252 POLL WING NA TURE. 



have acquired a wholly different view of things. You would 

 have said that the corolla is tubular, greenish, 

 with a rosy limb, deeply divided into five 

 lobes. And in so doing, you would have 

 run no risk of deceiving yourself. The in- 

 dications given by Nature herself are the 

 most precious ; they are the lessons of a 

 teacher who cannot err : never pass them 

 by with indifference or neglect. In your 

 study of the different parts of a vegetable, 



Fro. 57. The Com- 

 mon Centaury. follow, as far as possible, the actual move- 

 ment of the sap. 



The calyx of our gentian has, like its corolla, the form of a 

 five-divided tube ; which, indeed, is one of the usual characters 

 of the Gentian family. 



But it is important here to take notice of this fact, because 

 it is not, as at first sight you would suppose, the corolla, but 

 the calyx, which encircles the base of the ovary. The tube of 

 the corolla stops towards the middle of the latter organ, and 

 nearly on a level with the linear divisions of the calyx. You 

 must be careful not to confound with these calycine divisions 

 the green foliola which lie around the base of the flower, and 

 which are neither more nor less than abortive leaves. 



Now call to mind that the flower is an union of concentric 

 whorls, or of rings set one within another. The staminal whorl 

 and the carpellary whorl, surrounded by a double perianth 

 (corolla and calyx), are here composed the first, of five sta- 

 j and the second of a bi-lobed ovary, surmounted by a 



