302 NATURAL HISTORY OF PLANTS. 
The forty genera’ united in this family include about four hun- 
dred and fifty species, all belonging to the warmest regions of the 
globe. They extend in Africa to the Cape of Good Hope, and are 
not found farther north in America than Mexico. The family ceases, 
moreover, at Chili, and at one part or another of Central China and 
Japan. It is neither represented in Europe, nor in the United States. 
The two series of Papayee and Lacistemee are only represented in 
America; those of the Calanticee and Pangiee only in the Old 
World. This only possesses about a hundred and thirty species of 
Bivacee ; the other three hundred and twenty species being American. 
There are only American species in the genera Biva, Perdiscus, 
Letia, Samyda, Eucerea, Lunania, Tetrathylacium, Ryania, Kuhlia, 
Banara, Azara, Abatia. The genus Osmelia is peculiar to tropical 
Asia; Idesia to Japan; Dovyalis, Trimeria, Ludia, Aphloia, Pyramido- 
carpus, Dissomeria, Asteropeia, Calantica, Byrsanthus, Kiggelaria, and 
Rawsonia are peculiar to tropical or subtropical Africa, continental 
or insular; Streptothamnus, to Australia. As common to the two 
Worlds, but more abundant in the New, we find Oxcoba, Xylosma, 
Guidonia, Homaliuim, Turnera, and Cochlospermum. Flacourtia and 
Scolopia, natives of the old continent, are found in Asia, Australia, 
and Africa. | 
The characters common to all the Privaceæ are not numerous ; we 
can only cite as constant, or nearly so, the woody consistence 
of the stem,’ the parietal placentation, the indefinite number of the 
ovules, the presence of a fleshy albumen. In this, Brvacee singu- 
larly resemble the 7i/iacee and Terastremiacee, whose ovary cells 
are far from being always complete ; and as the preefloration of their 
calyx is variable, it may be said that they represent the parietal 
placentation of the Z7i/iacez when their calyx is valvate, and of the 
Ternstræmiaceæ when it is imbricated. At the same time, the series 
with free ovaries bave numerous points of contact with the Cistacee 
nearly allied to Cochlospermee, and only differ from them by their 

1 Besides those which are doubtful, in which 2 Oxtver (Stem. in Dicot., 6) has studied the 
is included Tachibota ( Guian., 287, t. 112) doubt- organization of the wood in Bixra Orellana, and 
fully ascribed to Bivacea, by ENDLICHER (Gen., has pointed out the thick numerous medullary 
n. 5884), and which ScHREBER (Gen., n. 513) rays, the woody tissue consisting of elongated 
had named SaZmasia, but which seem separated cellules little thickened, and often with abrupt 
from this family, according to BENTH. & extremities. The mass is traversed by finely 
Hooker (Gen. 124). It is perhaps a Sa- punctured or radiated vessels, generally two or 
myda. three radial. 
