102 



BRITISH FLOWERING PLANTS 



are very small. A larger species ( Vinca major), 

 also with blue or white flowers, but with the 

 borders of the divisions of the calyx and of the 

 leaves fringed with hairs, is also occasionally met 

 with. 



Allied to the Periwinkle is the beautiful but 

 poisonous shrub so common round the Mediter- 

 ranean, the Oleander {Nerium Oleander). It has 

 green lanceolate leaves, and red, or occasionally 

 white or yellow, flowers. The caterpillar of one 

 of the most beautiful of the European Hawk- 

 moths, the Oleander Hawk -moth {Dafihnis nerii) 

 feeds on this shrub as well as on Periwinkle. It 

 is green or yellowish, with a white line on each 

 side, a blunt yellow horn on the back, and the 

 front of the body yellow, with two blue spots 

 surrounded with black on the back of the third 

 segment behind the head. The moth is 4 inches 

 in expanse, and is also green, varied with pink 

 and violet- It is common throughout Africa and 

 the warmer parts of Europe and Asia, but is only 

 found in England as an occasional visitor of great 

 rarity. 



Order LI. Gentianacecz 



This Order resembles the last in its large tubular 

 flowers, generally blue, pink, or yellow ; but the 

 corolla has from 5 to 8 lobes, and the two ovaries 

 are not united. 



Centaury — Erythr<za Centaurium 



(Plate LIX) 



This pretty little plant is common in fields and 

 meadows, preferring open sunny places, and flowers 

 from June to September. It is an annual, and 

 throws up from the root one or more smooth erect 

 branching stems. The leaves are ovate or lanceo- 

 late, smooth, sessile, and opposite ; and larger 

 leaves form a thick rosette round the root. The 

 flowers are pink, the tube of the corolla is longer 

 than the calyx, and the open part is divided into 

 5 oval petals. The stigma of the ovary is rounded 

 and cleft. The whole plant is very bitter, and, 

 like many species of Gentian, has been employed 

 in medicine as a valuable tonic. 



