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4. Prof. Valentin Haecker's Critical Review on Bastardization and Formation 



of the Sex Cells. 



By Thos. H. Montgomery, jr., University of Texas, Austin, Texas. 



eingeg. 20. April 1904. 



A very interesting review has recently appeared from the pen of 

 Prof.Haecker entitled »Bastardierung und Geschlechtszellenbildung«, 

 dealing with questions that are receiving much attention at the present 

 time. There are a few points in this review which need some emenda- 

 tion, due mainly to a misinterpretation or misunderstanding on the 

 part of Prof. Haecker of certain papers which he critizises. 



In the first place Prof. Haecker states my conclusion correctly 

 that the reduction in number of the chromosomes is effected previous 

 to the first maturation mitosis by a temporary conjugation of every 

 two chromosomes; my conclusion that this is a union in each case of 

 a paternal with a maternal chromosome; and my conclusion that such 

 chromosomes become separated from each other in the first maturation 

 division. But he is wrong in interpreting my position to be that as a 

 result of this division all the paternal chromosomes pass into one of 

 the daughter cells, and all the maternal into another. In this respect 

 his diagram III of Tafel 12 is erroneous. For in none of my papers 

 have I hinted at such a view; my paper (1901) rendered it very prob- 

 able that this could not be the case, and this is clear from the context, 

 though not stated in so many words, in my last contribution (1904) to 

 the subject. Indeed, my position is exactly that of Sutton (1902) who 

 argued that it would be purely a matter of chance as to which daughter 

 cell a particular chromosome would enter. The only differences be- 

 tween the results of Sutton and myself is as to the generation of the 

 reduction division, Sutton finding it to be second mitosis, and I to be 

 the first. Accordingly the diagrammatic series III and IV of Tafel 1 2 

 of Prof. Haecker' s review show a difference between the conclusions 

 of Sutton and myself which neither of us has maintained. 



Again: in foot-note 2 of page 199 of Prof Hacker's review we 

 read: »Wenn nun nach Montgomery in der Synapsis durch Contrac- 

 tion der verbindenden Liuinfasern eine Vereinigung je zweier univa- 

 lenter Elemente erfolgt, so ist nach meiner Ansicht dieser Modus der 

 Vierergruppenbildung nicht principiell verschieden von dem von Vom 

 Rath, mir und Rückert beschriebenen.« But there is nevertheless a 

 cardinal difference. Rückert (1894a), and Haecker and others after 

 him, concluded that there is a continuous chromatin spirem preceding 

 the first maturation mitosis, and that the apparent reduction in number 

 of the chromosomes is effected by this chromatin spirem segmenting 



