SUPPLEMENT. 
THE FAMILIES OF FLOWERING PLANTS 
By Cuarues Louis Poiiarp. 
CHAPTER XXV.—Continued. 
Family Bixaceae. Bixa Family. Contains 4 genera and about 20 
species, mostly tropical, but Amoreuxia, a mallow-like herb with large 
flowers, reaches our southwestern borders. The type of the family, 
Bixa, consists of the single species, B. Orellana. It is a small tree with 
broad, cordate leaves, somewhat suggesting those of a poplar, and clus- 
ters of pink flowers having very numerous stamens and a 2-lobed stig- 
ma (see Fig. 161). The fruit is a very spiny pod which splits into sev- 
eral valves when ripe; the seeds have a red, waxy coating, constituting 
the substance known as arnotto. This is an orange coloring matter 
used as a dye, and also to impart a color to butter. Since the discov- 
ery of a method by which it can be prepared synthetically by chemical 
processes, the value of arnotto has depreciated. 
Family Cochlospermaceae. Shell-seed Family. Contains two or 
three genera and abous 18 species, most of which are included in Coch- 
lospermum. They are shrubs or small trees with palmately-lobed, long- 
stalked leaves, and large yellow flowers in terminal panicles. The chief 
difference between this family and the preceding lies in the single, un- 
branched stigma and the downy seeds. Some species of Cochlosper- 
mum, which is exclusively tropical, yield a variety of gum, while others 
furnish a yellow dye somewhat similar, but inferior to arnotto. 
Family Koeberliniaceae. Junco Family. Consists of the single 
genus and species Koeberlinia spinosa, a remarkable shrub of ‘the Rio’ 
Grande region in Texas and Mexico. It is apparently quite destitute 
of leaves, the latter being minute and promptly deciduous. The smooth 
green branches and twigs taper to sharp spiny points; the small white: 
flowers, which are borne in umbel-like clusters, have 4 sepals, 4 petals, 
8 stamens, and a 1-celled ovary becoming a black berry in fruit. 
Family Violaceae. Violet Family. Includes about 15 genera and 
325 species, of wide distribution. Many of the tropical genera are 
shrubs or trees, but in temperate climates the plants are mostly peren- 
