322 GENERATION. 



ered under the head of the seminal fluid ; but we may here 

 note that it has been thought by Kraus, that the prostatic 

 fluid has the important function of maintaining the vitality 

 of the spermatozoids. " The spermatozoa, in the absence of 

 the prostatic fluid, cannot live in the mucous membrane of 

 the uterus of mammalia ; but with its aid they may live for 

 a long time in the uterine mucus, often more than thirty-six 

 hours." 1 



Glands of the Urethra. Anterior to the prostate, open- 

 ing into the bulbous portion of the urethra, are two small 

 racemose glands, called the glands of Mery or of Cowper. 

 These have each a single excretory duct, are lined through- 

 out with cylindrical epithelium, and secrete a viscid, mucus- 

 like fluid, which forms a part of the ejaculated semen. Some- 

 times there exists only a single gland, and occasionally, though 

 rarely, both are absent. Their function is probably not very 

 important. 



The glands of Littre, found throughout the entire urethra, 

 and most abundant on its anterior surface, are simple race- 

 mose glands, extending beneath the mucous membrane into 

 the muscular structure, presenting here four or five acini. 

 As these acini are thus surrounded by muscular fibres, we 

 can readily understand how their secretion may be pressed 

 out during erection of the penis. They are lined throughout 

 with columnar or conoidal epithelium, and secrete a clear and 

 somewhat viscid mucus, which is mixed with the ejaculated 

 semen. 



Male Elements of Generation. 



The ejaculated seminal fluid contains the male elements 

 of generation ; but it must be remembered that the complex 

 fluid known as the semen is composed of anatomical elements 



1 KRAUS, Preliminary Communication concerning the Function of the Pros- 

 tate Gland. Medical Times and Gazette, London, 1871, vol. i., p. 170. A sec- 

 ond and a more elaborate communication in the same volume of the Medical 

 Times and Gazette is devoted mainly to the pathology of the prostate. 



