INTRODUCTION 



TO 



THE STUDY OF BIRDS' EGGS. 



The arrangement of the specimens in this case is designed to 

 encourage the observing rather than the mere collecting of birds' 

 eggs, by illustrating some of the many interesting f^icts that may 

 be learnt by the intelligent study of their characteristics. 



It is necessary that the student should be acquainted with the 

 appearance, at least, of the birds mentioned. With very few 

 exceptions these birds may be seen in the general collection. 

 The eggs are discussed under the following heads : — 

 Varied Colouring of Eggs. 

 Protective Colouring of Eggs. 

 Clutches. 



Size of Eggs in comparison with that of the Birds. 

 Forms of Eggs. 

 Grain of the Eggshell. 



VARIED COLOURING OF EGGS. 



Almost every shade of colour is represented in a large collection 

 of birds' eggs. The pigment occurs only on the surface of the egg, 

 and is deposited but a short time before it is laid. 



White was probably the primitive colour of birds' eggs, as it is 

 the colour of those of all reptiles. 



The markings are usually most abundant at the larger end of 

 the egg ; but some eggs, such as those of the Sparrow {Passer 

 domesticus) and the Sparrow hawk {Accipiter nisus) are variable in 

 this respect. 



Young birds, especially of the Hawk family (Falcomdce)^ seldom 

 lay eggs so richly coloured as those laid in their prime, but as old 

 age advances the eggs again become less richly marked. In the 

 three clutches exhibited the eggs of the first clutch are seen to be 

 almost unmarked, those of the next more richly marked, and the 

 last still more so. 



