84 Anatomie. — Biologie. 



thin and possesses many somewhat depressed stomata; mechanical 

 tissue is little developed, and the medulla contains large air Spaces. 

 In the Sclerocyperaceae the epidermis shows no stomata and is sub- 

 tended by a continuous zone of sclerenchyma. Lysigenous air ca- 

 vities alternate with the bundles. A table of aerial stem characters 

 is given. 



Evidence of cambial activity has been found in nearly all the 

 species examined The leaf-trace bundles after their entrance join 

 in the anastomosis and then pass down the stem for one internode as 

 cortical bundles. The cauline bundles are continuous through the 

 whole length of the stem and join in the nodal anastomosis. There 

 is a reduction of bundles in the floral axis and, except where the 

 involucral leaves are large, all the bundles are collateral and arranged 

 in a Single ring. This is considered to be primitive. 



The author concludes that amphivasal bundles are derived from 

 collateral bundles by multiplication of the xylem elements, resulting 

 from the introduction of large and numerous leaf traces into the cen- 

 tral cylinder. The leaf is the dominent factor in the development 

 of the Monocotyledonous stele. The simple tubulär stele is ancestral, 

 and medullary Strands, amphivasal bundles, and nodal complexes 

 are acquired characters. He considers that the Cyperaceae are one 

 of the more primitive groups of the Monocotyleclons, are considerably 

 speciallised, and reduced from the megaphyllous, possibly hygro- 

 philous ancestor. Their anatomy points strongly to the derivation of 

 Monocotyleclons and Dicotyledons from a common ancestor with 

 essentially Dicotyledonous characters. M. Wilson (Glasgow). 



BORZi, A., Produzione d'indolo e impollinazione della 

 „Visnea Mocanera" L. (Atti della R. Accad. Lincei. Xlli. 1904. 

 8". p. 372.) 



Les fleurs de la Visnea Mocanera L. n'ont pas de dispositions 

 vexillaires pour attirer les insectes, mais elles r^pandent une odeur 

 tres d^sagr^able qui ressemble ä celle des substances animales en 

 putr^faction. L'auteur a voulu voir, par l'analyse chimique, si cette 

 odeur dtait due ä la prdsence de composds indoliques. II a traitd 

 pour cela les fleurs avec une Solution d'acide oxalique chauffee 

 jusqu'ä 100". La coloration rouge-carmin que prenaient les s^pales 

 dtait la preuve de la prdsence de ces substances. Pour confirmer 

 ces experiences, il a fait la r^action de la lignine, en employant au 

 Heu de scatol, les fleurs memes. Au microscope la reaction s'exä- 

 cute en pulvdrisant d'acide oxalique la prdparation. 



Pavolini (Fiorence). 



Penzig, 0., Noterelle biologiche. (Malpighia. Anno XVIII. 

 [1904.] p. 188.) 



Sur une galle de „Toddalia aculeata Pers.", l'auteur a observ^, 

 pendant son sejour ä Ceylan, des fruits bien ddveloppt^s comme 

 ceux produits par les fleurs femelies, sur les inflorescences mäles 

 de la Toddcilict acnleata Pers. Une Observation plus soign^e lui 

 a x€v€\€ que les pretendus fruits n'dtaient que des galles charnues, 

 parcourues par les galeries d'un insecte jusqu'ä präsent inconnu, qui 

 a €{€ trouvd seulement ä l'etat de nymphe: il parait appartenir au 

 groupe des rostricides (Microlepidopteres). 



Un cas de symbiose entre les fourmis et les cicadelles. — 

 Dans l'ile de Java, Penzig a observä sur toutes les plantes 



