182 
On the Regeneration Hypothesis. 
and electricity are very different. The nerve current, it has been 
proved, traverses not more than from 100 to 300 feet in a second 
of time, while electricity, it is known, travels at the rate of many 
thousands of miles in a second. The deduction is, however, de- 
fective, and in many ways. I would remark that — 
1. A comparison is made between the passage of the nerve 
current along a moist tissue and the passage of electricity along a 
copper wire. 
2. It must he borne in mind that it is certain that if the nerve 
current were electricity, it would travel very slowly along such a 
structure as the axis cylinder. 
3. The rate at which a single axis cylinder transmits a current 
of electricity has not yet been ascertained, hut this is exactly the 
information we need before we can arrive at a correct conclusion on 
the subject. 
4. The rate at which electricity travels through such a moist 
tissue as the axis cylinder, has to he ascertained and compared with 
the rate at which nerve energy is known to travel. 
I will only remark, in conclusion, that no one has yet suc- 
ceeded in showing that the nerve current is not electricity, while 
a great number of well-ascertained facts, especially those known in 
connection with the structure and action of the electrical organs of 
certain of the lower animals, strongly support this inference. 
Y .—On the Regeneration Hypothesis. 
By Dr. Louis Elsberg, of New York. 
The more the knowledge of the facts spreads on which Lamarck’s 
Development theory and Darwinism rest, the more the need of a 
logical conception as to the propagation of organisms becomes felt. 
Without detailing other attempts in this regard I desire to present 
a brief account of my hypothesis of regeneration. Its fundamental 
proposition is the following : — The germ of every derivative living 
being contains {resp. consists of) plastidules of its whole ancestry. 
As is well known, Prof. Haeckel has given the name of 
Plastids* to the four elementary forms of living matter, viz. cells 
with and without investing membrane, and cytodes with and with- 
out investing membrane. Adopting the name plastid, and without 
entering upon the vexed questions connected with the atomic 
hypothesis, I use the term “ plastidule ” to designate the smallest 
conceivable actually existing — the almost infinitely subdivided — 
particle of the matter composing a plastid. 
* As move conformable with the genius of the English language, I have 
omitted the final “ e ” of the German word Plastide , and of course in pronuncia- 
tion place the accent on the first syllable instead of on the second. 
