316 PROCEEDINGS OF THE AMERICAN ACADEMY. 
a ray and envelops the ray-achene by its thin infolded usually ciliate alar 
portions. The achenes are glabrous and crowned with a shallow callous 
cup, but otherwise pappusless. 
Although thus clearly marked, the species of this genus have from 
habital similarities been much confused with those of Subazia, Galinsoga, 
Melampodium, and Spilanthes. The following synopsis, drawn up during 
the study of the two new species here proposed, may therefore be found 
useful in showing the present status of the group. 
* Heads rermuiel pedunculate, racemose, relatively large (including the rays 1.6 
cm. iameter): rays about 12, conspicuous, pale yellow with more or 
less et roseate tinge: scales of the involucre ciliolate, otherwise glabrous: 
weak aquatic essentially glabrous perennials. 
+ Leaves slender-petioled. 
1. J. petiolaris. Sabazia glabra, Wats. Proc. Am. Acad. xxiii. 277. 
— Shallow water, pine plains, base of the Sierra Madre, Pringle, no. 
1295. The involute involucral scales enveloping the ray achenes clearly 
show this plant a Jaegeria. The transfer of Dr. Watson’s name glabra 
to Jaegeria is rendered undesirable by the varietal use of this designation 
under J. hirta by Mr. Baker in the Flora Brasiliensis as mentioned 
below. 
+ + Leaves sessile, amplexicaul. 
2. J. purpurascens. Decumbent stem simple or sparingly branched, 
purplish, glabrous, leafy: leaves oblong-lanceolate, acute, sessile by a 
elasping base, entire, glabrous, 1.4 to 2 em. long, 3 to 4 mm. wide: pe 
duneles terete, purplish, 3 to 4.2 em. long, puberulent near the summit, 
borne in the upper axils: disk 8 mm. in diameter, hemispherical, at 
length somewhat conical: rays 11 to 13, linear or narrowly oblong, 
purple, 6 mm. long: bracts of the open flattish involucre uniseriate, ovate, 
acute, strongly ciliate at the broadest involute part, green and glabrous 
dorsally: disk-flowers numerous; corollas pale yellow, 2 mm. long, gla- 
brous except for a tomentulose ring at the base of the tube: achenes 
glabrous, 1.7 mm. long, crowned with a narrow callous ring otherwise 
ealvous: ligules pale-yellow, shading to deep purple at the tip, 5 mm: 
long, 1.8 mm. broad. — Collected in shallow water near Durango, Mex- 
ico, by Dr. Edward Palmer, November, 1896, no. 805 (distributed as 
ia glabra). 
* * Heads solitary and snes (J. prorepens) or more often terminal in the forks 
_of the stem, or, when several, borne in leafy cymes: more or less pubescent 
- plants of muddy shores oF drier habitat: rays — or white. 
