Identifier: elementarybotan00atki (find matches)
Title: Elementary botany
Year: 1905 (1900s)
Authors: Atkinson, George Francis, 1854-1918
Subjects: Botany
Publisher: New York : Holt
Contributing Library: The Library of Congress
Digitizing Sponsor: The Library of Congress

View Book Page: Book Viewer
About This Book: Catalog Entry
View All Images: All Images From Book
Click here to view book online to see this illustration in context in a browseable online version of this book.

Text Appearing Before Image:
Fig. 493-Macrophytes in the upper zone of the photic region. Ascophyllum and Fucusat low tide, Hunters Island, New York City. (Photograph by M. A. Howe.) zonal distribution of plants. The different kinds of plants aredrawn into these zones by the varying amount of ground waterin the soil, or the varying depth of the water on the margin ofthe pond as one proceeds from the land towards the deeperwater. On the border lines or tension lines between the differentzones the plants are struggling to occupy here ground which issuitable for each adjacent individual formation. Other edaphicsocieties are those of marl ponds, alkaline areas, oases in deserts, PLANT SOCIETIES. 485
Text Appearing After Image:
M > <&O o CO . 3tJ- OO CO 486 RELATION TO ENVIRONMENT warm oases in arctic lands, the forested areas along river bottomsin prairie or plains regions, etc. 928. Aquatic plant societies—In general we might distinguishthree kinds, ist. Fresh-water -plant societies, with floating algaelike spirogyra, cedogonium, etc., the floating duck-meats, riccias;the plants of the lily type with roots and stems attached to thebottom and leaves floating on the surface, like the water-lilyand certain pondweeds, and finally the completely submergedones like certain pondweeds, the bassweed (Chara), etc.2d. Marine plant societies, which are made up mostly of thered and brown algae or seaweeds, though some green algaeand flowering plants also occur. 3d. The salt marshes wherethe water is brackish and there is usually a luxuriant growth ofmarsh-grasses. CHAPTER XLVII. CLASSIFICATION OF THE ANGIOSPERMS. Relation of Species, Genus, Family, Order, etc. 929. Species.—It is not

Note About Images