“BACTERIOSIS” OF CARNATIONS.’ 
ALBERT F. Woops. 
DurinG the past two or three years the writer has had under 
investigation a disease of the Bermuda, or Easter lily. Early in 
the course of this work it was observed that the disease of the 
lily possessed certain characteristics in common with one affect- 
ing carnations, first described by Dr. J. C. Arthur in a paper’ 
read at a meeting of this association at Toronto, August 1889. 
Through this paper and the publications of Dr. Arthur3 and of 
Arthur and Bolley,‘the disease has come to be generally known 
as ‘“‘bacteriosis” of carnations. In connection with the work on 
the lily disease,’ ‘‘bacteriosis” of carnations has received con- 
siderable attention during the past year, and the object of this 
paper is to review briefly some of the results obtained. 
Fora general description of the disease the following, quoted 
from the bulletin by Arthur and Bolley already cited, covers the 
ground thoroughly : 
Bacteriosis is a disease of the carnation leaf, rarely attacking the stem or 
other parts of the plant. It generally starts in the leaf when immature, and 
is best diagnosed in the younger but full-sized leaves nearest the upper end 
of the stem. Taking such a leaf, which on its surface presents no unusual 
appearance to the eye, and holding it toward strong light, small, pellucid 
dots may be detected scattered irregularly through the leaf, sometimes having 
a faint yellowish color, which are the centers of infection. The appearance 
of the dots has a close resemblance to those of the oil glands in the leaves of 
the common St. John’s wort (Hypericum perforatum), a rather abundant weed 
* Read at the meeting of the Amer. Ass’n Adv. Sci., Detroit, Mich., August 1897- 
2J. C. ARTHUR, Proc. Amer. Ass’n Adv. Sci. 38 : 280. 18809. 
3J. C. ARTHUR, Amer. Florist 6: 419. 1891; Rep’t Amer. aie Soc. 52. 
1892; Rep’t Amer. Carnation Soc. 12. 1894; Amer. Florist 9: 467. 1 
‘ARTHUR and BOLLEY, Purdue Univ. Agr. Exp. Sta. Bull. no. i ” ath pl. 8. 
5 The lily disease has been fully discussed in a bulletin soon to be issued by the 
Division of Vegetable Physiology and Pathology, U. S. Department of Agriculture. 
200 [SEPTEMBER 
