REED: SPECIALIZATION OF PARASITIC FUNGI 365 



1. Thymi-Stipae Kleb.; aecidial stage on Thymus serpyphyllum, T. 



angiistifolius and T. vulgaris. 



2. Salviae-Stipae Kleb.; aecidial stage on Salvia silvestris and S. 



pratensis. 

 Puccinia sessilis Schneid. This rust, which has its uredo and 

 teleuto stages on Phalaris arundinacea and its aecidial stage on various 

 plants of the Liliaceae, Amaryllidaceae, Araceae and Orchidaceae, has 

 been broken up into a number of distinct species, based largely upon 

 the choice of the aecidial host. Klebahn (77-83, 86, 87, 89-91) has 

 carried out the cultural tests with the rust and recognizes the following 

 relations: 



1. Puccinia Smilacearum-Digraphidis (Sopp.) Kleb. 



a. Smilacearum-Digraphidis typica Kleb.; aecidial stage on Con- 

 vallaria majalis, Maianthemum hifolium, Polygonatum 

 multiflorum, P. officinale, P. verticillatum and Paris qiiadri- 

 folia. 



h. Convallariae-Digraphidis (Sopp.) Kleb.; aecidial stage on 

 Convallaria majalis. 



c. Paridi-Digraphidis (Plowr.) Kleb.; aecidial stage on Paris 

 quadrifolia. 



2. Puccinia Allii-Phalaridis Kleb.; aecidial stage on Allium ursinum. 



3. Puccinia Orchidearum-Phalaridis Kleb.; aecidial stage on Gymna- 



denia conopea, Listera ovata, Orchis maculata, 0. latifolia, 

 Platanthera bifolia and P. Chlorantha. 



4. Puccinia Ari-Phalaridis (Plowr.) Kleb.; aecidial stage on Arum 



maculatum. 



5. Puccinia Schmidtiana Diet.; aecidial stage on Leucojum aestivum 



and L. vernum. 



It may be especially noted that, according to Klebahn, Puccinia 

 Smilacearum-Digraphidis includes a race which occurs on a number of 

 hosts and two races which occur on only one host. The hosts for the 

 second two races are also hosts for the first race. It is further to be 

 noted that the species recognized are also to be distinguished on the 

 basis of host relations. 



Puccinia Caricis (Schum.) Rebent. Klebahn (91) indicates the 

 following specialization in the Urtica-Carex rust, the races being indi- 

 cated by the choice of urecfo and teleuto host: 



1. Urticae-acutae on Carex acuta, C. Goodenoughii, to a less extent C. 



stricta. 



2. Urticae-hirtae on Carex hirta. 



3. Urticae-acutiformis on Carex aciitiformis, C. Kochiana, to a less 



extent on C. pseudocyperiis. 



4. Urticae-vesicariae on Carex vesicaria. 



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