542 CONSERVATIVE ORGANS. [LECT. X. 



throw out roots, and produce plants in every 



respect resembling the plant to which they belong, 

 they are termed proliferous (prolifera). The 

 plant which displays the most beautiful example of 

 the proliferous leaf is the Cotyledon calydnum; 

 see fig. 1. Plate 10, in which the letters a. a. a. 

 a. a. a. mark the young plants springing from the 

 serratures of the leaf, some of them sufficiently 

 advanced to admit of their being separated from 

 the leaf, and sustained by their own vegetative 

 powers. The attachment of the young plants is 

 extremely slight., and evidently effected by a cord 

 of umbilical vessels, originating in the proper 

 vessels of the leaf. Leaves of this description 

 have the closest affinity with those bulb scales 

 which, as I demonstrated to you in treating of 

 bulbs, produce new bulbs when they are separated 



