NOTES AND ABSTRACTS. 



161 



Phosphorus in Flat Turnips, as Influenced by Amount available in Soils, The 

 Percentage of Total. By Burt L. Hartwell (U.S.A. Exp. Sin., Rhode I., 

 Bull. 154, April 191 3). — The addition of phosphates to various soils increased 

 the amount of phosphorus in turnips, the quantity depending upon the type 

 of manure given. 



It is suggested that a good practical way of ascertaining the amount of available 

 phosphorus in the land would be to grow a crop of turnips and estimate there- 

 from.— C. P. C. 



Pimelea ferruginea [Dot. Mag. tab. 8574). — W. Australia. Nat. Ord. Thymela- 

 ceae, tribe Euthymelaceae. Shrub, to 2 feet high. Leaves opposite, under £ inch 

 long. Heads terminal, globose, many-flowered, i \ inch across. Perianth rose- 

 coloured. — G. H. 



Pltwood Trade in the Midlands. By A. Slater (Quart. Jour, of Forestry, vol. 

 ix. No. 2, pp. 134-137 ; April 1915). — Early in September foreign pit-wood was 

 quoted at 35s. the ton ex boat, Cardiff, and in less than two months fluctuated 

 down to 19s. 6d., and again has steadily risen, and at the time of writing these 

 notes (end of February) it has reached the high price of 37s. the ton. Yet at 

 this high figure I doubt whether anyone disposing of home-grown pitwood can 

 realize anything like the same net return as could be obtained last September. 

 If anyone were to be blamed for the sudden rise in prices for native pit timber, 

 it should be laid on the shoulders of the pit-owners themselves ; and the public 

 remark made by the chairman of a well-known colliery company, stating that 

 the supply of native timber suitable for pit-wood would only last a few months, 

 no doubt, was seriously taken by the general public and even colliery- owners. 



There are at the present time, I think, two reasons affecting the sale of home- 

 grown pit- wood : first, the timber is often situated a considerable distance from 

 a railway station, and the haulage to it is not only an exceedingly expensive 

 item, but it is very difficult even to get hauliers who can undertake to find 

 horses and men ; secondly, the heavy carriage imposed by railway companies 

 for the carriage of home-grown pit- wood. — A. D. W . 



Plant Diseases in Connecticut. By G. P. Clinton, Sc.D. (U.S.A. Agr. Exp. 

 Stn., New Haven, Conn., July 191 4, pp. 1-42 ; 8 plates). — This gives details of 

 the various plant diseases which have been investigated in Connecticut during 

 1913. Amongst the bacterial diseases of plants are the Heart Rot of Celery, 

 the Soft Rot of the Parsnip and the Salsify (Bacillus carotovorus Jones), the 

 Black Leg of the Potato (Bacillus phytophthorus Appel), which was formerly 

 confused with Bacillus Solanacearum ; and Crown Gall on the Spindle Tree 

 (Bacterium tumefaciens Sm. and Towns.). This last is a new host for B. 

 tumefaciens, which has been previously reported on the apple, blackberry, plum, 

 peach, raspberry, rose, white poplar, and wistaria. — A. B. 



Plant Pathology, Problems and Progress in. By L. R. Jones (Amer. Jour. 

 Bot. vol. i. March 1914, pp. 97-11 1). — A stimulating and inspiring address by 

 the retiring President of the Botanical Society of America, dealing with the 

 problem of parasitism ; the life-history problems ; the culture problem ; bacteria 

 in relation to plant disease ; the relation of parasite to host and environment ; 

 the non-parasitic disease ; and the problems of disease control. 



The Problem of Parasitism. — Our knowledge owes much to De Bary, who 

 demonstrated the true relation between fungus and the host plant, but we 

 have scarcely begun the study of the intimate relations of parasite and host, 

 the conditions and the results of parasitism. 



The Life-history Problems. — Attention was drawn to the classical examples. 

 Kiihn's work on grain infection by smut ; De Bary's work on the life-histories 

 of the Peronosporales and the heteroecism of the rusts. Discoveries as to the 

 life-histories of parasites are of more practical importance for disease control than 

 demonstrations with spray mixtures ; the last are transient, the first are 

 permanent contributions. 



The Culture Problem. — The monumental work of Pasteur in the cultivations of 

 yeasts and bacteria, and the rise of the science of bacteriology and pure cultures, 

 were referred to. The value of solid over liquid media is increasingly established. 

 The process of inoculation has not yet been fully realized in plant pathology. 

 It is only thus that we can learn of the species susceptibility of hosts and the 

 occurrence of biological forms amongst parasites — both of paramount importance, 

 economically and scientifically, in plant pathology. 



Bacteria in Relation to Plant Disease. — The early work of Burrill and the recent 

 work of E. F. Smith were especially dealt with. 



VOL. XLI. M 



