CHAP. 1X] THE DEEP-SEA FAUNA. en 
to give a slight viscosity'to the mud of the surface 
layer. If the mud be shaken with weak spirit of 
wine, fine flakes separate like coagulated mucus ; 
and if a little of the mud im which this viscid con- 
dition is most marked be placed in a drop of sea- 
water under the microscope, we can usually see, 
after a time, an irregular network of matter resem- 
bling white of egg, distinguishable by its maintaining 
its outline and not mixing with the water. This 
network may be seen gradually altering in form, and 
entangled granules and foreign bodies change their 
relative positions. ‘The gelatinous matter is therefore 
capable of a certain amount of movement, and there 
can be no doubt that it manifests the phenomena of 
a very simple form of life. 
To this organism, if a being can be so called which 
shows no trace of differentiation of organs, consist- 
ing apparently of an amorphous sheet of a protein 
compound, irritable to a low degree and capable of 
assimilating food, Professor Huxley has given the 
name of Bathybius haeckelii (Fig. 63). If this have a 
claim to be recognized as a distinct living entity, ex- 
hibiting its mature and final form, it must be referred 
to the simplest division of the shell-less rhizopoda, or 
if we adopt the class proposed by Professor Haeckel, 
to the monera, The circumstance which gives its 
special interest to Bathybius is its enormous extent : 
whether it be continuous in one vast sheet, or broken 
up into circumscribed individual particles, it appears 
to extend over a large part of the bed of the ocean ; 
and as no living thing, however slowly it may live, 
is ever perfectly at rest, but is continually acting and 
reacting with its surroundings, the bottom of the 
