How Animals Work. 



of sending out delicate threads or strands, mere elon- 

 gations of the body mass, for the capture of food par- 

 ticles from the surrounding sea water in which it lives, 

 and from which it extracts the carbonate of lime it 

 uses as building material. Indeed, this little jelly-speck, 

 denuded of its elaborate house, is almost exactly like 

 the Amoeba, the most primitive form of animal life ; 

 for, like that microscopic animal, it has no definite 

 organs save the nucleus which is the vital part of all 

 living cells, and can take in food particles at any part 

 of its body, stream rather than creep along, and ulti- 

 mately divide into two identical jelly-specks. But in 

 place of the blunt, finger-like elongations which the 

 Amoeba pushes out as it moves along, our little builder 

 puts forth delicate threads. I am sorry to say this 

 interesting little creature has no popular name, it and 

 its kin being known as the Foraminifera a term first 

 used by D'Orbigny to express the fact that the chambers 

 of their microscopic mansions communicate by minute 

 pores, and not by a tubular passage or siphon as in 

 the chambers of the home of the Nautilus, to which 

 animal he thought them to be related. 



The exquisite shells of the Foraminifera are, for the 

 most part, many-chambered, and often so strongly re- 

 semble those of the Nautilus and the Spirula that in days 

 gone by the old naturalists, to whom their true struc- 

 ture was unknown, thought them to be related closely 

 to the Nautilus and Cuttle-fish. Thanks to the high 

 perfection of the modern microscope, their true nature 

 has been revealed, showing not only the difference in 

 the character of their bodies by which the shells are 

 formed, but also the very different position of the body 



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