462 PROCEEDINGS: BOSTON SOCIETY NATURAL HISTORY. 
Entyloma compositarum Fail. 
Entyloma compositarum Farl., Bot. Gaz., 8 : 275. 1883. 
Exsiccati: Entyloma compositarum Farl., on Ambrosia trifida, Ell. & Ev., 
N. A. Fungi, 2429 b; on Aster Novi-Belgii , Seym. & Earle, Econ. Fungi 
Clinton Ust. Supp., C 16; on Aster puniceus, Ell., N. A. Fungi, 1492 a; on 
? Eupatorium ageratoides, Seym. & Earle, Econ. Fungi Clinton Ust. Supp. 
C 17 ; on Lepachys pinnata, Seym. & Earle, Econ. Fungi Clinton Ust. Supp.’ 
C 18; on Rudbeckia laciniata, Ell. & Ev., N. A. Fungi, 2429 a. 
Sori in leaves, small, angular, about 1-2 mm. in length, usually 
abundant and more or less confluent, forming spots whitish or yel¬ 
lowish on the under side and darker often purplish on the upper; 
spoies chiefly hyaline, ovoid to spherical or occasionally polyhedral, 
smooth, thin walled, chiefly 9-14 p in length; usually with evident 
hypophyllous outgrowth of conidia which are fusiform or slightly 
clavate, often curved, about 15-20 p x 2-3 p. 
Hosts: Ambrosia artemisiaefolia , Mass., Me.; A. psilostachya, 
Kans., YV isc.; A. trifida, D. C., Ill., Mo., Wise.; Aynbrosia sp., Minn., 
Ohio ; Aster cordifolius , Mass.; A. Novi-Belgii, Mass., Me.; A.pani- 
culatus , Wise.; A. puniceus , Mass., N. H. (type) ; Aster sp., N. 
Brunsw. ; *Bidens chnjsanthemoides , Kans.; Erigeron elatus, 
Wash.; L. Bhiladelphicus, N. Dak., YYisc.; ? Eupatorium agera¬ 
toides, Ill.; * Gnaphalium sp., Ala.; * Helenium autumnale, YVisc.; 
* Heterotheca Lamar ckii, Kans.; *Lacluca Cayiadensis, Minn.; 
Lepachys pinnata, la., Ill., Minn., YVisc.; Rudbeckia laciniata. Mo.’ 
Ohio; ' /Senecio aureus. Neb., YVisc.; S. aureus var. Balsamitae, 
Kans.; * Silphium integrifolium, YVisc. 
It is difficult to classify the Entylomas on Compositae on any per¬ 
fectly satisfactory basis, The type described by Farlow on Aster 
puniceus has hyaline, thin walled spores and is usually accompanied 
by conidia. On the Ambrosia hosts there occurs besides this type 
another, included here under Entyloma polysporum, which "has 
larger thick walled and more deeply tinted spores and is usually 
without sporidia. A fair, but not extreme, illustration of the differ¬ 
ences of these two species is shown by specimens (a) and (b) of 
Ellis’ N. A. Fungi, no. 1492. The form listed on Eupatorium 
ageratoides has spores much like Entyloma polysporum while 
the son are like Entyloma compositarum. It has been placed 
under the latter species questioningly, as it may deserve independent 
