and Laboratory Methods. '2529 



CURRENT BOTANICAL LITERATURE. 



CHARLES J. CHAMBERLAIN, University of Chicago. 



Books for Review and Separates of Papers on Botanical Subjects should be Sent to Charles J. 

 Chamberlain, University of Chicago, Chicago, 111. 



Miyake, K. On the development of the sexual The pollen grain at the time of shed- 

 organs and fertilization in Picea excelsa. ■.. i . ,i i i • ,r 



Annals of Botany, 17: 351-372, pis. 16-17, ding— about the second week in May— 



i9°3- contains two disorganized prothallial 



cells, a stalk cell, body cell, and tube cell. The tube begins to form a few days 

 after pollination and the body cell at once passes into it and divides, giving rise 

 to the two male nuclei. At this division the beginning of a cell plate appears 

 at the equator of the spindle, but it soon disappears and no wall is formed ; 

 consequently the two male nuclei lie free in a common mass of cytoplasm and 

 there is no formation of two cells as described by Strasburger, Belajeff, Dixon, 

 and Coulter. The pollen tube does not branch. 



The development of the archegonium is very much as in Pinus. In the neck 

 of the archegonium there are 4 to 8 rows of cells with 2 to 4 cells in a row. 

 There are usually four archegonia in each ovule, but the number varies from two 

 to seven. During the growth of the egg no passage of nuclear material from 

 the jacket cells into the egg could be detected. The ventral canal cell is formed 

 about a week before fertilization, which, in the neighborhood of Ithaca, occurs 

 about the middle of June. No walls are formed in the proembryo until it has 

 reached the eight-celled stage. Strasburger describes walls at the four-celled 

 stage and other writers have described walls at the four-celled stage in Pinus. 



The antheridial cell of Strasburger (third prothallial cell of Belajeff) is called 

 the central cell by Dr. Miyake, who regards it as the equivalent of the central 

 cell of Pteridophytes. The " body cell " of Strasburger is called the generative 

 cell. Strasburger refers to the two male cells as "generative cells." The ter- 

 minology is confusing, and we are not sure that the present writer has been 

 entirely consistent. c. j. c. 



Zacharias, E. Ueber die "achromatischen " This paper deals with the contents of 



Bestandtheile des Zellkerns Ber. d. deutsch. ^^e nucleus, exclusive of the nucleolus 

 l)ot. desell.ZO: 290-320, pi. 16, 1902. '_ 



and nuclein -containing structures. 



Pollen mother cells of Larix, Iris, Hemerocallis and other forms, were investi- 

 gated. Material was examined in the living condition and also after treatment 

 with various reagents, but sections do not seem to have been used. In dealing 

 with nuclei in division after the nuclear membrane has broken down, the special 

 term, nuclear cavity {Kern?-auni), is used, because the sphere of influence of the 

 nucleus may not be the same as when the nuclear membrane is intact. The 

 writer does not agree with Nemec's statement that the spindle fibers consist of 

 plastin, but believes that plastin may be present in some cases while in others it 

 may be lacking. 



In the living cell during nuclear division the nuclear cavity, with the excep- 



