132 



PLANTS WITH TRAPS AND PITFALLS TO ENSNARE ANIMALS. 



glandular cells situated on the lining of the pitcher; and the whole process, wherein 

 they are concerned, corresponds to that which obtains in the pitchers of Ne]Dent]ies, 

 and which will be more thoroughly discussed in the case of these latter plants. 



The species of the genus Nepenthes, of which we know at the present time 

 thirty-six, are all confined to the tropics. Their area of distribution extends from 

 New Caledonia and New Guinea over tropical Australia to the Seychelles Islands 

 and Madagascar, and over the Sunda Islands, the Philippines, Ceylon, Bengal, and 

 Cochin-China. They only flourish on marshy ground on the margin of small 

 collections of water in damp primeval forests. There the seeds germinate in 



from 



the boggy 



::A^^ 



Fig. 23. — Young Nepenthes plants. 



shallow water. The young plants (see fig. 23), which spring 



ground, have their leaves ar- 

 ranged in rosettes just like 

 those of Sarracenias (see fig. 

 20). They are, too, so nearly 

 identical in form with the 

 latter that anyone seeing a 

 young Nepenthes plant for 

 the first time, and not knowing 

 the history of its development, 

 would take it for a Sarracenia. 

 The leaves, succeeding the 

 cotyledons and forming a circle 

 above them, rest their lower portions upon the mud, but their upper parts are 

 curved upwards, and each carries at its extremity a scale resembling a cock's comb, 

 which is, strict speaking, the lamina. This scale roofs over a slit-like aperture, the 

 entrance to a cavity within the swollen petiole. In addition a green lobe with a few 

 coarse projecting points is to be seen on either side of the orifice. 



Altogether different from the rosettes of young Nepenthes plants are the foliar 

 structures clothing the stems which subsequently arise from the rosettes (see fig. 24). 

 In these leaves the lower part of the petiole is winged and flat, has a linear or 

 lanceolate outline, and resembles the leaf -blade of Dracaena; its functions, too, are 

 those of a green lamina. This expanded section of the leaf-stalk passes next into 

 a part which is terete and coiled like a snake, and acts as a tendril. Every stem or 

 branch belonging to a plant, whether living or dead, with which this part of the 

 petiole comes into contact, is seized and encircled by it; and the third portion of 

 the petiole, i.e. the pitcher, being situated at the extremity of this clasping portion, 

 IS thus slung upon the branch of some other plant growing at the edge of a pool 

 of water, Meanwhile the Nep>enthes plant rises higher and higher above the wet 

 soil where its seeds germinated and the young rosette rested, becomes entangled 

 with the ramifications of the underwood and with prostrate branches of trees of 

 the primeval forest; in a word, with everything available as a support, and so not 

 infrequently climbs, as a true liane, to the tops of trees of moderate height. 



The pitcher must be looked upon as an excavated portion of the petiole, and 



