246 EXPERIMENT STATION RECORD. 



The rubber plant of southern Europe, Mattki and (I. Yxn dkn Kerckiiovi; 

 ( Imlid Rubber World, 37 (H'O^^), AV>. 6", /*/>. 177-17!!. fi</. I. inaii I). — An account, 

 iiichulinjj: historical notes, botanical description, geographical distribntion, and 

 nses, is given of a gum-yielding species of plant, Atracti/Ua (/iimmifcra, native to 

 the Mediterranean region both in Europe and Africa. Several analyses were 

 made of this gum and show a rubber content of from 22.90 to 3G.4G per cent, 

 with about double that amount of resin. The plant, which appears to have been 

 known from remote times, grows mostly underground in the shape of a large 

 cylindrical trunk, often weighing from 20 to 40 lbs. The leaves grow close 

 to the ground. The Sicilians are said to free the rubber from the resin by 

 chewing the gum. The rubber is then dissolved in spirits of turpentine in order 

 to make a sort of bird lime for catching birds. 



Although it is not believed that the gum of Atractylis can take the place of 

 rubber, it is thought that it may be adapted to mixing with it in the same man- 

 ner as the gums of guayule and pontianak. 



Hints on the cultivation of Para rubber, A. W. Bartlett (Separate from 

 Off. Gaz. [British Guiana], 1907, April 17, pp. 3). — Brief practical suggestions 

 are given relative to the methods of packing' Para seed for shipment, sowing, 

 planting operations and distances, shade and protection from wind, intercrops 

 and catch crops, green manuring, and pruning, 



DISEASES OF PLANTS. 



Notes on some plant diseases, L. Savastano {Bol. Arbor. Ital., 4 (1908), 

 No. 1, pp. 21-32). — Descriptions are given of a number of obscure diseases of 

 citrus trees and fruits, among them a retardation of the growth of orange trees 

 following transplanting, drying of oi'anges and lemons on the trees, lemon 

 scald, sunburn of the fruit, etc. Notes are also given on vine chlorosis, a dis- 

 ease of alder trees, the biologj' of the downy mildew of the grape, grape powdery 

 mildew, etc. 



Fasciations of known causation, H. Hus (Amer. Xat., Jf2 (1908), Xo. /f94, 

 pp. Sl-97, figs. 2). — A description is given of a number of forms of fasciation, 

 the causes of which are grouped under four heads : Mechanical causes, cases 

 where no injury can be traced, the action of fungi, and the action of insects. 



Experiments in combating plant diseases, F. K. Ravn and A. Madsen- 

 Mygdal {SamvirJc. Landbofor. Fyens Stift, 1906, pp. 2'f). — The report covers 

 experiments on the prevention of smut in spring grains by the hot-water and 

 the formaldehyde methods, studies on barnyard manure as a carrier of con- 

 tagion of the club-root disease, and experiments on the application of lime as 

 a remedy against the chib-root disease. The work along these lines will be 

 continued. 



Texas root rot of cotton: Field experiments in 1907, C. L. Shear and G. F. 

 Miles (U. S. Dept. Agr., Bur. Plant Indus. Circ. 9, pp. 3-7, fig. /). — In a jire- 

 vious publication (E. S. R., 19, p. 247) an account is given of the beneficial 

 effect of deep fall plowing and a rotation of crops for the control of the root 

 rot of cotton, due to Ozonium omnivorum. In the present publication a more 

 detailed statement is given of further experiments in cultivation and rotation 

 of crops for the control of this disease. It is stated that by rotation with im- 

 nnnie crops, a field which in 1904 was planted to cotton with a loss of 9.5 per cent 

 from the root rot, was, after two seasons with corn and wheat, again planted 

 to cotton in 1907, when the crop was but slightly affected by the root rot. It 

 seems probable that a combination of rotation of crops and deep fall plowing 

 will prove a satisfactory, eflicient, and practicable means of control. 



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