Vegetable Physiology, 13 



nated. The bumblebee, above all other insects, I would have 

 befriended, for its robust and hardy form enables it to get 

 abroad and be employed in this useful work, when weaker 

 insects are confined by inclement weather. 



The stamens are changed into petals in double flowers, 

 which are consequently unfertile : they are often likewise 

 obliterated, either by excessive nourishment, or when the 

 plant increases much by root, as in the Fiery Lily (iilium 

 bulbiferum). If this excessive production of root is very 

 remarkable, it sometimes prevents the production of the 

 flowers of the plant entirely, as is the case with some early 

 varieties of the potato ; for Mr. Knight demonstrated that if 

 the tubers of such were removed as they were produced, the 

 plants blossomed as freely as later-tubering varieties; and, 

 mcc versa, the removal of the blossoms of tuberous-rooted 

 plants promotes the size and number of the tubers. It is not 

 to be supposed, however, that fibrous-rooted plants are not 

 similarly affected. I have observed a gooseberry bush, that, 

 from being under the shade of trees, &c., had never borne 

 fruit during a series of years, to throw out annually a very 

 excessive number of suckers. Again, fibrous-rooted land 

 plants, which by accident are growing in water, increase the 

 number of their radiculag enormously, whilst their fructification 

 is diminished and abortive in proportion. 



Of the pistils, the two essential parts are the stigma, or 

 orifice for the admission of the pollen, generally on the sum- 

 mit; and the germen, which is the rudiment of the future seed- 

 vessel. Pistils, like stamens, are obliterated in double flowers, 

 otherwise they are not so liable to become petals. 



The production of the seed is " the being's end and aim " 

 of every plant : all its other parts, by ministering in some way 

 or other to its maturity, indicate its importance. Not per- 

 ceiving that a description of the various parts of a seed would 

 lead to any practical hints to the gardener, I shall proceed to 

 the consideration of the phenomena of germination. 



When a seed is placed in a situation favourable for vege^ 

 tation, it soon swells, its skin, or testa, bursts, and a shoot, 

 denominated the radicle, is protruded ; and, in a short time, 

 this is followed by a second, which is named the plumida. The 

 radicle by degrees sinks into the earth, and becomes a perfect 

 root; whilst the plumula rises above the surface, to expand, 

 and complete the form of the perfect plant. The essentials 

 for germination are several. The first of these appears to be 

 the perfect maturity of the seed; for, although Sennebier 

 found that peas will sometimes vegetate, though sown in a 

 green and soft state, yet it is certain that the plants raised 



