194 ORGANISED FLUIDS. 



pound cells or spermatophori, the bright granules and the 

 seminal corpuscles probably represent stages in the deve- 

 lopment of the spermatophori. 



The several structures now named are all occasionally met 

 with in the ejaculated semen ; their occurrence in it is to be 

 regarded rather as accidental than as essential ; the sperma- 

 tophori belong to the testicle, the tubuli seminiferi of which 

 in many cases are almost filled by them. 



The spermatophori differ greatly from each other, both as 

 respects size and the number of secondary cells or nuclei 

 contained within them ; the smaller parent cells are about 

 TSo o f an mcn m diameter in man, and contain usually but 

 a single nucleus, while the larger ones attain the magni- 

 tude of QQ of an inch in breadth, and include not unfre- 

 quently as many as six or eight nuclei, or, more properly 

 speaking, secondary cells. Between the two extreme sizes 

 given, every gradation presents itself, and many spermatophori 

 contain but one, two, three, or four nuclei, which are the 

 numbers most frequently encountered. 



The secondary cells, like the primary or parent ones, are 

 globular, and those contained within the same parent cell 

 are usually of the same dimensions ; the centre of these cells 

 occasionally presents a bright spot. (See Plate X VI. fig. 1.) 



Not unfrequently certain large and perfectly transparent 

 cells are encountered ; these are in all probability the older 

 spermatophori, the contents of which have been discharged. 



It would appear, therefore, that the development and dis- 

 solution of the spermatophori are effected entirely within the 

 tubes of the testes. 



Cells, which Wagner has denominated seminal granules, 

 occur, as already remarked, mixed up with the undoubted 

 spermatophori ; these first are smaller, and do not contain 

 nuclei ; whether they are really distinct from the latter, it is 

 not easy to determine. If but one kind of cell occurs in the 

 testicle, then a double function must be assigned to it : thus in 

 the first place, the secretion of the liquor seminis must be 

 effected by it ; and in the second, the development of the 

 spermatozoa occurs within its cavity ; in which case the sper- 



