Plantae novae Mexicanae a D A. Purpus collectae. 319 
Possibly this is the H. caerulea of Biolog. Cent. Am. from the same 
region. 
Mexico: Collected near Orizaba, growing on rocks. No. 1251. 
20. Flourensia ilicifolia T. S. Brandegee, I, c., p. 238. 
Shrubby, 1,5 m high, the brown puberulent stems branched: leaves 
alternate, glabrous, ovate, spinulose-dentate, thick in texture, with stout 
midnerve, 2 cm long, 1 em wide, cuneate into a petiole 3—6 mm long: 
heads 1,5 em high, terminating the branches, eradiate: involucral scales 
in 3—4 rows, thick, linear-oblong, 6 mm long, 2 mm wide, obtuse, 
puberulent, the lower ones bract-like upon the peduncle: outer paleae 
of the receptacle resembling the involucre, indistinctly striate; inner 
paleae scarious and bifid at apex: corolla tube short: marginal akenes 
triquetrous; disk akenes flattened, all white-villous with long hairs: pappus 
two persistent stout scales widened to the base, with or without a small 
intermediate awn. 
Mexico: Collected near Parras, Coahuila. No. 1150. 
21. Bidens alpina T. S. Brandegee, l. c., p. 239. 
Annual, the few spreading stems sparingly hirsute-pubescent, 2—6 cm 
long: leaves pinnate, the blade 1 cm long or less and of greater width; 
pinnae 1—2 pairs, incised or entire, glabrous: petioles 5—15 mm long: 
heads on pubescent peduncles 2—3 cm long. 5 mm high and 8 mm wide 
ineluding the short quadrate, yellow ray: involucre double, the onter of 
five linear, slightly spatulate bracts, ciliate; bracts of the inner involucre 
ovate-lanceolate: akenes 7 mm long, nearly smooth; awns none or two 
varying from 1 mm long to rudiments, cornecous and not barbellate. 
This is a small species with short stems nearly prostrate and rather 
inconspicuous flowers. 
Mexico: Collected on Popocatepetl, growing in gravelly soil above 
timber-line. No. 1684. 
Achaenipodium. Nov. Gen. Compositarum T. S. Brandegee, I. c., p. 239. 
Capitula discoidea. Involucrum campanulatum, bracteis 2 —3-seriatis 
angustis herbaceis, exterioribus brevioribus. Receptaculum convexum 
bracteis complieatis flores amplectentibus onustum. Corollae tubulosae, 
limbo cylindraceo apice 5-fid. Antherae basi auriculis minutis sagittatae. 
Styli rami obtusi breviter appendiculati. Achaenia a latere compressa, 
margine ciliata, basi in stipitem contracta. Pappi aristae 2 setiformes, 
squamellis intermediis 0. Frutex? Folia opposita, petiolata, serrata. 
Capitula in paniculam corymbosam disposita. Corollae flavae. 
Achaenia stipitata iis Podachaeni simillima. 
` 22. Achaenipodium discoideum T. S. Brandegee, l. c., p. 239. 
Stems erect, striate, hirsute pubescent: leaves lanceolate, long-acu- 
minate, 10—14 em long, 2—3 cm wide, serrate with salient teeth, pinn- 
ately veined, the light-colored midnerve large and prominent, lighter- 
colored and hirsute-pubescent below, pubescent and darker green above: 
petiole 5—7 mm long, slightly broadened at base: inflorescence cerym- 
