180 Anatomie. — Biologie. 



complexity originate at the node and spread afterwards down- 

 wards through the internode. From this point of view it is 

 pointed out that the acropetal method of describing tissues 

 gives one their morphology, tissues within the stele being taken 

 as belonging to the stele; while tracing the tissue downwards 

 leads more to a description of the phylogenetic history of the 

 tissues expressed in physiological terms. 



D. J. Gwynne-Vaughan. 



Chick, Edith, The seedling of Torreya Myrlstica. (The New 

 Phytologist. Vol. II. 1903. Nos. 4 and 5. p. 83—91. 

 Plates VII and VIII.) 



The tips of the two colytedons lie within the seed and 

 are frequently fused together; they also shew a tendency 

 to become lobed. In the root the stele contains a diarch xylem 

 plate. As the stem region is approached a pith appears in the 

 centre of the xylem, the protoxylem elements disappear and 

 finally the metaxylem breaks up into several separate portions. 

 Each cotyledon is supplied with a single vascular Strand the 

 protoxylem of which is central. The protoxylem consists of 

 annular and spiral elements which, however, have a double 

 origin ; those towards the abaxial side belong to the cotyledon 

 alone, while those on the adaxial side are connected below 

 with the metaxylem of the root. At about the middle of the 

 petiole a considerable amount of centripetal xylem is to be 

 found consisting of elongated scalariform or pitted tracheides. 

 Transitional forms between these and the large, almost cubical, 

 scalariform and pitted elements of the transfusion tissue on the 

 adaxial side of the trace are also present. No centripetal 

 xylem was found in the epicotyl or in the first leaves. The 

 author favours the view that the transfusion tissue arose from 

 the parenchyma and not from the centripetal xylem. 



D. J. Gwynne-Vaughan. 



Armari, B., Contribuzione allo studio delT Influenza 

 del clima e della stazione sopralastruttura delle 

 plante della regione mediterrane a. (Annali di 

 Botanica pubblicati dal Prof. R. Pirotta. Vol. I. Fase. i. 

 1903. p. 17—41. Tav. II.) 



On trouve chez les plantes qui vivent dans la region 

 mediterraneenne quelques adaptations pour la defense contre la 

 secheresse de Tete obtenues par les moyens les plus divers; 

 en s'appuyant sur la diversite de ces moyens, dont il donne 

 la description detaillee, l'auteur distribue ces plantes dans les 8 

 types suivantes: 



P Plantes presque toujours depourvues de feuilles (Spartium 

 junceiim L., Retama monosperma Lam.) ; 



2° Plantes avec feuilles reduites, stomates enfonpes dans la 

 tige et proteges par de poils (Genista aetnensis D.C.); 



