On the Extrusion of the Nuclear Substance 

 in Iris japonica, THUNB. 1} 



(Contributions from the Tokugawa Biological Institute, No. 3) 



By 

 Yosito Sinoto 



With 18 Text- Figures 



The phenomenon of extrusion of the nuclear substance in prophase 

 of pollen mother-cells into the cytoplasm of adjacent cells in Oenothera 

 Lamarckiana, O. odorata, Portulaca glandiflora and Iris japonica was 

 already mentioned briefly in my previous paper(22). The present 

 results of observations regarding the same phenomenon in Iris 

 japonica have been obtained by the study of the specimens prepared 

 for other purposes, so that the results may be far from being conclusive 

 in ascertaining the cause or meaning of this phenomenon. 



Young buds collected from the plants cultivated in a private 

 garden were fixed either in Flemming's stronger solution or in Bonin's 

 fluid ; the stains used were Heidenhain's iron-alum-haematoxylin with 

 a counter-stain of light green, and the methylene blue-fuchsin combin- 

 ation ; and the sections were cut 8 micra thick. 



OBSERVATIONS 



The fixation was generally bad for the study of meiotic phases. 

 The extrusion seems to be more frequently observed in the materials 

 fixed unsatisfactorily, not only in the case of the pollen mother-cells 

 but also in that of the ovular- and ovarian cells. It is interesting to 

 note that this phenomenon can often be found in the tapetal cells. 



]) A somewhat detailed account was published in Japanese in this magazine, 

 Yol. 35, No. 416, pp. (178)-(195), 1921. 



