To control marshy ground: 
The marshes should be drained, if possible, so that the snails may 
be gotten rid of. 
It has been noticed that sheep which pasture on salt marshes are 
not fluked; accordingly dressings of salt, to which lime may be added, 
should be spread over the pasture, as salt and lime will destroy the 
embryos, the encysted cercariae, and the snails. . . . 
Lime will destroy the grass for immediate use, but will in some 
cases be advantageous to the soil. . . . 
If the marshy ground cannot be controlled, place the animals on 
higher ground. (This also does not generally apply to Hawaiian con- 
ditions, since in many places the constant moisture of the higher alti- 
tudes renders the conditions ideal for the life of the snail and the 
development of the parasite.) 
To destroy the snail. — This may be done by draining the fields, thus 
depriving the snails of the conditions necessary for their development, 
or by the free use of salt and lime. 
General precautions to be taken: 
It is known that salt will kill the cercariae; accordingly if salt is 
given to the animals they stand a better chance of escaping hepatic 
(fluke) infection, even if the germs are swallowed, not only because 
this substance kills the young flukes, but because it aids the animals 
in their digestion. (The value of feeding salt to fluke-infested stock 
has been proved by experiments noted in this connection but which 
are not quoted.) 
A daily allowance of dry food should be given. 
If fields are overstocked the animals will be obliged to graze very 
close to the ground, and will thus be more liable to become infected, 
accordingly, in order to prevent this close grazing, fields should not be 
overstocked. 
Animals should not be left too long upon the same pasture. 
Raised watertanks .should be placed in the pastures so that the herds 
will not be forced to drink from pools, etc. As it is difficult for snails 
to get into such drinking tanks, there will be little fear of infection 
from tanks of this sort. 
Tared G. Smith, 
D. L. Van Dine. 
Honolulu, T. H., January 5. 1905. 
EXPLANATION OF PLATE I. 
The Life-Cycle of the Liver-Fluke, Distoma hepaticum. A. — Egg of 
the common liver fluke containing a developed embryo. Magnified 130 
diameters. B, — Egg after hatching. C,— The ciliated embryo ae it 
appears before attacking the fresh-water snail. Magnified about 350 
diameters. D, — A sporocyst which has developed from the embryo 
within the body of the snail, in which may be seen the developing 
rediae. Magnified 200 diameters. E, — Redia in the liver of the snail 
with developed cercariae. Magnified 150 diameters. F, — Encysted 
cercariae on a portion of a grass stalk. Magnified 10 diameters. 
G, — Young of liver fluke which has developed from cercariae in liver 
Of stock. Natural size. H, — Adult liver fluke from liver of stock. 
Natural size. I and J, — The fresh-water snail, Limnaea oahuensis, an 
intermediate host of the liver fluke. Slightly enlarged. (A, B, C, G 
and H copied from Neuman's Parasites and Parasitic Diseases of 
Domesticated Animals. D, E, F, I and J copied from Bulletin 19, 
Bureau of Animal Industry, U, S. Department of Agriculture.) 
