The senses of insects Author:Auguste Forel Purchase of this book includes free trial access to www.million-books.com where you can read more than a million books for free. This is an OCR edition with typos. Excerpt from book: CHAFrER III VISION (continued) Colour Vision; Ultra-Violet Vision; Vision of Form NO modification of first-rate importance needs to be made in what I wrot... more »e in 1878, which is recapitulated in chapter ii. The chief discovery which we have to note since then has been made by Lubbock.1 This author found that ants perceive the ultra-violet rays of the spectrum, which we are unable, or almost unable, to perceive. He took, in a very ingenious manner, advantage of and utilised the fear that ants have of leaving their pupae in the light. Some ants, in an artificial nest, had put their pupae, thanks to Lubbock's precautions, in a division situated under a piece of glass which could be uncovered at pleasure. When the glass was uncovered, the ants carried the pupae away ; when it was covered up they brought them back, especially when a little heat was concentrated thereon. Lubbock then placed his ants in a darkened chamber and passed successively over the uncovered glass the different colours of the solar spectrum. The ants allowed the pupae to remain under the red rays, but carried them off when any other rays rested on them, seeming specially disturbed by the violet and even more by the ultra-violet rays, which are invisible (or nearly so) to man. When the ultra-violet part of the spectrum was directed from the darkness on to the glass the ants quickly carried off the cocoons. Solutions which, transparent to our eyes, absorbed the ultra-violet rays, had on the ants the effect of shade. This fact is of very great general interest, for if it does not precisely demonstrate a sixth sense, it at least proves that ants perceive a variety of light which wecannot perceive as such, whilst they do not appear to perceive red as we perceive it.1 1 Lubbock, Ants, Bus, and Wasps, London, 1882, ...« less