OF AETS AND SCIENCES. 285 



Notes upon the Tribes, etc., — their Affinities and Geographical 



Distribution. 



The entire order of Liliacece includes about 180 genera and 1900 

 species, of which 50 genera and 235 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 Alliece 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, Nectaroscordium 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. tricoccum also is 

 very distinct from all our other species, with apparently some near 

 allies in Europe and Asia. 



The Gillesiece, a very remarkable tribe of Chilian plants, including 

 half a dozen mostly monotypical genera, appear to be most nearly 

 related to the Alliece. 



The Millece are exclusively confined to the western portion of 

 North and South America, only Androstephium ranging so far east 

 as Kansas and Texas. The genus Milla must be limited to the one 

 species M. bijlora, all the South American species that have been 

 referred to it probably belonging to Leucocoryne, the southern coun- 

 terpart to the Californian Brodicea 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 Alliece, but which has not 



