1924] 
GRANT—A MONOGRAPH OF THE GENUS MIMULUS 113 
specimens in the М. inconspicuus group. М. primuloides is 
unlike any of the other species because of its scapose inflores- 
сепсе. It is а high mountain form common in meadows in the 
Rocky Mountain and Pacifie Coast states. 
The members of the second subgenus, Schizoplacus, differ 
from most of those in Synplacus not only in their separated pla- 
centae but also in their short pedicels and glandular-pubescent 
styles. The capsule shows considerable diversity in the different 
sections, varying from membranaceous to coriaceous. Except 
occasionally in Eunanus, Diplacus, and Tropanthus, it dehisces 
to the base only along the inner suture and part way or not at 
all along the outer. The species in Schizoplacus readily fall into 
six sections, Eunanus, Mimulastrum, (Enoe, Pseudoenoe, Tropan- 
thus, and Diplacus. 
Bentham proposed Eunanus as a genus but at Dr. Gray’s sug- 
gestion he later reduced it to a section, maintaining, with good 
reason, that several intermediate species invalidated it as a genus. 
The chief reasons for raising Eunanus to generic rank were the 
divided placentae, the dehiscence of the capsule, the pubescent 
style, the small nearly regular corolla, and the annual habit of 
most of the species. From the small annuals with nearly regular 
corollas there is, however, a gradual transition through M. brevi- 
pes and M. Bolanderi to the large leaves and distinctly bilabiate 
corollas of many members of the subgenus Synplacus. Although 
the capsule, as a rule, dehisces down the inner suture and only 
part way down the outer, in M. mephiticus and M. leptaleus 1% 
opens to the base along both sutures, as in the species in Syn- 
placus. The short pedicels and pubescent styles which have 
been used by some authors as of primary importance in separating 
Eunanus as a genus, are characters of doubtful generic value; 
besides both are found in several species in the subgenus Syn- 
placus. The division of the placentae to the base is not confined 
to Eunanus but is a constant character throughout the subgenus 
Schizoplacus. It is apparent then from the weakness of these 
characters that Eunanus cannot be recognized as a genus and it 
has been retained, accordingly, as a section. 
Mimulastrum.—This is a monotypic section based on M. mo- 
havensis, differing from Eunanus in its very short corolla-tube, 
