THE JOURNAL OF PHARMACOLOGY. 235 



hair is but 40 // thick it will have no medulla. At the very tapering tip 

 the epidermal scales are jagged, toothed, and higher at the fore edge, and 

 the fiber edge is finely serrate. 



The pigment of the colored goat hair is seen in all the tissues. The 

 medulla appears black, but this is caused by air and granules of pigment. 



The hairs from the goat's beard are stiff grannen hairs, over 30 cm. in 

 length. At the base they are 100/^. in thickness, without a medulla; the 

 epidermal cells are very narrow and finely toothed, closely imbricate, 

 very thin, edge not thickened ; for this reason the hair here will have no 

 serrations at edge. Four to five scales cover the circumference ; their un- 

 covered portion is about 10/^ high and 40 to 50/^ broad. The fibers form 

 a uniform and close, coarse striation. In the center of the cross section 

 the fibers will be less close, and thus it often happens a medulla is found. 

 Further up the hair first decreases (90 to 95 /j-), then increases (120/^-) in 

 thickness without changing its structure. 



About 10 to 15 cm. above the base are first seen spindle-shaped medul- 

 lary cells that often look like broad fibers only. They grow more num- 

 erous and gradually are transformed into somewhat long and round cells, 

 that finally form a continuous medullary cylinder. Here the medullary 

 cells are somewhat broader transveresly, are arranged in several to four 

 rows and finally form a massive cylinder which is only surrounded by a 

 very thin fibrous layer and a scarcely visible epiderm. 



The medullary strand generally reaches to the broken-off tip of the hair. 

 The greatest width of this is about 150/^-, 10, 'j. of which go to the fibrous 

 layer on either side. The entire fiber is very uniformly round. 



3. Angora Goafs Hair {Mohair). 



A prime sort, Fig. 10, a, consisted of hairs about 18 cm. in length, very 

 evenly round and about 42 jj- in thickness at the cut base. The scales 

 were very thin, entirely flat, half to entirely cylindrical, broader than 

 high, often tapering, crenately or coarsely dentate, and here and there 

 finely toothed, without a medulla, without a conspicuous fiber striation, 

 entirely without granules ; characteristic and conspicuous are the broad 

 and evenly distributed fiber fissures. Irregularities in thickness of fiber 

 are entirely lacking. Greatest breadth is 50 p., serrations at edge entirely 

 lacking or are very fine and drawn out. Minimum thickness is 38 /^.. To- 

 wards the tip the scales become very fine, jaggedly toothed, finally en- 

 tirely lacking. Coarse hairs with medulla are not present. Natural ends 

 at tips. 



A coarser sort, 48 to 67 /^ thick, is not uniform, at places not columnar 

 (Fig. 10, b). 



Cap- angora wool (like ordinary wool of Capra hircus ango) is 12 to 



