438 STUDIES IN GENERAL PHYSIOLOGY 



dragged along in the movements of the anterior portion of 

 the animal as though it was an inanimate mass. A pecu- 

 liarity exists here, of course, which Friedlander 1 and P have 

 observed in worms, in a more pronounced way, namely, that 

 a sort of indirect co-ordination may occur between the 

 anterior and posterior portions of the animals in spite of the 

 division of the cord. Thirdly, that division was perfect was 

 proved through galvanotropic experiments. The constant 

 current brings about associated changes in the position of 

 the anterior and posterior extremities in the normal animal, 

 while these associated changes in position do not occur in an 

 animal in which the spinal cord has been severed. 3 



These observations show without a doubt that, in spite of 

 the division of the spinal cord, metamorphosis occurs as 

 though the central nervous system were intact. If Tornier's 

 idea were strictly correct, one would expect that the division 

 of the central nervous system would be followed, not only by 

 a division of the motor and sensory functions of the anterior 

 and posterior part of the animal, but also by a division of the 

 morphogenetic functions. Since this is, however, not the 

 case, this conclusion at least may be drawn, namely, that the 

 morphogenetic functions in animals with a central nervous 

 system do not depend so strictly upon the central nervous 

 system as do the motor and sensory functions. 



The objection might be raised that the central nervous 

 system of Amblystoma is not highly enough developed to 

 decide the question of the influence of the spinal cord upon 

 the formative processes. Observations are, however, at hand 

 which leave no room for doubt that conditions are similar in 

 the dog. Groltz has found that all the individual milk-glands 

 in a pregnant bitch develop equally after division of the 



1 Biologtsches Centralblatt, Vol. VIII. 



zpfliigers Archiv, Vol. LVI. 



3LOEB UND QAEKEY, II, ibid., Vol. LXIV. 



