386 Lecture on the Parasitic Funcji of the British Farm. 



of any other name, I am obliged to announce by its botanical one, 

 clados-porium herharum, the character of its growth being, as you 

 see in Fig. 6, totally unlike mildew. It grows on old leather as 



Cladosporium Herbarura, magnified highly. 



well as on wheat. The dissimilarity to Pucciniais visible enough. 

 Spores may be seen here in their cases. The common appear- 

 ance on the straw, as shown in Fig. 7, not being accurately ob- 



Fi-. 7. 



Common appearance of Cladosporium an Straw, slightly magnified. 



served, misleads. Though I have no other name but the botanical 

 one by which to call it, I can trace its derivation to the Greek 

 ^^(x^^os, a branch, because the spores grow on minute branches. 

 Whatever tends to preserve the health of the wheat will prevent 

 also the attacks of this fungus. 



(2.) We now come to other minute parasitic yz^/z^-z of corn- 

 plants. They are called urediiies, the plural of uredo, from the 

 Latin uro, to burn, on account of the scorched appearance of the 

 parts on which they vegetate. Different parts aie attacked by 

 different species : the uredo of the maize alone growing every- 

 where except on the roots. The first uredo I shall notice is 

 known familiarly to the farmer as rust, red-rag, red-rohin, red- 

 gum, and comes out in yellow or orange blotches on the stem, the 

 leaf, and the chaff- scales, appearing as a powder. The hue of a 

 whole field is often affected by it, and fears naturally arise, but 

 it frequently happens that a few days bright sunshine dissipates 

 the fungus ; but mischief has been done, and the crop feels it. It 

 is called uredo rid)igo, and under the microscope the sjwres appear 



