004 Journal of Applied Microscopy. 



Belajeff, W. Ueber die Centrosome in den Several months ago Belajeff expressed 

 spermatogenen Zellen. Bar. d. deutsch. the beUef that the deeply Staining 



bot. Gesell, 17: 100-2015, pi. IS. iSoo. i j- 1 -u j i i • ir ■ ^1 



^^ j> r J' y^ bodies described by himself m the 



spermatogenous cells of chara (1892) and in the Filicineae and Equisetaceai 

 (1895) represented the centrosome, and he claimed the same homology for the 

 conspicuous bodies in the spermatogenous cells of Cycas^ Giiigko, and Zaniia as 

 described by Hirase, Ikeno, and Webber. He also believes that Shaw is incor- 

 rect in not regarding the blepharoplasts of Onoclea and Marsilea as centrosomes. 

 The present paper is accompanied by a plate showing centrosomes in the 

 mother-cell and grandmother-cell of the spermatozoids of Gymuograme siilphurea , 

 Marsilea ?nacra, and M. Vestiia. These centrosomes would, of course, be 

 called blepharoplasts by Webber and Shaw. 



In conclusion, the question is asked why it is that v.'e do not find such 

 structures in vegetative cells of vascular Cryptogams and Phanerogams. The 

 answer suggested is that the dynamic center, which we call a centrosome, may 

 be present in all cells, but may not always contain a substance sensitive to stains 

 which would make it visible in preparations. c. j. c. 



Nemec, B. Zur Physiologie der Kern- und This paper contains a further exposi- 

 Zelltheilung. Bot. Centralbl. 77: 241-251, tion of the writer's views in regard to 

 ^^■' ^^' the differences between the mitoses of 



reproductive and vegetative cells. The general conclusion is that in relatively 

 free-lying cells of the sporogenous tissue the achromatic figure is multipolar and 

 often originates radially around the nucleus, while in cells of the vegetative 

 tissue the acromatic figure is bipolar from the beginning. In vegetative nuclei 

 the spindle makes its earliest appearance as a pair of hyaline caps at opposite 

 poles. No centrosomes were found with the vegetative nuclei even in those 

 plants like Equisetnm, Cycas, Zamia, and Giiigko, which in certain reproductive 

 cells have such conspicuous centrosomes. The list of plants examined includes 

 forty-four species, fairly representing Pteridophytes, Gymnosperms, and Angio- 

 sperms. c. j. c. 



Bruchmaan, H. Ueber die Prothallien und This work supplies a long felt need, for 



die Keimpflanzen mehrerer europiiischer few plant Structures have been less 

 Lycopodien. Gotha, pp. no, 7 pi., 1808. ., , , ^ i- i ^i ^1 



■^ ^ . i-r ^. / r . y accessible or less studied than the 



prothallia of Lycopodiiim. The prothallia of the European species are described 

 in considerable detail, and they present such marked characteristics that the 

 writer classifies them under five groups ; viz., (1) Type of L. clavatum and 

 L. annotinujH ; (2) Type of L. complanatum ; (8) Type of Z. selago ; (4) Type of 

 Z. phleginaria ; (5) Type of Z. ceniuiim, and Z. iiiiiiidation. 



In all the types the antheridia and the archegonia are borne upon the upper 

 surface of colorless prothallia, which, in some cases, become green if exposed to 

 the light. In Z. selago, and L. phlegmaria, there are paraphyses among the 

 antheridia and the archegonia. In Z. selago the prothallium produces adventi- 

 tious branches. 



The development of the embroyo of Z. clavatu?/i is described in great detail. 

 After fertilization the oospore becomes pear-shaped, and then divides into a 



