ACTION OF THE MALE. 587 



lie has distinctly seen to be penetrated by Spermatozoa. The act of Fecun- 

 dation is evidently analogous, therefore, in Animals, to the process which has 

 been described as taking place in the Flowering Plants. In many of the 

 lower tribes of Animals, the spermatic fluid effused by an individual of one 

 sex comes into direct contact with the ova previously deposited by the other ; 

 but in all the higher tribes, as in Man, the act of fecundation is performed 

 before, or shortly after the ova quit the ovarium. With these general views, 

 we shall now be prepared to consider the share which each sex has in the 

 Function of Reproduction. 



II. Action of the Male. 



734. The Spermatic fluid secreted by the Testes of the Male ( 700), differs 

 from all other secretions, in containing a large number of very minute bodies, 

 only discernible with a higher power of the Microscope ; and these, in ordi- 

 nary cases, remain in active motion for some time after they have quitted the 

 living body. The Human Spermatozoon (of which representations are given 

 in Plate I., Fig. 18), consists of a little oval flattened body from the l-600th to 

 the l-800th of a line in length, from which proceeds a long filiform tail, gradu- 

 ally tapering to the finest point, of l-50th or at most l-40th of a line in length. 

 The whole is perfectly transparent ; and nothing that can be termed structure 

 can be satisfactorily distinguished within it.* The movements are principally 

 executed by the tail, which has a kind of vibratile undulating motion. They 

 may continue for many hours after the emission of the fluid ; and they are not 

 checked by its admixture with other seminal secretions, such as the urine and 

 the prostatic fluid. Thus, in cases of nocturnal emission, the Spermatozoa 

 may not unfrequently be found actively moving through the urine in the morn- 

 ing ; and those contained in the seminal fluid collected from females that have 

 just copulated, are frequently found to live many days. Their presence may 

 be readily detected by a Microscope of sufficient power, even when they have 

 long ceased to move, and are broken into fragments; and the Physician' and 

 the Medical Jurist will frequently derive much assistance from an examination 

 of this kind. Thus, cases are of no uncommon occurrence, especially among 

 those who have been too much addicted to sexual indulgence, in which seminal 

 emissions take place unconsciously and frequently, and produce great general 

 derangement of the health ; and the true nature of the complaint is obscure, 

 until the fact has been detected by ocular examination. Again, in charges 

 of rape, in which evidence of actual emission is required, a microscopic exami- 

 nation of the stiffened spots left on the linen will seldom fail in obtaining proof, 

 if the act have been completed: in such cases, however, we must not expect 

 to meet with more than fragments of Spermatozoa?; but these are so unlike any 

 thing else, that little doubt need be entertained regarding them. It has been 

 proposed to employ the same test in juridical inquiries respecting doubtful 

 cases of death by suspension; seminal emissions being not unfrequent results 

 of this kind of violence : but there, are many obvious objections which should 

 prevent much confidence being placed in it.t 



735. The mode of Evolution of Spermatozoa, which has been recently dis- 

 covered by Wagner, is so different from the ordinary method of production 

 amongst Animalcules, as of itself to indicate that the former cannot be referred 



* It has been asserted that distinct oral and anal orifices, with appearances of internal 

 organs, have been seen in the Spermatozoa of certain Mammalia: but these observations 

 have not been confirmed; and they are not borne out by the attentive examination of the 

 larger Spermatozoa of other animals. 



| See the Author's Article "Asphyxia," in the Library of Practical Medicine, and the 

 authorities there referred to. 



