t 2 53 3 
\ 
XXIV. Obfcrvathns tending to fiew that the Wolf, Jackal, and 
D °g< are all of the fame Species, By Jolm Hunter, FJq. 
F. R. S. 
P.ead April 26, 17S7. 
r jj ' II E true diftindlion between different fpecies of animals 
JL muff ultimately, as appears to me, be gathered from 
their incapacity of propagating with each other an offspring 
capable again of continuing itfelf by fubfequent propagations : 
thus the Horfe and Afs beget a Mule capable of copulation, 
but incapable of begetting or producing offspring. If it be 
true, that the mule has been known to breed, which muff be 
allowed to be an extraordinary faiff, it will by no means be 
fufficientto determine the Horfe and Afs to be of the fame fpe- 
cies ; indeed, from the copulation of Mules being very frequent, 
and the circumffance of their breeding very rare, I fhould 
rather attribute it to a degree of monffroiity in the organs of the 
Mule which conceived, not being thofe of a mixed animal, 
but thofe of the Mare or female Afs. This is not fo far-fetched 
an idea, when we confider that fome true fpecies produce mon- 
fters, which are a mixture of both fexes, and that many ani- 
mals of diffinct lex are incapable of breeding at all. 
If then we find nature in its greateff perfe&ion deviating 
from general principles, why may not it happen likewife in the 
produftion of Mules, fo that fometimes a Mule fhall breed 
from the circumffance of its being a monffer refpeTing mules ? 
Vol. LXXVII. P P * The 
