18 



THE BLADE. 



Some le!if-l)la(los,as tlioso of 

 PaiiicHtii Crns-tjalU (barn- 

 yard' ^rass), /'. pi i cat III)), 

 many Ki)ecies <»f Sorghum, 

 taper each way, and are lin- 

 ear lanceolate, l)ut they have 

 us many bundles at the base 

 us in the middle. They are 

 like Fig. 8, only in disguise. 



Transverse veins arc vis- 

 ible to tlie eye in Pnnicum 

 CrnsfjalU, Cliloris, Bamhiisa 

 (bami)oo),and in most others 

 they are found to a greater 

 or less extent, but they are 

 not often conspicuous. 



Fio. 8.— Leaf-blade of Aruniln dnnax, in which 

 the flhro-vasfiUar buiidlus, one after auotlier, 

 leave the mid-rib for the blade, and those alonn 

 the niar^in terminate before reaching the apex. 

 — (Duval-. louve.) 



Fi(i 12. -Parallel veined leaf of I'<m triviali.-<. - 

 (Diival-.loiive.) 



Fid. 13.— Leaf-blade of Pauicum Crux-gnlU 

 (barn-yard Krassi, tai)erintf each way from the 

 middle.— ( Duval-.l'iu\e. i 



Some leaves are quite firm and remain p„, u.-cmss sections of a 



,- , •111 large mid-rib of the leaf of 



green all winter, even with COnsulcral)le Xiznninatinntiva; <i, near the 



base; It, farther np near the 



cold and e.vposure, while Otliers witll a nii<ldlt': ^ still nearer the 

 '■ ape.x, where most of the bun- 



little protection, will remain green for a bbe.^Txfl.Tsmtorth).'''^ 

 whole year. Most annual grasses and some perennials are very 

 sensitive and (juickly perish and fade on the approach of a frost. 

 Some grasses will make growth at a low temperature, and start 



