232 TRANSMISSION OF ACQUIRED CHARACTERS 



Muscular atrophy of the thigh and leg followed section of the 

 sciatic nerve, and this was also observed in the offspring. 



After cutting the restiform body one eye suffered deterioration ; 

 this was seen in the offspring in one eye, or even in both. 



In general, the morbid conditions may affect both sides in the 

 parents and only one in the offspring, or vice versa, or the side 

 affected may be different. 



One generation may be skipped, but the duration of transmission 

 was in some cases traced through five or even six generations. 



The females seemed better able to transmit morbid states than 

 the males. 



As to the frequency of transmission, some inherited result was ob- 

 served in more than two-thirds of the cases. 



Brown-Sequard's results were partly confirmed by his assistants, 

 Westphal (1871) and Dupuy (1890), by Obersteiner (1875), and by 

 Romanes (1895). Dr. Leonard Hill divided the left cervical sympa- 

 thetic nerve in a male and a female guinea-pig, and thereby produced 

 a droop of the left upper eyelid. Two offspring of this pair ex- 

 hibited a well-marked droop of the upper eyelid. " This result is 

 a corroboration of the series of Brown-Sequard's experiments on the 

 inheritance of acquired characters." 



Facts to be noted, which dispose of a Number of Criticisms. — 

 It is stated that the so-called " epileptic " state may also be induced 

 in the dog by injury to the cerebral cortex, and may, in this case also, 

 reappear in the offspring. If this be so it shows that we have not 

 to deal with a tendency peculiar to guinea-pigs. 



It is stated that the " epileptic " condition does not occur spon- 

 taneously — i.e. apart from injury to the nervous system — in guinea- 

 pigs. Therefore the interpretation of the apparent inheritance as 

 being due to a fresh variation which happened by coincidence to 

 resemble the parental state, is inadmissible. 



As the tendency to " epileptic " fits (which do not last long) was 

 seen only in the offspring of animals which had been operated on, 

 and was manifested only after appropriate stimulus, especially after 

 irritating an " epileptogenic " zone behind the ear on the same side 

 as the original injury, we must pass by Galton's suggestion (1875) 

 of the possibility of reappearance through imitation. Even if it 

 be allowed that there is a certain infectiousness in " fits," this would 

 not apply to the loss of toes, the diseased state of the ear, the pro- 

 truding eyes, and so on. 



