392 standley: north American amaranthaceae 



has resulted largely from an attempt to recognize in certain 

 tribes too large a number of genera, these based upon vegetative 

 or inconstant characters. 



The only monograph of the North American Amaranthaceae 

 is that of Uline and Bray, which appeared about 20 years ago 

 in the Botanical Gazette.^ The conclusions reached by these 

 authors need scarcely be modified now except for certain changes 

 of names necessitated by modern systems of nomenclature. The 

 species treated, however, included only a small part of those 

 found in tropical North America. Moquin had in 1849^ de- 

 scribed all the North American Amaranthaceae then known, in 

 his monograph of the whole family, but naturally many addi- 

 tional species have been discovered in the intervening 66 years, 

 about 155 species being known in North America at the present 

 time. Several of the tribes, particularly the Amarantheae, reach 

 their highest development on this continent. The family being 

 chiefly tropical, South America possesses a larger number of 

 species than North America. Many species are to be found 

 also in Africa and Australia, and a few in Europe and Asia. 



The following arrangement of tribes and genera is proposed 

 by the writer for use in a monograph of the family now in prep- 

 aration for the North American Flora: 



I. Celosieae. Differentiated from all other tribes of the family 

 by the presence of 2 or more ovules in the ovary, instead of a single 

 ovule. Only 6ne genus, Celosia, occurs in North America, being repre- 

 sented by 6 species. 



II. Amarantheae. Five genera are represented in North America: 

 Lagrezia, Chamissoa, Amaranthus, Acnida, and Acanthochiton. . 



1. Lagrezia has not been reported previously from outside of Africa, 

 nor has it always been referred to the Amarantheae. Moquin placed 

 it in this tribe, but Dr. Schinz in his treatment of the famly in Engler 

 and Prantl's NaturUchen Pflanzenfamilien considered it a synonym of 

 Celosia. There is no doubt that Lagrezia is closely I'elated to that 

 genus, but it seems to be quite distinct in having only a single ovule 

 in the ovary. If the Celosieae and Amarantheae are to be maintained 



2 19: 267-272. 1894; 20: 155-161, 337-344, 449-453. 1895; 21: 348-356 1896. 



3 In DC. Prodr. 13^: 231-424. 



