206 KANSAS UNIVERSITY SCIENCE BULLETIN. 



merits Montgomery does not say. He, however, insists that he 

 has always known that the fusion by pairs takes place. How 

 this was to be brought about under his previous assumption 

 that one of the fourteen spermatogonial chromosomes became 

 removed from participation in the usual processes of the cell to 

 form a "chromatin nucleolus," he fails to state. Until the con- 

 fusion is cleared up by corroborative evidence on one side or 

 the other, a most important' part of Montgomery's work must 

 still be regarded as uncertain. 



Despite his recognition of the fusion of the chromosomes in 

 the synapsis as the essential feature of this stage, Montgomery 

 is insistent upon the concentration of the chromatin as its dis- 

 tinguishing characteristic. Regarding this he says : " McClung 

 considers the appearance of the synapsis stage as artefacts. It 

 is hardly necessary to reply to this criticism, since in all 3Ietazoa 

 where the spermatogenesis has been carefully examined, with 

 the exception of certain Amphibia, the dense massing of the 

 chromosomes (?) in the synapsis stage has been shown to be a 

 perfectly normal phenomenon." 



Concerning two points in this statement I wish to take excep- 

 tion. First, as was suggested in my previous paper (17), the 

 term synapsis is usually applied to a condition of the prophase 

 in which the apparently unsegmented spireme exists. It must 

 be remembered that most investigators consider that the reduc- 

 tion of the chromosomal number takes place by the segmenta- 

 tion of a spireme into half the usual number of segments. In 

 the second place, I must resent the implication that the work 

 done in this laboratory is not "carefully" conducted. Many 

 "Metazoa" have been examined "carefully," and in none has 

 the "synapsis" occurred when the material was well fixed and 

 prepared. It has, moreover, been found possible to produce 

 the appearance at will. One case of this kind is sufficient to 

 raise the presumption that it may not be normal even when 

 constantly found in certain preparations. I have not, however, 

 absolutely denied the possibility of such an occurrence, because 

 it is conceivable that from the telophase of the preceding divi- 

 sion the massing of the chromosomes may persist during their 

 elongation. My contention is that the appearance is not a con- 

 stant or necessary condition in "all the Metazoa," and this I 

 have proven. 



