Plant World: Its Past, Present & Future; an Introd. to the Study of Botany

Front Cover
Whittaker, 1891 - 212 pages
 

What people are saying - Write a review

We haven't found any reviews in the usual places.

Other editions - View all

Common terms and phrases

Popular passages

Page 111 - Strychnos nuxsomica, are valuable medicines, depending on the strychnine they contain, which acts as a powerful excitant of the spinal cord and nerves ; thus the most effective protective arrangements evolved by plants can be turned to account, and consequently lead to the destruction of the individuals they were designed to protect. Our common arum (Arum maculatum), popularly known as 'Lords and Ladies...
Page 110 - U. urens), in these cases the stinging hairs are mixed on the leaves and stem with ordinary rigid hairs, of which they are higher developments, distinguished by the lower or basal swollen portion of the hair containing an irritating liquid that is ejected when the tip of the hair is broken off. Bitter taste, often accompanied by a strong scent, as in wormwood (Artemisia vulgaris), chamomile (Anthemis ndbilis} , and the leaves and fruit of the walnut (Juglans regia).
Page 110 - Poisonous alkaloids, as in the species of Strychnos, which contain two very poisonous alkaloids, strychnine and brucine, in the root and the seeds ; decoctions of species of Strychnos are used by the Javanese and the natives of South America to poison their arrows. Some of the species, as Strychnos...
Page 111 - Ladies,- hns an intensely acrid substance present in the leaves, which effectually protects it from the attacks of mammals and caterpillars, but not from the attacks of parasitic fungi, which appear to be indifferent to all protective contrivances exhibited by plants, nearly every plant supporting one or more of these minute pests, the effects of which will be realized by mentioning the potato disease, ' rust ' and ' smut ' in the various cereals, and the hop disease, all due to parasitic fungi.
Page 110 - ... thus prevent the nibblings of animals, or in more advanced species, curved, thus enabling the weak stem to climb and carry its leaves out of harm's way. Spines, that are sharp-pointed abortive branches, serving the same purpose as prickles, as in the common sloe or blackthorn (Prunus spinosa). Rigid hairs on leaves and stem, as in the borage (Borago officinalis) , and comfrey (Symphytum officinale). Stinging hairs, as in the common nettles (Urtica dioica, and U. urens), in these cases the stinging...
Page 174 - ... the latest comers in a majestic procession which has been marching through an unknown series of ages. At the head of this procession we ourselves stand, heirs of all the progress of the past and moving forward into the future wherein progress towards something higher and nobler must still be for us, as it has been for all creation, the guiding law.
Page 61 - ... arranged in the following order red, orange, yellow, green, blue, indigo, violet.
Page 54 - ... membranes, this is not the only meaning given it. The definition given by Brubaker, and the one by Washburn, are evidently made in the attempt to give a more definite meaning to the term. The so-called law of osmotic movements of liquids as stated by Clements11, Ganong12, Peabody13, and others, is as follows: "When two liquids of different densities are separated by a membrane, they pass through the membrane and mingle and the flow is always from the less dense to the more dense.
Page 130 - ... indispensable, yet all these elaborate arrangements have not prevented the violets from evolving something even more effectual and at the same time more economical in connection with fertilization, and in reality the oldfashioned...
Page 12 - The multicellular forms may consist of a single row of cells placed end to end, as in the moniliform hairs of Tradescantia, Fig.

Bibliographic information