1889.] DEPARTMENT OF BOTANY. 47 



of spores. On the leaves of a few of the Russian pears on the College 

 grounds, particularly on those of the Bessmanka pear. I found this eruption 



had taken place without producing the brown spot. I believe that mo-t of 

 the Russian varieties, on account of having thicker leaves than those origin- 

 ating in southwestern Europe, will prove to be much less affected by this 

 disease. 



Other species of the genus Pyrus are also infested by a fungus, that to all 

 -appearances is the same thing. Many of the quinces brought into our 

 market this fall from the East were almost completely covered with this 

 destructive parasite. This fungus seems to be identical with that on the 

 pear. Some apple seedlings on the ground, growing pearfeedlings, were 

 found to be quite seriously attacked by it. 



The fungus is carried over winter not only by the winter spores which are 

 produced late in the fall and winter, but also by summer spores, if they suc- 

 ceed in finding lodgement in the buds of next year's growth. Concerning 

 its prevention and destruction nothing very definite can as yet be said, since 

 practical experiments have only been begun. 



A number of the leading nurserymen of this country claim that seedlings 

 are much less liable to be attacked if planted in a new soil, or at least soil 

 which has not been occupied by trees. 



Barry recommends that the ground be prepared by sub-soil plowing to a 

 depth of two feet the preceding autumn, and also by a liberal application of a 

 compost of lime and leaf mold to be well plowed the following spring, the 

 object being to secure a vigorous growth as early as possible in the season, 

 in order that the young trees may be better able to stand attack. All dis- 

 eased leaves should be raked up as soon as they fall, and burned. 



Prof. Galloway has been highly successful during the past season in pre- 

 venting the disease, by the application of a mixture of copper, lime and 

 water, in the following proportions: Copper sulphate, six pounds; lime, six 

 pounds; water, twenty-two gallons. A block of five thousand pear trees, 

 treated at intervals of ten days, beginning June 5th, were reported August 

 11th as being nearly free from the fungus. At the same time another block 

 of young pear trees adjoining these were very severely injured by the fungus. 



THE SEED (OATS OF CROTALARIA SAGITTALIS AND ASTRAGALUS MOLLISSIML'S. 



The subject of Crotalism and Loco-poisoning has attracted considerable 

 attention in late years. It is sufficiently important to demand a short place 

 in this report. One of the veterinary students, Mr. Ash worth, has studied 

 the seed coats of Crotalaria sagittalis and Astragalus mollissimiis for the 

 purpose of obtaining some characters to aid in the diagnosis of these diseases, 

 especially after parts of the seed have passed through the alimentary canal. 



Crotalaria sagittalis, L., or Rattle-box, is an annual common in the west- 

 ern part of the State, along the Missouri river. It has a rather wide distribu- 

 tion in the United States, occurring in sandy soil from Massachusetts to 

 Illinois, Missouri, Iowa, Nebraska, and south to Texas. Astragalus mollis- 

 simus, one of the Loco plants, is a perennial and occurs on high sandy soil, 

 distributed throughout the plains and table-land- of Colorado, New Mexico, 

 Utah, Wyoming. Texas, Indian Territory and Arkansas. In Astragalus 



