MUTILATIONS AND THE LIKE 229 



of the head no true horn, but a small nucleus of bone hanging to 

 the skin. It may have been that an inborn weakness, which led 

 to the ulceration of the mother-cow's horn, took a slightly different 

 expression in the calves. 



Dr. J. W. Ballantyne quotes Kohlwey's experiments on pigeons : 

 " He cut off the posterior (first) digit of the foot, and the mutilated 

 bird got into the habit of turning the fourth digit backwards and 

 using it in perching ; he got no descendant of these mutilated birds 

 without a posterior digit, but he got a descendant of one of the pairs 

 with its fourth digit turned backwards like the first. The mutilation 

 was not transmitted, but the physiological adaptation to meet it was." 

 Is it sufficient to regard this simply as a coincident variation ? 



Some of the best cases are those in which a morbid change was 

 associated with the loss or injury of a particular structure. A cow 

 loses its left horn by suppurative inflammation ; it has subsequently 

 three calves in which the left horns were abortive (Thaer, 18 12). 

 But it may be that the original loss was due to a weakness of germinal 

 origin. 



Prof. W. H. Brewer (1892-3) is responsible for launching a 

 large number of rather unseaworthy instances of modification-in- 

 heritance. Inter alia, he tells the story of a pure-bred game-cock 

 who lost an eye in a fight, and transmitted his loss. While the 

 wound was very malignant, he was turned into a flock of game-hens 

 of another strain, and " a very large proportion of his progeny had 

 the corresponding eye defective." " The chicks were not blind when 

 hatched, but became so before attaining their full growth. The 

 hens afterwards produced normal chickens with another cock." 



Of great interest is the statement made by some botanists that 

 some peculiar effects on trees due to mites, ants, etc., are trans- 

 mitted. Thus Lundstrom says that the little shelters (acaro- 

 domatia) produced on the leaves of lime-trees, etc., by mites, 

 may appear when there are no mites. But are there ever no 

 mites ? 



But, admitting that there are some puzzling cases, we cannot 

 avoid the general conclusion that as regards mutilations, amputa- 

 tions, wounds, and deformations, the case for the affirmative is 

 not strengthened by further inquiry. 



