1898 ] FLORA OF LOWER SONORAN AND ARID ZONES 131 
islands. Kcenigia, which has no special mechanism for distribu- 
tion, is the most widely distributed of all. 
FRANKENIACE. "4 
The Frankeniacee are typically halophytic plants, repre- 
sented in the new world as follows: 
FRANKENIA § TOICHOGONIA-COSMOPOLITA, six species in Chili on the 
coast and in the alkali regions inland. Of these /. grandifolia is abundant 
on the California coast, about salt lakes of southern California, and eastward 
to southern Arizona, New Mexico and northern Mexico, the inland type being 
var. campestris Gray. 
F. § ToICHOGONTIA-ISOLATA, three species: F. farinosa, about Cobija in 
northern part of desert of Atacama; F. ¢viandra, the Puna region, at 3500 to 
4000"; F. vidal, islands of San Felix and San Ambrosio, Chili. 
F. § BASIGONIA, two species: F. Palmeri, Lower California to San Diego 
bay; F. Jamesit, east foot of Rocky mountains in Colorado and western 
Texas, 
NIEDERLEINIA: J. juniperoides, salt steppes of Argentine ; nearly related 
to Frankenia § Basigonia. 
The Frankeniacee illustrate two features in the relation 
between the two regions of North and South America now under 
discussion. 
I. That a very recent distribution has taken place in the 
case of F. grandifolia, which belongs to a section notable for the 
number of closely related species. This distribution may be due 
to birds, since the plant is found so widely distributed inland 
and at a considerable height above the sea (1000™). 
2. That F. Palmeri, F. Jamesii, F. triandra, and others, and 
NMiederleinia juniperoides are isolated species, which we may regard 
as remnants of a previously widespread development; and there- 
fore no interchange between the regions occupied has occurred 
under present geological conditions. 
CHENOPODIACE. 
_ fhe Chenopodiacee should be considered in this con 
“ For detailed discussion of the geographical distribution of the Frankeniacez see 
Engler’s Jahrb. 24: 394. 1897. 
nection, 
