1899.] PUBLIC DOCUMENT — No. 33. 153 



this might bo identical with the violet disease. This, how- 

 ever, did not prove to be the case. Examination showed 

 that the cause of the trouble was a fungus, but one of quite 

 a different nature from Oercospora, and belonging to the 

 genua Colletotrichum, being apparently a new and unde- 

 scribed species. This form has therefore been described in 

 the "Botanical Gazette" of March, 1899, under the name 

 Colletotrichum Violce — tricolor is. 



This same disease has been seen in a few other localities 

 in the State, and Prof. B. 1). Halsted has also very kindly 

 sent us specimens of it from New Jersey, so that the trouble 

 is doubtless widespread. Its occurrence, however, seems to 

 have been comparatively slight, except in the one instance 

 described above. In this case the number of plants was 

 very large, and pansies had been grown upon the same field 

 for several years, which may account for the severe outbreak 

 of the disease. 



A portion of this field was sprayed twice with strong 

 Bordeaux mixture ; but, as it was already late in the season, 

 and heavy rains prevailed at the time, little success from the 

 treatment was looked for. The owner, however, thought 

 that a beneficial result appeared from the treatment, and 

 from our own observation we can claim at least that later in 

 the season the sprayed portion of the field was certainly in 

 the best condition of any. If this did indeed result from 

 the spraying under such adverse conditions, it seems likely 

 that the disease could be kept well in check by proper treat- 

 ment. 



Physiological Disorders. 



Seasonal Peculiarities of Certain Shade Trees. 



Some complaints have been made in regard to the falling 

 of leaves on the elm, maple and apple trees. This was 

 especially noticeable on the elm in various sections. "We 

 had many specimens sent in for examination, and our at- 

 tention was called to a number of trees in which certain 

 branches had only half-developed leaves on them. These 

 leaves would linger along a while in this condition, when 

 they would gradually turn yellow and drop to the ground. 



