AMERICAN UREDINE^E. 173 



one or more of the others in much less abundance, either 

 just beginning to appear, or nearly vanished. 



Still another sort of spore sometimes occurs among 

 grass-forms that has had special attention called to it lately 

 by the researches of M. A. Carleton, until now only 

 partially published (Science 13:250). It has long been 

 recognized in Puccinia vexans Farl., and considered to be 

 a peculiar teleutospore-like uredospore : but Carleton 

 finds that it has, moreover, a peculiar manner of germina- 

 tion. He has given the name amphispore to it. We have 

 ventured to apply the name to what has heretofore been 

 called the uredospore of Puccinia tripsaci, both on account 

 of the structure and texture, and of the association with 

 the other spore-forms. But this assignment of its role 

 must be accepted as somewhat tentative until opportunity is 

 given for studying the mode of germination, which is at 

 present unknown. 



In this article we have extended and varied the use of 

 signs for designating spore stages of the Uredinece. For 

 some time the Roman numerals, I, II, III, have been 

 generally employed to indicate secidial, uredo, and 

 teleutosporic stages, respectively, and occasionally of late 

 the spermogonial stage has been represented by O. To 

 these we now add X for the amphisporal stage. When 

 these signs are used in connection with specimens of 

 Exsiccates^ we have found it convenient to indicate the 

 relative abundance of each stage by using capital forms for 

 the dominant stages and lower case forms for deficient 

 stages: thus ii, iii, X applied to a specimen of Ex sicca tec , 

 means that it exhibits chiefly amphisporic sori, but that 

 some more or less perfect sori of uredospores and teleuto- 

 spores are present, or at least that some spores of these 

 may be found by moderate search among the amphisori. 



The first article of this series contained descriptions of 

 species numbered from one to seventeen, the second 

 article contained numbers eighteen to thirty-four, and the 

 present article contains numbers thirty-five to forty-four. 



