192 SOUTH AFRICAN BOTANY 
Britain. Several species of Linaria occur in South 
Africa. Pentstemon is cultivated for its flowers and 
has a staminode in place of the fifth stamen. Veronica 
has 2 stamems only and 4 petals. Nemesia has a 
spurred corolla and the upper lip is 4-cleft.—It is pecu- 
har to South Africa but is much cultivated in England. 
Halleria has a nearly regular corolla (H. lucida is the 
‘Fag. 107.—Antirrhinum (Snapdragon). 
I. Vertical Section of Flower, II. Floral Diagram. 
White Olive). Harveya is a parasite with very showy 
flowers. Striga is a partial parasite, 
159. N. O. Compositae.—This is the largest order of 
flowering plants comprising over 11,000 species, more 
than 10 per cent of the total number of species of 
Phanerogams. The characters of the Order are so well 
marked that it is the easiest of any to recognize; on 
the other hand the determination of the genera is a 
matter of great difficulty. 
The plants are herbs, shrubs, or trees and have every 
variety of vegetative habit. 
