Natural History Notes and Extracts 461 



much nearer to fish than true reptiles are, being in their 

 early, or tadpole, stage provided with gills and able to 

 breathe under water. 



True reptiles are land living animals and require to breathe 

 air. They undergo none of the metamorphic changes which 

 are so interesting in the case of frogs and toads. Snakes, 

 lizards, tortoises, &c, are Reptiles, that is, belong to the 

 class Reptilia. 



Cuckoo Notes. 



Some interesting notes on the origin of parasitic habits 

 in cuckoos were contributed to the Emu last year by Mr. C. L. 

 Barrett, of Melbourne. It is stated that one American specie? 

 sometimes lays in the nests of other birds though it usually 

 prefers to build its own nest and hatch its own eggs. Five 

 species of the Indian hawk cuckoos (Hierococcyx) lay in the 

 nests of babbling thrushes, but the sixth makes its own nest. 

 Mr. Barrett cites a theory that the food of the nestling cuckoo 

 has an influence in determining the colour of the eggs it may 

 subsequently lay. He remarks, " If such be the case, it goes 

 far to explain the similarity between the eggs of many species 

 of cuckoos and those of their foster parents." 



The two following paragraphs are quoted from " The Early 

 Life of the Young Cuckoo," by W. Percival Westell : — 



" I have always found the hedge-sparrow to be charged 

 with the rearing of the great sprawling youngster more than 

 any other bird, and I well remember one lucky day in Bed- 

 fordshire, some six or seven years ago, finding half-a-dozen of 

 these nests in one morning, each containing an egg of the 

 cuckoo. Other favourite foster-parents are the robin, meadow 

 pipit, whitethroat, reed warbler and pied wagtail. The egg 

 is laid on the ground and carried to the selected nest in the 

 bird's beak, not in the claws as has been erroneously stated. 

 It is the smallest egg laid by any British bird in comparison 

 to its size, being very little larger than a house sparrow's, or 

 perhaps, almost the size of a skylark's. In its colouring the 

 egg varies a great deal and columns might be devoted to this 



