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THE GENUS SAVINIONA. 159 



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bordering the Mohave Desert, but is a smaller plaut, and has 

 abundant characters. 



Arabis Davidsonii, lyow perennial inhabiting moist 

 rocks, the short naked and scapiform flowering stems arising 

 each from the branch of a short compactly leafy caudex: 

 leaves oblanceolate-cuneate, 1 to 1% inches long, very narrow 

 below the middle, at apex acutish and there rarely with a sharp 

 tooth or two, commonly quite entire, of a light green and 

 wholly glabrous like every other part of the plant: flowers 



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subquadrate or more rounded, wingless, forming a single row 

 in the narrow subfalcate pod. 



Bishop's Creek, Inyo Co., Calif., July, 1911, Dr. A. 

 Davidson ; his n. 2728. These two new ones represent 

 extremely different types of so-called Arabis. 



The Qenus Saviniona. 



The genus Lavatera, to which certain botanists averse to 

 using their powers of discrimination have reduced Saviniona, 

 was established on malvaceous herbs much resembling Malva, 

 but differing from them as to the outer involucel subtending 

 the proper calyx. In Malva this is of two or three small 

 bracts that are deciduous. In Lavatera the involucel is a 

 firm persistent disk or shallow cup, but more or less deeply 

 three-cleft. Habitally the lavatera species of Continental 

 Europe are widely at variance among themselves, so widely 

 that the several genera that have been proposed will ulti- 

 mately be accepted, no doubt ; for the time seems pass- 

 ing during which men looked to nothing but calyx, 

 corolla and seeds for marks by which to delimit genera. 

 Botanists of the future will give more consideration to the 

 plant as a whole. 



