stance that only the male, which does not shine, has wings to enable it to seek out the female; the wingless female, on the other hand, since it only comes out in the evening, possesses the phosphorescent light, so that the male may be able to find it. Yet in the case of the Lampyris Italica both sexes shine, which is an instance of the natural luxury of the South. But a striking, because quite special, example of the kind of design we are speaking of is afforded by the discovery made by Geoffroy St. Hilaire, in his last years, of the more exact nature of the sucking apparatus of the cetacea. Since all sucking requires the action of respiration, it can only take place in the respirable medium itself, and not under water, where, however, the sucking young of the whale hangs on to the teats of the mother; now to meet this the whole mammary apparatus of the cetacea is so modified that it has become an injecting organ, and placed in the mouth of the young injects the milk into it without it requiring to suck. When, on the contrary, the individual that affords essential help to another belongs to an entirely different species, and even to another kingdom of nature, we will doubt this external design just as in unorganised nature; unless it is evident that the maintenance of the species depends upon it. But this is the case with many plants whose fructification only takes place by means of insects, which either bear the pollen to the stigma or bend the stamina to the pistil. The common barberry, many kinds of iris, and Aristolochia Clematitis cannot fructify themselves at all without the help of insects (Chr. Cour. Sprengel, Entdecktes Geheimniss, &c., 1793; Wildenow, Grundriss der Kräuterkunde, 353). Very many diœcia, monœcia, and polygamia are in the same position. The reciprocal support which the plant and the insect worlds receive from each other will be found admirably described in Burdach's large Physiology, vol. i. § 263. He very beautifully adds: "This is no mechanical assistance, no make-shift, as if nature had made the plants yester-
