60 THE FLORA OF THE ALPS 
seeded follicles; seeds often with a tuft of silky hairs; 
leaves opposite, entire. A large order, chiefly of tropical 
and sub-tropical trees and shrubs with a milky juice; the 
European species are very few; none are alpine. 
1. VINCA, L. 
Stem decumbent; flowers large, solitary, axillary, blue 
or white; style terminating in a pencil-like brush. 
V. minor, L., Lesser Periwinkle; shady places, fre- 
quent. V. major, L., Larger Periwinkle; Pyrenees, 
naturalised in Southern Switzerland. 
Order LIV.—ASCLEPIADE. 
Flowers regular; calyx 5-toothed; corolla 5-lobed; 
stamens usually 5, united into a column round the stigma ; 
pollen coherent into a pollinium in each anther-lobe ; ovary 
2-celled, the carpels connate above; seed-vessel a pair of 
follicles, with numerous seeds clothed with silky hairs; 
leaves opposite, entire. A large order, chiefly of tropical 
and sub-tropical trees and shrubs with a milky juice; the 
number of European species is small; none are truly 
alpine. 
I. CYNANCHUM, L. 
Corolla rotate, 5-lobed, with five internal scales ; stigma 
apiculate. 
C. Vincetoxicum, R. Br. (Vencetoxicum officinale, 
Meench.); flowers small, yellowish-white, in axillary 
clusters of 2—3, stem erect, middle leaves cordate-ovate ; 
rocky woods, frequent. 
