226 OUR SUMMER MIGRANTS. 



in " Nature" and elicited various critical re- 

 marks from Mr. H. E. Dresser, Mr. Layard, and 

 other ornithologists which deserve perusal. 1 



To enter fully upon the details of this interest- 

 ing subject would require more space than can 

 here be accorded ; one can only glance therefore 

 at the general opinions which have been ex- 

 pressed in connection with it. 



If the theory of Dr. Baldamus be correct, is 

 it possible to give a reasonable and satisfactory 

 explanation of it ? This question has been 

 answered by Professor Newton in the article to 

 which we have just referred. He says : 

 " Without attributing any wonderful sagacity to 

 the Cuckoo, it does seem likely that the bird 

 which once successfully deposited her eggs in a 

 Reed Wren's or a Titlark's nest, should again 

 seek for another Reed Wren's, or a Titlark's 

 nest (as the case may be) when she had an egg 

 to dispose of, and that she should continue her 

 practice from one season to another. We know 

 that year after year the same migratory bird will 



1 See "Nature," i8th Nov. and 2$rd Dec., 1869, 6th Jan., 

 7th July, and i8th Aug. 1870. 



