INTRODUCTION. 5 



of reproduction possessed by that generative 

 organ. , On the contrary, when no seeds (which 

 are the oviparous produce) are perfected, the 

 effort at reproduction by offsets is increased. 

 This observation should be always kept in mind 

 by the florist, in order that he may have re- 

 course to it when necessary for the purpose of 

 increasing either seeds or offsets, as he may wish. 

 Solid bulbs have been described by botanical 

 physiologists, and the tulip is given as an in- 

 stance (Principia Botanicd). But this is a mis- 

 take ; the bulb being evidently composed of ab- 

 breviated leaves, enclosed within a thin integu- 

 ment or covering, similar to the hyacinth, only 

 fewer in number. These leaves are mostly 

 elongated, and accompany the rising stem to 

 which they peculiarly belong ; in which effort 

 they become exhausted, and die along with the 

 stem, or when the seeds are ripe. During the 

 growth of the parts just mentioned, as well as of 

 the roots which supported them, the next year's 

 bulb is formed to carry on the succession. It 

 has been advanced by some writers, that the 



