156 Morphologie. — Teratologie. 



Guffroy, Avoine elevee et avoine ä chapelet. (Bull, de 

 l'Ass. franc. de Bot. 5. Armee. No. 54. juin 1902. p. 135 

 — 136.) 



L'Avoine ä chapelet (A bulbosa Willd. et syn.) consideree par cer- 

 tains auteurs comme une variete de IM. elatior, serait une deformation 

 pathologique de celle-ci, la presence des renflements du rhizöme s'etant 

 toujours trouvee liee ä celle de nombreuses bacteries. C'est un nouveau 

 cas de tuberisation par parasitisme d'autant plus interessant que certains 

 ont tendance ä attribuer une cause de cet ordre ä toutes les formations 

 de tubercule (cf. Noel Bernard, Etudes sur la Tuberisation in Rev. 

 generale de Bot., 1902. No. 157—162). Henri Hua. 



PLONER, INNOCENZ, Der stetige Wandel im typischen Bau- 

 plane des pflanzlichen Organismus. (Programm des 

 öffentlichen Privat-Obergymnasiums der Franciscaner zu Bozen 

 am Schlüsse des Schuljahres 1901/02. Bozen 1902. 8°. 

 p. 1—24. Mit 6 Abbildungen.) 



Erläuterung des Satzes: Das Bildungsgesetz der organischen Körper 

 ist nicht constant. Darlegung der Veränderungen im Blüthenbau über- 

 haupt, der Verwachsungserscheinungen im besonderen. Besondere Auf- 

 merksamkeit wird der Verwachsung der Blüthenträger bei Leontodon 

 Taraxacum, der Synanthie bei Prunus spinosa und bei anderen Pflanzen 

 gewidmet. Matouschek (Reichenberg). 



Wright, Herbert, Observations on Dracaena reflexa Lam. 

 (Annais of the Royal Botanic Gardens, Peradeniya. Vol. I. 

 1901. p. 165—172. With plate.) 



The species is remarkable for the complex nature of its 

 branching System. The specimen which is the subject of this 

 paper was introduced into the Peradeniya Botanic Gardens in 

 1847. Its height is 10 metres; the diameter of the space 

 covered by its branches is 9 metres; the main stem is short, 

 irregulär in outline and nearly 3 metres in circumference. 



The germination of the seed and development of the 

 seedling are briefly described. The first indications of a vascular 

 •cambium appeared in a seedling nearly 7 (seven) weeks old. 

 The cambium appeared in the pericycle of the very short 

 hypocotyl immediately below the cotyledonary node and thence 

 advanced upwards and down-wards. In the plants examined 

 the cambium, once started in the stem, produced a radial row 

 of 4 vascular bundles in 6 months. Eleven (11) bundles were 

 formed in 12 months. 



In the root of D. Draco and D. fragrans Scott and Brebner 

 shewed that cambium was first formed at the insertions of the 

 rootlets, where the maximum thickness of the secondary zone 

 is attained. In D. reflexa, on the other hand, Strasburger 

 states that the cambium starts and attains maximum thickness 

 at the base of the adventitious root and tapers off regularly 

 towards the root-apex. Strasburger's Observation is 

 confirmed by the author who however also finds that, at least 

 occasionally, the cambium arises at the insertions of the rootlets 

 as in D. Draco and D. fragrans. The place of its origin is 



