Bees, too, are sometimes so well imitated that they are hardly to be distinguished from their mimics, not in flight only, but also when visiting flowers. The best and commonest mimic of our honey-bee is a perfectly harmless fly of the same size and colour, the drone-fly (_Eristalis tenax_). The two are often to be seen together on the same flowering shrub, as, for instance, in autumn, on the Japanese buckwheat of our gardens (_Polygonum sieboldii_), both busily seeking for honey. I once noticed a boy catching the flies with a net in order to imprison them, but a bee stung him severely in the finger. He immediately abandoned the chase, and gave up the flies, perceiving the dangers of confusion. So the animal enemies of _Eristalis_ will often prefer to leave it in peace rather than run the risk of being stung. PLATE III FIG. 24. ELYMNIAS UNDULARIS, MALE OF THE SPECIES OF WHICH THE MIMETIC FEMALE IS DEPICTED IN FIG. 23. 25. EUPLŒA BINOTATA, IMMUNE INDIAN SPECIES, MIMICKED BY 26. ELYMNIAS LEUCOCYMA, MALE, OF WHICH 27. EUPLŒA MIDAMUS. 28. THE FEMALE MIMICS FAIRLY CLOSELY 29. DANAIS VULGARIS, IMMUNE INDIAN DANAID. 30. ELYMNIAS LAIS, MIMETIC OF THE FOREGOING SPECIES, BUT ONLY ON THE UPPER SURFACE. THE LOWER SURFACE RETAINS THE ORIGINAL PROTECTIVE COLOURING REPRESENTING A DECAYING LEAF. 31. TENARIS BIOCULATUS, FROM THE PAPUA REGION. 32. ELYMNIAS AGONDAS, MIMICS THE FOREGOING SPECIES FROM THE SAME LOCALITY. _To face Plate III_ [Illustration: PLATE III. LONDON: EDWARD ARNOLD.] There is still another relation between two species which can be induced by mimicry--namely, parasitism, when, for instance, the so-called cuckoo-bees and parasitic humble-bees deceptively resemble in colour, arrangement of hair, and form of body, the species into whose nests they smuggle their eggs, to have them brought up at the expense of the bee or humble-bee in question. In the same way, among the numerous parasites of ant nests, there are some which copy the ants themselves, and so secure themselves from molestation, although they devour the ants' eggs and pupæ. Thus, among the hosts of South American driver-ants (_Eciton prædator_) there lives a predaceous beetle of the family Staphylinæ, which has received the name _Mimeciton_ because it resembles the ant in form and in the nature of the external surface, though not in colour, which is to be explained by the fact that this ant has no compound eyes, and is therefore almost blind, or at any rate cannot see colours.