688 SUMMARY OF CURRENT RESEARCHES RELATING TO 



this nematode on Cucurbiia, Coleus, and Begonia. It appears to be- 

 independent of external circumstances, and of the specific nature of the 

 host, and to consist in the production of large vesicular multi-nucleated 

 cells for the special nutrition of the parasite. 



C4) Structure of Organs. 



Flower and Fruit of the Paper-Mulberry.* — Prof. M. Mobius has 

 undertaken a detailed investigation of the flower and fruit of Brous- 

 sonetia papyri/era. Among the more interesting points are the following. 

 Broussonetia differs from Morus in the absence of rudiments of stamens 

 from the female flowers, while the male flowers possess the rudiment of 

 an ovary. The drupe is the result of an energetic growth of mesocarp- 

 cells of peculiar structure which the author terms the "rod-layer," 

 accompanied by splitting of the pericarp. As in Artocarpus, the axis 

 of the inflorescence contains medullary vascular bundles which are 

 wanting in the vegetative shoots. 



Sepaline and Capsular Hydathodes.f — M. K. Shibata adds four to 

 the 15 (all tropical) examples known of " water-calices," viz. Tecomo 

 (jrandiflora and Catalpa ksempferi (Bignoniaceoa), and Clcrodendrcm 

 tricliotomiim and C. squamalum (Verbenacese). The inside of the calyx 

 is furnished with capitate hairs which excrete water. In Sterculia 

 platanifoUa the follicle is, up to the time of bursting, filled with a 

 coffee-brown watery fluid, of an alkaline reaction, owing to the presence 

 of carbonates, which is also secreted from trichomes which clothe the 

 iuner surface of the follicle. 



Protuberances on the Branches of ^schynomene indica4— Sig. A. 

 Terracciano has investigated these structures, and iiuds them to be special 

 organs for enabling the branches to float when covered with water, and 

 to absorb the moisture of the air when exposed. The rootlets on the 

 submerged parts of the plant are true floating organs. The leaves 

 are provided with hydathodes which regulate the absorption and excretion 

 of water. 



Roots of Palmse and Pandanaceae.§— Herr G. Gillain describes the 

 specialities of the anatomy of the root in six families of palms, viz. the 

 Phceniciese, Sabalese, Borassefe, Lepidocaryeaa, Ceroxyleae (including 

 Areceae and Caryotea3), and ( 'ocoineas, which together with the Phyt- 

 elephanteae, make up the order Palmae. To this is appended an 

 account of the same organs in the Pandanaceas derived from the genera 

 Pandanus and Freycinetia. 



Mangrove-Vegetation. || — In a series of papers on the flora of the 

 Danish West Indies, F. Boergesen and 0. Paulsen give an interesting 

 account of the trees which constitute the swamp-flora, belonging to the 

 orders Rhizophoraceas and Verbenaceae, especially BhizopJwra Mangle, 

 Avicennia nitida, and Laguncularia racemosa. The aerial roots of 



* Pringsheim's Jahrb. f. wiss. Bot. xxkiv. (1900) pp. 425-56 (7 figs.), 

 f Arb. bot. Inst. k. Univ. Tokio. See Bot. Centralbl., lxxxiii. (1900) p. 350. 

 X Contrib. Biol. Veget., ii. (1899) pp. 195-206, Palermo. See Bot. Centralbl.. 

 lxxxiii. (1900) p. 115. 



§ Bot. Centralbl., lxxxiii. (1900) pp. 337-45, 369-80, 401-12 (1 pi.). 

 II Rev. Gen. de Bot. (Bonnier), xii. (1900) pp. 225-45 (45 figs.). 



