which, though distasteful, can scarcely be looked upon as protective. The Giraffe possesses this quality, and Mr. Bryden relates that when following one of these animals, his horse, "hitherto the steadiest shooting pony in the world, had early in the run got wind of the strong musky odour which all Giraffes possess, and bored to the left hand, and I had a good deal of trouble to persuade him to keep straight."[1] Mr. Thomson suggests that among animals, at least, these odours may serve as incense, or as stimulant—"but perhaps this usefulness is secondary."[2] An analysis of the evidence, I think, tends to show that the protection thus afforded is partial, and not universal.
Among plants, the Virginian Creeper (Ampelopsis quinquefolia), so frequently planted to cover porches, palings, and walls, develops flowers in midsummer which are very industriously and eagerly visited by bees. The colour does not act as an allurement in this case, for the flowers have green corollas, are hidden away under the foliage, and cannot be seen even by good eyes at a little distance. Yet the bees fly thither from all sides in such a way as to leave no doubt that the flowers of the Ampelopsis can be perceived by them a considerable way off. "Since it is not their appearance, it must be their smell which announces their presence. But to men they appear to be quite scentless."[3] This clearly goes to prove that the sense of smell is very differently developed in men and bees. The very smell of flowers is subject to variation in response to the nature of the soil. This was demonstrated by Dalibard ('Observations sur le Réséda à fleur odorante').[4] He planted mignonette in different soils, using seeds from the same mignonette plant, possessing its well-known fragrance. While the seeds sown in rich garden soil became vigorous, and were well perfumed, the seeds sown in sandy soil produced plants which remained weak and small, and had no perfume. It even seems that the latter did not acquire any odour when transferred to rich garden soil. "Similar facts have since been repeatedly observed and noticed."[5] Another
