555 



An Alleged Specific Instance of the Transmission of Acquired 

 Characters. — Investigation and Criticism* 

 By T. Graham Brown (Carnegie Fellow). 



(Communicated by Prof. C. S. Sherrington, F.E.S. Eeceived December 9, 1911, — 

 Read February 15, 1912.) 



(From the Physiological Laboratory of the University of Liverpool.) 



CONTENTS. 



I. — Historical Note 555 



II.— Experiments Concerning the Nature and Cause of the- Brown-Sequard 

 Phenomenon — 



a. The Views held by previous Observers 559 



b. The Occurrence of the Phenomenon in Relation to Trophic Changes 



in the Feet 560 



c. The Occurrence of the Phenomenon in Relation to Changes in the 



Great Sciatic Nerve 561 



d. Occurrence of the Phenomenon in a Case of Accidental Injury to 



the Foot 562 



e. Phenomena under Narcosis in the Guinea-pig and other Animals ... 563 

 /. Phenomena in Decerebrate and in Decapitate Animals 564 



III. — Conclusions Concerning the Nature of the Brown-Sequard Phenomenon ... 566 



IV. — Conclusions Concerning the Cause of the Brown-Sequard Phenomenon 567 



V. — Experiments on Transmission of the Phenomenon— 



a. Experiments on Guinea-pigs 571 



b. Experiments on Rats 571 



VI. — Conclusions Concerning the Alleged Transmission of the Brown-Sequard 



Phenomenon 572 



VII.— Summary 573 



Table of References 577 



I. Historical Note. 



The adherents of the theory of the transmission of acquired characteristics 

 rely upon a comparatively small amount of experimental evidence. Of that 

 evidence, " Brown-Sequard's epilepsy " in guinea-pigs is considered an 

 important part. 



Brown-Sequard discovered that guinea-pigs develop " epilepsy " after 

 certain lesions of the nervous system, and he stated that the young of such 

 " epileptic " animals may also exhibit the " epilepsy," although this state does 

 not occur in normal individuals. 



* The expenses of this research have been defrayed by a grant from the Carnegie 

 Trust. The experiments in part were performed in the Physiology Laboratory of the 

 University of Glasgow. 



