NOTES Ax\D ABSTRACTS. 



515 



Colour Chemistry of Flowers. (1) By A. E. Everest ; (2) by M. Wheldale (Jour. 

 Gen. iv. pp. 361-376). — Two papers upon the anthocyanin colours of flowers. 

 The authors of the two papers do not appear to be in agreement as to the inter- 

 pretation of the results obtained. — F. J. C. 



Conifers, Notes on. By A. Bruce Jackson (Gard. Chron. 1915-16). — A 

 continuation of critical notes with figures. The following are dealt with : 

 Cupressus Lawsoniana, Oct. 30, p. 272, with 3 figs. ; C. nootkatensis, Dec. 18, 

 p. 374, 2 figs. ; C. pisifera, Jan. 29, p. 58, 1 fig. — E. A. B. 



Conifers, Pacific Coast, Insect Damage to the Cones and Seeds of. By John 

 M. Miller (U.S.A. Dep. Agr., Bull. 95, July 9, 1914). — Character and Cause of 

 Damage. — Damage to the seed of conifers is caused by various species of insects 

 which feed upon the buds, flowers, immature cones and seed, and mature seed. 

 Great damage is accomplished while the cones are immature and before the 

 seed ripens. Cones which are infested or " wormy" are often found when the 

 areas for seed collection are being located. Wormy cones and seeds are caused 

 by the adults and grubs of small beetles, the " worms " or caterpillars of moths, 

 the maggots of gnats, and the larvae of tiny wasps known as seed chalcidids. 

 With the exception of the cone beetles, the adult insect is seldom found in the 

 immature cone. The insects may be found in almost any part of the cone or 

 seed, the feeding habits varying much with the different species. In many cases 

 the presence of these insects in the cone is evident, and may be recognised by the 

 peculiar type or class of injury. Where this is the case the damage may be 

 approximately estimated in the summer. 



Indications of Insect damage. — Attacks of the cone beetle in the seed crop are 

 indicated by a small entrance-hole at the base of the cone, with castings or small 

 pitch tubes, during the early summer ; later, by the brown, withered appearance 

 of the cone. 



The attacks of the cone moth may sometimes be recognized by little masses 

 of pitch and larval castings on the surface of the cone, and sometimes by withered 

 cones, but it is best to look for the caterpillar among the scales and in the seed 

 and pith. It is always best to cut the cone open, sectioning it several different 

 ways, in making the examination. 



The attacks of the fir-cone maggot can also be found by cutting or breaking 

 the cone open. The larval mines will be found in the scales and seeds, in which 

 will usually be found the small, white, active larvae. 



An intelligent selection of the seed-collecting areas w r iirprevent - much of the 

 loss due to gathering seed which is afterwards found to be infested or worthless. 



A. D. W. 



Copper Carbonate as a Fungicide. By G. P. Darnell-Smith (Agr. Gaz. N.S.W, 

 vol. xxvi. pp. 242, 243). — Instead of pickling wheat seed in copper sulphate 

 solution, shaking the seed up with powdered copper carbonate is equally 

 efficient as a fungicide. — S. E. W, 



Corylus mandshurica (Bot. Mag. tab. 8623). — Eastern Asia. Family Cupuli- 

 ferae. Tribe Coryleae. Shrub, 15 ft. in height. Leaves sub-orbicular, 2 £-6 in, 

 long, double-serrate. Male catkins 1-3 together. Involucre closely investing 

 the nut, globular at the base, but produced into a tube, 2 in. long, hispid, not 

 depressed, globose, £ in. wide. — G. H. 



Cotoneaster pannosa (Bot. Mag. tab. 8594). — Western China. Family 

 Rosaceae. Tribe Pomaceae. Shrub with deciduous foliage, 8 ft. high. Leaves 

 ovate, £-1 J in. long, dull green. Corymbs, in. wide. Corolla £ in. across, 

 white. Fruit oval, £in. long, deep red. — G. H. 



Cotton Wilt and Root-knot. By W. W. Gilbert {U.S.A. Dep. Agr., Bur. 

 PI. Ind., Farmers' Bull. 625, Dec. 1914, pp. 1-24 ; 15 figs.). — Both cotton wilt and 

 root-knot occur in all the cotton -producing States from North Carolina to Texas ; 

 the first is particularly prevalent in South Carolina, Georgia, and Alabama, while 

 the root-knot is rather more generally distributed in the same areas. 



Cotton Wilt is caused by the fungus Fusarium vasinfectum Atk. This, enter- 

 ing the roots of the plant from the soil, passes into the vascular tissue, especially 

 the wood vessels, and, growing vigorously, prevents the ascent of water to the 

 stem. This soon causes the plant to wither and finally die. The fungus produces 

 a variety of spores, including macroconidia, microconidia, and chlamydospores. 

 Fusarium causes similar wilting in tomato, potato, water-melon, cowpea, &c. 



As a rule, this disease occurs on soils of a sandy or sandy-loam nature, seldom 

 on clay soils, and appears to be favoured by abundant soil moisture. 



