46 PROCEEDINGS OF THE AMERICAN ACADEMY. 
capitulis involucri squamis formae typicae simile ; foliis multo latiori- 
bus deltoideis 3-4 cm. longis 2-4.4! cm. latis apice et angulis 
inferioribus transverse divaricatis acutis. — Near Culiacan, Sinaloa, 
Mexico, coll. Schaffner (type, in hb. Gray). 
Evpatorium THyRsorpEuM Moe. ex DC. Prod. v. 150 (1836). Some 
years ago the writer (Proc. Am. Acad. xxxvi. 484) stated the belief 
that this plant was identical with EZ. guadrangulare DC. 1.¢. How- 
ever, subsequent study of more copious material and a re-examination 
of the type specimens in the Prodromus Herbarium at Geneva have 
shown conclusively that the two species are wholly distinct notwith- 
standing considerable habital resemblance. To H. thyrsoideum, which 
may be recognized by its roundish stem, more glomerate-thyrsoid 
inflorescence, and softer less stramineous involucral scales, the follow- 
ing specimens may be referred: Dr. Palmer’s no. 1048 (coll. of 1890) 
from Manzanillo, and his no. 1162 (coll. of 1891) from Colima, W. G. 
Wright’s no. 1355 from San Blas, Langlassé’s no. 650, collected on 
granitic soil at Cajinicuilar, alt. 300 m., in Michoacan or Guerrero, 
Baker's no. 2302, Volcan El Viejo, Dept. Chinandega, Nicaragua, and 
Barclay’s no. 2719 from Tiger Island, Gulf of Fonseca. 
EvPatoRIuM URTICAEFOLIUM Reichard, Syst. iii. 719 (1780). Agera- 
tum altissimum L. Spec. Pl. ii. 839 (1753). Hupatorium altissimum 
Murr. Syst. Veg.-ed. 13, 614 (1774), not L., nor Murr. lc. 613. 
ageratoides L. f. Suppl. 355 (1781). Kyrstenia altissima Greene, 
Leafl. i. 8 (1903). A consistent application of the rules of priority 
necessitates the reviving of Reichard’s name for our common and attrac- 
E. urticaefolium, it is necessary to suppress the later Z. urticaefolium 
L. f. Suppl. 354 (1781). This, however, is no great misfortune, for 
This plant has borne many names, of which the earliest appears to be 
the hitherto obscure EZ. pauciflorum HBK. Noy. Gen. et Spec. iv. 120 
(1820). Very different from this is the type of Z. urticaefolium L. f, 
