STRUCTURE OF THE PALM-STEM.

9

INTRODUCTION.

A minute anatomical examination of the Palms is ofespecial importance in regard to the anatomy and phy-siology of plants, because the characters of the Mono-cotyledons are most clearly exhibited in them, and theytherefore afford the most favorable means of acquiringsatisfactory ideas of the structure and growth of this greatclass of plants. As the earlier phytotomists had devotedbut little care to the examination of Palm-steins,* thesesuddenly acquired very great importance when Daubenton,in the examination of the Date-palm, believed that hefound the vascular bundles proceeding to the young leaves,becoming developed in the interior of the stem, surroundedby the vascular bundles running to the older leaves. Thisproposition, forming an epoch in the history of Phytotomy,first appeared in its full importance when Desfontainesfshowed that, not only in the Date-palm, but in Mono-cotyledons generally, the wood has the form of scatteredvascular bundles, and that the vascular bundles which runto the leaves come from the centre of the stem. This

* Vide Grew’s Examination of Calamus, Anat. of Plants, p. 104.t Mem. surl’Organisat. d. Monoe. (Mem. del’Institut National, t. i, 478).According to a brief notice published by Mirbel (Comptes Rendus, 12 Juin,1843), the first discovery belongs to Desfontaines, he having already, in his‘ Travels in Algiers, ’ expressed in a few words the idea which lies at thefoundation of his system.