and Laboratory Methods. 1255 



CURRENT BOTANICAL LITERATURE. 



Charles J. Chamberlain. 



Books for review and separates of papers on botanical subjects should be sent to 



Charles J. Chamberlain, University of Chicago, 



Chicago, 111. 



REVIEWS. 



Juel, H. 0. Vergleichende Unterschungeniiber A preliminary note announcing the dis- 



typische und parthenogenetische Fortpflan- covery of parthenogenesis in Antenna- 



zung bei der Gattung Antennana. Kongl. ■' '^ " _ 



Svenska Ventenskaps-Akademiens Hand- >'ia alpiiia appeared in the Botanisches 



lingar. U'. 3-56, pis. 1-6,1900. Centralblatt about two years ago. It 



was also noted at that time that Antenuaria dioica presented a very different 

 developmental history. The author's subsequent work upon these two species 

 is described in great detail in the present paper. 



In the nucellus of Antcjina?'ia dioica the sequence presents nothing excep- 

 tional, the mother cell of the megaspore producing four potential megaspores, 

 one of which continues to develop at the expense of the other three and becomes 

 the embryo-sac, just as in other Compositse. The antipodal cells continue to 

 divide and form a tissue, nineteen cells appearing in one section in one of the 

 author's figures. Fertilization of the ^gg takes place in the usual manner, but 

 no double fertilization could be detected. At the first division of the nucleus of 

 the megaspore mother cell, a reduction in the number of chromosomes takes 

 place. The production of a row of four potential megaspores is regarded as a 

 true tetrad formation. 



In Antennaria alpina the mother cell of the megaspore becomes the embryo- 

 sac directly, just as in Li/iion, without giving rise to a row of four potential mega- 

 spores, but, unlike Liliiim and other plants, it shows no reduction in the number 

 of chromosomes. Prof. Juel's previous statement that the embryos develop with- 

 out fertilization and that there is no fusion of polar nuclei, is repeated with more 

 detailed evidence. 



Only one plate is from camera lucida drawings, the other five being taken 

 from photographs and photo-micrographs. The latter were made with a 2 mm. 

 oil immersion objective. The exposures were about two minutes long and no 

 ray filters were used. While the figures show the stages fairly well, they also 

 show the limitations of photo-micrography in its present stage of development. 



c. J. c. 



Smith, R. Wilson. The Achromatic Spindle in The object of this work was tO extend 



Z.^Zll'^tAt.t^r^^^ '"""' ""' '"'^^'-'^ knowledge of the cytology 



of the vascular cryptogams. In the 

 spore mother cell of Ostnunda rega/is, Smith finds that the spindle originates out 

 of a granular zone of cytoplasmic material which accumulates about the nucleus. 

 The granules of this material arrange themselves into short rows concentric with 

 the nuclear membrane. These rows of granules become massed at opposite sides 

 of the nucleus and eventually become the cones of a bipolar spindle. The spin- 



