416 
J. BRONTE GATENBY. 
in regard to the origin of the apex, which is variously 
described as arising from the nuclear membrane, from the 
general cytoplasm, from the ‘ nebenkern/ and from the 
centrosome.” No author, I believe, has given the correct 
version of what really happens in the formation of the 
Lepidopterous spermatozoon, and the bodies confused 
generally are micromitosome, acrosome, and centrosome. 
In the glossary of his book Wilson gives the following 
interesting definitions : 
“ Mitosome (/li'itoq, a thread; crCofia, body), a body derived 
from spindle fibres of the secondary spermatocytes, giving 
rise, according to Platner, to the middle-piece and the tail- 
envelope of the spermatozoon. Equivalent to the Nebenkern 
of La Yalette St. George. (Platner, 1889.) 
“ Nebenkern (Paranucleus), a name originally applied by 
Biitschli (1871) to an extranuclear body in the spermatid ; 
afterwards shown by La Yalette St. George and Platner to 
arise from the spindle fibres of the secondary spermatocyte. 
Since applied to many forms of cytoplasmic bodies (yolk- 
nucleus, etc.) of the most diverse nature.” 
I have been unable to find any body in the spermatid 
formed from “ spindle fibres ” or “ yolk granules,” and I do 
not intend to use the term “nebenkern,” which has been,, 
and still is, used without discrimination for almost any 
granule or body in a cell. For example, Hegner ( 8 ) lately 
draws attention to the “ granules of Blochmann ” in the wasp 
and two ants, which have also been called “ nebenkerne,” 
quite regardless of whether or no they are of the same nature 
as the original “ nebenkern ” of Biitschli. 
In Text-fig. 1, I have drawn two figures (III and IY) to 
illustrate the nomenclature used in this paper. The bodies in 
the secondary spermatogonium have already been considered. 
In the spermatid we have the following bodies : 
(1) Two centrosomes without definite archoplasmic zone. 
(2) The micromitosome (identical with that body in the 
spermatogonium (M .) . 
(3) The macromitosome or middle part, formed from tlie 
