THE GENERATIVE APPARATUS. 165 



CHAPTER VIII.— THE GENERATIVE APPARATUS. 



Section 1.— OF THE MALE. 



Oanis familiaris is a multiparous carnivorous mammal 

 with zonary placenta. His generative apparatus is 

 well developed, and in some respects, both anatomical 

 and physiological, very remarkable. The sexual instinct 

 runs high, and the act of copulation is prolonged. 

 The male animal is generally allowed to remain un- 

 castrated, and indulges in sexual intercourse freely, 

 frequently, and with little discrimination. His genital 

 organs occasionally suffer from excess, but probably 

 much more frequently from enforced abstinence. The 

 penis presents some marked peculiarities in structure, 



*■ 6 



Fia. 47. — Ob penis, after Stbangewaxs. 

 a, groove ; c, base; I, apex. 



such as an elevator muscular arrangement for the glans 

 and a penial bone or penien, through a deep groove in the 

 lower part of which the urethra runs. This bone varies 

 in shape in different breeds of dogs, but anteriorly termi- 

 nates in a cartilaginous point, and posteriorly is directly 

 continuous with the structure of corpus cavernosum. 

 Lauscat describes the peculiarities of the free part of the 

 penis of the dog in the following terms (as taken from 

 Chauveau's Anatomy ' translated by Fleming) : " The 

 penial bone almost entirely constitutes the base of all that 

 portion of the penis included within the sheath ; in addi- 



