2IO THE JOURNAL OF PHARMACOLOGY. 



examined more closely microscopically showed no trace of a medulla, a 

 coarsely striated fibrous sheath, not very thick epidermal scales, whose 

 slightly thickened fore edge sometimes ran transversely or sometimes on 

 the slant, and always showed an imbricate arrangement. The scales were 

 more broad than high, often half or entirely cylindrical. A Leicester wool 

 known as long drawing was about 30 to 50 /-t thick) a medium thread at 

 base 42, middle 47, tip 42 ,a thick) and almost without a medulla. Even 

 normally thick parts of the hair showed single narrow and long medullary 

 isle cells, this serving to identify them as grannen hairs and differentiate 

 them from the Merinos. 



lyOngitudinally they showed great irregularities in thickness. The 

 fibrous sheath was distinct and coarsely striate. The scales were thin and 

 often lacking at the tip ; their edge was either slightly or not at all 

 thickened, were mostly imbricated, at some places they were indistinctly 

 plated. For that reason the indentations of the fiber were indistinct or 

 lacking. 



Microscopically the coarser ones approach more closely the characters 

 of the ordinary domestic wools. The thickness increases rapidly from 

 the sharp lamb point : 3 mm. below the tip they were 30/^. thick ; 5 cm. 

 away from it the medullary isles start with a strand thickness of 38 p-. 

 At the middle of the 12 cm. hair the average thickness is about 70 /^., at 

 places however 90 //, and here is found a 40 to 60 ,« thick medullary 

 cylinder consisting of two or three rows, which as it approaches to a 50 a 

 broad base, becomes single-rowed and finally consists of but elongated 

 medullary isles. In fact, the older wools (without lamb tips) must 

 show a more uniform course of thickness and medulla. The epiderm is 

 generally scaly, seldom arranged in plates. Where the medulla is very 

 broad the microscopical picture will resemble that of a goat hair on account 

 of the seeming absence of the fibrous sheath, and the several. rowed and 

 transverse medullary cells. Moreover, in the case of these coarser Leices- 

 ter sorts (which are known as Long-coarse) the medulla is, notwithstand- 

 ing the great thickness, often lacking at places, generally only one rowed 

 and slightly developed. 



Ordinary Domestic Wools. — Their microscopical properties become more 

 apparent when we characterize some extreme sorts. For instance, take 

 an ordinary Hungarian domestic wool of inferior quality. It can im- 

 mediately be observed that the straight staple is composed of two kinds 

 of hairs. In the first place 10 to 15 cm. long grannen hairs forming the 

 free staple end. These are 50 ;>■ thick and possess a continuous medullary 

 cylinder. These grannen hairs are quite stiff, almost bristly, straight and 

 sleek (Fig. 4). Secondly, wool hairs are present ; these being but 5 to 

 7 cm. long and only 30 n thick, and therefore only assist to form the inner 

 half of the staple. They possess no pith and are coarsely sinuous (quarta 

 or even coarser). 



