TOILERS IN THE SEA. 27 



CHAPTER II. 

 CHALK MAKERS, OR FORAMINIFERA. 



A NIMALS and plants are classified, for scientific 

 -** purposes, in a regular series of groups, accord- 

 ing to their structure and relationship, either in an 

 ascending scale, from the simplest to the most 

 complex, or descending, from the highest or most 

 complete, to the lowest or simplest forms. This 

 classification undergoes modification from time to 

 time, so as to be in harmony with the progress of 

 knowledge, seeking to represent, as nearly as 

 possible, a graduated sequence of animal or vege- 

 table life, upwards or downwards, as the case may 

 be, beginning or ending with the simplest forms. 

 It is of little moment whether the series be an 

 ascending or descending one, so long as the 

 sequence is in accord with ascertained facts. 

 Whether from acquired habits of order, or from 

 prejudice, or from conviction of its many advan- 

 tages, the biologist is always apt to think and 

 write with this classification, almost unconsciously, 

 before him ; and it seems to him the most natural 



