BASIDIOMYCETES. 



151 



FIG. 148. GymnospoTangium, sabince. A 

 small portion of the epidermis of a Pear- 

 leaf (a) pierced at b by the germinating 

 basidiospore (c). 



teleutospores are small ; they contain parapbyses, and are for a long time 



covered by the epidermis. P. coronata, on Oats and Eye Grass ; its tecidia on 



Rhamnus ; the teleutospores are surmounted by a crown "coronate processes." 



P. phragmitis, on Reeds ; ascidia on species of Rumex and Rheum. P. molinice, 



on Molinia ccendea ; the aecidia on 



Orchids. P. poarum, on Meadow- 



Grass ; aecidia on Tussilago. Various 



Pucciuias growing on species of Cares 



have their fecidia on Urtica, Lysi- 



machia, Cirsium, Pedicularis, etc. 



Of those AUTCECIOUS species, which 



have all their generations on the 



same host, may be noted : P. galli, 



P. meuthce, P. viola;, P. epilobii, P. 



asparagi, which grow on the hosts 



from which they have taken their 



specific names. As representative 



of a group which have spermogonia, 



uredo- and teleuto-sporeson the same 



host, but on different individuals, P. 



suaveolens, on the Field-Thistle, 



may be mentioned. The spermogonia have a strong odour. A peculiar group 



(Leptopuccinia) has only teleutospores, which germinate immediately, and 



whilst still attached to their living host. To this group belong P. arenarice, 



on a number of Caryophyllaceaa ; and P. malvacearum, on various Malvaceae, 



introduced iu 1873 from South America to Europe, where it soon proved very 



destructive to Hollyhocks. 



Uromyces (Fig. 149) differs only from Puccinia in always having unicellular 

 teleutospores. Among this genus both hetercecious and autcecious species are 

 found. To the first group belong U. pisi, whose aacidia are found on Euphorbia 

 cyparissias, and U. dactylidis, whose aecidia appear on Ranunculus ; to the 

 second group belong U. beta, U. pliaseoli, U. tiifolii. 



Triphraginium has teleutospores with three cells (one below and two above), 

 on Spircea ulmaria. 



Phragmidium (Fig. 150) has teleutospores consisting of a row of cells (3-10) 

 arranged in a straight line ; the upper cell has one 

 germ-pore and the others four germ-pores placed 

 equatorially. Both this and the preceding genus 

 have large, irregular aacidia without peridia, but often 

 with bent, club-like paraphyses (150 b and c) ; they 

 are all autcecious. and are only found on the Eosaceaa. 



Endophyllum (see above, under teleutospores, p. 

 147) on species of Semperrivum. 



Gymnosporangium (Figs. 152, 154) has bicellular 

 teleutospores collected in large, gelatinous masses 

 formed by the swelling of the long spore-stalks ; in each cell 2-4 germ-pores are 

 found. Uredospores are wanting. All the species are hetercecious ; the teleuto- 

 spores appear on Junipcrus, the aacidia (Rccstelia) on the Pomaceae. G. sabince, 



FIG. 149. Uromyces 

 genista ; a uredospore ; b 

 teleutospore. 



