylicostomes, 1 Strongylus, 1 
pinworm, and 1 ascarid; postmortem it had 5474 cylicostomes, 312 
Strongylus and 11 ascarids; the small intestine showed numerous 
petechiae and ecchymoses which were apparently due to the drug. 
These experiments indicate clearly that iron sulphate or tartar 
emetic given in a mash for several days in the amounts stated are 
quite ineffective against cylicostomes, Strongylus and ascarids. Iron 
sulphate is also ineffective against pinworms and the efficacy shown 
by tartar emetic against pinworms does not' warrant its use in view 
of the lesions caused by this drug and the greater efficacy shown 
against cylicostomes and Strongylus by chonopodium, which is equally 
effective against pinworms and is therefore the drug of choice for re¬ 
moving worms from the large intestine of the horse. 
CARBON BISULPHID AND CHENOPODIUM 
The two drugs which are most effective in removing worms and 
other parasites from the digestive tract of the horse are carbon bi- 
sulphid, which will remove all or practically all of the ascarids and 
bots, and chenopodium, which will remove all or practically all of the 
cylicostomes, Strongylus and pinworms from the large intestine. These 
drugs should be administered in capsules. It is hardly necessary to tell 
veterinarians how to administer capsules to horses. Some prefer the 
balling gun, which is a very satisfactory instrument if properly used 
and which affords safety to the operator from injury to the hands. 
Others prefer to give a capsule by hand, and veterinarians in general 
are familiar with the necessity for holding the hand with the thumb up 
instead of with the palm down in order to avoid injury from the 
animal’s teeth. Skill with the balling gun or hand is largely a matter 
of practice, and either method is satisfactory with a skilled operator. 
PURGATION AFTER ADMINISTRATION 
No purgation is necessary or advisable after carbon bisulphid, but 
it is advisable and desirable after chenopodium. Hall, Wilson and 
Wigdor used a quart of castor oil b}' drench after chenopodium. 
Drenching is regarded as rather risky business, but the safety factor in 
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