70 STUDIES IN INDIAN TOBACCOS. 



to the variation in the leaves on the same plant. The first 

 formed leaves (2 or 3 in number) which remain on the ground, 

 whatever the habit, generally do not possess the characteristic 

 shape of the other leaves and must be left out of account. In 

 some types all the remaining leaves, including the inflorescence 

 leaves, are of the same form and only differ in size (types XVI, 

 XLVIII and LI). In others the inflorescence leaves, generally 

 linear, are quite different to the lower leaves, and there is in the 

 latter a gradual change in shape and in the acuteness on the apex 

 according to the position of the leaf of the stem — the upper ones 

 beino- o-enerally narrower with more acuminate apices than the 

 lower ones (types XII and XIII). The variation is, however, 

 gradual and one of degree only, e.g., elliptical leaves tend to 

 become lanceolate. In the descriptions such gradual changes 

 have been indicated where possible and the photographs and 

 measurements have been taken from the 4th, 5th and 6th leaves. 

 The leaves may be sessile or petiolate ; in the latter case the 

 petiole is invariably alate. The narrow strip of lamina forming 

 the wings is generally very undulate and the width ma}^ vary 

 with the position of the leaf on the plant. Thus, in type V the 

 vvino-s are so broad in the upper leaves as to make them appear 

 almost sessile. In the majority of the types the leaves are 

 amplexicaul and decurrent. The breadth of the decurrent strip 

 of lamina and its length varies considerably in the various types, 

 and the latter may be as much as 5 cms. (type LI). Many of the 

 leaves are auriculate, the size of the auricles being characteristic 

 of the type. In the general shape of the leaves the types fall into 

 three classes : (1) those with lanceolate leaves having acuminate 

 apices (types XI, XII and XIX), (2) those in which the leaves 

 are broad in the centre and taper towards both the, apex and the 

 base ( types XXXI and XXXII ), (3) those in which the leaves 

 are elliptical with acute or somewhat obtuse apices, the lamina 

 being somewhat reduced at the base (type XLI, XLVIII and 

 LI). Within each class considerable differences are found, especi- 

 ally in the amount by which the lamina at the base of the leaf is 

 reduced ( cf types XXXVIII and LI). 



