752 



Grnrsuie 



i 



E 



^ 







I'K., 1:M.'i KliriMiii 1. 1,-1 I, M~ of mammalian >i>riiii. A.V> >tagcs m tlic lorniation of the 



Lead cap of the humau sperm. B, late spermatids of the eat (i) and guinea pig {2) in 

 roughly longitudinal section; note approximation of axial filament to centriole. C, principal 

 piece of guinea pig sperm tail ; note that each peripheral doublet appears as one tubular and 

 one solid element: 7 outermost fibers are present at this level (see Fig. 13.175). D, terminal 

 region of human sperm tail; the doublets appear as hollow cylinders. E, midpiece of human 

 sperm ; the electron-dense outermost array of filaments is surrounded by many mitochondrial 

 bodies. {A and B from D. W. Fawcett, Internat. Rev. Cytol., 7, 195-234. 1958; C, courtesy 

 of D. W. Fawcett; D and E from A. Anberg, Acta ob.st. et gvnec. scandinav., Sup])l. 2, 36, 

 1-133, 1957.) 



