58 STAND ley: a new genus of chenopodiaceae 



in this group of the Chenopodiaceae are of so little taxonomic 

 importance — being singularly uniform through all the genera 

 of the tribe — that the writer has no hesitation in making it the 

 basis of a new genus, named in honor of the discoverer. Its 

 characters are discussed below. 



ZucKiA Standley, gen. no v. 



Low erect shrubs, with a copious covering of whitish inflated trich- 

 omes. Leaves numerous, alternate, petiolate, the blades flat, entire. 

 Flowers dioecious, the pistillate ones sessile, solitary or in small glome- 

 rules forming short interrupted naked paniculate spikes, each flower 

 bibracteolate, the bractlets accrescent in age, united except for a small 

 aperture at the depressed apex, slightly inflated, thin, depressed 

 vertically, 6-carinate vertically, 2 of the keels broader than the others 

 and winglike; perianth none. Ovary depressed-globose; stigmas 2, 

 filiform, exserted, connate at the base. Utricle included in the 

 bracts, the pericarp membranaceous. Seed horizontal, the testa mem- 

 branaceous; embryo annular, surrounding the copious endosperm; 

 radicle centrifugal. 



Type species, Zuckia arizonica Standley. 



Zuckia arizonica Standley, sp. nov. 



Plants 1.5-4 dm. high, fruticose nearly throughout, copiously 

 branched, the branches slender, erect, striate, the older ones gray or 

 brown, the younger ones stramineous and densely furfuraceous; leaf 

 blades oblong-oblanceolate or spatulate-oblanceolate, or the upper- 

 most hnear-oblanceolate, 10-20 mm. long, 1.5-7 mm. wide, obtuse to 

 acutish at the apex, attenuate at the base to a short stout petiole, 

 thick and somewhat coriaceous, grayish-furfuraceous; pistillate spikes 

 much interrupted, divaricate, forming nearly naked panicles 5-12 cm. 

 long and 2-6 cm. wide; fruiting bractlets 4-5 mm. broad, densely 

 furfuraceous, the 6 keels acute, two of them usually 1-1.5 mm. wide 

 and winglike; utricle furfuraceous; seed orbicular, compressed, 2 mm. 

 in diameter, yellowish brown, dull. 



Type in the U. S. National Herbarium, no. 694799, collected at 

 Chalcedony Park (the Petrified Forest), eighteen miles southeast of 

 Holbrook, Arizona, October 15, 1897,' by Miss Myrtle Zuck (Mrs. 

 Walter Hough). Also collected at Adamana, Arizona, in early August, 

 1903, by Dr. David Griffiths, no. 5085 (Mo. Bot. Card. no. 46127). 

 The type is in mature fruit and the second specimen in flower. 



The genus Zuckia is a member of the tribe Atripliceae, subtribe 

 Atriplicinae, as defined by Volkens.^ It is difficult to tell to which 

 of the included genera it is most closely related. In the key given by 

 Volkens it would run to either Spinacia or Suckleya. Certainly 



2 In Engl, and Prantl, Nat. Pflanzenfam. 3^^: 62. 1893. 



