MR. T. SNOW BECK ON THE NERVES OF THE UTERUS. 
229 
derived from the lumbar nerves, through the medium of, what might be called, the 
abdominal splanchnic nerves (19.19, &c.,and 14.14, &c.). The branches of the lower 
part of this plexus all converge to one point, viz. the root of the inferior mesenteric 
artery ( i ), where the association of the gelatinous and tubular fibres occurs, previous 
to the branches being given off to the large intestines, and to the inferior aortic 
plexus. From the exact similarity which exists between the semilunar ganglion and 
the inferior part of the superior aortic plexus, in their formation and constitution, it 
would not be stretching analogy too far to say, that a second semilunar ganglion 
exists in this situation, having its elements more apart, and being diffused over a 
larger space. Indeed these aortic ganglia (21.21, &c.) offer a good demonstration of 
the formation of the more dense structure of the semilunar ganglion (3.3, &c.). The 
elements of the semilunar ganglion are, the tubular fibres derived from the inter- 
costal nerves, through the medium of the splanchnic nerves (1.1. and 2.2), and the 
gelatinous fibres derived from the sympathetic ganglia. And the reason of so large 
an amount of nervous matter being collected in this situation is, no doubt, from its 
being a common point whence large and numerous branches pass off to the different 
viscera. The elements which enter into the formation of the lower part of the superior 
aortic plexus are exactly similar to those which form the semilunar ganglion ; viz. 
tubular fibres derived from the lumbar nerves through the medium of the abdominal 
splanchnic nerves (19.19, &c., 14.14, &c.), and gelatinous fibres from the sympathetic 
ganglia (21.21, &c., 15.15). And the reason why a smaller amount of nervous 
matter exists here than at the semilunar ganglion is, that the branches which pass 
from it are much less numerous. However, in estimating the branches which pass 
from this point, we must take into account not only those which pass out with the 
inferior mesenteric ( i ) and superior heemorrhoidal (k) arteries, but also the branches 
which form the inferior aortic plexus (22.22) ; for this latter plexus is constituted 
in a manner very different from the superior aortic plexus. Whilst the superior aortic 
plexus may be said to form a plexus distinct in itself, in which the tubular and gelati- 
nous fibres become associated together to form the branches of the sympathetic, the 
inferior aortic plexus is merely the continuation downwards of some of these branches, 
so formed, previous to their dividing to form the two lateral hypogastric plexuses. 
22.22.22. Branches of the sympathetic which accompany the inferior mesenteric 
artery (7). 
23.23.23. Branches of the sympathetic which accompany the superior hsemorrhoidal 
artery (k, /). They proceed from a common point with the preceding branches 
(22.22), and like them are composed of gelatinous and tubular fibres. 
24.24. Branches which accompany the divisions of the superior hsemorrhoidal 
artery, before the formation of the pelvic plexus (61.61, &c.). 
25.25. Branches which pass downwards and join the posterior part of the pelvic 
plexus (61.61, &c.). 
26.26.26.26. The inferior aortic plexus, consisting of branches of the sympathetic 
