HOKPHOLOGICAL STUDIES. 
207 
the main portion of each crauial ganglion iu the Chick, — of 
that portion which is not derived from the remains of the bran- 
chial sense organs. The rest of his researches, on the cranial 
and spinal ganglia of Elasmobranchii, Teleostei, Lizards, and 
Mammals, and on the spinal ganglia of the Chick, lead him to 
the same results as Balfour, Marshall, and others. His 
researches hence agree partially with my own for parts of the 
cranial ganglia of the Chick, but for all other types he has 
failed to see the true epiblastic origin of both cranial and 
spinal ganglia. 
Hoffmann (No. 36, pp. 45 — 49) while supporting Balfour’s 
views of the outgrowth of spinal ganglia from the cord, con- 
siders it probable that the posterior root ganglia of the cranial 
nerves of Teleostei arise from the epiblast beyond the limits of 
the neural plate, and before the closure of the latter. He did 
not prove that such was the case. 
In later researches (No. 37, p. 204) he again refers to the 
neural ridge, but says nothing of its origin. 
VI. The Growth of our Knowledge of the Independent 
Epiblastic Origin of the Peripheral Nervous 
System. 
The first conclusions on this question were arrived at by 
Gbtte (No. 22, p. 72) and Semper (No. 57, p. 256), both of 
whom stated that the lateral nerve has an epiblastic origin and 
arises pari passu with the growth of the lateral line as a 
differentiation of the epiblast. Gotte (p. 719) extended this 
mode of development to the nerves of the lateral sense organs 
of the head. These statements, on which doubt was cast by 
Balfour, were practically confirmed by van Wijlie (No. 60, p. 
35) and Hoffmann (No. 36, p. 89,) for Teleostei. I (No. 4) 
believed Balfour’s doubts to be well founded, but in two sub- 
sequent publications I was able to prove, for Elasmobranchii 
the accuracy of Semper’s account. Just before my paper on 
the origin of the cranial ganglia (No. 5) appeared Professor 
