179 
It is at once apparent from an inspection of this table, that more 
than one-half of the genera are American, and of those found in 
the eastern hemisphere all are represented by species in the west- 
ern hemisphere. Out of a total number of 268 species in 16 
genera, 183 species are confined to the western hemisphere and 
85 species to the eastern. The larger number of species of the 
eastern hemisphere, numbering some 71, belong to three genera 
Calandrinia, Anacampseros and Portulaca. Broadly speaking, the 
order Portulacaceae is an American order, and is interesting to the 
botanist morphologically, as well as ecologically. There is no 
more interesting genus from an ecologic standpoint than the genus 
Latinum. . 
It will be seen, if the American species of this genus are ar- 
ranged geographically, that the greater number of well-defined 
species range from Cnili and Peru, where proportionally the greatest 
number of species is found, through Mexico where the genus is 
represented by at least 5 species to western North America to 
New Mexico and Texas. 
COUNTRY. : Number of Species. 
Chi "4 Bay CS ae we eee a ee oe ore ee we 6 
ROR, i ee oe oe Se Ware a ele 4S 2 
WERORNMIR i ais ae een tia ey idee I 
PME BION Ee SA ei ee eer i eRe 2 
scant CP ET AN Geet met ST aay cae eo mee Mo ce 5 
Ws TG NE ee a a eS ees 4 
Nu o Mek. 36 se ROR ES ae ee eae eo I 
ORS ae aie Bea ees pig ie A ee ele 2 
SO Oe ag es ee Se er I 
AMS DOS 3 Bes 8 GS es CRs Beer ee 3 
The greater majority of the species of the genus Zalinum 
range, therefore, along the backbone of the continent, and the 
Species are discovered in greatest abundance in Mexico and 
western South America. A few species are isolated, and are 
Separated from the main regiment as_ stragglers. 
teretifolium is one of these species, ranging over the eastern and 
Takaem 
central United States. From Prof. Thos. C. Porter, I learn that — oe 
in the Herbarium of Lafayette College there mee: specimens of : 
Talinum teretifolium collected in the following localities, in addition 
