OF ARTS AND SCIENCES. 285 
Notes upon the Tribes, ete.,— their Affinities and Geographical 
Distribution. 
The entire order of Ziliacee includes about 180 genera and 1900 
species, of which 50 genera and 230 species are found in the United 
States and northward; Mexico adds four genera and 40 species, and 
South America 26 additional genera and 58 species. The total of 
American representatives of the order is 80 genera and 333 species. 
At least 60 of these genera are peculiar to America, while only eight 
of the species are common to the Old and New World. The West 
Indies and all of South America to the east of the Andes are almost 
wholly destitute of species, the order being confined in that continent 
mainly to the western slope of the Andes, from Peru to Patagonia. 
Taking up the tribes in their sequence, the Allee are represented 
principally by a single genus, Allium, by far the largest and most 
widely distributed of all the genera of the order. It numbers about 
270 species, of which 220 are found in the northern temperate and 
warm regions of the Old World. No species occur in Australia, and 
probably none in tropical or Southern Africa. In the New World 
are about 50 species, mostly in the western United States, a very few 
Mexican, and a few in South America. Of the two other genera of 
the tribe, both small, Vectaroscordium belongs to the Mediterranean 
region, and Nothoscordum to the warmer portions of both western 
continents. The subdivisions of Allium, as a whole, are not satis- 
factorily defined, and a careful and thorough revision of this most 
difficult genus is still greatly needed. Some of the Old World sec- 
tions are not represented in America, and on the other hand several 
of our western groups are peculiar. The eastern A. tricocewm also is 
very distinct from all our other species, with apparently some near 
allies in Europe and Asia. 
The Gillesiee, a very remarkable tribe of Chilian plants, including 
half a dozen mostly monotypical genera, appear to be most nearly 
related to the Allie. 
The Millee are exclusively confined to the western portion of 
North and South America, only Androstephium ranging so far east 
as Kansas and Texas. The genus Jfilla must be limited to the one 
species MV. biflora, all the South American species that have been 
referred to it probably belonging to Leucocoryne, the southern coun- 
terpart ‘to the Californian Grodiea and numbering as many species. 
The genus Muilla (the name an inversion of Allium) is formed for a 
plant that has usually been placed with the Allee, but which has not 
