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coloration confined to the under sides of a butterfly. This insect, as 

 most of you will know, is brown on the upper surfaces of the wings, 

 but the under sides are bright green. When danger is imminent it 

 settles on a leaf, erects its wings over its back, and is effectually 

 concealed. 



Many other examples of protective coloration among Butterflies 

 could be given, but I think those I have referred to will suffice. If 

 you recall your experiences many instances will doubtless occur to 

 you where you may remember to have noted a resemblance between 

 the undersides cf a butterfly and the object upon which it rested, 

 but which you may possibly have considered only a coincidence and 

 not as an illustration of protective coloration. 



Among the Bombyces and Notodontidce there are many remarkable 

 imitations of bark, twigs, and withered leaves. For instance, Cossus 

 Jigniperda and Stauropus fagi, resemble the bark of trees on which 

 they rest. Phalera bucephala rests on branches of trees or bushes, 

 and the yellow patch on the hinder portion of its fore wings re- 

 presents the fractured base of a recently detached twig. Lasiocampa 

 quercifolia at rest is very like a cluster of dead leaves. 



Several species of Noctuoz and Geometrcz habitually rest on the 

 trunks of trees, e.g., Acronycta megacephala on poplar, Acronycta 

 Hgustri on ash. 7'ephrosia punctulata on birch, Eupithecia abbreviata 

 on oaks, and Eupithecia rectangulata on apple or crab. All these 

 afford good illustrations of insects possessing colour and ornament- 

 ation in harmony with their resting-places. Most collectors of 

 Lepidoptera will have observed these insects in repose, and will not 

 have failed to remark how beautifully they assimilated with the bark 

 of the trees upon which they were noticed. 



Various species of moths are sometimes found on palings, but as 

 a rule their occurrence in such situations is probably due to accident. 



It is well known that when the wind has been blowing with some 

 degree of force from a favourable quarter during the night, examina- 

 tion of fences in certain localities early the following morning, often 

 results in the finding of numerous specimens of Lepidoptera ensconed 

 thereon. At other times, long stretches of fencing will not yield a 

 single moth. It may therefore be concluded that in the majority of 

 cases moths rest on pales and other kinds of fencing rather from 

 the force of circumstances than from the exercise of their own free 

 will. Some few species of Lepidoptera do habitually, but not ex- 

 clusively, repose on old fences, especially when such fences are 

 plentifully covered with lichen. The lichen, for instance, would 



