CHAPTER XIII 



REPRODUCTION {continued)— CAKE OF THE OFFSPRING 



Brooding and " brood-spots ". Care for the sitting female. The remarkable 

 case of the Horn-bill. The brooding of the Emperor Penguin. Brooding of 

 Egyptian Plover and of Megapodes. Forsaking eggs. Osprey and care of 

 eo-crs. Transportation of eggs by parents. Precautions against floods. 



AT first sight it may seem that the jealous care which 

 birds bestow on their offspring originated with the 

 necessity for brooding the eggs. But this is clearly not 

 the case, since among the invertebrates there are numerous in- 

 stances to be found where a high degree of concern appears to 

 be bestowed upon the eggs and young to ensure their safety, and 

 these instances become more numerous as we pass in our sur- 

 vey to the lower vertebrates. With the birds and mammals, 

 however, this care develops into something higher, entailing 

 personal sacrifice in a high degree, so much so that we should 

 perhaps rather speak of the love for their offspring which these 

 creatures exhibit, though there are some striking exceptions to 

 this rule. 



With the birds the cares of the family begin at an earlier 

 stage than with the mammals, inasmuch as it commences with 

 the brooding of the eggs, while the mammals, being viviparous, 

 are necessarily relieved of this responsibility until after the birth 

 of the young. 



To this necessity for brooding the eggs we may ascribe the 

 relative fewness of the young produced at a time, as compared 

 with the reptiles, since no more eggs can be hatched than can be 

 effectually covered by the sitting parent. 



Among the mammals but little preparation, as a rule, is 

 necessary for the reception of the young. And this is true of 

 many birds : in the majority of cases, however, a more or less 

 elaborate receptacle, or nest, has to be constructed to contain 

 the eggs during the process of hatching (see p. 176). 



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