126 Trans. Acad. Sci. of St. Louis. 
The ancestral type was probably melittophilous and has 
produced a most numerous set of species in competition with 
one another for the attention of bees. Competition between 
allied species is most severe. As a result of this strong 
competition we have many forms which have so _ far 
changed from the original type that they no longer come 
in competition for bees, but have become adapted to other 
kinds of insects. In the Fertilization of Flowers, 471, 
Miiller says: ‘‘ Delpino considers Mentha and Coleus Lour., 
degraded forms of the Labiate type; he, however, gives no 
reason for thinking them to be such, and not rather less 
specialized forms, differing less from the common ancestors 
of the Lubiates.’’ Mentha is one of the least specialized of 
the family, and is specially adapted to flies. It is hardly to 
be expected that such a form would give rise to a large group 
of species nearly all of which are specially adapted to bees. 
Nor does it seem probable that small crowded erect flowers 
with exserted stamens would give rise to a multitude of 
flowers all of which had included stamens touching the insect’s 
back. That Mentha is of a form approaching a simple regu- 
lar flower is plain, but it seems to me to be a very different 
form from that of the original common ancester of the Labi- 
ates. It is rather a modification of a more irregular form, 
which I think will be more evident when we undertake to 
consider the forms in their divergence from the more charac- 
teristic form of Labiate flower. 
It is difficult to find a flower which in its form and func- 
tion realizes the type. Of those mentioned in this paper, 
perhaps Scutellaria parvula approaches the type as nearly as 
any, though it is probably too small. In this we have about 
two flowers open at a time on the leafy axis. Each flower 
is wholly independent of neighboring flowers. The lower lip is 
the main attractive part and invariably serves as a landing- 
_ place for small visitors. The anthers and stigma are con- 
cealed under the upper lip and always come in contact with 
the back of the insect. The nectar is concealed ina slender 
tube. The color is blue, with pathfinders, and the flower 
is adapted to bees. 
The first condition which seems to be a departure from the 
