256 Journal of the Asiatic Society of Bengal. [N.S., XIII, 



Bournei, Fyson occurs everywhere on stony hill sides. In 

 Osbeckia Wightiana there is no -well -marked adaptation which 

 would explain its presence in these situations. In every visible 

 character, except the peculiar scales of the calyx tube and a slight 

 silkiness of the under sides of the leaves, this dry open sun- 

 loving species is almost indistinguishable from Osbeckia reticu- 

 lata, Bedd. which occurs in woods and moist ground. The slight 

 silkiness of the under sides of the leaves seems too slight a 

 protection against transpiration to account for the difference 

 in habitat and is matched by the coarse hairiness of the leaves 

 of the other species. This adaptation of hairiness is well shown 

 in several species of Anaphalis, A. travancorica, A. Beddomei, 

 A. neelgerryana, A. brevifolia, and A. Bournei: as contrasted 

 with A. Wightiana and A. aristata which grow in moist places, 

 and have green glandular leaves, though they also are white 

 underneath. A. travancorica and A. Beddomei occur as 

 densely branched rounded shrubs along the tops of the preci- 

 pices which bound the downs near Kodaikanal, where they 

 are enveloped , every afteruoon during the summer months with 

 the dense mist that rises from the plains, and, at other times, 

 are exposed to strong dry winds. In company with other 

 species of Anaphalis the leaves hang for a considerable time 

 after they have died, so that the lower stems are thickly 

 clothed with these dead leaves. The suggestion is hazarded 

 that a certain amount of absorption of water may take place 

 from the air entangled in the interior of the bush. Ana- 

 phalis neelgerryana which grows specially on bare crags 

 on the Nilgiri plateau, but not on the Pulneys, shows the 

 further adaptation of the leaves being closely packed together. 

 In Anisochilus dysophylloides, which, as ho- been mentioned, 

 grows in the driest situations, the leaves are crowded and 

 fleshy and arranged, curiously for a Labiate, in six not in four 

 rows. Smooth fleshy leaves are well shown in Kalanchoe grandi- 

 flora, Wight and Arnott, which occurs abundantly on the Snow- 

 don to Dodabetta ridge on the eastern side of Ootarainund, and 

 very prominently also in two epiphytes, Peperomia reflexa A. 

 Dietr., and the orchid Saccolabium filiforme Lindley. This 

 latter shows the interesting peculiarity of having flowers ot 

 different colours on the two plateaus. On the Nilgiris they are 

 pink, on the Pulneys orange streaked with red. No other 

 difference can be made out. Since the plant is an epiphyte, the 

 difference cannot be due to any difference in the mineral salts 

 of the soil. It seems to be a clear instance of a mutational 

 change, all the more remarkable because in cultivated flowers 

 pinks and yellows are not, as a rule, interchangeable ; the former 

 colour being usually dissolved in the cell sap, the latter, with 

 red, contained in special plastids. « 



While on the subject of adaptations to xerophytic condi- 

 tions, what seems to be a curious anomalv deseives notice 



