40 JOURNAL, BOMBAY NATURAL HISTORY SOCIETY, Vol. XX. 



characters. Occasionally, in the genus Caryota, these segments are 

 aoain divided (bipinnatisect), their ultimate divisions resembling in 

 shape the fin or tail of a fish. 



The petiole (leaf-stalk) is usually large and stout and has a strong, 

 broad, sheathing base. The leaf-fall is, as generally in Monocotyle- 

 dons not a predetermined process, as observed in dicotyledonous 

 trees. After some time, when the leaf has reached the end of its 

 life-period, it gradually falls over, as the weight of the large blade is 

 too oreat for the dying petiole. The blade remains attached until 

 the stalk becomes so decayed that the leaf falls by its own weight or 

 wets broken off by wind or rain-storm. The sheath is often seen to 

 persist for sometime, its tough fibres forming a dense matting round 

 the bases of the younger leaves. In some genera (Calamus, Desmoncus) 

 the stem is surrounded above the petiole by a sheath-like stipule, 

 called ochrea. In a few species the ochrea forms a hollow smooth- 

 walled chamber, in which ants make a home {Korthalsia echinometra, 

 scaphigera, scortechinii, waUichicefolia). 



Within the leaf-sheath we often find stem-thorns, which are at 

 first flattened upwards against the stem and spread only after leaf-fall. 

 The stems and leaves of the Rattans often bear numerous recurved 

 spines which aid them in scrambling over trees and bushes. Also the 

 leaf-rachis Cmidrib) may be produced into a naked, barbed, whip-like 

 flagellum. 



The leaves are generally green on both sides, but occasionally of a 

 silvery white on the underside (Coperm'cia cerifera). In rare cases 

 blue the middle of some leaves shows concentric bands of yellow 

 and in the manner of a peacock's tail, as in the prickly Mauritia. 



Another important character is the direction of the leaves. The 

 segments may be arranged in a comb-like manner close to one 

 another, with a stiff parenchyma, allowing the rays of the sun to play 

 over their surface, and causing them to shine with a brilliant verdure 

 in the Cocoa-nut Palm, and with a fainter ashy-coloured hue in the 

 Date-tree, or they have a more flexible, grass-like texture, and are 

 curled near the extremity. The more acute the angle formed by the 

 leaves with the upper part of the stem, i.e., the nearer the leaves 

 approach the perpendicular, the bolder and nobler is the aspect of the 

 species to which they belong. A comparison between the Real Date 

 Palm and the Wild Date Palm will show this sufficiently. 



