246 



INTRODUCTION TO THE STUDY OF FUNGI 



developed on Berberis vulgaris, but no corresponding uredo- 

 spores or teleutospores upon that plant, and therefore they 

 have to be sought elsewhere (Fig. 117). 

 On the other hand, the uredospores and 

 teleutospores of Puccinia graminis nourish 

 on wheat and other grasses, whilst no 

 spermogonia or aecidia have been known to 

 infest the latter plants. Hence it is con- 

 cluded that the above form the normal series, 

 with the spermogonia and aecidia on the 

 berberry, and the uredospores and teleuto- 

 spores on wheat, which completes the cycle. 

 LV-^/ J This theory is supported by the contention 

 hV^- ' that the germinating spores of Aecidium 



berberidis are capable of producing Puccinia 

 Fia. 117.— Aecidiospore graminis by artificial inoculation on wheat; 



in germination. After n . . . „ 



Tll ] aane and conversely the promycelial spores 01 



Puccinia graminis (Fig 118) may be used 

 to inoculate the leaves of the berberry, and produce thereon 

 Aecidium berberidis. This is the theory and its application, 

 which we will here leave as it 

 stands. In another group, the 

 Brachy - pucciniae, spermogonia, 

 uredospores, and teleutospores are 

 found on the same species of plant, 

 but the aecidia are unknown. To 

 this succeeds the Hemi-puccinia, 

 in which uredospores and teleuto- 

 spores occur on the same plant, 

 but the spermogonia and aecidia 

 are unknown. It is here that the 

 sceptics would place Puccinia 

 graminis were they not debarred Fl0 . lli ._ Pw!BMa teleutospore 



by the anathemas of the votaries germinating and producing pro- 

 j, TT , . TT -. j. ■,, mycelial spores. After Tulasne. 



or Heteroecism. Hereafter follows 



the group Pucciniopsis, in which spermogonia, aecidia, and 

 teleutospores have been recognised, but not uredospores, so 

 that in this group of species the uredo stage is deficient. 

 Of the two remaining groups, Micro-pucciniae includes those 



