318 



INTRODUCTION TO CRYPTOGAMIC BOTANY. 



victims, than the oats, and wheat, and barley, and rye, of tem- 

 perate realms. Though, however, they reduce materially the 

 returns of our cornfields, they do not appear to be directly 

 destructive to life like the Ergot. Bunted wheat often forms a 

 very large proportion in flour, and is used more especially for 

 the manufacture of gingerbread, in which the colour is not of 

 much consequence, and the flavour is concealed. In any case, 

 however, it seems to be eaten with impunity. It is said that 

 in reed-beds, where the stems are affected with Ustilago 

 Typlioides, the workmen suffer from headache and other bad 

 symptoms, in consequence of inhaling the abundant spores. 



Fi^. 72. 



a. Sartvellia foveolata., Berk, and Curt. Spores magnified. From a 

 Surinam specimen, from the Scliweinitzian collection. 



b. Spore of Tilletia caries, germinating and producing spores of a 

 second order at the tip of the thread. 



c. Spores of the second order seen separately. The two figures are 

 from my Memoir in the Journal of the Hort. Soc. of London, vol. ii., 

 p. 113, 1847. 



d. Spore of the third order, arising from germination of spore of 

 second order. 



e. Spore of third order germinating. 



/. Ditto, producing spore of fourth order. The last three figures are 

 from Tulasne's Memoir in Ann. d. Sc. Nat, 4 ser., vol. ii. 



