° 1918 J Recent Literature. 373 



from cocoons of Emperor moths (Samia cecropia) . The probability is that 

 these objects are placed in the cocoons by birds addicted to hoarding. No 

 very definite observations on the agents have been made, the most satis- 

 factory being those of Dr. Alex. Wetmore of the Biological Survey who has 

 seen Bluejays stuff grains of corn and small acorns into large cocoons. — 

 W. L. M. 



Bird Enemies of Tree Hoppers (Membracidae). — In an admirable 

 paper on the ' Biology of the Membracidae of the Cayuga Lake Basin,' 1 Dr. 

 W. D. Funkhouser discusses the relations of birds to these insects. He 

 presents records of seven definitely named species of birds feeding on tree 

 hoppers, in addition to warblers (various species) and thrushes (various 

 species), which we wish were particularized. 



The greatest interest in connection with the records relates to the al- 

 leged protective adaptations of Membracids. Dr. Funkhouser states: 



"Very few of the local species are molested by birds. A few species 

 of birds have been observed feeding on the nymphs but usually neglecting 

 the adults, the latter being probably sufficiently protected from bird 

 enemies by the hard pronotum and sharp processes. Various species of 

 adult membracids have been thrown to birds in captivity; in general these 

 have been refused but in a few cases they have been picked up only to be 

 dropped again. Evidently the strong pronotal processes, which are often 

 sharp and hard enough to pierce the skin if the insect is seized suddenly, 

 are unpalatable and irritating." (pp. 416-7). 



In these remarks Dr. Funkhouser evidently has fallen, probably uncon- 

 ciously, into the habit of speculation, which selectionist doctrine has 

 almost ingrained in biologists and especially in biological teaching. That 

 Dr. Funkhouser does not accept these views at face value is shown by the 

 following further quotation from his paper: "Poulton * * * has called 

 attention to the fact that it is hard to deny the theory of protective re- 

 semblance when the same object is accomplished by both the nymph and 

 the adult but in different ways. In the case of the local forms mentioned 

 above, the nymph imitates the uncurling leaf or the irregular bark by spines 

 on both thorax and abdomen — chiefly the latter — while the adult 

 imitates an entirely different part of the plant by the development of an 

 entirely different part of the body. On the other hand, some of the com- 

 monest of the local species of Membracidse in no respect seem to resemble 

 any part of the host on which they live, although their shapes are decidedly 

 peculiar. The high dorsal crest of the Telamonas, for example, can only 

 by a stretch of the imagination be made to resemble any peculiarity of the 

 oak twig on which the insects rest, and in fact they are very conspicuous 

 on their host. Likewise the Ceresas, perhaps the most widely distributed 

 genus in the basin, are plainly seen when in their natural surroundings, 

 and the two prominent suprahumeral horns do not in the least resemble 

 plant structures with which the insects are associated. The answer of 



i Mem. 11, Cornell Univ. Agr. Exp. Sta. June, 1917. 



