556 



THE PERIWINKLE FAMILY. 



and ornamental shrubberies that its na- 

 tural limits cannot well be traced. In 

 Britain, common in southern England, 

 and has been considered as truly wild as 

 far north as Durham and Yorkshire. 

 In Ireland it is only found va here planted. 

 Fl. summer. 



Fig. 664i. 



XLVIL PERIWINKLE FAMILY. APOCYNACE^. 



A large tropical Order, distinguished from the Gentian family 

 chiefly by the ovary completely divided into 2 cells, or more fre- 

 quently into 2 distinct carpels, whilst the style, or at least the 

 stigma, is entire. 



It is limited in Britain to the single genus PeriivinJde, but is repre- 

 sented in our planthouses by the Oleander (Nerium) from southern 

 Europe, the Allamandas, Dijoladenias, etc., from South America, Man- 

 devilla, and others, from tropical Asia. The closely allied Asclepias 

 family, which is entirely exotic, but includes the Periploca, Stapelias, 

 Hoyas, Stephanotus , etc., of our gardens and planthouses, differs chiefly 

 in the curious manner in which the anthers are connected with the 

 stigma. 



I. PERIWINKLE. VINCA. 



Herbs, with opposite, entire leaves, and blue, pink, or white flowers, 

 growing singly on axillary peduncles. Calyx free, deeply divided into 

 5 narrow divisions. Corolla with a cylindrical or almost campanulate 

 tube, and a flat, spreading limb, with 5 broad, oblique segments, 

 twisted in the bud. Stamens 5, enclosed in the tube. Ovaries 2, 



