DISEASES OF PLAISTTS. 751 



times during the growing season in the morning while the clew is still upon 

 them. 



Bacteriosis of Iris pallida, F. Cavaka (BuL Soe. Bot. Ital., 1911, No. 6, pp. 

 ISO-lS-i; abs. in Internat. Inst. Agr. [Rome], Bui. Bur. Agr. Intel, and Plant Dis- 

 eases, 2 (1911), No. 7, pp. 1795, 1796).— A preliminary note is given on a dis- 

 ease observed in beds of /. pallida in Florence in the spring of 1911. The 

 plants showed a yellowing of the leaves, which finally faded and rotted at the 

 base, accompanied by the rotting of the I'hizomes. 



A study of material showed that the disease was doubtless due to some 

 species of bacteria. Inoculations of material isolated from leaves were always 

 successful in producing the disease in the leaves but not upon the rhizomes. 



The experiments seemed to indicate that the development of the micro- 

 organism is hindered during the hot dry season, and this conclusion was sup- 

 ported by observations made in the infected locality. The author believes 

 that the disease is due to special circumstances, such as a fall of temperature 

 in winter, causing the reserve starch to change into dextrin ; or to excessive 

 atmospheric moisture, favoring the development of the bacteria. 



Similar diseases of Iris have been noted by different authors, and the dif- 

 ferences between the organism occurring on /. pallida and the others are 

 being studied. 



A study of some Glceosporiums and their relation to a sweet pea disease, 

 J. J. Taubenhaus [Phytopathology, 1 (1911), No. 6, pp. 196-202, pi. 1, figs. 

 12). — The author's attention was called in July, 1910, to a serious anthracnose 

 of the sweet pea at the Delaware Ex;periment Station, and an investigation 

 proved it to be the same as that reported by Sheldon in 1905 (E. S. R., 17, 

 p. 264). 



The disease occurs on the stems, flowers, and pods, but most severely on the 

 latter. There is a general wilting of the affected parts, followed by dying, 

 which begins at the tips of the younger shoots and works downward. The 

 older parts of the plants are not immediately killed but may persist for some 

 time after being attacked by the fungus. 



The cause of the disease is said to be Glomerella rufomaculans, the cause 

 of the bitter rot of the apple. Inoculation experiments confirmedj this 

 conclusion. 



While studying this disease the author thought it desirable to determine 

 whether other species of Glceosporium could produce an anthracnose of the 

 sweet pea similar to that caused, by the bitter rot organism of the apple, and 

 inoculations were made with 5 different Glceosporiums taken from the May 

 apple fruit, oak galls, sassafras leaves, Persea, and guavas. The Glceosporium 

 from the May apple and from the oak gall were successful with puncture 

 inoculations, and that from the sassafras leaves with atomizer inoculations as 

 well as with puncture inoculations. No infection followed attempts to inocu- 

 late with the Glceosporium from Persea or from the guava. 



Until perfect stages of these fungi are found, it is not thought possible to 

 determine definitely the relation of all these species, although there is a 

 possibility that the species occurring on the May apple, oak gall, and sassafras 

 are the same as that reported, upon as causing the bitter rot of the apple. 



Heart rot of Quercus nigra, H. D. House (Mycologia, 3 (1911), No. 4, P- 205; 

 Internat. Inst. Agr. [Rome], Bui. Bur. Agr. Intel, and Plant Diseases, 2 (1911), 

 No. 7, p. 1800). — A brief note is given of the occurrence on living trunks of 

 Q. nigra of the fungus Pijropolijporus ealhinsii. This species is believed to cause 

 heart rot similar to that due to P. igniarius, and the extension of range and 

 discovery of a new host is believed to be of value to the forest pathologist. 



