The Inheritance of Acquired Characters 53 



If a particular spot of the restiform body of the brain is 

 injured, a marked protrusion of the eyeball quickly follows. 

 The progeny of parents thus affected show also an abnormal 

 protrusion. Romanes also observed this, but he found that the 

 young show less protrusion than do the parents, and since the 

 amount of protrusion of the eyeball is variable in normal guinea 

 pigs, Romanes is not certain that there is anything more than a 

 coincidence in the cases that he observed. 



An injury to the restiform body may also cause dry gangrene 

 (and haematoma) in the ears. This disease may appear either 

 several weeks after the operation or even later. It affects, 

 Romanes says, usually the upper parts of both ears and may 

 gradually "eat its way down" until two thirds of the tissues of 

 the ears are affected. In the offspring from animals of this sort 

 a morbid condition of the ears may arise at any time in their 

 lives, even after they have become full grown. The disease 

 does not go so far as in the parents, and "almost always affects 

 the middle third of the ears." Romanes points out that this 

 particular disease never appears amongst guinea pigs unless 

 their own or their parents' restiform bodies have been injured. 

 Furthermore, he tested the possibility that the results are due 

 to contagion by inoculating "corresponding parts of the ears 

 of normal guinea pigs by first scarifying those parts and then 

 rubbing them with the diseased surfaces of the ears of muti- 

 lated guinea pigs." The disease was not communicated in 

 this way. 



Brown-Sequard found that after cutting the sciatic nerve (or 

 this and the crural also) the leg became anaesthetic, and the 

 guinea pigs would sometimes eat off two or three of their hind 

 toes. In the offspring of these animals he found sometimes 

 an absence of toes, or only a part of one or more of the toes 

 might be missing. The inheritance occurred in only one or 

 two per cent of cases. Romanes, who repeated the operation 

 through six successive generations, never obtained any results. 



Another outcome of injury to the sciatic nerve is to induce 

 "morbid states of the skin and hair of the neck and face in 



