ioo HIDDEN BEAUTIES OF NATURE 



forms, with such geometrical regularity and such 

 elegant architecture.' The material of the skeleton 

 or shell is derived from the exceedingly small pro- 

 portion of silex contained in ocean water. 



After death, the Radiolarian shells or skeletons 

 sink to the bottom of the ocean, where they ac- 

 cumulate as an abundant component of the 'mud,' 

 disrespectfully so called. The greatest recently- 

 formed layer of modern Radiolarian shells occurs 

 on the floor of the central Pacific Ocean. But we 

 have, as yet, no certain means of ascertaining its 

 depth. Neither do we know anything as to the 

 date of the commencement of its deposition. 



Professor Haeckel looks upon the Radiolarian as 

 a creature organized more highly than the Foramini- 

 fera, which take up and secrete chalky matter. He 

 says that each creature consists of a central capsule 

 of firm membrane enclosing masses of minute cells. 

 The exterior of this capsule contains numerous 

 yellow cells, which enclose starch grains, and from 

 it emanate in all directions countless feelers or 

 pseudopodal rays. By means of these rays the 

 creature draws in its food. 



Closely allied to these Radiolarians, if at all separ- 

 able from them, are most extraordinary creatures 

 called Challengeria and Tuscarora, after the well- 

 known ships formerly employed for scientific pur- 

 poses of a peaceful character. 



They form beautiful groups of minute life. They 

 are smaller than the average Radiolarian. ' They 



