OF ARTS AND SCIENCES. 165 



XII 



CONTRIBUTION FROM THE GRAY HERBARIUM OF 

 HARVARD UNIVERSITY. 



DESCRIPTIONS OF NEW PLANTS COLLECTED IN MEX- 

 ICO BY C. G. PRINGLE IN 1890 AND 1891, WITH 

 NOTES UPON A FEW OTHER SPECIES. 



By B. L. Robinson. 



Presented by George Lincoln Goodale, June 15, 1892. 



Cleome Potosina. Herbaceous, two feet high: stem purplish, 

 striate, moderately branched, minutely glandular-pubescent, armed 

 at the nodes with pairs of small stipular spines: leaves trifoliate; 

 petioles minutely but densely glandular-pubescent, I-I2" inches in 

 length; leaflets ovate-lanceolate or narrowly rhombic, mostly acute 

 or acuminate at the apex, acute at the base, puberulent under a 

 lens and minutely ciliate, 1-1^ inches long, 5-8 lines broad: floral 

 leaves numerous, simple, lanceolate or ovate-lanceolate, subsessile, 

 4-6 lines in length : peduncles slightly puberulent or smooth, 

 about 9 lines long: sepals linear-subulate, acute, reflexed during 

 anthesis: petals spatulate, white, 5 lines in length, the blade 

 about equalling the slender claw: stamens variable, sometimes 

 very unequal in the same flower, some or all of them much exceed- 

 ing the petals: stipe of the ovary 6-10 lines long; capsule linear, 

 pointed at each end, moderately curved, smooth, but with a fine 

 longitudinal striation, 1^-1| inches in length, 1|— 2 lines in thick- 

 ness: seeds striate and muricate. — Tamasopo Canon, San Luis Po- 

 tosi, June, 1890 (n. 3538). Near the South American C. diffusa, 

 DC, but distinguished by the long stipe of the ovary, slender- 

 clawed petals, long stamens, and longer linear pods. It is also 

 near C. aculeata, L., but is amply distinguished by its long-stiped 

 ovary and much exserted stamens. 



Viola reptans. Rhizome short, bearing long fibrous roots: 

 stems numerous, glabrous, prostrate, 6-10 inches long, rooting at 

 the nodes: radical leaves broadly ovate, suborbicular, obtuse or 

 rounded at the apex, cordate, regularly crenate-serrate, smooth on 



