508 MR. H. W. BATES ON THE LEPIDOPTERA 



see a species of Moth wliicli frequents flowers in the daytime wearing the appearance 

 of a Wasp, we feel compelled to infer that the imitation is intended to protect the other- 

 wise defenceless insect by deceiving insectivorous animals, which persecute the Moth, 

 l)ut avoid the Wasp. May not the Heliconide dress serve the same purpose to the 

 Lepfalis ? Is it not })roha1)le, seeing the excessive ahundance of the one species and the 

 fewaiess of individuals of the other, that the Heliconide is free from the persecution to 

 which the Leptalis is subjected ? 



T think it clear that the mutual resemblance in this and other cases cannot be entirely 

 due to similarity of habits or the coincident adaptation of the two analogues to similar 

 physical conditions. This is a very al)struse part of our subject ; for I think the facts of 

 similar variation in two already nearly allied forms do sometimes show that they have 

 l)een atfected in a similar way by physical conditions. A great number of insects are 

 modified in one direcrtion by a seaside habitat. I found, also, tlie general colours of 

 many widely different s])ecies affected in a uniform way in the interior of the South 

 American continent. But tliis does not produce the specific imitation of one species by 

 another; it only prepares the way for it. 



It is perha})s true that the causes (to lie discussed presently) which produce a close or 

 mimetic analogy cannot operate on forms whicli have not already a general resemblance, 

 owing to similarity of habits, external conditions, or accidental coincidence. Species or 

 groups which have this kiiul of resem1)lance to each otlier have been called by Dr. Col- 

 lingwood recurrent animal forms. The English Bee-Moths owe the narrow and pointed 

 shapes of their wings, which already approximate them to Bees, to their blood-relationship 

 to the Hawk-Moth family. Their Bee-like size, form, and llight doubtless arise from 

 tlieir Bee-like habits. A close specific analogy l)etween any one of these and a Bee, 

 such as exists between the insects discussed in this memoir, could scarcely be due to an 

 accidental resemlilance like that between the Hawk-Motli and a Bee, or to similarity of 

 Imliits. It would mean an adai)tation of the Moth with especial reference to the Bee. 



I believe, therefore, th;it tlie specific mimetic analogies exhil)ited in connexion with 

 the IL'Hc(i)ii(hc are adaptations — -phenomena of precisely tlie same nature as those in 

 which insects and other l)eings are assimilated in superficial appearance to the vegetaiile 

 or inorganic substance on which, or amongst which, they live. The likeness of a Beetle 

 or ;i Lizard to the bark of the tree on which it crawls cannot l)e explained as an identical 

 rcsidt jtroduced l)y a coinmoii cause acting on the tree and the animal. 



Some of tlie imitations I»y insects of inanimate and living objects are very singular, 

 and may be nunitioned in this place. Many caterpillars of Moths, but sometimes the 

 (•as(^s only which are manufactured and inhabited by the caterpillars, have a most 

 deceptive likeness to (h'y (wigs and other objects. Motlis themselves very frequently 

 resenilde tlie l>aik on wliicli they are found, or Iiave wings coloured and veined like 

 tlie fallen le;i\cs on wiiicli they lie motionless. The accidental general resemblance 

 lietween the shaj)e of Moths' wings and leaves lier(> gives nature the ground-work 

 Cor much mimetic analogy. It has been ])ointed out by liossler * that tlu; Buff-til) 

 Motli, when at rest, is intended to represent a broken piece of lichen-covered branch, 

 ■' In iui article on rcNciuhlaiiccs l)(t\vccii insects ami M.'gctabk' substances (Wiener Entoniol. Monatschrift, 1861, 



