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keep us too long away from our campus wanderings. Rust of 

 violets is good material for work upon reproduction (50) and 

 Wheaton has an abundant supply. Viola fimbriatula blooms in 

 April and along with its deep blue blossoms the spermatia and 

 aecidiospores of rust make gay yellow spots on its leaves. The 

 familiar, long-stemmed, blue violet follows with plenty of rust. 

 Although building alterations destroyed a choice plot there are 

 still rusted specimens in the rock garden. The little white violet 

 of the woods is also host to the rust. It is upon leaves of this 

 white violet that we are most apt to find the black teleutospore 

 clusters in the fall. Thus we complete the cycle of violet rust. 

 In May a rust appears wherever dewberry trails over fields, 

 across footpaths, or along roadsides. Its unfolding leaves are 

 covered with a crust or caeoma of aecidiospores. This rust, 

 Caeoma nitens, introduces still another problem. Its aecidio- 

 spores should reinfect dewberry and later, teleutospores from 

 that generation should complete the cycle. Kunkel in a series 

 of germination studies, where he watched under the microscope 

 the germination of spores in drops of various nutrients, dis- 

 covered that some of the aecidiospores of Caeoma nitens acted 

 like teleutospores. These spores sent out a four-celled filament 

 and formed the characteristic four spores by which a teleuto- 

 spore starts a new rust generation. (41) Here is seen the sci- 

 entist's "deep insatiable curiosity about the things of nature." 

 (39) Kunkel examined spores of Caeoma nitens gathered from 

 New Hampshire to Virginia and discovered a short-cycle and a 

 long-cycle race. The decisive character is the habit of the 

 germinating aecidiospores but he found also a slight difference 

 in size and shape of the spores and a color difference. The spores 

 of the short-cycle race match Cadmium orange; those of the 

 long-cycle, Xanthine yellow. One may check ones color-sensi- 

 tiveness to yellows by matching leaves of rusted dewberry and 

 then verify the rust strain by sowing the spores in drops of 

 water and watching their germination. There is, of course, a 

 phylological interest here. Which is the primitive race? Kunkel 

 thinks the short-cycle one the primitive and the one with an 

 extra spore form the derivative. (42) Caeoma nitens is appar- 

 ently trying out experiments. Pady reports that in new infec- 

 tions of blackberry canes the rust grows through the host cells 

 instead of between the cells as is usual for a rust. It develops 



