560 Recently published Ornithological Works. 



Newton and others have made suggestions on this subject. But 

 the question arises, has the author ever read Prof. Newton^s 

 article and other recent English pubhcations on the Cuckoo 

 question ? It would certainly seem as if he had never heard of 

 Hudson's most important observations on the parasitic Icte- 

 rid« of Argentina {see P. Z. S. 1874, p. 153, and Arg. Oru. i. 

 p. 72) ; at all events he does not refer to them, and on this part 

 of his subject the information given is by no means up to date.^ 

 The final result arrived at by the author, as given in the 

 penultimate paragraph of this memoir, is, as regards para- 

 sitism, that the Cuckoos do not sit themselves because their 

 eggs are so slowly developed that one general sitting would 

 not do for them, and that it is, therefore, necessary that they 

 should be incubated separately, which can only be done by 

 foster-mothers. But it seems to us quite as likely that 

 parasitism was the original cause of the slow development of 

 the consecutive eggs. 



Eight coloured plates appended to the memoir contain 

 figures of the eggs of various parasitic Cuculidce and Icteridce 

 and their foster-parents. 



95. Beddard on Animal Coloration. 



[Animal Coloration : an account of tbe principal facts and theories 

 relating to the Colours and Markings of Animals. By Frank E. Beddard, 

 M.A. London : Swan Sonnenschein & Co., 1892.] 



This useful volume contains a complete account of the 

 modern theories of animal coloration — protective, warning, 

 mimicking, and sexual— with illustrations drawn from many 

 groups of the animal kingdom. 



Birds, though sharing with insects the brightest colours 

 and tints found in nature, do not ofi'er so many instances of 

 the more striking phenomena of this kind as Insects. 



Among instances of so-called protective mimicry in 

 birds are mentioned the Cuckoos, in which family the genera 

 Centropus and Carpococcyar show much resemblance to the 

 Gallinaceous Birds, and Cuculus and its allies, more especi- 



* For instance, no mention whatever is made oiMolothrus rufo-axillarit 

 and its excessively curious habits, as observed by Mr. Hudson. 



