884 OF GENERATION ACTION OF THE MALE. 



stated by Letzerich 1 to pierce the membrana propria of the tubuli seminiferi, 

 and end in a more or less irregular pyramidal mass of protoplasm, in which 

 lie clear elliptic nuclei. The ends of the fibres, therefore, lie in close rela- 

 tion to the outer layer of secreting cells. 



731. The fluid secreted by the Testis is invariably alkaline in Man, and 

 is mingled, during or previously to its emission, with fluid secreted by the 

 Vesicular Seminales, the Prostate, Cowper's glands, etc. ; and it cannot, there- 

 fore, be obtained pure, but by drawing it from the testicle itself. No accu- 

 rate analysis of it has been made in the human subject ; but Kolliker 2 has 

 made the following analysis of it in the Bull and Stallion : 



Bull. Stallion. 



Water, 820.60 819.40 



Solid residue, 179.40 180.60 



Spermatin and Extractive, . . . 153 164 49 



Fat, 21 6 



Salts, 26.37 16.11 



And Frerichs, 3 on examining the contents of the Testes of a Rabbit, a 

 Cock, and a Carp, found pure Semen to be a milky fluid of a mucous con- 

 sistence, and neutral or slightly alkaline reaction. The imperfectly devel- 

 oped Spermatozoa are composed of an albuminous substance, the quantity 

 of which diminishes with their progress towards maturation ; so that the 

 perfectly developed semen contains no albuminous compound. On the other 

 hand, the principal component substance of the mature Spermatozoa is the 

 same with that which is the chief constituent of the Epithelia and of the 

 Horny tissues generally namely, the " binoxide of protein " of Mulder. 

 Besides this, the spermatozoa contain about 4 per cent, of a butter-like; fat, 

 with some phosphorus in an unoxidized state (probably combined with the 

 fat as in the phosphorized fats of the blood-corpuscles and of nervous matter), 

 and about 5 per cent, of phosphate of lime. The spermatozoa evince little 

 tendency to decomposition-, and offer considerable resistance to the action of 

 sulphuric, nitric, hydrochloric, and acetic acids, and to caustic alkalies at 

 ordinary temperatures. The fluid portion of the secretion is a thin solution 

 of mucus, which, in addition to the animal matter, contains chloride of 

 sodium, and small quantities of alkaline sulphates and phosphates. When 

 allowed to evaporate spontaneously, crystals appear, which are composed 

 either of ammoniaco-magnesiau phosphate, or, as Bottcher thinks, of albu- 

 men. The peculiar odor which the Semen possesses does not appear to belong 

 to the proper spermatic fluid ; but is probably derived from one or other of 

 the secretions with which it is mingled. The product of the secretion of each 

 Testis is conveyed away by a single vas deferens (9), which is a cylindrical 

 canal, having, within its fibrous wall, a layer of non-striated muscular fibre, 

 and being lined by a proper mucous membrane. The vas deferens, ascending 

 into the abdominal cavity as a part of the spermatic cord, reaches the fundus 

 of the bladder; and there it conies into proximity with the Vesicitln Xcmi- 

 nttli* of its own side, with whose duct it unites to form the cjncnliiorij ilnct 

 which terminates on the venimontanum of the urethra. It has been com- 

 monly supposed that the vesiculcv semhinli^ stand to the vasa deferentia in the 

 same light that the gall-bladder stands to the hepatic duct, namely, as a recep- 

 tacle into which the seminal fluid may regurgitate, and within which it may 

 accumulate; but (as Hunter was the first to maintain) this is not the case, 

 since the fluid that is found in them is not semen, and but rarely contains 

 even a small admixture of seminal fluid. 4 Moreover, these organs are not 



i Vircliow's Aivliiv, March, 1868. 2 v. Oorup-Besanez, 1862, Phys. Chem., p. 424. 



;1 Art. Si'incn, in Cyclop, of Anat. and Physiol , vol. iv, p. 506. 



4 See Art. Vesicula3 Seminales, in Cyclop, of Anat. and Physiol., vol. iv, p. 1431. 



