NOTES AND ABSTRACTS. 



469 



Cowpeas Growing in Missouri. By M. F. Miller (U.S.A. St. Bd. 

 Hort. Missouri, vol. x., no. 1 ; Jan. 1912 ; plates). — It is pointed out 

 that the cowpea is a plant that is not sufficiently appreciated by the 

 Missouri farmer. Its value as a soil renovator, as a green manure 

 crop, as a catch crop, as a pasture and as a regular hay crop, gives 

 it a place in Missouri agriculture which warrants its wide acceptance 

 by farmers. Its wide adaptation to the soils and to the climatic 

 conditions common to Missouri make it a crop that can be readily 

 grown in practically every part of the State, and there is little doubt 

 that its use is destined to a great increase. Certain drawbacks have 

 hitherto kept it from taking the place it deserves. Among these Are 

 the high cost of the seed and the difficulty in curing the hay. The 

 gradual introduction of cowpea shellers that will release the peas 

 without cracking them will undoubtedly overcome the first of these 

 difficulties to a considerable extent, while proper methods of handling 

 the hay will in a great measure do away with the latter drawback. The 

 writers' assertions are backed up by articles contributed by other 

 experts on the value of the cowpea in building up the soil, on the 

 feeding value of the cowpea, &c, and directions are given for the 

 preparation of the soil, on the order of the cowpea in a rotation of 

 crops, and for its cultivation. 



The bulletin ends with a short note on the soy-bean. — M . L. H. 



Crown Gall, The Structure and Development of : a Plant Cancer. 



By Erwin F. Smith (U.S.A. Dep. Agr., Bur. PL Ind., Bull. 255; 

 1913). — This is a bulletin on the histology of crown gall (caused 

 by Bacterium tumefaciens) . 



The writer has experienced considerable difficulty in differentiating 

 the organism in stained sections. The best results have been obtained 

 with material impregnated with chloride of gold. 



Diseased tissue was found to stain deeply with potassium chromate 

 and neutral ammonium chromate, whereas normal tissue was only 

 feebly stained. 



A general summary of previous work on this organism by the same 

 author is given. 



The bacterium is a soil organism and a wound parasite, and the 

 author considers the relation between host and parasite to be one of 

 symbiosis, in which the parasite has the advantage. The organism 

 can be easily isolated from the tissues of the gall and grows readily 

 on the ordinary culture media. 



The bacteria are not abundant in the cells ; and they occur inside the 

 cell but outside the nucleus. The author considers that the injury 

 is mostly due to the by-products formed during the development of 

 the organism and the reactions set up by the cells against the intruding 

 organisms. 



A large number of plates of microphotographs of diseased tissue 

 are given. — D. M. C. 



