ON A NEW ACARUS OF THE HORSE. 
283 
science, that the entozoa are not only supported as a great 
family, but have also their diversities of race kept up by 
their constant migrations from one friendly animal to 
another. 
We have evidence also that the cholera-poison, whatever it 
may be in nature, is a thing; we know somewhat how it 
moves, we conceive that it makes water its chief vehicle, that 
it passes off in the excretions of the cholera patient, and that 
its pathological, or better, perhaps, its physiological effects, 
are analogous to those produced by some of our more active 
cathartic agents. 
Hitherto we have gone, and no further. Beyond is the 
open sea and land unknown. Whoever, setting forth towards 
this unknown, shall, by design or accident, make new land, 
need not fear for his fate in history ; a new world would not 
be a greater discovery, nor the fame of Columbus remain 
without its rival. Neither need we cease to live in hope for 
true discoveries in this direction. We are making immense 
strides in physiological research, and if in these the epi- 
demiologist shall patiently follow, his success is secure. The 
question of the transmission of disease by diseased food is 
the topic of the day, and affords a grand opening for such 
investigations as have been glanced at above . — Medical Times , 
April 1 1, 1857. 
ON A NEW ACARUS OF THE HORSE CAPABLE OF TRANS- 
MITTING THE ITCH OF THAT ANIMAL TO MAN. 
By MM. Bourguignon and Delafond. 
Hitherto, the cases of transmission of the itch of horses 
to man has been involved in doubt. Seeing that the known 
parasite of the itch of horses could not live on the human 
species, and that the authors who have expressed themselves 
in the affirmative, have never demonstrated scientifically that 
the malady transmitted was really due to the presence of an 
acarus proceeding from the horse. Starting from the data 
furnished by entomology, we were warranted in denying to 
the known parasites peculiar to the herbivora, and to the 
horse in particular, the faculty of transmitting the itch. Ob- 
servation has just enabled us to trace effects to their causes, 
and to explain everything. 
