The following illustration from Mr. Darwin's account of the first orchid selected, will suffice. Just _above_ the entrance to the honey store, lies a pouch connected with the pollen store. As the head of the bee is pressed down towards the honey, this pouch is burst open, and from it issues a little sticky gland or disc, or it may be two of these discs. These adhere at once to the head of the bee, and being connected by a slight band with packets of pollen grains so soon as the animal retires the pollen is drawn with it, standing out like a seed vessel on the head. The strangest part of the contrivance appears in what thereafter follows. "The viscid matter has the peculiar chemical quality, of setting like cement, hard and dry in a few minutes." Suppose both the little viscid balls have been withdrawn, the bands bearing the pollen will appear "projecting up like horns." "How then can the flower be fertilized? This is effected by a beautiful contrivance; though the viscid surface remains immovably affixed, the apparently insignificant and minute disc of membrane to which the caudicle adheres is endowed with a remarkable power of contraction, which causes the pollinium to sweep through an angle of about ninety degrees, always in one direction towards the apex of the proboscis, in the course of thirty seconds on an average."[BW] That is, the two erections bearing packets of pollen which formerly stood up almost perpendicular, like horns, begin to lower until they reach the horizontal; in this way when the bee enters a flower the packets of pollen inevitably touch the seed stores, communicating what is required for their fertilization. Nor have we even yet the whole of the contrivances adapted for this end. "Here comes into play another pretty adaptation." The seed vessel to be fertilized is very sticky, "but not so viscid as when touched by a pollinium to pull the whole off an insect's head." But it is sufficiently adhesive "to break the elastic threads by which the packets of pollen grains are tied together." In this way, it tears off so much from the store adhering to the head of the bee, and still leaves there what may supply the requirements of many flowers besides. The description thus given will suffice to indicate how close is the relation of the lower orders of animal life with vegetable life, and will illustrate how the lower organism may be dependent for existence on the higher, an illustration in some respect the converse of the facts illustrating origin of species by development.