﻿North American Polygonaceae. 53 



E. deflexum, with which species it has been confused, while the 

 manifestly peduncled narrowly-turbinate involucres debar it from 

 E. Hookeri. 



The type was found by Mr. Pringle on mesas near Tucson, Ari- 

 zona, May 2, 1884. Dr. Palmer collected the species at St. George, 

 Utah, in 1877. Number 430. 



II -A NEW GENUS OF POLYGONACEAE. 



The mountains of southern California have yielded many in- 

 teresting and peculiar plants ; some of these have been carefully 

 studied and properly disposed of, while others are still far from 

 their true systematic positions. The plant known as Oxytheca 

 Parishii is an illustration of the latter class. Leaving this species 

 out of consideration for a moment, we will have two distinct strains 

 in Oxytheca; the one extreme represented by Oxytheca luteola 

 and the other by Oxytheca perfoliata. All known members of the 

 group fall naturally into one or the other of the two divisions, save 

 O. Parishii, and to include this in the genus necessitates a third 

 subgenus and a great extension of the generic characters. The 

 latter alternative was resorted to by Dr. Parry, the author of the 

 species, but it seems to me unsystematic and confusing thus to 

 extend simple and clear-cut genera to such an extent. 



ACANTHOSCYPHUS. 



Ann 



wiry, forking scapes. Leaves basal, firm, denticulate with spinu- 

 lose teeth, dilated at the base. Bracts scale-like, ternate, 

 united at the bases, inclined to one side of the axes. Involucres 

 turbinate, truncate, on wire-like peduncles, with 18-20 hard 

 ribs which are prolonged into as many rigid acicular awns, 

 these surpassing the tube in length. Flowers 5-14, of two kinds : 

 staminate included: pistillate exserted. Pedicels subtended by 

 linear or linear-spatulate bracteoles. Calyx glabrous, segments 6. 

 Stamens 9, inserted at the base of the calyx. Embryo with a long, 

 curved radicle and accumbent cotyledons. 



A monotypic genus of southern California. 





Acanthoscyphus Parishii (Parry). 



Oxytheca Parishii Parry, Proc. Davenp. Acad. Sci. 3 : 1 76. 1 882. 

 In dry soil, San Bernardino Mountains, California, altitude 1,400 



meters, August 5, 188 1. Number 993. 



