ASSISTANCE OF INSECTS IN IMPREGNATION. 257 



fore is accomplished by an insect, the Tipula penni- 

 cornis, which enters the flower by the tubular part. 

 But that part being thickly lined with inflexed hairs, 

 though the fly enters easily, its return is totally im- 

 peded, till the corolla fades, when the hairs lie flat 

 against the sides, and allow the captive to escape. In 

 the mean while the insect, continually struggling for 

 liberty, and pacing his prison round and round, has 

 brushed the pollen about the stigma. I do not doubt 

 the accuracy of this account, though I have never 

 caught the imprisoned Tipula*. Indeed I have never 

 seen any fruit formed by this plant. Probably for want 

 of some insect adapted to the same purpose in its own 

 country, the American Aristolochia Sipko, though it 

 flowers plentifully, rarely forms fruit in our gardens. 

 That it sometimes does, I have been informed by the 

 late Lady Amelia Hume, since the first edition of this 

 work was published. 



The ways in which insects serve the same purpose 

 are innumerable. These active little beings are pecu- 

 liarly busy about flowers in bright sunny weather, when 

 every blossom is expanded, the pollen in perfection, 

 and all the powers of vegetation in their greatest vigour. 

 Then we see the rough sides and legs of the bee, laden 

 with the golden dust, which it shakes off, and collects 

 anew, in its visits to the honeyed stores inviting it on 



* Dr. Lamb of Newbury has lately sent me specimens of the flowers, 

 with the insict inclosed, from the Oxford garden, where they were 

 discovered by a young gardener. August 1813. 



S 



