322 BOTANICAL GAZETTE [May 
must take cognizance of the extensive literature on this subject 
concerning both plants and animals, and also the rapidly develop- 
ing field of experimental cytology, in making his interpretations 
and drawing his conclusions. Nowhere is the fundamental unity 
of all organic matter better exemplified than in the study of these 
nuclear processes. 
It is not my purpose to trace the history of the many changes 
of opinion regarding the method of chromosome reduction which 
have occurred as our knowledge of this process has developed. 
I wish merely to consider certain of the current views, and to 
express my own point of view, which has resulted from careful 
studies of reduction in various races and species of Oenothera, and 
the comparison with many other forms,? both from preparations 
and from the literature, as well as from a consideration of the many 
important data from experimental cytology, and the crossing of 
forms whose chromosomes differ in number or in morphology. 
This point of view, therefore, results from the consideration of 
data bearing on the chromosome question from every angle, 50 
that it would be useless to attempt a citation of all the facts upom 
which it is based. Nor shall I attempt in this paper to formulate 
a complete hypothesis of chromosome behavior, nor of the proces 
hereditary réle of the chromosomes. My special endeavor will 
be to show how the chief divergent current opinions regarding 
meiosis may be unified and harmonized. This will of course ae 
involve incidentally the expression of certain views regarding the 
nature of the chromosomes themselves. I regard it as the duty 
of every discoverer of new facts to bring them into relation, and 
if possible into harmony, with the other authenticated facts in the 
same field. The present paper is an attempt to fulfil this functon 
with regard to my own studies on chromosome reduction. To f 
this in the present state of our knowledge of this process requires : 
that the subject be approached from a broader viewpoint, if the 
: . f 
*I am greatly indebted to Professor Grécorre for kindly giving me the wae 
his laboratory facilities during my stay at Louvain, and for many animated and ctl 
cal discussions of current cytological problems. I am also indebted to Professot 
STRASBURGER for the courtesies of his laboratory, and for the privilege of examining 
a large number of cytological preparations. I alone, however, am responsible for the 
views here expressed. 
