242 THE WONDERS OF VEGETATION. 



ent (Mesembryanthemum crystallinum\ all the super- 

 ficial cells of the leaves are so excessively developed 

 that they look like so many small bags filled with 

 limpid waters ; hence the appearance of the plant, 

 which seems to be covered with drops of frozen wa- 

 ters and refreshes the eye in the midst of a dry and 

 dusty landscape. 



In other plants the leaves seems to have a special 

 attraction for insects, which, leaving blossom and fruit 

 alike unharmed, are irresistibly attracted by a myste- 

 rious charm in the leaves. Legions descend upon the 

 unfortunate trees, among which the evergreen coni- 

 ferse alone harbor 400 species, all more or less hurt- 

 ful. One of these, the pyralis, destroys the leaves of 

 the vine and with them the life of the whole plant, 

 thus carrying despair to all the vine-growing regions 

 of Europe and our own country. For even in our own 

 vineyards the obnoxious insect has made its appear- 

 ance, and, so far, science and experience have been 

 alike unable to contend with the feeble and apparent- 

 ly insignificant moth. 



THE OTJVIRANDRA FENESTKALIS. 



In the conformation of its leaves this plant, a na- 

 tive of Madagascar, is not less remarkable than the pre- 

 ceding. Its leaves assume oddly enough the form 

 of windows, and hence the odd name the plant is 

 made to bear. The vascular network is left without 

 the diploe, which covers the leaves of all other plants 

 of this family. It is a vigorous plant, growing at a 



