1905] CURRENT LITERATURE 383 
the opportunity to read the more extensive and scattered papers that deal with 
the subject—J. M. C. 
THE SECOND and concluding part of the second supplement (1896-1900) of 
the Kew Index has appeared. A notice of the first part appeared in Bor. 
GazeTre 39:68. 1905. The second part includes the letters L-Z, and also 
six pages of corrections and additions.—J. M. C. 
NOTES FOR STUDENTS. 
THE PROBLEM OF HEREDITY.—TuIs important contributions is similar in 
plan to the famous Cytologische Studien aus dem Bonner Institut which played 
such an important part during the centrosome controversies. The present work 
deals with the problem of chromatin reduction and with theoretical considera- 
tions connected with this problem. STRASBURGER® writes on typic and allotypic’ 
nuclear division, ALLEN on the behavior of the nuclear substance during synapsis 
in the pollen mother-cells of Lilium canadense, MIyAKE on the reduction division 
in the pollen mother-cells of certain monocotyledons, and OVERTON on the 
reduction division in the pollen mother-cells of certain dicotyledons. 
The four writers agree that the nuclear network consists of both linia and 
chromatin, and all but ALLEN describe a reducing or qualitative division of the 
chromatin during the first mitosis in the pollen mother-cell. 
STRASBURGER studied various pollen mother-cells and also the megaspore 
mother-cells, all of which are drawn from nuclei of the ovary walls and placenta 
of Galtonia candicans and Funkia Sieboldiana. His figures represent close series 
from the resting stage to telophase. Considerable variation in the number of 
mes was found in both forms. The bearing of this fact upon the 
theory of the individuality of the chromosomes is discussed, and the conclusion 
is reached that the number of chromosomes is fixed by heredity, but not within 
Such rigid limits as to exclude some variation in vegetative cells. The definite 
Prete 
* Index Kewensis plantarum Phanerogamarum: supplementum ae 
nomina et synonyma omnium generum et specicrum ab initio anni MDCCCXC 
oo oh aaalbee MDCCCC complectens. Ductu et consilio W. T- Thiselton- 
uratores. Leucocoryne— 
Oxford: Clarendon Press. 19°5- 
. STRASBURGER, E., ALLEN, C. E., MrvakE, K., and OVERTON, J- B., Histolo- 
BSche Beitrige zur Vererbungsfrage. Jahrb. Wiss. Bot. 42:1-153- Pls. I7- kal 
. * STRASBURGER, E., Typische und allotypische Kernteilung. Jahrb. Wiss. ae 
“I-70. pl, r- 1905. 
ic and homo- 
ic | AS ~ . 
sie The term allotypic is equivalent to the term ed wile 
R. STRASBURGER would restrict the term atypic to pathologic 
