No. 423.] NORTHERN POLYPETALOUS FLOWERS. 235 
importance in attracting insects, compared with its sunny, 
sheltered location and easily accessible supply of honey. 
Few plant families have attained a form of inflorescence so 
well adapted to insure cross-fertilization as the Umbelliferz. 
To this family belong the caraway and carrot, the wild parsnip, 
the water hemlock, and parsley, — plants growing luxuriantly by 
the roadside, along the river, and in the meadow. There are 
about 1600 species, mostly confined to the temperate zone. 
The flowers differ very little in structure, and the species can 
be identified only by the mature fruit. The small flowers gain 
conspicuousness by aggregation, and by standing in the same 
horizontal plane afford a convenient landing place for insects, 
and admit of rapid fertilization. The honey is secreted in a thin 
layer by the fleshy disk surrounding the style. The number 
and variety of the visitors surpass those of all other families. 
In Germany there have been collected on the caraway 55, on 
the wild carrot 61, and on the wild parsnip 118 insects. Prob- 
ably the number of visitors to many species exceeds 200 ; while 
there is thus ample provision for intercrossing, self-fertilization 
is in most species prevented by the anthers and stigmas matur- 
ing at different times. Admirable simplicity and perfection are 
here combined. 
There are 58 white, 16 yellow, 1 purple, and 3 blue flowers. 
As in the Cruciferz, which have also very uniform flowers, white 
and yellow predominate, red and purple are more rare. The 
16 yellow flowers belong to 11 genera, only three of which con- 
tain more than one species. In his Fertilization of Flowers 
Müller enumerates 7 Diptera and 7 Hymenoptera collected 
on the dull-yellow flowers of Pastinaca sativa; 4 Diptera 
and 4 Hymenoptera on Bupleurum falcatum ; 15 Diptera and 
31 Hymenoptera on Anethum graveolens ; and remarks, “So the 
dull-yellow flowers of this plant, P. sativa, like those of Bupleu- 
rum and Anethum, are visited only by Diptera and Hymenop- 
tera, not by beetles.” On page 574 he adds: “ All dull-yellow, 
dirty-yellow, brownish-yellow, yellowish-white flowers, Bupleu- 
rum anethum, Pastinaca, Rhus cotinus, Galium mollugo, Ruta, 
Neottia, Euonymus, Euphorbia, Adoxa, Alchemilla, are entirely 
or almost mary. avoided by beetles. The only apparent 
