1905] CURRENT LITERATURE 425 
a different title.' The most important change noted is the increased number 
of types discussed, and the presentation of these in a connected account. In 
harmony with this plan many unrelated details, especially concerning the vege- 
tative structure of the higher plants, are omitted. Though the number of forms 
discussed is increased from eleven to twenty-five, the size of the book is reduced, 
having three-fourths the number of pages in Plant Dissection. The types 
selected illustrate very well the probable steps in the evolution of plants, and the 
discussions are exceedingly clear and suggestive. It seems to the reviewer, how- 
ever, that the introduction of a heterogamous confervoid form might have strength- 
ened the presentation of the subject of heterogamy among the algae. So long 
as teachers have too large classes and too little time for purely inductive study 
in the laboratory, some form of written direction seems indispensable. Plant 
Morphology meets this demand in a most helpful way. A possible danger may 
lie in its excellence, in that weak teachers may depend upon it too fully and neglect 
the personal relation which should accompany laboratory study of this character. 
—R. B. WY1IE. 
NOTES FOR STUDENTS. 
Allen? has recently published in full the naar of ns ey of nuclear division 
in the pollen mother-cells of Lilim canadense, f 'y announce- 
ment which appeared last years This Lee is of especial interest in relation 
to the final paper of FARMER and Moore on the reduction divisions in animals 
and plants, since Allen reaches ensues different conclusions as to the 
events of synapsis and the preparations for the heterotypic mitosis. As FARMER 
and Moore also studied a species of Lilium (L. candidum), it seems hardly pos- 
sible that both accounts can be correct, so that the line separating the two schools 
is sharply drawn in these accounts of a similar form. One school is led by FARMER 
and Moore, and finds support in STRASBURGER’s recent paper Ueber reduk- 
tionsteilung (1904), and in the recent work of GREGORY on the leptosporangiate 
ferns, and of Writi1ams on Dictyota. With ALLEN are associated in the chief 
point of dispute (the formation of the bivalent chromosomes of the heterotypic 
mitosis) the botanists of the Carnoy Institute, GREGOIRE and BERGHs, and also 
OSENBERG. 
ALLEN’s account is chiefly remarkable for the detailed study of the events 
preceding and following synapsis, which are presented in greater detail than in 
any previous eins ie The nucleus of the young pollen mother-cell contains 
a network of e irregular masses, derived from the chromosomes of the pre- 
ceding eee in gs archesporium, and connected by fibers. As the nucleus 
increases in size, the chromatin knots become widely separated, and the nucleoli 
«CALDWELL, O. W., Handbook of Plant Morphology. 1r2mo. pp. vili+ 190. 
New York: Henry Holt & Co. 1904. 
2 ALLEN, C. E., Nuclear division in the pollen mother-cells of Lilium canadense. 
Annals of Botany 19:189-258. pls. 6-9. 1905. 
3 BOTANICAL GAZETTE 37: 464. 1894. 
