74 DOMESTIC PIGS. Chap. IIL 



expected, seem favourable for tlie production or retention of 

 peculiar breeds ; thus, in the Orkney Islands, the hogs have 

 been described as very small, with erect and sharp ears, and 

 "with an appearance altogether different from the hogs 

 brought from the south." 14 



Seeing how different the Chinese pigs, belonging to the 

 Sus indicus type, are in their osteological characters and in 

 external appearance from the pigs of the S. scrofa type, so 

 that they must be considered specifically distinct, it is a fact 

 well deserving attention, that Chinese and common pigs 

 have been repeatedly crossed in various manners, with un- 

 impaired fertility. One great breeder who had used pure 

 Chinese pigs assured me that the fertility of the half-breeds 

 ■inter se and of their recrossed progeny was actually increased; 

 and this is the general belief of agriculturists. Again, the 

 Japan pig or S. ijliciceps of Gray is so distinct in appearance 

 from all common pigs, that it stretches one's belief to the 

 utmost to admit that it is simply a domestic variety ; yet 

 this breed has been found perfectly fertile with the Berkshire 

 breed ; and Mr. Eyton informs me that he paired a half-bred 

 brother and sister and found them quite fertile together. 



The modification of the skull in the most highly cultivated 

 races is wonderful. To appreciate the amount of change, 

 Nathusius' work, with its excellent figures, should be studied. 

 The whole of the exterior in all its parts has been altered : 

 the hinder surface, instead of sloping backwards, is directed 

 forwards, entailing many changes in other parts; the front 

 of the head is deeply concave ; the orbits have a different 

 shape ; the auditory meatus has a different direction and 

 shape ; the incisors of the upper and lower jaws do not touch 

 each other, and they stand in both jaws beyond the plane of 

 the molars ; the canines of the upper jaw stand in front of 

 those of the lower jaw, and this is a remarkable anomaly : 

 the articular surfaces of the occipital condyles are so greatly 

 changed in shape, that, as Nathusius remarks (s. 133), no 

 naturalist, seeing this important part of the skull by itself, 

 would suppose that it belonged to the genus Sus. These 



14 Rev. G. Low. ' Fauna Orcadensis,' p. 10. See also Dr. Hibbert's account of 

 the pig ot the Shetland Islands 



