326 STUDIES IN LIFE AND SENSE. 



case of these carnivorous plants. There can exist no doubt in the 

 mind of the scientist that the habit in question has been developed ; 

 that, in short, it is acquired, and not original in its nature. Varied 

 circumstances favour such an opinion, which is in perfect harmony, 

 it 'need hardly be added, with the general doctrine of evolution, 

 maintaining the production of new forms of life through the modi- 

 fication of the old. The carnivorous plants are thus discovered to 

 unite singularities of structure to peculiarities in the way of diet. 

 The modifications of habit which have made them animal-feeders 

 have been accomplished pari passu, and through the development of 

 structural changes in the leaf and in other features of their material 

 organisation. The deviation from the usual and ordinary course of 

 plant-life, here as elsewhere, betokens the beginnings of new and 

 altered phases of existence. The variation from the old species, in 

 a word, is but the prelude to the establishment of new species and of 

 new ways of life. 



One of the most powerfully convincing facts connected with the 

 altered " habits " of the carnivorous plants and their allies, and 

 demonstrative of the gradual modification through which their 

 existent condition has been attained, consists in the observation that 

 between their animal-like habits and the ordinary life of common and 

 normal-living plants there are to be found many connecting links and 

 stages. The assumption of a parasitic life by the mistletoe and other 

 plants serves to show how an ordinary plant may acquire an abnormal 

 or unusual habit without sacrifice of the essential characters of its plant- 

 nature. It will be remembered that the mystic parasite of the oak 

 and apple has green leaves of its own, and that it elaborates certain 

 food-materials by aid of these organs. Although the mistletoe is by 

 no means the first term in the series of links whereby the unusual 

 is connected with the normal in plant-life, yet it serves physiologically 

 as an interesting half-way house between its common neighbours and 

 its carnivorous fellows. Mistletoe has developed the parasitic habit 

 of dependence upon another living being, and that a plant, for the 

 largest part of its dietary ; but its relations do not extend outside 

 the bounds of its own kingdom after all. Before, however, the 

 mistletoe stage can be reached, certain preliminary conditions must 

 have been represented and effaced in the development of the altered 

 phases of life we now behold. Probably the first step in the develop- 

 ment of a parasitic life in the higher plant began with mere attach- 

 ment to a neighbour-plant. A weakly stem to-day climbs upon, or 

 twines around, a support. The ivy, hop, French bean, honeysuckle 

 and the like, illustrate not merely the stage of attachment by way 

 of mere support each plant having its own root in the ground but 

 we may also discover that in their ways and methods of climbing or 

 twining, as the case may be, there are represented fixed and defined 



