WYMAN, ON THE FORMATION OF INFUSORIA. 109 
these last-mentioned cells have any definite relation to the 
muscular structure, I have as yet been unable to determine. 
Having thus described the anatomy, general and micro- 
scopical, of the nervous system of the Lumbricus, a question 
very naturally arises—to what portion of the nervous system 
in man and the higher mammalia is the above type of nervous 
system analogous? The supra-cesophageal ganglia, both from 
their position and structure, are evidently the analogues of 
the cerebral hemispheres, but the ventral chain is not so easily 
disposed of. Some anatomists regard it as being analogous 
to the spinal cord, while others consider it as belonging to 
the sympathetic system. It would be foreign, however, to the 
present paper for me to enter at length into this question. I 
may here, however, state my opinion, and reserve my reasons 
for holding such an opinion for a future communication. 
The supra-cesophageal ganglia I am inclined to regard as 
analogous to the cerebrum of man and the higher mammalia 
in a very rudimentary state, and with the spinal cord unde- 
veloped. The ventral chain of ganglia I regard as belonging 
to the sympathetic system; the lateral quadrepolar cells 
being the analogues of the lateral ganglia in man; the cen- 
tral multipolar cells representing the central plexuses in the 
human subject. The flat, ribbon-like collar surrounding the 
cesophagus I believe to be the vagus nerve largely developed. 
Viewing the supra-cesophageal ganglia as an undeveloped cere- 
bro-spinal system, and the ventral chain as a well-developed 
sympathetic system, and comparing these two portions of the 
nervous apparatus as we ascend in the scale of animal life, 
it will be found, as a rule, that as the cerebro-spinal system 
increases in size and development, the ventral or sympathetic 
system decreases in proportion. 
ExprerRmMEents on the Formation of InFusorta iz BorLep 
Soxtutions of Orcanic Marresr, enclosed in hermetically 
sealed vessels, and supplied with pure air. By Jurrries 
Wyman, M.D., Hersey Professor of Anatomy in Harvard 
College. 
(From ‘Silliman’s Journal.’) 
PastEuR in his admirable researches on fermentation has 
brought forward experimental evidence to show that this 
process depends upon the presence of minute organisms in 
the fermenting fluid, and that the source of all such organisms 
