70 CEREAL RUSTS OF THE UNITED STATES. 



(13) The crown rust of oats is not yet known to winter its uredo nor 

 to transfer to any other hosts than species of Avena.' 



(14) The black stem rust of wheat occurs also on barley and Hordeum 

 jubatum. So far as known it does not winter its uredo in this country. 



(15) It has not yet been definitely determined whether there is a dis- 

 tinct form of the black stem rust on rye in this country, but it is very 

 probable that there is. 



(16) The uredo of the black stem rust of oats is not yet known to 

 winter in the United States, but it has been found alive very late in 

 the autumn. The rust, however, is also common on the two grasses, 

 Dactylis glomerata and Arrhenatherum elatiuSy hence oats maybe easily 

 infected with it when grown in close proximity to these grasses. 



(17) Maize rust occurs also on teosiute in this country, but does not 

 winter its uredo. It is of little economic importance. 



BIBLIOGRAPHY.^ 



The following is a list of the writings consulted most in preparing 

 this bulletin : 



1. Arthur, J. C. What is Common Wheat Rust? Proc. Soc. Prom. Agr. Sci., 1889, 



pp. 11, 12. 



2. Barclay, A. A Descriptive List of Uredinese Ocourring in the Neighborhood of 



Simla, western Himalayas. .Four. Ass. Soc. Bengal, 1887, Vol. LVI, Part II, pp. 

 350-375; 1889, Vol. LVIII, Part II, pp. 232-251; 1890, Vol. LIX, Part II, pp. 

 75-112. 



3. Barclay, A. Additional Uredineaj from the Neighborhood of Simla. Jour. 



Ass. Soc. Bengal. 1891, Vol. LX, Part II, pp. 211-230. 



4. Barclay, A. On the Life History of PMCcmia coro«a/a var Inmalanensis. Trans. 



Linn. Soc, 2d ser. (1891), 1894,"^ Vol. Ill, pp. 227-236. 



5. Barclay, A. On Some Rusts and Mildews in India. Jour. Bot., 1890, Vol. 



XXVIII, pp. 257-261; 1892, Vol. XXX, pp. 1-8, 40-49. 



6. BoLLEY, H. L. Subepidermal Rusts. Bot. Gaz., 1889, Vol. XIV, pp. ] 39-145. 



7. BOLLEY, H. L. Wheat Rust. Ind. Agr. Expt. Sta. Bull. No. 26, 1889. 



8. BoLLEY, H. L. The Heteroecismal Uredinea). Am. Mon. Micr. Jour., 1889, Vol. 



X, pp. 169-180. 



'As already mentioned, later experiments show that the a>,cidium of Bhamnua 

 lavccolata infects oats, PhaJaris caroliniana, and Arrhenatherum elaiius. 



2 Since this bulletin was prepared Dr. H. Klebahn has published in Zeitschr. fiir 

 Pflanzenkrank., Feb. 4,' 1899, Bd. VI?I, Heft 6, pp. 321-342, a lengthy article entitled 

 "Ein Beitrag zur Getreiderostfrage." It consists chiefly in an account of experi- 

 ments made with the different grain rusts, aud of the results, which seem to conflict 

 more or less with those obtained by Eriksson. In Centralbl. f. Bakt., Parasit., u. 

 Infekt., Dec. 19, 30, and 31, 1898, Abt. II, Bd. IV, pp. 855-859, 887-896, 913-910 

 (6 illus.) appears an article by Prof. H. L. Bolley, entitled "Einige Bemerkungen 

 liber die symbiotische Mykoplasmatheorie bei dem Getreiderost," in which the 

 author, on the b.asis of his own experiments, also criticises Eriksson's theory, and 

 gives the results of other iuvestigatious, which show the great vitality of uredospores 

 and ajcidiospores aud the possibility of uredospore germ tubes passing through the 

 actual epidermis of the leaf as well as the stomata. The original of this paper (in 

 English) was presented before the Boston meeting of the American Association for 

 the Advancement of Science, August, 1898. 



