1899] STUDIES ON REDUCTION IN PLANTS 23 
the phenomena of plant life, extending even to nuclear phenom- 
ena, illustrated by the different types in fertilization, as shown 
by the investigations of Ikeno? in Cycas, Shaw’ in Onoclea, and 
Blackman* in Pinus sylvestris, as well as by Miss Ferguson™ in 
Pinus Strobus. 
Is it not well to inquire if some of the divergent and con- 
tradictory results regarding the behavior of the chromosomes 
obtained by different investigators, when dealing with different 
plants, are not due to the fact that we are dealing with different 
types in some cases? Are there not among plants different 
types of chromatin reduction? So that in one type there is 
represented a mass reduction, or quantitative reduction of the 
chromatin; in another type a pseudo-reduction, or numerical 
reduction only of the chromosomes; and in another type a 
qualitative reduction of the chromatin or reducing division of 
the chromosomes? Touching the hereditary or constitutional 
influences of fertilization, we recognize different types in plants, 
as shown by close- and cross-fertilization; and different types 
also in the mechanism for bringing about pollination. 
Some of the bewilderment which now surrounds certain 
phases of the study of the morphology of the nucleus will, I 
believe, disappear, if we recognize that there is such a thing as 
a reducing division or qualitative reduction in plants as repre- 
sented by such types as Trillium, Arisema, Adiantum, Pteris, 
Iris, etc.; that there are plants in which only a quantitative or 
mimerical reduction occurs, represented by such a type as Podo- 
phyllum ; and possibly that there is still another type, where 
° IKENO, S.—Untersuchungen iiber die Entwickelung der Geschlechtsorgane und 
—602 
den Vorgang der Befruchtung bei Cycas revoluta. Jahrb. f. wiss. Bot. 32 2557 
bl. 8-10. 1808. 
é © SHaw, W. R.—The Fertilization of Onoclea. Ann. Bot. 12 : 261-285. pi. 79. 
1898, ~ 
* BLACKMAN, V. H.—On the cytological features of fertilization and related 
pines in Pinus sylvestris L. Phil. Trans. Roy. Soc. B. 190: 395-426. pl. 72-74. 
** Miss Ferguson’s studies were carried on under my direction in the Bot. Lab. 
Cornell University, and a a paper, yet unpublished, was read before the Bot. Soc. Am. 
Aug. 1898, entitled “A preliminary note on fertilization in the white pine.” 
