DISTRIBUTION OF TRIBES. 447 
five to a genus, whilst in Helianthoidex the average is about eight, 
in Anthemidee above sixteen. It differs from Helianthoidee in 
the absence of any pales to the receptacle, and most frequently 
in the involucre approaching more to that of Senecionide: or of 
Anthemidez, in the pappus either of distinct equal scales or re- 
duced as in Anthemides, or passing almost into the sete of Sene- 
cionidez, in the shape of the achenes and in the greater fertility 
of the florets. Sterile disk-florets with undivided styles, charac- 
teristic of three considerable subtribes of Helianthoidez, are only 
known in the somewhat anomalous genus Blennosperma among 
Helenioidee ; and sterile ray-florets, not unfrequent in the 
former, have only been observed in Gaillardia among the latter, 
The geographical distribution is nearly that of Helianthoidez, but 
more strictly American, and chiefly western or extratropical ; only 
three species out of near 300 are known in the Old World, of 
which two are S.-Afriean, and one, identical with a S.-American 
one, is Australian. 
The tribe consists of four very natural subtribes, Beriee, Fla- 
veriee, Tagetinee, and Euhelenica, besides four more distinct 
genera technically united as a fifth subtribe under the name of 
Jaumiee. 
The subtribe Beriee, about 110 species in 30 genera, is the 
most characteristic of the tribe (although for the latter the name 
of Helenioidez has been adopted as having the right of priority) 
in structure as well as in geographical range. The Beriez are 
indeed throughout so eminently W.-American, that very little 
special mention need here be made of separate genera: 26 out 
of the 29 are found in the Mexican region (if we include 
California) ; three of these (Chenactis, Hymenopappus, and Pala- 
foxia) extend rather more eastward in N. America; one only 
(Schkuhria) extends into E. tropical S. America ; four ( Lasthenia, 
Bahia, Villanova, and Blennosperma) are represented in Chili by 
identical or nearly allied species. Of the three genera not 
yet observed in the Mexican region, one (Zhymopsis) is not 
far removed from it, being an insular form limited to Cuba, the 
two others (Closia and Amblyopappus) are Chilian, and may yet 
appear in the northern hemisphere. 
The genus Flaveria, seven species, with the closely allied mono- 
typie Sartwellia, belongs to the same W.-American region as the 
Beriex, extending from Chili to Mexico and Florida ; one species, 
either identical with or closely representative of the commonest 
LINN. JOURN.—BOTANY, VOL. XIII. 2 K 
