122 MICEOSCOPIC FUNGI. 



Of the six species of tliis genus known to occur 

 in Great Britain_, the majority may be commonly 

 met with. That very widely- diffused plant_, the 

 wood cow-wheat [Melampjrum i:)ratense), known 

 well to all amateur botanists for its pertinacity in 

 drying black, and presenting anything but an 

 inviting appearance to claim for it a place in the 

 herbarium — also becomes the matrix for the de- 

 velopment of a member of this genus ; i.e., the 

 cow-wheat rust {Goleosporlum Rhinmithacearum, 

 Lev.), and which is found on other allied plants, 

 as the Httle eyebright {EuiDlirasia officinalis), &c. 

 (plate YIII. fig. 176). In colour and habit it 

 resembles the last-named species, and its free, 

 echinulate spores (plate VIII. fig. 177) form a 

 pretty object for the microscope. 



Another equally common species is found inhabit- 

 ing the leaves of the sow-thistles {8onchus arvensis 

 and S. oleraceus), and in the autumn may generally 

 be found on either of those plants, presenting the 

 appearance delineated in our plate (plate VIII. 

 fig. 178). The permanent spores resemble in many 

 l^oints those of the first species, as will be seen 

 from the figure from De Bary^s treatise on this 

 subject (plate VIII. fig. 179). This is certainly one 

 of the most showy of uredinous fungi, and could 

 not be well overlooked. 



The butter-bur rust {Coleosjoorium petasites, Lev.) 

 and the Campanula rust {Coleosporiiim GamvanuJce, 

 Lev.) are found, the former on the leaves of the 



