Bonin} OLEERATURE. 
BOOK REVIEWS. 
American fossil cycads.* 
SINCE 1898 Dr. WIELAND has been investigating the wonderful American 
display of fossil cycadean forms, usually referred to now as the Bennettitales. 
The investigation has demanded an unusual amount of patience and hard work 
in making the necessary collections and sections. The student of living plants 
has no adequate conception of the labor involved in obtaining valuable results 
from sectioning fossil material. The result of all this work now appears m . 
ulky memoir published by the Carnegie Institution. It is a veritable mine of 
information in reference to Bennettitales, a mine that will be worked by botan- 
ists for a long time to come. To present the results here would be to write 
another book. They are not essentially new, but they are so much more com- 
plete and more finely illustrated than ever before that the student of gymno- 
sperms must always consult this volume. ‘ 
The contents may be outlined by giving the chapter headings as follows: 
discoveries and collections, preservation and external characters, on the methods 
of section cutting, trunk structure, foliage, ovulate cones, bisporangiate - 
young fructifications, existing and fossil cycads* compared, fern ancestry 4m 
angiosperm analogies. 
The author is to be congratulated upon the amount of good work t 
accomplished and upon the fine and permanent form in which it has ap 
Morphologists can now lay hold of this material as they never could before, 
organize it for general use.—J. M. C. ” 
MINOR NOTICES. 
Reproduction.—Under the title “multiplication and sexuality in p 
KtstEr’ has published some expanded lectures which were given 1D anu 
and February of this year and constituted ‘‘an advance course for east 
Vegetative multiplication is first considered in the higher plants, then ™ pi 
lower. Sexual reproduction is treated historically, and then taken uP from ' =m 
standpoint of its evolution, the lower forms being treated first. The gene 
ne- 
problems discussed are: sexual affinity, hybridization, polyspermy, eee 
and 
hat he has 
and 
” 
ants, 
sis, apogamy, apospory, and distribution of sexes. ‘The book closes W? h 
on theories of reproduction and sexuality. It is a convenient, compact, 
reliable compendium of the subject—CHartEs J. CHAMBERLAIN. 
t WIELAND, G. R., American fossil cycads. pp. 296. pls. 50- figs. 138. Oe 
Institution. 1906. — 
2 Kister, Ernst, Vermehrung und Sexualitit bei den Pflanzen. 8vo. 
figs. 38. Leipzig: B. C. Teubner. 1906. 
222 
p. vit 12% 
