J 08 



NATURAL HISTORY OF PLANTS. 



remarked by Lindley' for possessing areolate punctations like those 

 of the Conifers, or ratlier of Araucarid. This assertion has since been 

 confirmed by several observers." Further, these plants have no 

 other vessels than those few we find outside the pith in a branch one 

 year old, of which only a small number are true trachea), with a thread 

 that can be unrolled. The other woody layers, produced afterwards 

 at different periods of vegetation, consist only of fibres with areolate 

 dots. Trocliodendron, whose place among Maf/noIiacecE had been con- 

 sidered doubtful, presents the same peculiarity.^ The MagnoliecB 

 and lUiviuni, on the contrary, have vessels in concentric zones, 

 alternating with those of w^oody fibres, and in this respect return to 

 the common plan of structure in Dicotyledons ; so does the genus 

 Hnpfelea* very closely allied to Trocliodendron. Hence there is no 

 absolute character common to the whole order to be found in the 

 relative distribution of the vessels and the fibres. But we have 

 shown in a memoir which we reproduce below,^ that the stems of 

 MafjnoUacea, observed when young, present a character in the pith 

 which is far more general than that above mentioned; that the 

 existence of special cells almost always enables us to recognise them 

 on seeing only a fragment of a branch or stem; and that, finally, the 

 arrangement of these cells is, moreover, often sufi&cient to charac- 

 terize one of the series that we admit in this order. 



" One of the true MacjnoJiecB — that is, a Magnolia or a Tulip-tree — 

 is usually recognised by the following histological character : its 

 whitish pith is divided into segments by a series of transverse dia- 

 phragms of a more or less yellowish or greenish tint. These septa 



' Sec Teget. Kingd., 417. 



- GcEPPEET, Ueher die Anat. Struct, ein. 

 Magnoiiac, Linnma, xv. (1842), 135 ; Ann. Sc. 

 Nat., 8er. 2, xviii. 317. — Oliveu, Struct, of 

 the Stem in Bicotyl., 2. — Eichlee, Makt. 

 Flor. Bras., Magnoiiac, 139, t. 33. There is, 

 however, a slight difl'erence between the stems of 

 a Drimys and Araucaria as regards the general 

 direction of the cells of the medullary rays, which 

 have their longest diameter vertical in the former, 

 radial in the latter. 



3 EiCHLEK, Flora (186t), 449 ; Seem., 

 Journ. of Bot., iii. (1865J, 150. 



■* Oliveh, op. cil., 3. The fibres and vessels 

 here present punctations. The parenchyma is 

 covered with longitudinal rows of perforations, 

 " at least, on the surfaces transverse to the 



medullary rays." A. Geay {Introd. to Bot., 

 1858, 43, fig. 47) has represented these puncta- 

 tions in lUicium. Those of Winterece and 

 Canellece were noticed and compared with one 

 another by Miees [Ann. Nat. Hist., ser. 3, ii. 34). 

 Geiffith has made out {Notiil., iv. 715) the 

 existence of oblique perforations in the fibres of 

 Kadsura ; and Lindlet {Intr. to Bot., i. 66, 20) 

 has figured those of Spharostema. The Sclii- 

 zandrecB often contain large parallelopipedal or 

 prismatical crystals in their parencliyma, espe- 

 cially that of the pith. In Drimys we have 

 found cells with bundles of raphids, but only 

 very rarely. 



^ Compt. Bend, de I' Acad, des Sciences, Ixvi. 

 698 ; Adansonia, viii. 155. 



