In this sub-class are included the various species of dock, sorrel, nettle, pellitory of the wall, dog’s-mercury, goosefoot, boxwood, hop, mulberry, elm, and catkin, bearing trees such as the oak, hazel, beech, poplar, birch, alder, walnut, and willow, all of which are wind-fertilized. Anemophily is not so common in dicotyledons belonging to the sub-classes; it occurs, however, in the ash, plantain, wormwood, mare’s-tail, and meadow-rue. The number of wind-fertilized monocotyledons far exceeds those adapted to insects, both as regards individuals and species. The extensive order of grasses, the sedges, carices, and rushes, together with the arrow-head, arrowgrass, bur-reed, and bulrush, are all without exception anemophilous. It thus appears that wind-fertilization occurs in many different and widely separated families. Certain negative characters are common to all the wind-fertilized class; no honey is secreted, no perfume emitted, and conspicuous colors are wanting. On flowers of this description it is difficult for a large insect like a bee to obtain a footing; there is no corolla that can serve as a landing-stage for insects to alight. For these reasons anemophilous blossoms are almost entirely neglected by bees and other flower-hunting insects; only in exceptional instances do visitors have recourse to them in search of pollen, but this is so dry and has so little cohesion that it must be difficult indeed for a bee to collect an appreciable quantity of anemophilous pollen. Wind-fertilized flowers thus offer little or no attraction to insects, and are in no way adapted to derive benefit from their visits. On the other hand, there exists in them a number of provisions which admirably adapt them for cross-fertilization through atmospheric agency. The most important of these is abundant pollen; always more than in insect-fertilized blossoms, the quantity produced by some plants of the wind-fertilized class is enormous. The so-called showers of sulphur, occasionally reported in the newspapers, are really great deposits of pollen blown from the male cone of the Scotch fir. It has been known to fall on ships at sea, and has been swept up in bucketsful from their decks. The common ash discharges an immense quantity from its innumerable flowers, so much so that a person shaking a branch when the tree is in bloom is dusted from head to foot with the dry, powdery pollen. That of the elm is also very abundant, and this is more or less characteristic of all plants which depend for cross-fertilization on the wind. At certain seasons, the air may be said to be literally charged with the pollen of anemophilous plants. In the beginning of May, I exposed on the window-sill for forty-eight hours a microscopic slide smeared with syrup, and on examining it afterward detected upward of fifty pollen-grains belonging to various trees, some of which are not to be found within a radius of two miles. The efficiency of the wind as a