112 MICROSCOPIC FUNGI. 



remains of tlie ruptured epidermis. The spores are- 

 globose and brown (plate VII. fig. 139). We have 

 not met with any other UrecUne on the sorrel 

 leaves, though one having a similar appearanca 

 to the naked eye is not uncommon on several 

 species of dock. 



The fern rust {TJredo Filicum), which occurs on 

 the under surface of the fronds of two or three 

 species of ferns, we have never met with, and do not 

 think that it can be considered common. It has 

 been found in the West of England, on Cystopterisy 

 and Sowerby collected it, probably not very far 

 from London. 



One of the most common is the rust found on 

 the leaves of the enchanter^s nightshade {Circcea 

 lutetiana), sometimes nearly covering the under sur- 

 face with its tawny snuff-coloured spores (plate YII. 

 fig. 135). The plant on which it is found is rather 

 local, but the rust {Uredo Circcece) seems to abound 

 wherever the plant on which it is parasitic flourishes. 

 Another fungus of a very similar external appear- 

 ance may be collected, more rarely, from the leaves 

 of the same plant ; but in this the spores are two- 

 celled, or divided by a transverse partition. This 

 fact is mentioned to guard against disappointment, 

 should the spores be found to differ from the 

 characters of this section, and to show that the 

 microscope is essential to the study of fungi. The 

 spores of the true Uredo are globose and without 

 any partition (plate VII. fig. 136). 



