FAMILY OF COMMON SQUIRRELS (Sciurus vulgaris} 



As in Birds, parental affection has much to do with the success 

 of Mammals in the struggle for existence. The chances of indi- 

 vidual survival in the latter class are also furthered by development 

 being internal (except in the egg-laying Duck-bills and Spiny Ant- 

 eaters), and by the presence of milk-glands for the benefit of the 

 young. In the large and widely-distributed order of Gnawing 

 Mammals (Rodentid), fecundity plays a very important part in 

 preventing extinction. The young may be born in a well-developed 

 state, but the contrary is the case when they are brought up in 

 some sort of dwelling or nest, as in the Common Squirrel. The 

 " drey " of this animal is a snug habitation, built in a hole or tree- 

 fork. Dry twigs are woven together into a rounded structure, with 

 a hole on one side. Leaves, moss, lichen, and similar material are 

 used for lining purposes. From three to four blind and naked 

 young are born within this cosy dwelling, usually in June, and 

 remain with their parents till the following spring, when they in 

 their turn undertake family duties. 



