THE AM1:RICAN botanist 23 



aspect tu the young plant, but later the main axi^ tlevelupes 

 rapidly and overtops the earlier sparsely floriferous branches:, 

 beconiinj^^ ()-15 (hn. high (according to soil and moisture) : 

 stems rather blender, greenish but tinged with red, pubescence 

 thin, of two kinds, — short soft hairs and some stiller whit- 

 ish bristles ; leaves numerous, from linear to narrowly oblong, 

 5-1 3 cm. long, entire or sparselv denticulate, with ])ubescence 

 similar to that of the stem: intiorencence a crowed cor\nil)i- 

 form raceme, becoming typically racemose in age, pubescence 

 as of the foliage but denser and the hirsuteness more pro- 

 nounced especiallv upon the calyx lobes: calyx-tube slender. 

 8-lJ cm. long (in average specimens about 10) : calyx lobes 

 about 3 cm. or approximately one-third as long as the tube; 

 petals a clear fine yellow, broadly obcordate, more than 3 cm. 

 long, scarcely changed in diving: stamenL> and style ec|ualling 

 the petals, ovary short, the capsules in age only 3-3 cm. long. 



This handsome species is a hear relative of O. Jamesii 

 T. & G. from which its precocious crown branches, its strict, 

 >lender central stem, its calyx-tube, its compact inflorescence 

 of handsome unchanged flowers (corolla often 7-8 cm. across) 

 and its relatively short capsule seem to distinguish it. 



The type was secured by Willard N. Clute in the Navajo 

 Indian Reservation, in Arizona, in July. 1919, at War-God 

 Si)ring. on Navajo Mountain, at an altitude of about 7,000 

 feet and is his No. 4. Mr. Clute notes that it occurs on both 

 dry and moist ground 



In 1920 Mr. Clute secured at the Tuba Oasis, Painted 

 Desert. Arizona, an Oenothera (No. 102) that somewhat 

 resembles it but prohablv mav best be referred to O. Hookeri 

 because of its short calyx-tube and its less noticeable puhe- 



