32 



THE JOURNAL OF PHARMACOLOGY. 



Corn-husk, 



Rye-straw, 



Esparto-straw, 



Barley-straw, 



Wheat-straw, 



Oat-straw, 



108-252 mikra'Jong and 36-90 mikra broad. 



86-345 



28- 88 



103-224 



152-449 



186-448 



10-16 

 7-19 

 12-14 

 18-24 

 12-17 



( ( 



Oat, rye and wheat-straws have rectangular epidermal cells. In the 

 case of rye-straw the side walls are markedly wavy, in that of wheat-straw 

 almost straight, and ; in oat-straw somewhat wavy. Barley-straw has 

 more irregular, almost rhomboidal epidermal cell walls. Entirely irreg- 



FiG. 4. Com Husk and Stalk Paper.— Par., Parenchyma, thin-walled and thick-walled ; Epi , Epi- 

 dermal Cells ; M. R. , Irregular Stone Cell ; P. V., Pitted Vessel ; Fib , Bast Fibers ; ,.,; joo diam. 



ular, and>ery broad and strong-walled epidermal cells occur in corn-husk 

 paper. They often form large groups, occupying a space up to i mm. 



square. . ., , n 



,;, Rice-straw possesses very narrow fibers (mostly 7 mikra in width), and 



narrow, relatively very long epidermal cells with strikingly thick outer 

 walls, which exhibit wart-like thickenings. The Chinese rice-papers 

 (mostly tapestry papers) are often sized with starch-paste and usually con- 

 tain parenchymatic cells with remnants of starchy contents. 



5. Esparto-paper, on microscopical examination, is readily recognized as 

 belonging to the straw papers. It is quickly told from the ordinary va- 

 rieties of the latter by its peculiar epidermal cells (Fig. 4). 



