pucciNiA. 353 



Iceland, Greenland, and Switzerland. Juel states tliat this is the only 

 heteroecious Puccinia whose uredo- and teleutospores inhabit a dicotyle- 

 donous plant. 



{2) Accidia are absent ; pycnidia, urcdospores, and teleutospores 

 developed on the same plant. {Brachypuccinia, Schroet.) : 



Puccinia suaveolens (Pers.) (Britain and U.S. America). 

 One tuiiii on Cirsunii arvense, and a second on Centaurea Ci/ani/s. 

 Pycnidia and uredospores appear first, then teleutospores develop 

 amongst the later-formed uredospores. 



The shoots and leaves of attacked plants are permeated with 

 mycelium and rendered conspicuous by their elongated shape, 

 lighter colour, and smaller, less lobed, softer leaves (Fig. 186). 

 Diseased plants bear no flowers. Wakker on investigating the 

 diseased stems found : non-development of those sclerenchyma- 

 sheaths of the primary tissues situated towards the interior of 

 the stem, whereas those towards the outer side show secondary 

 thickening ; irregularities occur in the interfascicular cambium, 

 so that the phloem becomes abnormally developed and propor- 

 tionately more extensive than the wood, it may also be divided 

 by a band of sclerenchyma. 



P. hieracii (Schuni.) (Britain and U.S. America). On numerous Com- 

 positae, e.g. Carlina, Cirsium, CardtmSy Centaurea, Leontodon, Scorzonera, 

 Crepis, Hieracium, Cichorium, etc. 



Plowright distinguishes tw(j allied species on Compositae, \'v/.. P. 

 centaureue, Mart, on Centaurea nigra, and P. tarcLvacI Plowr. 



P. bullata (Pers.) (Britain and U.S. America). On Umbelliferae, e.g. 

 Apium, Petroselinum, yEthiisa, Selinum, Conium, Anetkxm, etc. On culti- 

 vated species (e.g. Parsley, Dill, Celery, etc.) it may prove troublesome.' 



P. oreoselini (Strauss). On Peucedanum and Heseli. (U.S. America.) 



P. helvetica Schroet. On Asperula taurina. 



(3) Uredospores and teleutospores alone known. The related 

 pijenidia and aecidia have either not as yet been traced, or do 

 not e.ii<if. (irr/iiipi/rrinia, Sehroct.): 



Puccinia sorghi Schwein. {Puce, maydis lier.). This rust of 

 ^Sorghum and Zca Mais occurs in America, Italy, Germany, etc. 

 The leaves become more or less beset with little pustules, in 

 which the sori of uredospores or teleutospores are contained 

 (Fig. 187-189). 



P. purpurea C'ke. On Sorghum vulgare in India, and Zea in Africa. 



'Description and figures in A". J. A'jric. Expar. Station Report, 1801. 

 Z 



