1912.] NATURAL SCIENCES OF PHILADELPHIA. 325 



The experiments were performed in Ceylon with Gracula sp., 

 and domestic fowls. "So far as these experiments teach any- 

 thing, it would appear that these mainas would eat with relish 

 Nissanga patina, Yphthima ceylonica, Atella phalanta, Ergolis 

 sp., and Lampides sp. On the other hand, Papilio aristolochice 

 and Crastia asela were distinctly distasteful. The evidence 

 as to the other species experimented with fails to convince me 

 one way or the other" (p. 631). In several of the experiments 

 the birds apparently were not hungry enough to care for any- 

 thing. 



Experiments in Africa. 



In their extensive and interesting paper on the " Bionomics of 

 South African Insects," 76 Marshall and Poulton record the results 

 of experiments with kestrels (Cerchneis rupicoloides and C. naumanni) 

 and a ground horn-bill (Bucorax caffer). 



The experiments with the kestrels (pp. 340-345) are characterized 

 by the average small number of trials of the various insects used. 

 The writer desires to draw attention to only one point in the dis- 

 cussion of these experiments. On p. 346, Poulton says with regard 

 to some supposedly distasteful beetles which the birds had eaten: 

 "It is probable that most of the defensive fluid had been already 

 discharged in the case of the Carabidse of the genera Piezia, Poly- 

 hirma, and Graphipterus, of which the acid secretion was seen to be 

 a very positive protection when there was opportunity for its opera- 

 tion on a normal scale." The "normal scale" referred to was the 

 offering of the beetles tail first! Marshall found these carabids in 

 the stomachs of certain wild birds, and in discussing this Poulton 

 says the fact is not remarkable, as "the defensive secretions may be 

 discharged and lost as the result of the attacks of an experienced 

 enemy" (p. 353). This better illustrates action on a "normal 

 scale." 



The ground horn-bill experimented upon by Marshall (pp. 347- 

 348) ate all butterflies offered it, including several of the reputed 

 "protected" forms, with the exception of two specimens of Limnas 

 (Danais) chrysippus. Poulton, therefore, remarks: "It has already 

 been pointed out that the acceptance of insects by insectivorous 

 animals in captivity is no proof of their normal likes or dislikes in a 



wild state Hence the fact the Acrseas were devoured is.no 



evidence that thej- are normally eaten except in a time of unusual 

 hunger" (p. 348). Marshall, 77 however, says: "The bird was 



76 Trms. Ent. Soc. Loud., 1902, pp. 287-504. 

 ~ Trans. Ent. Soc. Lond., 1908, p. 139. 



