said that better results have been attained by sowing the telio- 

 spores from the cedars upon the malaceous plants as trial hosts 

 and making observations for the appearance of the aecial genera- 

 tion rather than the converse. The reason for this lies in the dif- 

 ferent nature of the telial and aecial phases. The teliospores are 

 mature in spring and germinate at once. Following an inoculation 

 from teliospores the first sign of infection, the pycnial stage, is to be 

 expected in six to twelve days, while the second sign, the aecial 

 stage, may be looked for in one to four months, the actual time 

 varying with the different species. In this way the cultures are 

 carried on during the normal growing season and results obtained 

 before the close of the season. The converse cultures in which the 

 aeciospores are sown upon the cedars require a much longer in- 

 cubation period, at least through one winter season, and possibly 

 through two in some species. This latter method being more 

 tedious and less likely to result in infection is not so satisfactory 

 for working out life-cycles, and yet it may have certain advantages 

 that will be mentioned later. 



It is possible to carry on cultures out-of-doors but owing to 

 the many disturbing factors such as danger from outside infection, 

 accidental destruction of the trial host and many others the writer 

 has practically abandoned them in favor of indoor cultures. For 

 indoor experiments small but vigorous growing potted plants are 

 most desirable. Some of the earlier investigators used cut branches 

 with the ends placed in water, and detached leaves in moist 

 chambers, but it is impossible to keep these in fresh condition for 

 a sufficiently long time. The use of rooted plants which must be 

 kept growing vigorously in pots for several months makes it neces- 

 sary to carry on the work in a greenhouse, the conditions being too 

 unfavorable and artificial for vigorous growth except under glass. 



In making the inoculations the writer now employs the method 

 of suspending a portion of the branch or the gall bearing the telia 

 over the trial host in such a manner that the basidiospores (spo- 

 ridia) will fall naturally upon the desired area, either young leaves 

 or shoots, or developing fruit, according to whether the form is sup- 

 posed to be chiefly foliicolous, caulicolous, or fruiticolous. The 

 whole is then sprayed thoroughly with a fine spray from an atomizer. 

 Care is taken to thoroughly moisten the telia. Sometimes the 

 twig or branch bearing them is immersed in water and allowed to 

 remain a few moments, all excess water being taken off before 



