BY D. McALPINE. 453 



etc. — Puccinia pruni-spinoscE, Pers.," and have incorporated some 

 of his references in the literature of the sul)ject. There are 

 several points in it worthy of comment, as showing the different 

 behaviour of the same fungus under different conditions of 

 existence. After noting that the fungus has been described 

 under several different names, he remarks : — " Some confusion 

 has probably arisen from the fact that the uredo stage alone 

 occurs upon the peach and from the resemblance of the uredo- 

 spores to the teleutospores of Uromyces.^'' Both the uredo-stage 

 and teleuto-stage, as we have seen, occur upon the peach in 

 Australia, nevertheless the latter is comparativeh^ rare and has 

 undoubtedly led to misunderstanding of the true nature of the 

 fungus from the absence of two-celled teleutospores. The uredo- 

 spores are certainl}^ suggestive of Uromyces on a superficial view, 

 but their germination, not by a single apical pore, but by a l^and 

 behind the apex, excludes the idea. 



Again he states : — " The uredospores may or may not be present 

 on the plum, but on the specimens examined a few have been 

 found in all cases mingled with the teleutospores." In specimens 

 of plum leaves described by me in Bulletin xiv. of the Victorian 

 Department of Agriculture in ]March, 1891, only uredospores were 

 present at that time, while on specimens examined by Professor 

 De Bary only teleutospores were present and no uredospores. 



Again he remarks : — " Teleutospores have never yet been found 

 upon the peach, and it is probable that they do not occur upon it 

 at all, since specimens gathered in Texas as late as December 26th 

 failed to show any." 



It is rather a strange and striking fact that teleutospores 

 which are commonly regarded as winter spores should occur upon 

 the peach in a climate such as ours und not in America. 



To show the thorough agreement between American specimens 

 of Fnccini'i pruiii, Pers., and Australian so-called Uromyces 

 amygdali, Cooke, I have reproduced some of Professor Scribner's 

 drawings for comparison (fig. 14). They prove conclusively the 

 identity of the two forms and disprove, if such were needed, and 

 in spite of Dr. Cooke's pertinacity, the Uromyces-character of 



