576 Mr. Graham Brown. Alleged Specific Instance of [Dec. 9, 



to produce a reaction directed to the area of skin in which the stimulus is 

 present, the reaction rapidly irradiates into the more excitable arcs. Thus 

 efficient grooming of the skin will be prevented. Degenerative changes 

 may then appear in the " epileptogenous zone," and these may tend to raise 

 still further the excitability of the reflex by acting upon the excitation side 

 of the neural balance. 



12. If this is the nature and causation of the Brown-Sequard pheno- 

 menon, it is, at any rate, very difficult to see how it is transmitted to the 

 offspring. 



13. Experiments are quoted in examination of the alleged transmission 

 of the phenomenon to the offspring in guinea-pigs and in rats — the presence 

 of the " incomplete " phenomenon being shown for the rat. 



14. As regards a state of raised excitability of the scratch-reflex in the 

 young which survived these are negative. But emphasis is not placed upon 

 these merely negative results, especially as they are comparatively small in 

 number. 



15. Of peculiar significance are three observations. In the first place, 

 guinea-pigs which had a " trophic " change in the foot, as a result of the 

 severance of the great sciatic nerve, have been seen repeatedly to nibble 

 the feet of other guinea-pigs in the same cage which also had this change 

 in the foot from the same causes. 



16. The second observation is that accidental injury to the toes in a 

 normal animal may be followed by the appearance of the Brown-Sequard 

 phenomenon. 



17. The third observation is that, in several instances, the young of 

 guinea-pigs which had the phenomenon present have been noticed to 

 have one or more toes eaten off by the mother. These young were 

 probably alive at birth, but were dead shortly after. In some cases 

 injury to the toe or to the foot was the only mutilation produced by the 

 parent. 



18. These three observations — that the phenomenon may be produced 

 by accidental injury to the toes, that the parents evidence an abnormal 

 habit of nibbling not only their own feet (in the amesthetic parts) but 

 also the feet of other similar guinea-pigs, and that the guinea-pigs may 

 nibble the feet of their young — seem almost to prove a suggestion which 

 has been put forward by Morgan, and seems to be hinted at by Taft. 



19. It may be admitted that Brown-Sequard and others have actually 

 seen the presence of the phenomenon in the offspring of these guinea-pigs. 

 But it may be supposed with every degree of probability that this was due to 

 accidental injuries inflicted upon the young by their parents. The statement 



