168 Dr. Haighton’s experimental Inquiry 
and controversy, the arbiters of science have not yet acknow- 
ledged a victor on either side. 
The advocates for the first opinion allege, that the semen 
has been seen both in the uterus and tubes, and quote as their 
authority the observations of Morgagni for the former, and 
Ruysch for the latter. When seen in this last situation, some 
have thought that it was conveyed thither by the muscular 
power of these parts in the manner of a peristaltic motion, be- 
ginning at the uterus and ending at the fimbriated termina- 
tion of the tube ; and when at this last, it was supposed that 
the semen was applied to the surface of the ovaries, and im- 
pregnated them by actual contact. 
Though I shall prove that this hypothesis is altogether 
visionary, yet prima facie it is far from carrying with it the 
characters of absurdity. There is nothing repugnant to reason 
in contending for what analogy seems to favour, particularly 
when the subject is thought beyond the reach of demonstration 
or proof. And the analogy favourable to this opinion has pro- 
bably been taken from the impregnation of frogs and toads, in 
which process we are told, on the authority of Roesel, Swam- 
merdam, and Spallanzani, the ova are impregnated by the 
male as they are passing from the body of the female ; and that 
in water newts the ova are impregnated even without copulation. 
Now here is an appearance of contact between the fecundating 
fluid and the ova. 
Again, on the other hand, the contact of semen with the 
ovaries has been thought improbable, from an analogy drawn 
from the vegetable kingdom ; for admitting the Linnaean doc- 
trine to be true, which contends for a necessity of sexual inter- 
course. in vegetables, it would be difficult to demonstrate to 
