INSECTIVOROUS PLANTS. 



403 



good roots for the size of plant are developed. Darwin mentions 

 that the roots of Dionrea are very small : those of a moderately 

 fine plant which he examined consisted of two branches, about 

 one inch in length, springing from a bulbous enlargement. I have 

 frequently found Dionaea roots six inches in length ; but they are 

 deciduous, and I can only conjecture that the roots mentioned by 

 Darwin were not fully grown at the time they were measured. 

 What is here stated of the natural habits of Dionaea applies 

 more or less to all insectivorous plants. 



Such is a brief survey of a few of these most interesting 

 plants, whose habits, in some respects, as already said, are 

 curiously allied to those of members of the animal kingdom. 

 In conclusion, I should like to add a few words on their 

 cultivation. They all require pretty much the same descrip- 

 tion of soil and general treatment. Nepenthes alone demand 

 much heat, an average temperature of 70° suiting the 

 majority of them very well. The soil should consist of good 

 fibrous peat, with the earthy matter shaken well out. To this 

 should be added from a third to a half of chopped Sphagnum 

 moss, with a sprinkling of charcoal, potsherds, and silver sand, 

 all thoroughly well mixed. This will form a free, open compost. 

 Owing to the large amount of water required, good drainage 

 must also be given. In repotting Nepenthes, care should be 

 taken not to injure the delicate roots. It is better not to shake 

 the old soil out, unless it has become soured and unwholesome. 

 In that case the soil should be washed away, thus preserving 

 the roots. Very small pots or baskets should be used in com- 

 parison with the size of the plants. The best time for repotting 

 is about the middle of February. The plants should be placed 

 near the glass, and not shaded too heavily unless in very bright 

 sunshine. To have abundance of pitchers produced, the plants 

 should be frequently cut back, as when growing too freely they 

 fail to produce pitchers — and this is just what might be expected, 

 bearing in mind what has been said regarding their habits. So 

 long as the plant is deriving plenty of nourishment from its 

 roots it has the less need to develop pitchers, and hence also 

 the necessity for confining the roots in small pots. In the seed- 

 ling Nepenthes, the first leaves produced after the cotyledons 

 are small winged pitchers, and a succession of these is developed 

 before a lamina becomes apparent on the young leaves. With 



