376 Mr Philip Sewell's Observations upon the 



The above is perhaps the most evident instance, those 

 species with dull and glabrous leaves being from several 

 sections ; as also those with a low growing habit in their 

 earliest stages. 



Note wpon the Movements of Young Leaves of Salvia Species 

 'probably attributable to the Effects of Dry Air and 

 consequent Evap)oration. 



Jan. 21, 1890, 11 p.m. — A pot of seedlings of Salvia 

 canarien^is which had remained for some hours in a dry 

 warm position in a dwelling-room showed five seedlings out 

 of nine, with the second pair of leaves (cotyledons excluded) 

 in more or less close contact ; each was about 16 

 mcL. iong, and had been separate from the other before 

 the plants were brought into the room. The young leaves 

 were closely pressed, one against the other, towards the base, 

 but the tips of the leaves were generally somewhat retiexed. 

 All the seedlings would, in all probability, have so responded 

 to the stimulus, of whatever nature it might be (dry air 

 probably), but the crowding together in the pot caused 

 petioles or laminae of one or another seedling to interfere 

 with the movements of its neighbours. 



In one case the third pair (larger) were developed, and 

 they were closely appressed for the greater part of the 

 extent of the lamina, the species being only 5 mm. apart. 

 The petiole did not appear to move much, if at all, nor did 

 both leaves move towards each other equally ; the lamina 

 of one would incline towards the lamina of the other, making 

 an angle with its petiole, whilst the lamina and petiole of its 

 opposite leaf might be curved much in the same direction 

 throughout. 



Jan. 22, 10 a.m. — The seedlings having been kept in the 

 same position since they were last observed showed a 

 separation of the leaves of those pairs, which, before, were 

 observed to have been in partial or complete contact. In 

 only one case was there any contact of the lamina of one 

 leaf with that of its opposite leaf. 



The following were the measurements of the distances 

 between the tips of the various leaves : — 



