202 PROCEEDINGS OF THE AMERICAN ACADEMY. 
believed that few persons will be disposed to follow the older authors 
in uniting without distinction of name plants so conspicuously different 
in their foliage as L. tenuifolia and L. laevigata, yet on the other hand 
intergradation seems to be demonstrated and there are no differences 
of much taxonomic significance. To maintain the larger plantas a 
distinct species on the sole ground of its greater robustness, seems as 
undesirable as to suppress it altogether. 
Il. REVISION OF THE GENUS BARROETEA. 
BARROETEA Gray. (Clarissimo G. Barroeta doctori medicinae 
et professori scholae metallorum ad oppidum mexicanum San Luis 
Potosi dictum institutae ob amicitiam suam cum collectoribus botanicis 
doctoribus Parryo et Palmero petito eorum dedicata.)— Capitula medi- 
ocria 17—35-flora ; involucri campanulati vel turbinati squamis valde 
inaequalibus appresse imbricatis tenuibus costato-lineatis saepius at- 
tenuatis raro obtusis vel apice rotundati tisque ; receptaculo 
plano nudo. Corollae tubulatae glabrae pallidae ad insertionem fil- 
amentorum plus minusve constrictae, faucibus vix ullis, limbo breviter 
5-dentato. Antherae distinctae vel levissime connatae, apice in appen- 
dicem latam obtusissimam productae, basi rotundatae integrae. Styli 
rami clavellati vel apud speciem unicam valde sursum incrassati, paulo 
exserti, Achaenia valde obcomp anguste oblonga, margine sursum 
scabrata vel ciliolata, in facie exteriori vel uninervia vel conspicue uni- 
costata, in facie interiori 2~3-nervia vel -costata. — Proc. Am. Acad. xv. 
29 (1879), xvii. 206 (1882) ; Hemsl. Biol. Cent.-Am. Bot. ii. 102 (1881); 
Hoffm. in Engl. & Prantl, Nat. Pflanzenf. iv. Abt. 5, 142 (1890). 
Barroetia Hook. f. & Jacks. Ind. Kew. i. 276 (1893) ; Dalla Torre & 
Harms, Gen. Siphon. 528 (1905).— Herbae graciles annuae vel pe- 
rennes nonnunquam basi paulo lignescentes saepius ramosae foliosae 
crispe puberulae vel tomentellae rarius glanduliferae. Folia vel omnia 
opposita vel superiora alterna ovata petiolata vel sessilia crenati- 
vel argute serrati-dentata, apice et dentibus saltim posticis in appen- 
dices setiformes desinentibus. Capitula saepius in panicula laxiuscula 
foliaceo-bracteata disposita. 
Genus Brickelliae arcte affine et eae habitu, involucro, etc. simillimum 
differt dentibus foliorum setiferis et praesertim achaeniis valde obeom- 
pressis 5-6-costatis. 
Species hucusque cognitae 7 omnes mexicanae praecipue montanae et 
calciphilae locos umbrosos praeferentes, una (n. 1) excepta inter se 
arctissime affines characteribus quamquam saepe obviis tamen incertis 
et minus constantibus diagnoscendae. 
