NOTES AND ABSTRACTS. 
409 
Campanula sulphurea Boiss. By W. B. Turrill {Bot. Mag. t. 8827 ; Dec. 
1919). — A native of dry sandy places in Syria and Palestine, with intense yellow 
flowers, not quite hardy, and subject to the attacks of slugs. — F. J. C. 
Canada Thistle, Eradication. By A. A. Hansen {U.S. Dep. Agr., Farmers' Bull. 
1002, pp. 2-15 ; 4 figs.). — The Canada Thistle, Cirsium arvense, was introduced 
to the North American continent from Europe. It is chiefly distributed by the 
use of impure grass and clover seed. This pest may be eradicated by 
systematically destroying the top growth of the plant, using the sweep or knife 
type of cultivator, supplemented by the use of the hand hoe. Just before the 
thistle flowers, plough shallow, and later in the season use the disc harrow. The 
following spring plant a cultivated crop and see that no thistle tops survive. 
S. E. W. 
Capsid Bugs, Investigation of the Nature and Cause of the Damage to Plant 
Tissue resulting from the Feeding of. By K. M. Smith [Ann. App. Biol. vol. vii. 
no. I, Sept. 1920, pp. 40-55 ; 7 figs., i plate). — This research was to discover the 
cause of the damage done to apples, potatos, &c., by the capsid bugs, Plesiocoris 
nigricollis and Lygns pabulinus. 
It was definitely proved that mechanical means were not the chief agents of 
injury, but the injection into the plants' tissues of some dilute poison. When 
the salivary glands of these harmful capsid bugs were placed on cut slices of 
potato, a violent reaction took place which killed much of the tissue surrounding 
the glands, whereas on an injection of glands from the harmless apple bug, Psallus 
amhigims, the result was nil. — G. F. W. 
Carnation Stem Rot and its Control. By Geo. L. Peltier {U.S.A. Exp. 
Sin. III., Bull. 223, Sept. 1919, pp. 578-607; 5 figs.). — This disease is caused 
by Rhizoctonia Solani Kiihn {Corticium vagum B. & C), and is widely scattered 
in Illinois. It may attack stem cuttings, seedlings, or mature plants, and enters 
the plant at a point just below the ground level. Decay follows and soon 
sclerotia in large numbers are formed on the decomposed mass. Since the disease 
is a soil disease, the best methods of control are obviously in completely disin- 
fecting the soil ; but it is found that formalin, sulphuric acid, lime, Bordeaux 
mixture have but little effect upon the fungus. Steam sterilization is the only 
effective remedy. At the same time due care with regard to temperature and 
amount of moisture is essential if the plants are to be kept in a healthy 
condition. — A. B. 
Carnations. By H. Blin {Le Jard. vol. xxxiv. pp. 158-160). — In the cultiva- 
tion of Carnations for cut flowers, good results are obtained in soils containing 
humus by the use of chemical manures. Before the Carnations are planted out, 
the soil receives 220 lb. of superphosphate and 150 lb. of potassium sulphate 
per rood ; 45 lb. of sodium nitrate dissolved in water is applied in successive 
doses from April to October. During the flowering season the amount of 
potassium sulphate is increased and the mixture of superphosphate, nitrate 
and sulphate mixed in water and gradually applied to the plants to the great 
improvement in the size and colour of the flowers. — S. E. W. 
Catasetum. By J. Poupion {Rev. Hort. vol. xcii. pp. 98-100; 3 figs.). — 
Amateurs find a difficulty in flowering Catasetum, but good results are obtained 
by paying attention to the following points. The Catasetum requires a period 
of absolute rest at a temperature of 50-55" F. Water is withheld. In March the 
plants are taken out of their pots, the old compost is removed and withered roots 
and bulbs are cut off. They are repotted in ordinary pots half filled with pieces 
of charcoal and crocks and the remainder with sphagnum moss and polypodium 
fibre (1-2) and a little sand. They are placed near the glass in a house at 
68-70° F. When the roots show signs of growth, the pots are immersed in 
warm soft water. Spraying is prohibited. Towards the end of April the supply 
of water is limited as the flowering season begins. Exposure to direct sunlight 
is injurious. When the flowers are over the supply of water is increased, but 
it is stopped in November. — 5. E. W. 
Caulophyllum thalictroides. By J. Hutchinson {Card. Chron., Feb. 7, 1020, 
p. 63; I fig.). — Calls attention to the probability of this and the Asiatic 
C. robustum being one species. Also describes the curious fruit produced by the 
early falling away of the carpel, leaving two seeds on long funicles resembling 
two stalked fruits. — E. A. B. 
Cedar Apple Rust. By Cromwell {Iowa State Hort. Soc. Rep. 1918. pp. 127- 
131). — ^The cedar apple rust requires two hosts for its life cycle. The spores 
