752 THOS. H. MONTGOMERY, JR. 
Flemming, Brauer and Boveri, maintained the occurrence of post- 
reduction, 7.e., reduction accomplished by the second maturation 
mitosis. It was Henking who first gave strong evidence that the 
first mitosis is reductional. Since 1898 I have tried to demonstrate 
for a number of objects (Hemiptera, Peripatus, Plethodon, 
Lycosa, Syrbula, Ascaris) it is the first mitosis that effectsthe 
actual reduction in the number of chromosomes, and not the 
second. This too is now fairly generally accepted, and Grégoire 
has taken the stand that it is actually proven for the greater 
number of the metaphyta and metazoa that have been studied. 
There are not many who longer hold that the second mitosis is 
reductional; the chief among them are McClung and his students, 
but others who have investigated the spermatogenesis of Orthop- 
tera (Gérard, Davis, Montgomery) have brought evidence to 
show that here too the first mitosis is reductional. Blackman 
agrees with the school of McClung, but then the chromosomes of 
the myriapods are admittedly unfavorable for the decision of this 
question. And it is not unimportant which one of the m tura- 
tion mitoses is reductional, for in some cases, as in certain par- 
thenogenetic eggs, there may be only one such mitosis, and it is 
a matter of great theoretical interest whether this is reductional 
or equational. 
But while it has been my good fortune to find so many issues 
for which I have contended now so generally maintained, there 
is one important question in which I would appear to have been 
mainly in the wrong, and it is my present observations that have 
convinced me of this. That is the question of the mode of 
conjugation of the chromosomes. Here there are two main 
opinions. The one, founded by von Winiwarter (00), is that of 
parallel conjugation of the chromosomes, known as parasyndesis 
(Hacker) or parasynapsis (Wilson). This view, which now 
enjoys much the greater support, goes to show that after the last 
spermatogonial mitosis the chromosomes become very delicate 
slender threads, the leptotene condition (von Winiwarter; lepto- 
nema, Grégoire); these then approximate themselves parallel 
into pairs making the zygotene condition (Grégoire; synapténe, 
