190 STUDIES IN INDIAN SUGARCANES 



small m the Saretha group, irregular, sparse and not infrequently deciduous 

 or absent in the Katha section, but occasionally more abundant in the 

 Mesangan varieties. In the Smanabile group they are strongly developed 

 and are usually long, an.d there are often a few scattered, very long setse, 

 standing out in the middle of the ligule. 



(11) Clasping stem at base. In the varieties in. the Saretha group the leaf 

 sheath at its base clasps the stem more widely, although the differences are n,ot 

 great. This is in accordance with observations made when comparing Katha 

 and Dhaulu of Gurdaspur. The extent of encirclement is expressed in terms 

 of the circumference of the stem., thus, 1"00 would mdicate that the leaf sheath 

 just encircles the stem once and I'.W would show that it goes one and a half 

 times round. The figures obtained for 8 Saretha and 10 Sunnabile varieties 

 measured in 1916 are 1*45 and 1*35 respectively — ^roughly the sheath passes 

 one and a half times round in Saretha and one and one third in Sunnabile. In 

 the larger series examined in 1917 the difference is reduced, although it is in 

 the same direction. The figures are 1'46 for Saretha and 1*39 for Sunnabile 

 groups. The Katha section clasps the stem most widely, 1*48 being its figure : 

 the Mesangan section gives the figure 1'43 and the Sunn f bile group 1*39. 



(12) Width at base. The Sunnabile varieties, in spite of less encirclement 

 of the stem by the base of the sheath, have wider sheath bases, and here too 

 the Mesangan section is intermediate between the Katha section and the 

 Sunnabile group. The average widths of the base of the leaf sheath are, for 

 1916, Saretha group 3-09", Sunnabile group 3-37" ; for 1917, Katha section 

 2" 79", Mesangan section 3' 16" and Sunnabile group 3*26." 



(13) Width at apex. Here too, the sheaths are wider in the Sunnabile 

 group, falling into fine with a greater thickeness of stem and greater width of 

 leaves. The 1916 measurements show averages of 1*23" for Saretha and 1'34" 

 for Sunnabile groups : in 1917 the figures being 1*22" and 1*30" respectively. 

 But a variation is to be noted in the Mesangan. section, which is not in this 

 case at all intermediate between the Katha section and the Sunnabile group. 

 The width at the apex of Mesangan section averages 1*40", that of Katha 

 section 1*11", while the Sunnabile group is intermediate with 1*30". 



(14) Length of mature leaf sheath. The length of leaf sheath appears to 

 differ less definitely in the Saretha and Sunnabile groups than that of joint and 

 lamina. In fact, while it is distinctly longer in Saretha in the 1916 measure- 

 ments of mature canes, little difference has been noted in those of 1917. This 

 may be due to the fact that the maxima are rather late and that, in the 

 immature canes of the latter crop, the full length of the leaf sheaths had not 



