NOTES AND ABSTRACTS. 



465 



useful for house decoration. They are raised from seeds which are 

 ten to twelve weeks in germinating, in a temperature of 53 0 to 6o° F. 

 C. elegans is perhaps the best worthy of cultivation. Several hybrids 

 have been obtained, e.g. C. corallina x elatior, elegans X concolor. 

 The hybrids resemble the male parent. — S. E. W. 



Chamaedorea glaucifolia (Bot. Mag. tab. 8457). — Colombia? 

 Family Palmae, tribe Areceae. Shrub, stem slender, 15 feet. Leaves, 

 ascending, leaflets forty, linear-lanceolate. Panicles, male, 16 inches. 

 Corolla 2 J inches long. Fruit globose, J inch diameter, black, polished. 

 — G. H. 



Chestnut, The Bark Disease {U.S.A. Exp. Stn., W. Virg., Bull. 137). 

 This bulletin is chiefly a summary of all available publications on the 

 subject of the dangerous bark disease of chestnuts due to Diaporthe 

 parasitica, which is causing such damage in the United States. — D. M. C. 



Chironia laxa [Bot. Mag. tab. 8455). — South Africa. Family 

 Gentianaceae, tribe Chironieae. Herb, glabrous. Stems laxly 

 branched. Leaves f-i inch long. Flowers showy, usually 2-3, 

 or solitary, terminal. Corolla pale magenta, 2-2J lines across. — G. H. 



Cicadas. By W. W. Froggatt (Agr. Gaz. N.S.W. vol. xxiv., 

 pp. 341-344 ; 3 figs.). — In the neighbourhood of Sydney much damage 

 has been done to the bark of Peach and other trees by cicadas (Melam- 

 psalta incepta). — S. E. W. 



Cissus Species, Growth of the Aerial Roots of a. By Dr. A. H. 



Blaauw (Ann. Jard. Bot. Buit. ser. ii. vol. xi. pt. ii. pp. 266-293, 

 1912 ; two text figs.). — Cissus pubiflora var. papulosa grows high 

 up on the trees in the primeval forests round Tjibodas. Its aerial 

 roots, sometimes 20-30 metres in length, reach down to the ground, 

 and after a time emit lateral branches which root into the soil. These 

 rapidly- growing roots appeared to be favourable objects upon which 

 to study the phenomenon of growth. The root apices were carefully 

 marked with small dots of a black pigment which would not wash 

 away with the rain. It was found that the total growth of a root 

 during a day averaged about 7 cm. This would imply (if the condi- 

 tions remained constant) that such a root would grow 20 metres in 

 ten months. 



Growth is most marked at the apex of the root, and gradually 

 lessens from point to point behind this. This falling off of growth is 

 not regular, however, and there is no single zone of maximum growth 

 to be observed. 



Growth is much slower during the day than in the night. Between 

 the hours of 4 p.m. and 8 a.m. twice the growth takes place in the zone 

 0-10 cm., and three times the growth in zone 10-20 cm., compared with 

 that which is observed in these regions during a similar period of time 



