DEOSEKA HOTUNDIFOLIA. 



CHAP. 1 



secondly, the power possessed by the leaves of render- 

 ing soluble or digesting nitrogenous substances, and 

 of afterwards absorbing them ; thirdly, the changes 

 which take place within the cells of the tentacles, when 

 the glands are excited in various ways. 



It is necessary, in the first place, to describe briefly 

 the plant. It bears from two or three to five or six 

 leaves, generally extended more or less horizontally, 

 but sometimes standing vertically upwards. The shape 

 and general appearance of a leaf is shown, as seen 

 from above, in fig. 1, and as seen laterally, in fig. 2. 

 The leaves are commonly a little broader than long. 



FIG. 2. 



(Urosera rotundifolia.') 

 Old leaf viewed laterally; enlarged about five times. 



but this was not the case in the one here figured. 

 The whole upper surface is covered with gland-bearing 

 filaments, or tentacles, as I shall call them, from their 

 manner of acting. The glands were counted on thirty- 

 one leaves, but many of these were of unusually large 

 size, and the average number was 192 ; the greatest, 

 number being 260, and the least 130. The glands are 

 each surrounded by large drops of extremely viscid 

 secretion, which, glittering in the sun, have given rise 

 to the plant's poetical name of the sun-dew. 



The tentacles on the central part of the leaf or disc are 

 8hort and .stand upright, and their pedicels are green. Towards 

 the margin they become longer and longer and more inclined 



