THE VIOLET FAMILY 261 



plant is probably deciduous even at sea-level. It certainly is 

 so in the Christchurch Gardens, where it grows only a few 

 feet above high-water mark. 



The under-surface of the leaf of the var. ribifoUa, is 

 covered with a down of stellate hairs. As this variety is only 

 found in drier localities, the obvious value of this covering is 

 to enable the leaves to retain their moisture. G. Lyallii has 

 hairs only on the veins. The two forms are never found 

 growing together ; and this discontinuous distribution, as well 

 as other characters, seems to show that they are specifically 

 distinct. 



The inner-bark of this tree has the same lace-like 

 appearance as that of Hoheria. 



Violaceae. 



The Violet Family. 



Distribution. — Family of about 300 species, found both in temperate 

 and tropical regions. The temperate forms are usually herbaceous, while those 

 of warmer climates become shrubs or trees. The Violet and Pansy are well- 

 known garden flowers. 



Key to the Genera. 



1. Flowers irregular. Viola, p. 261. 

 Flowers regular. 2 



2. Flowers dicecious. Melicytus, p. 264. 

 Flowers perfect. Hymenauthera, p. 266. 



Genus Viola. 



Three New Zealand species, all endemic. Petals unequal, the lower one 

 spurred. Capsule with three valves. In most of the species of Viola, the 

 ordinary flowers set no seeds. The j)lant, however, produces, at a later stage, 

 green-coloured, sell-pollinated flowers, which seed freely. 



Viola filicaulis {The Thread-like Violet). 



So-caUed from its slender, thread-like stem, which is prostrate. Leaves 

 alternate, shining, heart-shaped. Flowers yellowish. Abundant in both 

 islands. Ordinary flowers Nov. -Dec. ; cleistogamic flowers Jan. and Feb. 



