270 J. B. GATENBY AND J. H. WOODGER 
middle-piece bead stains like the archoplasm of the spermatid, 
i.e. a deep pink or reddish. We consider, therefore, that the 
outgrowing bead figured by us in PI. 11, fig. 2, and Pl. 12, figs. 18 
and 14, probably consists of detached portions of both archo- 
plasm as well as Golgi apparatus elements. 
‘Tracing now the history of the bead after the stage at which 
it still adheres to the main Golgi apparatus, we next find that 
it has become separated from the latter in the manner shown 
in PI. 12, fig. 14. Ina large number of cases the bead has been 
observed lying in a position intermediate between the main 
Golgi apparatus and the nucleus, that is, near the letter m 
mer ly i ehee2: 
In the majority of cases the Golgi apparatus bead of the ripe 
sperm of Cavia les in the position shown in PI. 11, fig. 3, and less 
commonly in the position indicated in PI. 12, fig. 16. Reference 
to Text-fig. 1 shows that the middle-piece beads in other animal 
sperms vary a good deal in position. 
It seems probable that the small Gogh apparatus bead moves 
up from its position in PI. 11, fig. 2, or Pl. 12, fig. 14, to its defini- 
tive position near the head centrosome-complex (PI. 12, fig. 15), 
the bead becoming applied to the ‘skeleton’ of the middle- 
piece (mp in Pl. 12, fig. 14) at a time when the mitochondrial 
granules (m) are themselves becoming grouped around the 
skeleton. 
a. Pans ho tera iire. 
Meves (20), in his classical paper on the spermatogenesis, 
has given a detailed review of previous work on Cavia. ‘To 
this the reader may be referred. More recently Papanicolaou 
and Stockard (26) have gone over the same ground, and also 
given a comprehensive review of the results of previous 
observers. The work of Papanicolaou and Stockard is chiefly 
concerned with the fate of the archoplasm (their ‘ idiosome ’) 
and its contents based on a study of material stained with 
a new methylene-blue-acid fuchsin combination after Zenker’s 
fixation. The following is a brief résumé of their account, 
using their new and elaborate terminology. 
