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THE JOURNAL OF PHARMACOLOGY. 



and coarsely striate. The ends of the hairs for the length of several cen- 

 timeters are entirely smooth and without scales and consist therefore only 

 of a cylindrical bundle of fibers. The entire fiber (hair) is smooth, vitre- 

 ously glossy, irregularly thick and frequently more or less flattened. 



Other coarse domestic wools also, as for instance an examined sample of 

 German wools, although very thick, show but little or no medulla, even 

 where they were abnormally thickened. Fig. 7 illustrates this. 



Zigaya Wool. — Most wool from South Russia and Bessarabia, coming 

 over Odessa or Roumania, is called Zigaya wool and structurally is en- 

 tirely different from Zigarra wool, although they resemble each other ex- 

 ternally. 



Fig 8. 1,0ns Austrian wool. <j. wool hairat apex ; 

 h. thick grannen hair; concave scales. 5; central 

 cjlinder, m ; and slriations,/. X 35o- 



The fine wool hairs can easily be distinguished from the coarse grannen 

 hairs. The latter are verj' long, gloss}' and only dull at the tip. At the 

 tip, which is 85 ,a wide, is found the large medullary channel (45 p. wide) 

 which is composed of rounded cells, that contain much granular matter. 

 Only a few centimeters below the cut off tip can we first see the plated 

 epithelium which consists of almost isodiametric, mostly five-angled, ele- 

 ments with thickened edges. The large medullary cylinder is about half 

 as wide as the hair. The epidermal cells are distinctly concave. At the 



