Cytologie und Befruchtung. 131 



which appear to consist of chromatin together with linin. As 

 the reticulate phase passes away these are seen to be con- 

 nected by filaments that are often paired. Ultimately a spi- 

 reme is formed ; and the threads of which it is made up 

 become arranged, during synapsis, in the form of two parallel 

 strings. These then fuse. The fusion represents what other 

 authors have regarded as fission. Still later the thread thus 

 formed becomes less thigtly convoliited, and it then undergoes 

 longitudinal fission. The author describes and figures a large 

 variety of mature chromosomes which appear to be similar to 

 forms met with and already described by others for different 

 species of lilies. He considers that a second longitudinal fission 

 occLirs during metakinesis. A description of the homotype 

 mitosis is given, but the course followed is similar to that 

 already known in the case of many other plants. The paper 

 concludes with a theoretical discussion of the results, in which 

 the possibility that the first , apparently longitudinal, fission 

 really represents a Separation of the originally uniting threads, is 

 contemplated. The author indicates at some length the con- 

 nection between reduction and the facts of inheritance. 



J. B. Farmer (London). 



Maire, Rene. La mitose heterotypique chez les Ascomy- 

 cetes. (C. R. Acad. Sc. Paris. 3 avril 19ö5. T. CXL. 

 p. 950—952.) 



L'auteur ä signale anterieurement, chez le Galactlnia 

 siiccosa^ l'existence de protochromosomes, granulations chro- 

 matiques assez nombreuses qui se forment ä la prophase de 

 la premiere division et se reunissent, ä la metaphase, en quatre 

 elements de plaque äquatoriale. 



Les protochromosomes proviennent de la desintegration 

 du synapsis dont la formation precede la division consecutive 

 ä la caryogamie. Ils doivent etre interpretes comme corre- 

 spondant aux gamosomes de Strasburger. 



Les 4 elements de la plaque equatoriale presentent une 

 scission longitudinale manifeste; leurs deux moities se separent 

 ä la metaphase, puis subissent une nouvelle scission 

 longitudinale. Cette scission est le plus souvent complete, 

 de Sorte qu'ä l'anaphase on peut compter pres de chaque pole 

 8 elements chromatiques; mais d'autres fois eile se fait irreguliere- 

 ment, ce qui amene des differences de nombre entre les 

 elements des agglomerations polaires appartenant ä la meme 

 mitose. 



La premiere mitose de l'asque du Galactlnia est donc une 

 mitose heterotypique analogue ä celle de la plupart des 

 gonotocontes vegetaux. 



A la prophase de la seconde division, on voit reapparaitre 

 8 elements chromatiques, qui s'unissent 2 ä 2 en 4 elements de 

 plaque equatoriale ä la metaphase. On compte ä Fanaphase 



9* 



