NO. 7 PROTECTIVE ADAPTATIONS McATEE ']'] 



correspond very closely to the relative abundance in individuals of 

 these genera. Of the ant-suggesting genera, we have for Eudcrccs 

 five records and for Cyrtophonts one ; and for the ichneumonid- 

 mimic NeolorcJius three identifications. 



The figures for the distinctly warningly colored genera arc 

 Acmacops seven, Dcsmncerus two, Gauroics two, Tctvaopes nine, and 

 Obcrca five. Such a catalogue shows that all the forms, whatever their 

 alleged " protection " are eaten more or less, and there is no other 

 explanation of the comparative extents to which they are taken so 

 reasonable and satisfying as that it prol)ably depends almost entirely 

 on their relative abundance and availability to birds. 



The Chrysomelidae or leaf beetles are classed by Professor Poulton 

 as undoubtedly specially protected, and Donisthorpe writing of them 

 under another name says : " The Phytophaga are considered to be all 

 more or less distasteful, and no doubt justly so. ■Many species have 

 been proved to be so, and the group is mimicked by various orders of 

 beetles throughout the world." (Trans. Ent. Soc. London, 1901, 

 p. 367.) Selectionists should have been somewhat restrained in their 

 theorizing by the very name Phytophaga, for the leaf beetles and their 

 allies being groups that subsist directly upon vegetation, must ac- 

 cording to inevitable law in the organic world form the base of a 

 column of predacious life more or less exclusively dependent upon 

 them. Like the grazing mammals, all plant-feeding insects, no doubt, 

 have their lions, wolves, and eagles, their hyaenas, jackals, and 

 vultures. 



No reason appears from the records of bird food here discussed to 

 warrant doubt that the leaf beetles do in fact contribute their full 

 quota toward the subsistence of predatory animals. The total number 

 of identifications of Chrysomelidae is 5,666, and these are shared by 

 well over 200 species of birds, so it is certain that practically all of our 

 birds feed more or less upon these beetles. More than 230 species of 

 Chrysomelidae are represented in tlie determinations, this in turn 

 indicating that all tribes of the family are preyed upon. The Cassidini, 

 on account of their bright colors and specialized larvae, receive fre- 

 quent mention as a specially protected group but our scant representa- 

 tion of this tribe seems to bear its share of bird prcdation ; Cassida 

 3 records, PJiysonota 2, Coptocycla 48, and Chelymorpha 48. Again 

 correspondence of the number of identifications with observed fre- 

 quency of the insects is quite -evident. 



Resemblance to caterpillar droppings always is spoken of by selec- 

 tionists as a prime defense, and one tribe of oiu" leaf beetles, the 

 Chlamydini, exhibits this to a high degree. When feigning death, as 



