MICRO-ORGANISMS 



jelly-like sarcode is observed in living 

 foraminifera to throw out long threads 

 which, however, are soon delicately en- 

 cased by carbonate of lime, and as this 

 shell remains after the animal which made 

 it dies, so it stays as a slender tube of stone, 

 thus explaining both the canals and the 

 holes through which the sarcode threads 

 exude, and from whence the name fora- 

 minefera. It has been demonstrated, how- 

 ever, by Oscar Hertwig and by other com- 

 petent observers that this apparently sim- 

 ple sarcode contains that great official, the 

 Nucleus, with all his high prerogatives, 

 to whose agency must be attributed the re- 

 markable constructive powers of these or- 

 ganisms. Some of their kinds live in fresh 

 water where they, however, have no lime 

 to work with, but their protoplasm is 

 equal to the occasion, for they then make 

 an envelope of Chitin, a substance which is 

 the animal analogue of vegetable cellulose. 

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