LIFE OF DARWIN. 137 



ment by catching, killing, and digesting insects. They 

 may be called truly carnivorous plants. What an un- 

 expected reversal this was of the order of things hitherto 

 believed to prevail universally. Animals live on other 

 animals or on plants. Here were plants living on 

 animals, and keeping down their number. Moreover, 

 without a nervous system, the action of the parts of a 

 sun-dew leaf was proved to be as apparently purposive as 

 the combined action of the limbs of an animal. Without 

 a stomach, the sun-dew poured forth a digestive fluid as 

 effective in extracting and fitting the nutritious matter of 

 the insect for its own purposes as that of an animal. 

 Without sensory nerve-endings, there was a percipient 

 power in the sun-dew which recognised instinctively and 

 at once the non-nutritious nature of various objects, and 

 which responded to the most delicate chemical stimuli 

 and to the minutest weights. 



We cannot describe the little sun-dew better than in 

 Darwin's own words : " It bears from two or three to 

 five or six leaves, generally extended more or less hori- 

 zontally, but sometimes standing vertically upwards. The 

 leaves are commonly a little broader than long. The 

 whole upper surface is covered with gland-bearing fila- 

 ments, 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." 



