THE JOURNAL OF PHARMACOLOGY. 31 



of cuticle that remain after the fiber has been treated with sulphuric acid 

 are so characteristic that cotton can always be made out with certainty, 

 even if it exists in the paper in a much demolished condition. The cell- 

 wall is often swollen, but it never shows knotty swellings, such as are seen 

 in hemp and flax. 



4. Straw. — Straw from wheat, rye, oats, rice and corn is readily recog- 

 nized in paper by the fact that in addition to its rather characteristic fibers 

 it also contains other well marked elements. These are bundles of vessels, 

 mostly thin, [spiral or reticulated, or portions of same (fragments of spirally 

 thickened vessels, single rings, etc.). Further, large, empty parenchy- 

 matic cells which are usually thin-walled and short, with rounded corners. 

 Some, however, are long. In the latter case up to 33 mikra broad, and 

 often thickened with pore-like markings. Thirdly, much-thickened 

 sclerotic epidermal cells. These are highly characteristic in form, and en- 

 able one to recognize at a glance any straw that may have entered into 

 the paper. They are flat, possess thick outer walls and thin inner walls ; 

 the side walls have numerous, regular identations which in the case of the 

 long, narrow epidermal cells, give them the appearance of a two-sided 

 saw. The fibers of the four above-mentioned straws are about as wide as 

 linen fibers but they are shorter. They are not lignified and have rela- 

 tively thinner walls than linen fibers. The ends almost always come to a 

 point and often are forked. The numerous dislocations are also striking, 

 these however, do not exist originally, but are the result of the processes 

 of paper manufacture. Moreover, straw-fibers are of very uneven thick- 

 ness, some being very thin, others very thick and short. Another import- 

 ant difference between straw and linen fiber consists in the state of their 

 preservation. Straw fibers are always readily recognized in paper by all 

 their properties ; the sharp and often forked ends being especially notice- 

 able, whereas linen fibers occur mostly in fragments, which, furthermore, 

 are usually torn and macerated. According to Wiesner the average di- 

 ameters of straw- fibers are as follows : Barley, 5-12; rye, 9-17; oats, 10-21, 

 and wheat 10-21 mikra. Corn-fibers may be distinguished by their great 

 diameter (10-82 mikra) and by their form, i. e., they commonly have blunt, 

 forked, knotty ends, which sometimes even appear branched. Their 

 length is considerable, varying from 0.4 to 5.6 mm. The fibers are, as a 

 rule, relatively thin-walled ; the lumen appearing as a narrow line. Ac- 

 cording to Wiesner they contain an iron-green tannin, and, in contrast to 

 the fibers obtained from oats, barley, rice, wheat and rye, are lignified. 

 Corn-husk paper may, therefore, be distinguished from the ordinary straw 

 paper and from genuine rice paper by the fibers (Fig. 3). The various 

 kinds of straw papers, to the contrary, can only be distinguished with 

 certainty from each other by the epidermal cells, their form and dimen- 

 sions. The latter are, according to Wiesner, as follows : 



