73 
of nerves in the placenta. 
the pubes give off a branch, which takes a circuitous course 
towards the lateral portion of the bladder, and the extre- 
mity of the oviduct. The continuation of the aortic, or ab- 
dominal plexus, in union with some branches of the sacral 
nerves, forms on each side of the pelvis a kind of plexus, 
which distributes branches to the cloaca and lower portion of 
the oviducts. 
“ The nerves corresponding with those which have been 
described in the frog, run almost entirely in straight lines, 
instead of having the intricate reticulated texture of the vis- 
ceral nerves in hot blooded animals. The ganglia are in- 
distinct, and the fibres that compose them resemble those 
of the muscular, more than visceral nerves.” 
At the time I was appointed to give this Lecture, I had com- 
pleted an investigation, in which was traced to its origin the 
formation of the brain and spinal marrow in the ovum of the 
frog, and intended, upon this occasion, to have laid my obser- 
vations, illustrated by a series of drawings made by Mr. 
Bauer, before the Society, but having been so fortunate as 
to discover the nerves of the placenta, I did not hesitate in 
giving this discovery the preference, and taking the earliest 
possible opportunity of communicating it to the Society. 
Now that it is known by the discovery of the nerves in the 
placenta that the brain of the child, as well as every part of 
its body, is connected by the medium of nerves with the 
brain of the mother, we are led to understand the degree of 
dependence in which the foetus is kept during the whole 
time of utero gestation. 
The small pox being in some instances communicated from 
the mother to the child, which has until now been consi- 
L 
MDCCCXXV. 
