454 
J. BRONTE GATENBY. 
are distributed whole to one or the other daughter cell. I 
have already shown that abnormalities may occur, and that 
one cell may get more than its share of the mitochondrial 
mass, but for Meves's conclusion that the mitochondria carry 
the hereditary characters of the cytoplasm we need evidence 
and not supposition. The view is interesting and worthy of 
the most careful attention. 
Meves (10) claims in Ascaris that the mitochondria of the 
female fuse with those of the male, a view previously urged 
by Zoja (11), but, as far as I know up to the present time, 
nothing similar has been described elsewhere. With regard 
to the question of the origin of the mitochondria in the young 
germ-cells, I think that in moths they are already present 
from the segregation of these cells, being passed on perma- 
nently from parent to offspring, but in other forms there is 
still the question as to the origin of the mitochondrial 
granules from the nucleus. 
We now come to a review of Meves’s “apyrene” and 
“ eupyrene ” spermatozoa. Meves fully believed that the 
“apyrene” sperms were functional, though he only had his* 
theory to go upon. Doncaster (5) is sceptical of the truth of 
Meves ; s conclusion that the spermatozoa of the two kinds may 
affect sex. The “ apyrene spermien ” I believe to be degene- 
rate, and of no importance in fertilisation ; those who have 
studied germ-cells even cursorily have noted that degeneration 
takes place not at one stage but at every step. Meves’s 
“ apyrene ” sperms, I believe, are examples of flagging 
energy in cells, and are due to some cause unknown to us. 
I have taken testes full of “ apyrene spermien ” and stained 
fresh in osmic acid or scarlet red, and have found the walls 
of the testis to be full of fat cells and globules. The 
degeneration observed cannot be due either to a want of 
nourishment or a diversion of such nourishment to other 
sources. Whole nests of spermatogonia and oogonia in many 
animals are to be found in process of degeneration. In some 
way or other the “apyrene” chromosomes lack the energy,, 
whatever that may be, to coalesce to form the nucleus. 
