CHAP, ix.]' THE DEEP-SEA FAUNA. 409 



they play in the economy of nature, would seem to 

 entitle them to a systematic position of more than 

 ordinal value. The German naturalists of the new 

 school, in their enthusiastic adoption of the Dar- 

 winian theory of evolution, naturally welcome in 

 these c moners ' the essential attribute of the ' Ur- 

 schleim,' an infinite capacity for improvement in 

 every conceivable direction ; and to more prosaic 

 physiologists they are of the deepest interest, as 

 presenting the essential phenomena of life, nutri- 

 tion and irritability, existing apparently simply as 

 the properties of a homogeneous chemical compound, 

 and independent of organization. 



The monera pass into the rhizopoda, which give 

 a slight indication of advance, in the definite form 

 of the graceful calcareous shell-like structures which 

 most of them secrete, and the two groups may be 

 taken together. 



The dredging at 2,435 fathoms at the mouth of 

 the Bay of Biscay gave a very fair idea of the con- 

 dition of the bottom of the sea over an enormous 

 area, as we know from many observations which 

 have now been made, with the various sounding 

 instruments contrived to bring up a sample of the 

 bottom. On that occasion the dredge brought up 

 about 1^ cwt. of calcareous mud. There could be 

 little doubt, from the appearance of the contents of 

 the dredge, that the heavy dredge-frame had gone 

 down w r ith a plunge, and partly buried itself in 

 the soft, yielding bottom. The throat of the dredge 

 thus became partly choked, and the free entrance 

 of the organisms on the sea-floor had been thus 

 prevented. The matter contained in the dredge con- 



