488 PROCEEDINGS OF THE AMERICAN ACADEMY. 



and regularly serrate near the middle and relatively narrower than in 

 the nearly related M. frutescens, Ilemsl. I am unable to find M. arbor- 

 escens represented in any of the many recent Mexican collections. 



Calea Pringlei. Stems terete, 6 to 9 dm. high, in dried state striate, 

 dull brown, covered with a line spreading or slightly refiexed tomentum 

 of sordid color, and on young parts somewhat glandular; branches op- 

 posite : leaves broadly ovate to nearly orbicular, sessile, acute, coarsely 

 dentate (1 to l 1 teeth to the centimeter), rugose and scabrous-puberulent 

 above, paler green, reticulate veiny, and covered with a fine wdiite crisped 

 pubescence beneath : heads 8 mm. long, 3 mm. in diameter, about 10- 

 flowered, borne on pedicels 2 to 5 mm. long in opposite-branched com- 

 pound umbelliform cymes; scales of the cylindrical involucre pale 

 yellow, striate, very unequal, rounded at the tip, the outer sparingly 

 pubescent, small, not f'oliaceous nor even herbaceous ; pales erose, nearly 

 or (pate glabrous : corolla nearly glabrous but covered with transparent 

 globules, the proper tube slender and somewhat contracted to the summit 

 where it suddenly expands into the very short throat and deeply cleft 

 limb of i\\c lineai- segments : achenes slender, somewhat attenuate 

 toward the base, dark-colored with a violet tinge, appressed-pubescent ; 

 pappus scales about 1 mm. long, also purple-tinged. — Collected by C. G. 

 Pringle on mountains above Iguala, Guerrero, Mexico, altitude 1,230 m., 

 24 October, 1900, no. 8373. Type in herb. Gray. 



Calka Zacatecmiciii, Schlecht., var. calyculata. Involucre sub- 

 tended at the base by 2 or 3 herbaceous-tipped bracts; these usually 

 shorter than but sometimes exceeding the inner scarious scales. — 

 Mexico. Nuevo Leon in the Sierre Madre near Monterey, 0. G. Pringle, 

 no. 2221, 16 duly, 1888; also in the same locality, C. & E. Seler, no. 

 1080, 12 October, 1895. 



