370 HISTORICAL GEOLOGY. 



Animals. 



The similarity in general appearance of most Tertiary 

 invertebrates to living species is so great that we shall 

 only draw brief attention to a few interesting points. 



Mollusca. We are all doubtless interested in the fam- 

 ily history of the oyster. The family commenced in the 

 Jurassic, increased in the Cretaceous, and culminated in 

 the Tertiary, and then declined. The Ostrea Georgiensis 

 and the Oarolinensis of the Eocene were several times 

 larger than their modern representative. The Ostrea 

 Titan, of the Pacific coast Miocene, was still larger, being 

 thirteen inches long, eight inches wide, and six inches 

 thick. Lest some may regret inconsolably the passing 

 away of these magnificent oysters before the advent of 

 man, I hasten to remind them that what has been lost in 

 size has probably been gained in flavor. 



Insects. Insects are always closely associated with 

 land vegetation, and the kinds of the one are determined 

 by the nature of the other. Now, for the first time, the 

 highest flowering plants are abundant, and now, for the 

 first time also, all orders of insects, even the highest 

 flower-loving kinds, such as butterflies, bees, ants, etc., 

 are abundant (Fig. 333). On account of the .greater 



FIG. 333. Ants and bees of European Miocene. (After Heer.) 



warmth and moisture, both vegetal and insect life were 

 fuller even than now. \Ye select a few examples of find- 

 ings, by means of which we may reproduce in imagina- 



