Many will, indeed, ascribe these modifications to conscious deliberation on the part of the animals themselves, and it is impossible to deny that in the case of the more intellectually gifted animals there may be such a thing as a combination of instinctive faculty and conscious reflection. I think, however, the examples already cited are enough to show that often where the normal and the abnormal action springs from the same source, without any complication with conscious deliberation, they are either both instinctive or both deliberative. {99} Or is that which prompts the bee to build hexagonal prisms in the middle of her comb something of an actually distinct character from that which impels her to build pentagonal ones at the sides? Are there two separate kinds of thing, one of which induces birds under certain circumstances to sit upon their eggs, while another leads them under certain other circumstances to refrain from doing so? And does this hold good also with bees when they at one time kill their brethren without mercy and at another grant them their lives? Or with birds when they construct the kind of nest peculiar to their race, and, again, any special provision which they may think fit under certain circumstances to take? If it is once granted that the normal and the abnormal manifestations of instinct—and they are often incapable of being distinguished—spring from a single source, then the objection that the modification is due to conscious knowledge will be found to be a suicidal one later on, so far as it is directed against instinct generally. It may be sufficient here to point out, in anticipation of remarks that will be found in later chapters, that instinct and the power of organic development involve the same essential principle, though operating under different circumstances—the two melting into one another without any definite boundary between them. Here, then, we have conclusive proof that instinct does not depend upon organisation of body or brain, but that, more truly, the organisation is due to the nature and manner of the instinct.