CANNABIS SATIVA 2.41 



Pericyclic Fibers. — Bredemann (4) and Heuser (15) have 

 pointed out that staminate plants produce fibers of better quality 

 than the carpellate ones; and, despite the fact that the number of 

 carpellate plants slightly exceeds the staminate in a given crop, the 

 percentage of fiber content is greater for the staminate plants than 

 for the carpellate ones. 



Early in ontogeny, the pericyclic region becomes multilayered, 

 and the cells which comprise it are noticeably larger than those of 

 the adjacent cortical parenchyma. The pericyclic cells enlarge, 

 elongate, become conspicuously vacuolate, and the cytoplasm 

 finally forms a thin layer against the primary wall. As the process 

 of secondary wall formation continues, the lumen of each fiber 

 becomes increasingly smaller, the cytoplasm is concentrated into a 

 smaller space; and, in some instances, the cell of the nearly mature 

 fiber is wholly filled with a granular cytoplasm. When the fiber is 

 completely mature, the cytoplasm disintegrates so that only 

 traces of desiccated material remain in the elongated oval lumen 

 which occupies about one-third of the transection of the cell. 



The wall of the fiber consists chiefly of pure cellulose, but the 

 proportion does not run as high as in the flax fiber. The amount 

 of cellulose in one of the best types of Italian hemp was found to 

 be 77.77 per cent. The cell walls frequently exhibit stratification, 

 resembling those of flax in this respect, but the fibers are less trans- 

 parent, and the lumen is less easy to distinguish because of surface 

 striations. 



In transection, a single fiber is three- to seven-angled; but owing 

 to secondary growth of the stem, it may be much compressed so 

 that the angles become somewhat rounded or flattened. The 

 average diameter is ix ju; but there is great variation between 

 individual fibers, extremes of 16 to 50 )u being reported by Matthews 

 (ii), and Cross and Bevan (10). The diameter for a given fiber 

 is variable, since the fiber is tapered at both ends, and there is also 

 a wide range in the length, which may vary from i to 10 cm. The 

 average is between 3.5 and 4 cm., according to Heuser (15), while 

 Matthews (xi) gives a somewhat lower figure, 2. cm. The tips of 

 the fiber cells usually are blunt or rounded, but some are forked, 

 this being regarded as a differentiating characteristic between the 

 northern and southern varieties of hemp, branching being more 

 frequent in the latter. Schilling (17) has pointed out that the 

 bifurcation of hemp fibers can be experimentally induced during 



