1302 CYCLOPEDIA OF LIVE STOCK AND COMPLETE STOCK DOCTOR. 



original traits of animals appear to be conflicting elements in their con- 

 stitution, either of which may, from its intensity, predominate in hered- 

 itary transmission. Pigs have been taught to point game, play cards, 

 and perform various tricks, but in the hereditary transmission of these 

 characters Nature has had a stronger influence than culture. There 

 seems to be reason to believe that such hereditary transmission is limited 

 to acquired peculiarities which are simply modifications of the natural 

 constitution of the race, and would not extend to such as may be alto- 

 gether foreign to it. From a practical point of view, however, the in- 

 heritance of acquired characteristics, so far as they are of any value, is 

 fortunately without apparent limit. Abnormal characteristics are fre- 

 quently hereditary, but they are not so likely to be transmitted as ac- 

 quired habits that are in harmony with the original peculiarities of the 

 animal. It is stated on good authority that animals that have been 

 branded in the same place for several successive generations transmit 

 the same mark to their offspring. Dr. Brown-Sequard, in experiment- 

 ing with guinea-pigs, observed that in those subjected to a peculiar op- 

 eration, involving a portion of the spinal cord or sciatic nerve, a slight 

 pinching of the skin of the face would throw the animal into a kind of 

 epileptic convulsions. When these epileptic pigs were bred together 

 their offspring showed the same predisposition without having been op- 

 erated upon, while no such tendency showed itself in a large number of 

 pigs bred from parents that had not been subjected to the operation. 



IV. The Law of Atavism or Striking Back. 

 Any peculiarity of an ancestor, more or less remote, whether of color, 

 form, habits, mental traits or predisposition to disease, may make its ap- 

 pearance in the offspring without having been observed in the parenti. 

 Numerous cases illustrative of this law are 'reported, and I have no doubt 

 many readers of this article can call to mind cases in their own experience. 

 Mr. Dawson reports the case of a pointer bitch having given birth to a 

 litter of seven puppies. Four were marked with blue and white, which is 

 so unusual a color with pointers that she was thought to have played false 

 with a greyhound, and the whole litter was condemned, but the gar.ie- 

 keeper was allowed to keep one as a curiosity. Two years later a friend 

 of the owner saw the young dog and declared that he was the image of 

 his old pointer bitch, Sappho, the only blue and white pointer of pure 

 descent which he had ever seen. This led to a close inquiry, and it was 

 proved that he was the gi^eat-great-grandson of Sappho, so that he had 

 only one-sixteenth of her blood in his veins. Goodale states that many 

 years ago there were a few polled cattle in the Kennebec Valley, but 

 t.hov finally became extinct. For thirty-five vAwra after the last of these 



