WEEDS AND WILD PLANTS. 



345 



currants, and gooseberries come up from bird-dropped seeds. The ash 

 and horse-chestnut appear in a troublesome way from the same cause, 

 and the elderberry is a pest. I never have known, in my garden, an 

 apple, pear, or plum tree to spring up spontaneously, though seedling 

 peaches occasionally appear. 



Amongst destructive weeds, I have seen the Dodder {Ciiscicta 

 epithymum, fig. 791) attack my cranberry plants, 

 but only on one occasion. I was too pleased to 

 have a specimen in the place to do it any 

 damage ; but as I did not destroy the dodder, 

 the dodder killed my cranberry. It is a most 

 destructive plant to clover, killing patches of it 

 a yard in diameter. It has no roots, but lives 

 by sucking out by dialysis the juices of the 

 plants on which it lives. 



In glancing at our weeds, it will be seen how far the presence of 

 the river Wandle in the garden influences their growth, for the greater 

 part of those which I have figured naturally flourish on the banks 

 of a river or on ground adjacent to it. 



Fig. 791. — Lesser Dodder. 



THE ALG^. 



" Spawn, weeds, and filth, a leprous scum, 

 Made the running rivulet thick and dumb." — Shelley. 



We have many Alga in my garden, which are interesting, as they 

 represent the lowest types of vegetal life. On the 

 palings of the Park and on the trunks of the trees a 

 green dust is formed in winter, which is the Protococcus 

 viridis (fig. 792). It is composed of minute 

 cells, and a high magnifying power is required 

 to examine them satisfactorily, 

 shows the plant magnified 600 times ; for 

 when increased only 100 times (fig. 792) the green dust still only 

 appears to be composed of fine particles. 





Fig. 793 Fig. 792.— Proto- 

 coccus viridiS* 

 X xoo diam. 



Fig. 793.— Ditto, x 

 600 diam. 



