Darwin believed that, “bearing also in mind the larger number of species in many parts of the world which from this same cause are seldom impregnated, we are led to believe that the self-fertilized plants formerly depended on the visits of insects for their fertilization, and that, from such visits failing, they did not yield a sufficiency of seed and were verging towards extinction. Under these circumstances, it is probable that they were gradually modified, so as to become more or less completely self-fertile; for it would manifestly be more advantageous to a plant to produce self-fertilized seeds rather than none at all or extremely few seeds.”[17] Darwin questions: “Whether any species which is now never cross-fertilized will be able to resist the evil effects of long-continued self-fertilization, so as to survive for as long an average period as the other species of the same genera which are habitually cross-fertilized, cannot of course be told.... It is indeed possible that these self-fertile species may revert in the course of time to what was undoubtedly their pristine condition, and in this case their various adaptations for cross-fertilization would be again brought into action.”[18] Indeed, the more this great scientist studied these strange flowers, the more he became impressed, and “with ever-increasing force, that the contrivances and beautiful adaptations slowly acquired through each part occasionally varying in a slight degree but in many ways, with the preservation of those variations which were beneficial to the organism under complex and ever-varying conditions of life, transcend in an incomparable manner the contrivances and adaptations which the most fertile imagination of man could invent.”[19] [Illustration: =The Tall White Northern Orchis= (_Habenaria dilatata_), =Near Arethusa’s Spring, Bogs of Etchowog, Pownal, Vermont.=] The extinction of species of orchids is due to causes inharmonious with Nature, therefore, more than to the failure of the insects in fertilization and cross-fertilization. Man and his bush-whack and bog-hoe are doing more toward the extinction of our rarer species of all plant-life in their continental range than any other natural element, in the swampy, mountainous districts of the East, as well as in the open swells on the prairies of the West. The late Grant Allen expressed regret that the native Yellow Lady’s Slipper of England, _Cypripedium calceolus_, “lingers in but two places,” one of those stations being on “a single estate in Durham, where it is as carefully preserved by its owner as if it were pheasants or fallow-deer.” The wind, rains, and flowing streams, the birds, as well as migration and immigration of the nations over the world, are ever unconscious bearers of the seeds of our rare flowers and common dooryard weeds; yet for the rarer species Nature is indebted to the insects for the important process of cross-fertilization.