such intervals as the life history of the worms indicates as appropriate, 
or as the clinical condition of the animal calls for it, or as the recur¬ 
rence of eggs in the feces shows the recurrence of infestation. 
PERIODS DURING WHICH WORMS ARE PASSED 
The impression is quite prevalent that almost all worms passed after 
an anthelmintic come away in the first 24 hours after treatment. This 
is not the case. They commonly come away for two or three days, 
and bots may pass for over 17 days after treatment. It is therefore 
unsafe to conclude that a treatment is a failure because worms did not 
come away during the first day after treatment. In the treatments 
given in this paper there is a statement as to the length of time worms 
have been observed to pass after treatment wherever such information 
is available. It is quite probable that worms come away under some 
circumstances for even longer periods than those given. 
EXAMINATION OF FECES FOR WORMS PASSED 
Worms embedded in a fecal mass are easily overlooked, especially 
by persons unfamiliar with worms. The careful veterinarian will dis¬ 
regard the statement of the farmer, stable hand or dog owner who 
assures him that no worms were passed after treatment. A glance 
at the feces or a casual poke with a stick or straw cannot be depended 
on to give accurate information. The most satisfactory method of 
examination is to screen the feces through a screen of suitable size 
to retain the worms, washing as much fecal matter as possible through 
the screens, and then examining the screen. If this cannot be done, the 
feces should be thoroughly picked apart in a good light and carefully 
examined. 
TREATMENTS FOR HORSE PARASITES 
Bets: Fast 18 hours. For a 1000-pound horse, carbon bisulphid 
in capsules; 1 dose of 22 cc. (6 fluid drams); or 2 doses of 15 cc. (4 
fluid drams) each with a two-hour interval between doses; or 3 doses of 
11 cc. (3 fluid drams) each with an hour interval between doses. No 
78 
