Ins] AND SYMBOLS. i?3 



reveal an immense quanity in the white chalk that extends 

 from Champagne into England. Finally, in the tertiary forma- 

 tions of numerous localities, and especially in the environs of 

 Paris, the limestone-grit encloses an infinite number ; and it has 

 been calculated that a cupid yard of this stone, excavated from 

 the quarries of Gentilly, contained more than three millions of 

 individuals. Paris, as well as many neighbouring towns and 

 villages, is almost wholly built with these foraminifera. Thus, 

 then, animals hardly perceptible to the unassisted eye change 

 to-day the depth of the waters, and have, at various geological 

 epochs, filled basins of a considerable area. This fact shows us 

 that each animal has its allotted task, and that with time time 

 of which Nature takes no count the animals which appear to 

 us so contemptible on accouut of their smallness might change 

 the aspect of the globe." MY. 



Instinct. 



The operations of instinct are unvarying. The ant and the 

 hen act now as they acted in the days of King Solomon, and 

 are incapable of altering their course of action. " What can 

 we call the principle," asks Addison, " which directs every kind 

 of bird to observe a particular plan in the structure of its nest, 

 and directs all the same species to work after the same model 1 

 It cannot be imitation ; for though you hatch a crow under a 

 hen, and never let it see any of the works of its own kind, the 

 nest it makes shall be the same to the laying of a stick with 

 all the other nests of the same species. It cannot be reason ; for 

 were animals endowed with it to as great a degree as man, then 

 buildings would be as different as ours according to the different 

 conveniences that they would propose to themselves." The 

 young crocodile or alligator, on issuing from the egg, is drawn 

 towards the nearest water. It will even proceed in a direct 

 line for the stream, just as if it had been there many times 

 before, and was perfectly acquainted with the ground. So it is 

 with the young of turtles. The turtle, though a marine animal, 

 goes on shore to lay her eggs and make a nest for them in the 

 sand. Yet no sooner do the little turtles come forth from their 

 shells, and peep over the surface of the sand, than they 



