782 



EMBRYOLOGY 



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." 



Glands of the Urethra. In front of the prostate, opening 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 throughout with cylindrical epithelium and secrete a 

 viscid, mucus-like liquid which forms a part of the ejaculated semen. 

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

 rarely, both are absent. Their uses probably are not very important. 



The glands of Littre, found throughout the urethra and most abun- 

 dant on its anterior surface, are simple racemose glands, extending 

 beneath the mucous membrane into the muscular structure, present- 

 ing here four or five acini. As these acini are surrounded with muscu- 

 lar fibres, it is easy to understand how their secretion may be pressed 

 out during erection of the penis. They are lined throughout with co- 

 lumnar or conoidal epithelium, and secrete a clear and somewhat viscid 

 mucus, which is mixed with the ejaculated semen. 



MALE ELEMENTS OF GENERATION 



The spermatozoids are the essential male elements of generation. 

 They are produced in the testicle, by a process analogous to that of the 

 development of other anatomical elements. The testicles can not be re- 

 garded strictly as glandular organs. They are analogous to the ovaries 

 and are the only organs in which spermatozoids can be developed, as the 

 ovaries are the only organs in which the ovum can be formed. If the 

 testicles are absent, the power of fecundation is lost, none of the secre- 

 tions of the accessory organs of generation being able to perform the 

 office of the true fecundating elements. 



In the healthy male, at the climax of a normal venereal orgasm, 11.6 

 to 92.6 grains (0.75 to 6 grams) of semen are ejaculated with consider- 

 able force from the urethra, by an involuntary muscular spasm. This 

 liquid requires about four days for its complete restoration. It is slightly 

 mucilaginous, grayish or whitish, streaked with lines more or less 

 opaque, and it evidently contains various kinds of mucus. It has a 

 faint and peculiar odor, sui generis, which is observed only in the 

 ejaculated secretion and not in any of its constituents examined 

 separately. It is a little heavier than water and does not mix with it or 

 dissolve. After ejaculation it becomes jelly-like and dries into a peculiar 

 hard mass, which may be softened by the application of appropriate 

 liquids. The liquid is not coagulated by heat and does not contain 



