10 PROCEEDINGS OF THE AMERICAN ACADEMY. 
* * Whole plant canescent-tomentose : leaves linear, entire, 
20. T. candidissima, Gray. Very white-woolly, 4 to 6 inches 
high, densely leafy below : leaves 1 to 13 inches long, sessile by a sheath- 
ing base: peduncles solitary, terminal, naked: heads homogamous: 
involucral scales lanceolate, acute: pappus long. — Proc. Am. Acad. xv. 
39.—On ashy soil, Angostura, San Luis Potosi, Parry & Palmer, no. 
510. Not since rediscovered. 
~~ Subgenus PseupoTRIDAX. Scales of the involucre sub-uniseriate : 
achenes merely papillose-puberulent or glabrescent: scales of the pappus 
obtuse or obtusish, laciniately bordered: anomalous species connecting 
this genus with Galinsoga. 
en 21. T. (?) dubia, Rose. Decumbent or procumbent pubescent 
herb ; stems about 2 feet long: leaves ovate, serrate, acutish, petiolate : 
heads subracemose or subcorymbose, 6 lines in diameter: involucral 
scales very few, about 5: ray-flowers with short golden yellow 3-toothed 
ligules. — Contrib. U. S. Nat. Herb. i. 337, t. 33. — Along river bottoms, 
Colima, Palmer, no. 1173; also in lowlands near San Blas, Tepic, 
Lamb, no. 609. 
Species (doubtless of Eutridax but otherwise) of doubtful affinities: not seen 
the writer 
22. T. Ehrenbergii, Schz. Bip. “Stem herbaceous, elongated, 
climbing, sulcate, sparingly pilose, trichotomous: leaves rhomboidal, 
slender-petioled, acuminately serrate, 3-nerved, above sparsely pubescent, 
below pilose upon the nerves: head solitary, terminal, many-flowered : 
_ involucre campanulate: scales scarious, laciniate on the margins: chaff 
scarious, trifid, costate, mucronate: flowers of the disk campanulate, 
pilose, ciliated on the margin: pappus-scales fimbriate, shorter than the 
sericeous achene.” — Leopoldina xxiii. 6. — “Chinantla, Liebmann, 20. 
598. Leaves 20 lines long, 9 lines broad.” 
IL —SYNOPSIS OF THE MEXICAN AND CENTRAL 
AMERICAN SPECIES OF THE GENUS MIKANIA. 
MIKANTA, Willd. (Dedicated to Professor Joseph Gottfried Mikan, 
of Prague, born 1743, died 1814.) — Cylindrical involucre of four e 
concave obtuse or acute equal or subequal scales, sometimes with a shorter 
external fifth scale. Receptacle small, naked. Flowers 4 (in M. punetata 
“7”), tubular, with campanulate throat and 5-toothed limb. Anthers 
appendaged at the apex, obtuse or truucate at the base. Style-branches 
long, filiform-clavellate. Achenes 5-angled, without intermediate ribs, 
