MICRO-ORGANISMS IN SOME PLANT DISEASES 307 



Pleuro-Pneumonia. 



This disease of cattle is at the present time practically 

 non-existent in this country, owing to the vigour with 

 which the stamping-out system has been carried out. 



In a few cases pleuro-pneumonia was discovered in cattle 

 imported from abroad, some of which were suspected before 

 the animals were slaughtered. The lungs in an affected 

 animal present a peculiar marbled appearance. Various 

 organisms have been described in this disease, but at 

 present no baciUus is admitted on all hands as the specific 

 cause. 



MICRO-ORGANISMS IN SOME PLANT DISEASES. 



Dr. Y. Peglion describes in Malpighia (1896, p. 556) a 

 disease which attacks the stem of the hemp, causing disin- 

 tegration of the tissues. It appears to be produced by an 

 organism of the nature of a bacillus embedded in mucilage, 

 and closely resembling B. cuboniana, a parasite of the 

 mulberry. In Bulletin No. 12, for 1896, of the Division 

 of Vegetable Physiology of the U.S. Department of Agri- 

 culture, Mr. E. F. Smith states that several species of 

 solanacese — the potato, the tomato, and the egg-plant, 

 Solanum Tnelongena — are attacked by a disease which he 

 calls ' brown-rot,' due to a hitherto undescribed parasite, 

 which he names Bacillus solanacearwm. It closely resembles 

 B. tracheiphilus and the form known as ' Kramer's 

 bacillus,' but differs in several characters from both. In 

 the Revue Mycologique for 1896, M. E. Roze has described 

 several bacteria which cause diseases in the cultivated 

 potato, viz., Micrococcus nuclei, M. imperatoris, M. pellu- 

 cidus, always found associated with the ' scab,' M. albidus, 

 and M. fiavidus. 



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