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tus connected with their organization, for they are true alembics. The stem of a 

 particular kind of Bamboo, and also of a Cissus, or wild Vine, have been found 

 charged with limpid and wholesome water, grateful to the weary and thirsty tra- 

 veller. In these last, it is obvious the liquid is an elaboration of the plant. This, 

 too, is the case with the Agapanthus umbellatus, or African Lily, which often 

 distils water from its gracefully pendant leaves ; and in one instance this distilla- 

 tion was so copious during the night, as nearly to destroy a work-box, accidentally 

 left beneath its foliage : hence the intention is obviously to enable the plant to 

 water its own roots. It belongs to the parched and sandy desert of Africa. The 

 Calla cethiopica is another instance of the same kind : it is a native of the Cape. 

 We almost esteem it as a half-aquatic ; and yet it is found a denizen of the desert 

 — its natal soil an arid sand. I am informed, however, that an individual who 

 communicated the fact, and brought a magnificent specimen to this country, which 

 I have seen, has found this plant where the ground around it was as wet as if it 

 had been saturated with a heavy dew or a gentle shower of rain. The Calla 

 wthiopica, like its congener, the Agapanthus umbellatus, distils water from the 

 tips of its leaves, and in both cases the process takes place during the night. 



Not the least singular among the phenomena of the vegetation of the desert, 

 is the existence of succulent plants ; precisely where we should least of all expect 

 to find them ; such as the Cactuses, Mesembryanthemums, and the Stapelias ; 

 the last of these being emphatically called " the Vegetable Camel." The curious 

 berry met with by Mr. Campbell, in the desert, full of limpid water, and which 

 some little mice were observed to treasure up in their retreats, will also be remem- 

 bered, and suggest a train of singular and useful reflections. 



But the most curious of all is, certainly, the Tillandsia, or Water Withe, of 

 Jamaica, belonging to the curious tribe of Epiphytes — dwellers on trees, though 

 they do not live upon their kind, like parasites. The Tillandsias are associated 

 in their port and habit with the Bromelias and Silbergias. The Tillandsia has 

 what may be called a hollow stem ; it is, in fact, a tank or cistern, formed by the 

 leaves which overlap each other in an imbricated arrangement, and in ordinary 

 conditions of the atmosphere constitutes an envelope alike impervious to air and 

 moisture. This tank catches and retains the condensed dews — very copious in 

 tropical countries — or the early and latter rains, retaining the supply when that 

 which falls upon the ground is promptly absorbed by the thirsty and porous soil. 

 Here, then, is a living well where insects and birds may slake their thirst, and 

 quadrumana and others among the Scansores may apply to as containing a cool 

 and refreshing beverage. So far there is much to admire in the beneficent pro- 

 vision : but the tale of interest is not half unfolded. In Earl Fitzwilliam's exten- 

 sive conservatories, at Wentworth House, there were two plants of the Tillandsia, 

 and being in different compartments were subjected to varied temperature. In the 

 one, the temperature of the external atmosphere was 71° Fah., and in the other 



