436 Cytologie und Befruchtung. 



ginnt dabei stets mit einem Uebermass auf Seiten des Plasmas. 

 Dies Missverhältnis wird jedes Mal nach einer Theilung dadurch 

 kleiner, dass die Plasmapartie auf die Hälfte verringert ist, 

 während der Kern wieder bis zur ursprünglichen Grösse heran- 

 wächst. 



7. Verf. glaubt, dass eine Regulation nur möglich ist, wenn 

 in jedem Kern mindestens f.'in Repräsentant der einzelnen 

 qualitativ von einander verschiedenen Chromosomen ver- 

 treten ist. Tischler (Heidelberg). 



Kraemer, Henry, FurtherObservations on theStructure 

 of the Starch Grain. (Botanical Gazette. Vol. XL. 

 1905. p. 305—310.) 



The peripheral layer of the starch grain is a distinct mem- 

 brane which is insoluble in water at ordinary temperatures, 

 while the inner portions are more or !ess soluble. When a 

 starch Solution which has been treated with iodine is heated to 

 60 — 80" C., a part of the freed iodine is volatilized. This ex- 

 plains the loss of color when such a Solution is heated and 

 the reappearance of a weaker color upon cooling. 



A method is given for the accurate staining of starch 

 grains. Charles J. Chamberlain (Chicago). 



Montoomery, Thos. H., The Terminology of aberrant 

 Chromosom es and their Behavior in certain He- 

 miptera. (Science XXIII. 1906. p. 36—38.) 



The recent discovery of chromosomes of different sizes in 

 the same nucleus in plants suggests that attention be called to 

 Prof. Montgomery's proposed terminology for aberrant 

 chromosomes in Hemiptera. The term chromosome is re- 

 tained where all chromosomes of a nucleus are alike; where 

 they are unlike, the name autosoma (or autosome) is applied 

 to those of the usual form, and allosoma (or allosome) to 

 the aberrant ones. When allosomes are unpaired in the sper- 

 matogonia they are called monosomes, and when paired, 

 diplosomes. Charles J. Chamberlain (Chicago). 



Schaffner, John H., The Nature of the Reduction Divi- 

 sion and related Phenomena. (Ohio Naturalist. Vol. V. 

 1905. p. 331—340.) 



In phylogeny the conjugation of nucleated cells introduced 

 a disturbance into the life cycle and a reduction division of 

 some kind became an inevitable accompanyment. The ways 

 and places at which a reduction division might theoretically 

 become established in the life cycle are discussed and presented 

 in diagrams. In the higher animals Prof. Schaffner believes 

 we have a condition similar to that found in Fucus. The signi- 

 ficance of a transverse division of the chromosomes, considered 

 with reference to Mendel's law, is illustrated and discussed. 



Charles J. Chamberlain (Chicago). 



