458 PROCEEDINGS OF THE AMERICAN ACADEMY. 
hirtellous: inflorescence cymose-paniculate: corolla white or purplish, 
campanulate; lobes revolute, externally pubescent: fruit covered with 
rather short uncinate-hispid bristles. — Nov. Gen. & Spec. iii. 337 ; Hemsl. 
Biol. Cent.-Am. Bot. ii. 65. — Guanajuato, Dugés ; Valley of Mexico, 
Pringle, no. 6518; Jalisco, Rio Blanco, Palmer (collection of 1886), no. 
753; Tepic, near Santa Teresa, Rose, no. 2151; Orizaba, Seatom, no. 
127. A specimen from Caliacan, Palmer (collection of 1891), no. 2777, 
may be doubtfully referred here. 
Var. glabratum, Nearly glabrous throughout, otherwise as in the 
typical form. — Collected by E. W. Nelson on the west slope of Mt. 
Zempoaltepec, Oaxaca, altitude 2370 to 2460 m., 5 to 13 July, 1894, 
no. 983. 
Var. platyphyllum. Similar to the species proper, but with 
broader oblanceolate or oblong-spatulate leaves, 1 to 2 cm. long, 2 to 
6 mm. wide, abruptly cuspidate-acuminate at the rounded summit, not 
unfrequently hirtellous-puberulent beneath and occasionally hirsutish 
bove. — Chiapas, near Christobal, altitude 2150 to 2704 m., 18 Sep- 
tember, 1895, E. W. Nelson, nos. 3165, 3200; Oaxaca, Sierra de San 
Felipe, altitude 3075 m., 28 June, 1894, Pringle, no. 5663; vicinity of 
Yolontepec, altitude 1700 to 2150, 15 to 20 July, 1894, Welson, no. 714; 
Colima, 9 January to 6 February, 1891, Palmer, no. 1407. 
* * Leaves in whorls of four: the angles of the stem aculeolate-hispidulous : 
: owers cymose 
4. G. pretermissum, Greenm. Stems slender, 3 to 4 dm. long; 
ascending from a perennial base, slightly hispidulous: leaves linear-lau- 
ceolate to linear, 8 to 14 mm. long, 1 to 3 mm. broad, acute, margins revo 
lute, upper surface often slightly hispidulous, the lower glabrous: flowers 
terminating the lateral branches in subtrichotomous cymes. — Proc. Am. 
Acad. xxxii. 306. — Federal District, Pringle, no. 6596. 
* * * Leaves in fours: hirsute-pubescent to nearly glabrous plants, not retrorsely 
aculeolate-hispid: flowers terminating the stems and branches in rather close, 
or dichotomously branching cymes. : 
+ Flowers paniculately disposed in dichotomously branching leafy cymes: ner 
nate bristles of the fruit subappressed. 
5. G. Pringlei. Stems 3 to 5 dm. high, erect or ascending from 4 
perennial base, covered with a spreading hirsute pubescence: leaves ™ 
fours, the uppermost opposite, 1-nerved, oblong-elliptic to oblong-lanceo- 
late, 4 to 12 mm. long, 1 to 5 mm. broad, submucronate, narrowed at the 
base, hirsute-pubescent upon either surface: flowers sessile or short 
pedicelled: corolla whitish: fruit about 1.5 mm. in breadth, covered with 
