716 The American Naturalist. [August, 
Mr. T. C. Palmer describes (Proc. Acad. Nat. Sci., Philadelphia, 
March, 1897), a method of demonstrating the absorption of carbon 
dioxide, and the generation of oxygen, by diatoms, by the use of inverted 
test-tubes filled with water tinged with hematoxylin. On the addition 
of carbon dioxide the rosy tint turns yellow, and, as the diatoms absorb 
the acid, the rosy tint reappears. 
The third of the “ Teachers’ Leaflets on Nature Study,” issued by 
Professor Bailey, is entitled “ Four Apple Twigs.” Like its predeces- 
sors, it is certain to be very helpful to both teachers and students. 
Professor M. A. Brannon’s paper on the “Structure and Development 
of Grinnellia americana,” in the March number of the Annals of 
Botany, brings out a number of interesting facts about this beautiful 
American red seaweed. He found this species to be particularly well 
adapted to the study of the various phenomena of reproduction. The 
plant, when cut into small pieces, reproduces vegetatively by prolifera- 
tion. Carpospores and tetraspores germinate readily under favorable 
conditions which are easily controlled. The antherozoids (which are 
non-motile) are formed by abstriction. The trichogynes are often 
branched, sometimes as many as five growing from a cystocary. The 
pericarp is only two or three layers thick. 
Mr. F. V. Coville publishes some interesting notes on the plants used 
by the Klamath Indians of Oregon (Contrib. U. 8. Natl. Herb., V, 
No. 2) as one of the results of a botanical survey of the plains of south- 
eastern Oregon in 1896. The plants considered range from lichens 
(Alectoria fremontii and Evernia vulpina) to grasses, lilies, knotweeds, 
roseworts, umbelworts, and composites. These plants are used for food, 
dyes, clothing, bows, arrows, baskets, buckets, medicines, etc. 
Bulletin 9 of the Minnesota Botanical Studies maintains the high 
standard of this unique state publication. It contains papers on the — 
Lichens of Minneapolis (Fink), the North American Hyphomycetee 
(Pound and Clements), Mosses at High Altitudes (Holzinger), Dorsi- 
ventral Leaves (Day), the Genus Coscinodon in Minnesota (Holzinger), 
the Ferns and Flowering Plants of the Hawaiian Islands (Heller), 
Symbiosis (Schneider), the Distribution of Woody Plants at Lake of 
the Woods (MacMillan), the Alkaloids of Veratrum (Frankforter). 
J. Webber’s paper on the Water Hyacinth (Piaropus crassipes 
(Mart.) Britton) in Bulletin 18, of the Division of Botany of the U. S, 
Department of Agriculture, describes the rapid spread in Florida 
rivers of a very pretty plant hitherto used for ornamental purposes, 
until it has now become an intolerable nuisance. It often seriously 
impedes, and, in fact, sometimes actually stops the progress of steam- 
boats. The problem of its eradication is a very difficult one. 
