168 NATURAL HISTORY OF PLANTS. 



remarked by Lindley' for possessing areolate punctations like those 

 of the Conifers, or rather of Jraucaria. 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. Troi-hodcndroii, whose place among Mat/noViacea had been con- 

 sidered doubtful, presents the same peculiarity.' The Magnoliem 

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

 alternating with those of woody fibres, and in this respect return to 

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

 Eupldca,^ very closely allied to Trovhodvndron. 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 

 Magnoliacea, 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 

 arransrement of these cells is, moreover, often sufficient to charac- 

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



" One of the true Magnoliea — 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 Veget. Kingd., 417. mwlullary rnys." A. Ghay {In/rod. to Bot., 



' GcEPrEUT, Ueher die Anat. Struct, ein. 1858, 43, fip. 47) 1ms reprcticiiti.tl these puiicU- 



Magnoliac., Linntta, xv. (1812), 1U5; Ann. Sc. tioiis in Illicium. Those of Winferett and 



Ifat., 8tT. 2, xviii. 317. — Olivf.u, Slntci. of Canellea were noticed and c<in>|)nred with one 



the Stem in Uicoli/l., 2. — Eiciilkh, Mart. another by Mi khs (-•!««. Aa/. //i.t/., ser. 3, ii. 34). 



Flor. Brat., Magnoliac, 139, t. 32. There is, Ghiffitu hiis made out {Hotul., iv. 715) the 



however, a Hliglit dillerence between the stems of existence of obrujue perfonitions in the fibres of 



a Drimyt iind Araucaria us regards the general Kadsura ; and Lindi.ky (/w/r. to Bot., i. G6, 20) 



direction of the cells of the medullary rays, which has figured those of Spfittrostrma. The NcA»- 



have their longest diameter verticid in the former, zandmr often contain large paruUelopipedal or 



radial in the latter. prismutical crystjds in their parenciiyma, espe- 



* EiciiLKU, Flora (18G4), 441); Sekm., ciuUy that of the pith. In Drimyt wo have 

 Joum. of Hut., iii. (18(55;, \M. found cells with bundles of ruphids, but only 



* Olivkk, op. fit., 3. The fibres and vessels very rarely. 



here present punctaitions. Tlio parenchyma is * Compt. Rend, de VAcad. det Scieiuft, Ixvi. 



covered with longitudinal rows of perforations, 01)8 ; Adatuoniti, viii. 155. 

 "at least, on the surfaces transverse to the 



