OF ARTS AND SCIENCES. 29 



BARROETEA, Nov. Gen. Eupatorinearum. 



Involucrum (15-25-florum) floresque Ku/mice et Brickellice. Ache- 

 ma oblonga, compressa, binervia, nervis marginalibus tenuibus ciliolatis, 

 lateribus nee eostatis nee striatis, callo basilari magno. Pappus simplex, 

 e setis capillaribus uniserialibus pauciusculis (12-20) aequalibus rigidu- 

 lia e disco epigyno achenio angustiore. — Planta) Mexicans, graciles; 

 foliis plerisque oppositis ovatis petiolatis dentatis, dentibus saepe aris- 

 tatis, pube minuta. 



Barroetea setosa. Herbacea, ramosissima; radice ut vkletur 

 perenni ; foliis mernbranaceis grosse argute serratis vel duplicato- 

 dentatis, dentibus fere omnibus promisse aristatis ; capitulis in axillis 

 brevi-pe-dunculatis folio fulcrante plerumque superatis ; achenio ad 

 margines hii to-ciliato ; pappi setis crebre serrulato-seabris. — Moun- 

 tains southeast of the city of San Luis Potosi. No. 353. 



Barroetea subuligera. Fruticulosa, corymboso-ramosa ; foliis 

 crenato-serratis, acumine saepe dentibusque posticis subulato-mucrona- 

 tis ; capitulis longe pedunculatis corymbosis (char, pranced, e Schauer); 

 involucro bracteis magis atteuuatis ; achenii marginibus ciliolatis ; 

 pappi setis tenuissime scabris. — Bulbostylis subuligera, S. Schauer in 

 Linnsea, xix. 718. Zimapan, Mexico, Aschenborn. 



It was evident from the published description of Schauer's Bulbostylis 

 subuligera, with its flat achenia, that it was a congener of the plant 

 scantily collected by Parry and Palmer, and distributed as No. 353. 

 I am indebted to Prof. Eichler of Berlin for the communication of a 

 capitulum of Ascheuborn's plant, which confirms the determination. 

 These two plants want the technical character both of the Ageratece 

 and of the Ade?ios/ylece, as arranged by Bentham (which subtribes 

 should therefore be merged and distributed into mere sections), and 

 they form a well-defined genus, which, at the instigation of the collectors 

 of one species, I dedicate to their good friend, Professor Bairoeta, of 

 the School of Mines at San Luis Potosi, a competent naturalist, who 

 has devoted considerable attention to the botany of the province. 



Brickellia hymenochl-Sina. Herbacea, minute puberula; caulo 

 simplici pedali 10-14-phyllo apice nudo corymboso-oligocephalo ; 

 foliis oppositis ovatis vel deltoideo-oblongis nunc subcordatis obtusis 

 crenato-serratis vel integriusculis petiolatis; capitulis pedicelhitia 

 (ultrasemipollicaribus) ; involucro lato-campanulato circa 30-floro 

 pauciseriali ; bracteis plerisque tenuiter membrauaceis scariosisque 

 purpureo tinctis ovalibus vel spathulatis acuminatis cum mucrone 

 gracili, extimis paucis laxis lanceolato-subulatis paruui hcrbaceis; 



