Introduction. Polypetalae. Gamopetalae (Google eBook)

Front Cover
Clarendon Press, 1908 - Botany
0 Reviews
  

What people are saying - Write a review

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

Common terms and phrases

Popular passages

Page x - I would like to express my warmest thanks to all those who have assisted me in so many ways.
Page 20 - Mem. de la Soc. des sc. phys. et nat. de Bordeaux, se'r.
Page 8 - Experience shows that one species reacts in one way, other species in a different way, under the action of the same stimulus, but that the reaction is often of the same kind in plants belonging to the same phylum. Thus one species protects itself against desiccation solely by means of mucilage receptacles, another by the development of hypodermal aqueous tissue, a third by enlargement of epidermal cells, and others by two or more of these features.
Page 12 - ... feature. Anatomical characters sometimes lend support to the results obtained by the use of external morphology, ie when they coincide with the external characters. Frequently, however, they disclose new points of view regarding affinities and thus serve to improve and complete the Natural System. Anatomical characters are often preferable for the determination and delimitation of a systematic group, since they are more precise than external morphological characters and possess the further advantage,...
Page 309 - Constant anatomical characters are almost wanting in this Order." Also, ". . . . cork formation is superficial in Pruneae and Pomeae. " He further states, "With regard to the structure of the root, it may be mentioned that in many genera the layer of cells situated immediately outside the endodermis is provided with ridge-like thickenings on the radial and transverse walls (Van Tieghem's 'reseau sus-endodermique'). These are found in Prunus, Pyrus and Cydonia.
Page 120 - Secretory canals are present in the pith and in the primary cortex of the axis in almost all the members of the Order ; at the same time, they sometimes also occur in the primary and secondary bast, or in the secondary bast only. In the leaf the secretory canals either follow the vascular bundles in the veins or run independently of the vascular bundles in the mesophyll ; in the latter case they are sometimes (in the genus Calophyllum, see Fig.
Page 425 - When the first ring of concentric vascular bundles is complete, a second ring consisting of groups of vessels is developed internally ; these are entirely separate from the bundles, and from them a second ring of concentric strands originates; still further to the interior new groups of vessels arise, and from these concentric bundles are again formed. As a consequence of this successive mode of development the bundles of the outermost ring are most strongly differentiated.
Page 266 - ... of the bast and also accompanying the sclerenchyma of the veins. They are, strictly speaking, not solitary, but hemitropic crystals, consisting of two or more individual crystals arranged with their longitudinal axes in approximately the same direction, and consequently in certain positions they appear bent at one or more places.
Page 463 - the primary lactiferous system of the root is however connected with the primary system of the stem, for at a certain level both systems are found to be present in a transverse section and united with one another by anastomoses.
Page 585 - Especially characteristic are the branched multicellular candelabra hairs, which consist of an upright, uniseriate main axis, from which whorls of from 2 to 8 ray-cells arise at certain points, the individual cells being from 0.150 to 0.400 mm. in length and contain not infrequently 1 or more airbubbles ; glandular hairs 2-celled, consisting of a stalk, from 0.030 to 0.065 in length and having a nearly spheroidal secreting cell at the summit ; epidermal...

Bibliographic information