122 MICROSCOPICAL OBJECTS FOUND 



bottom of the sea only furnished an abundance 

 of Foraminifera. These facts indicate im- 

 portant differences in the effect of external 

 influences, and at least show that the evidence 

 afforded by the Foraminifera, must not be 

 allowed to outweigh that furnished by the 

 higher plants and animals, which are so much 

 more sensitive to changes of latitude, climate, 

 and depths of ocean. This is all consistent with 

 what we know of the low sensibility of even 

 those higher forms of Infusorial animals, such as the 

 Rotifera, which. Dr. Carpenter tells us, may be 

 frozen up in ice and thawed again for a succession 

 of times without life being destroyed. The Fora- 

 minifera, it must be remembered, have a much 

 less complicated organization, and hold a lower 

 position in the scale of animal life than the 

 Rotifera, and, consequently, might be expected to 

 be still less under the influence of external agents. 



More recently M. Ehrenberg appears to have 

 altered his opinion on some of these points. In 

 a recent work* he remarks, " As a considerable 

 number of the species of animals belonging to the 



* Verbreitung und. Einfluss des Mikroskopischen Lebens 

 in Slid und Nord America. 



