326 RIDDLE: NOTEWORTHY LICHENS FROM JAMAICA 
MEGALOSPORA 
In an enumeration of Jamaica lichens in May, 1912, I described 
in Mycologia (4: 129) two new species of Megalospora: M. Cum- 
mingstae and M. jamaicensis. The following autumn, I had an 
opportunity to study all of the material of this genus, including a 
number of authentic specimens in the collection of Mueller-Argau, 
at the Boissier Herbarium, Chambésy, Switzerland. This led me 
to a detailed study of the principal species and as four of these © 
occur in Jamaica it will not be out of place to present, herewith, 
the results of this study. Two of the species are variable but 
with well-marked varieties, which have been recognized by 
various authors and are certainly worthy of varietal names. 
The genus Megalospora was established by Meyen and Flotow 
in 1843 (Nov. Act. Acad. Caes. Leop. Carol. 19 [suppl. 1]: 228), 
with M. sulphurata as the type-species. The species were included 
under Lecidea by Nylander; under Patellaria by Mueller-Argau; 
and under Heterothecium Sect. Psorothecium by Tuckerman. But 
in accordance with current ideas of the value of spore-characters 
in the classification of crustose lichens, Zahlbruckner (in Engler- 
Prantl, Nat. Pflanzenfam. I'*: 134. 1905) has revived Megalo- 
spora as a distinct genus, distinguished from the other Lecideaceae 
by the thick-walled, two-celled spores of large size. The common- 
est species is the variable M. versicolor (Fée) Zahlbr., of which — 
many of the other proposed ‘‘species’’ are synonyms or varieties. 
The following key and citations of species and synonymy will 
serve to summarize the results of my study of the American 
species and varieties of Megalospora. 
A. Growing on evergreen leaves................0.c2eeeee ee 5. M. premneella 
AA. Growing on the bark of trees. 
B. Spores straight (PLATE 21, FIGS. 9, 10). 
Cc. more or less Pena apothecia ee apes disk and 
traw-colored margin) 7 i S45 see 7 ee M. sulphureorufa 
cc. vane ashy or wanik: apothecia variously potest but the margin 
never strawecolored 665) Gc an ee ee (2. M. versicolor). 
sate we or oe contrasting with the fubsona. aeruginous, 
or ai cl Syd ik aah 2b. M. versicolor var. livido-cincta 
DD. Mar. us with the disk or nearly so, at least not pallid. 
E. pecan variously colored: carneous, fulvous, peta 
or black, regular in form, and rarely over 1.5 m 
2a. M. versicolor var. “aciovet 
