1897] NOTES AND COMMENTS 225 



' orthodox ' theories have been noticed in Natural Science. In de- 

 fence of the old positions we notice a short paper by Mr F. M. 

 Webster of Ohio, in the Keport of the Entomological Society of 

 Ontario for 1896 (pp. 80-86). The author minimises the value of 

 experiments, tending to show that insects with ' warning ' colours 

 are not always distasteful. He points out that the fact that Prof. 

 Plateau enjoyed feeding on the caterpillars of the magpie moth 

 does not prove them palatable to more usual enemies. No insect 

 is so familiar an example of ' warning ' colour as the North 

 American danaid butterfly, Anosia archippus. Mr Webster narrates 

 an instance of a number of these butterflies being eaten by mice in 

 Texas, and tells how he himself observed a colony of brightly- 

 coloured cabbage bugs (Margantia histrionica) devoured by the same 

 rodents. But he believes that mice must be very exceptional 

 enemies to these species, and that the bright colours may be of 

 ' warning ' value to animals that eat insects habitually. 



The same author in another paper (Journal New York Entom. 

 Soc, 1897, pp. 67-77) deals with the mental or instinctive factors 

 in protective resemblance. It is well known that in addition to 

 the form and colour of the insect, a special attitude or a position on 

 some particular background of leaf or twig is essential to the per- 

 fection of the illusion. Mr Webster believes that such habits have 

 not been developed without the action of some conscious will and 

 intelligence on the part of the creatures concerned. He compares 

 the young twig-like caterpillar to the human infant who has 

 inherited none of the accumulated knowledge of his ancestors, 

 though he has inherited an aptitude for learning. 



The Effect of Civilisation on the North American Insect 



Fauna 



Another subject of general interest, lately dealt with by Mr 

 Webster (Fifth Annual Report of the Ohio State Academy of Science), 

 is the effect of civilisation on the insect fauna of North America. 

 In few other parts of the world has so rapid a change been made in 

 the natural aspect of the country by the advent of the pioneer and 

 the farmer, and the transformation of swamps and forests into cul- 

 tivated fields has led to the extinction of many native species of 

 insects. Some species, however, have adapted themselves to the 

 changed conditions, while a considerable introduction of Tropical 

 and European forms has been a direct result of the advance of 

 civilisation. Mr Webster rightly lays stress on the importance of 

 systematic observations on the natural history of new countries, 

 wherever possible, before the balance of nature has been disturbed 

 by the advent of the white man. 



