Introduction to cryptogamic botany / by M.J. Berkeley.

Date:
1857
Catalogue details

Licence: Public Domain Mark

Credit: Introduction to cryptogamic botany / by M.J. Berkeley. Source: Wellcome Collection.

Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.

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    a Threads from peridium of Batarrea phalloides, P. magnified. h A portion more highly magnified. c Threads from capillitum of Podaxon carcinomalis* that vascular tissue is but seldom found in the young plant before germination.-f- 5. A second character, distinctive of Cryptogams, consists in the fact that growth takes place in these plants from the tips of the threads of which they are composed and of their ramifications; or in other words, that the development is superficial. This, however, must be taken with much latitude, for when we come to particulars, the exceptions are very numerous. The rule, of course, applies to their vegetative * The threads of P. carcinomalis are rather allied to woody than to vascular tissue. They, in fact, resemble closely the elongated cells in the dark portion of the concentric rings of White Spruce Wood from the Arctic Eegions, as observed lately by Dr. Hooker. A similar structure exists, in what 1 take to be Scotch Fir, in a piece of drift wood, picked up at Lake Laura, on the western side of Wellington Channel, and kindly communicated to me by Capt. Inglefield. It is now a well-ascer- tained fact that a spiral structure exists in some varieties of cellular tissues, and perhaps in all. Cruger's papers in the Botanische Zeitung, 1854, and Agardh*^ on the spiral structure in the cells of Algae, may be consulted on this point. Hastig figures this spii'al pleurenchyme under Pinus pumilio. t A ready example to the contrary may be found in the fruit of the Horse Chesuut. °' De celluld vegetabili fibrillis ten uissimis contexts. Lundse 1852.