There is another reason, hinted at by Buckland, Miller, and other writers on this subject, which weighs much with my mind. All animals and plants are constructed on a few leading types or patterns, which are again divided into subordinate types, just as in architecture we have certain leading styles, and these again may admit of several orders, and these of farther modifications. Types are farther modified to suit a great variety of minor adaptations. Now we know that the earth is, at any one time, inadequate to display all the modifications of all the types. Hence our existing system of organic nature, though probably more complete than any that preceded it, is still only fragmentary. It is like what architecture would be, if all memorials of all buildings more than a century old were swept away. But, from the beginning to the end of the creative work, there has been, or will be, room for the whole plan. Hence fossils are little by little completing our system of nature; and, if all were known, would perhaps wholly do so. The great plan must be progressive, and all its parts must be perishable, except its last culminating-point and archetype, man. Tennyson expresses this truth in the following lines: "The wish that of the living whole No life may fail beyond the grave; Derives it not from what we have The likest God within the soul? Are God and Nature then at strife, That Nature lends such evil dreams? So careful of the type she seems, So careless of the single life. 'So careful of the type?' but no. From scarped cliff and quarried stone She cries, 'a thousand types are gone; I care for nothing, all shall go. 'Thou makest thine appeal to me: I bring to life, I bring to death: The spirit does but mean the breath: I know no more.' And he, shall he, Man, her last work, who seem'd so fair, Such splendid purpose in his eyes, Who roll'd the psalm to wintry skies, Who built him fanes of fruitless prayer, Who trusted God was love indeed, And love Creation's final law-- Tho' Nature, red in tooth and claw, With ravine, shriek'd against his creed-- Who loved, who suffer'd countless ills, Who battled for the True, the Just, Be blown about the desert dust, Or seal'd within the iron hills? No more? A monster, then, a dream, A discord. Dragons of the prime, That tare each other in their slime, Were mellow music match'd with him. O life as futile, then, as frail! O for thy voice to soothe and bless! What hope of answer, or redress? Behind the veil, behind the veil."