MALVACE, 111 
It includes about twelve hundred species,’ of which six-tenths 
belong to the Old World and the rest to the New. The number of 
genera belonging to the latter is much less considerable than those 
pertaining to the former; for America has only twenty-three 
genera which belong to it exclusively, while the Old World has 
forty-eight. | Consequently seventeen genera are common to 
both Worlds. To the Old World belong exclusively all the Za- 
siopetalee, Dombeyee, Helicterea, except the genus Helicteres; to 
the New World the small series Chiranthodendree.  Except two or 
three species, Lasiopetalee would even belong exclusively to Australia. 
Bombaceæ, Helictereæ, Buettneriee, and Dombeyee nearly all con- 
sist of plants of the tropical regions. Hermanniee, Hibiscee, and 
Urenee extend thence into the most temperate climates such as the 
Cape of Good Hope, Mexico, extratropical Australia, and the north of 
India and China. Jalvee and Malopee, are composed of the plants 
of the family found as far as the coolest regions of the globe, 
whether it be to the north or south of America, to the south of 
Australia in New Zealand (like Hoheria and Plagianthus), in Asia 
and Central and Northern Europe. They are, however, abundant in 
tropical regions since they form there, according to Humboldt, 
a fifth part of the vegetation® of the valleys. The proportion de- 
creases considerably in the temperate zone, since there is only one- 
fourth as much as the preceding.’ There is moreover here as in all 
the great families, types the diffusion of which is extreme: as 
Hibiscus which is found in all parts of the world, and which in 
America for example, occupies an area of ninety degrees in latitude. 
The Mallows are still more widely extended. On the contrary there 
are genera strictly limited to a small portion the globe, some 
tolerably numerous as to species like the series Lasiopetalee ; others 
are monotypes or reduced to a very restricted number. The 
small series of Chiranthodendree, represented hitherto by a single 
genus with two sections and two species, only exists in a very re- 
stricted part of the west of North America. Ju/ostyles, Dicellostyles, 

1 In 1846, LINDLEY (Veg. Kingd., 362, 564, ? Linpury (Veg. Kingd., 369) thinks doubt- 
370), more than fifteen hundred were counted: less that Sferculieæ are comprised in this valua- 
1000 for the Malvacee proper ; 400 for Buelt- tion. 
neriaceæ ; and, 125 for Sterculiacee. 3 The other numbers cited in the work of 
