Miscellaneous Facts and Obser'uations. 173 



I have attended to the change, it has appeared first 

 on the iomer side of the petal. 



Felix Robertson, M. D. 

 Letter to the Editor, dated Nashmlle 

 (TenesseeJ, September 5th, 1805. 



17. Dr. Darwin is of opinion, that the corolla 

 forms a pulmonary system " totally independent of 

 the green foliage," and that this respiratory system 

 belongs to the sexual or amatorial parts of the fructi- 

 fication only ! He asserts, that each petal is furnish- 

 ed with an artery, " which conveys the vegetable 

 blood to its extremities, exposing it to the light and air 

 under a delicate moist membrane, covering the internal 

 surface of the petal, where it often changes its colour, 

 as is beautifully seen in some parti-coloured Poppies, 

 though it is probable (he observes) that some of the 

 iridescent colours of flowers may be owing to the 

 different degrees of tenuity of the exterior membrane 

 of the petal, refracting the light like soap-bubbles. 



(C 



The vegetable blood (continues our learned au- 

 thor) is then collected at the corol-arteries, and re- 

 turned by correspondent veins, exactly as in the green 

 foliage, for the sustenance of the anthers, and stig- 

 mas, and for the important secretions of honey, wax, 

 essential oil, and the prolific dust of the anthers, and 

 thus constitutes a pulmonary organ." 



