RHIZOPODA. 39 
logical deductions which may be drawn from the study of the Horamini- 
fera, Regarded from a physiological point of view, the structural sim- 
plicity of the /oraminifera renders them all the more wonderful. We 
have in them the great equation of life presented to us in perhaps its 
simplest form. They are composed of an organic substance, but cannot 
be said to possess ‘ organisation,” being ‘‘ structureless, and without per- 
manent distinction or separation of parts.” * Nevertheless they perform 
all the physiological functions ; they assimilate food—they live, grow, and 
maintain their integrity in the face of the destructive forces constantly at 
work upon them—they reproduce their like—and they have certain re- 
lations with the external world, being at any rate capable of independent 
locomotion. All these vital actions they effect without possessing a 
single organ permanently set apart for the performance of any one of 
them. Lastly, they have the power of building up an outer envelope or 
shell, which is always beautiful, and is often of the most complex charac- 
ter, and constructed upon a regular mathematical plan. The Foramini- 
Jera, then, of all known animals, offer the most convincing illustration of 
two laws—firstly, that there is something in the action and nature of 
vital forces altogether distinct from anything hitherto observed in the 
physical forces ; and secondly, that life is the cause of organisation, and 
not the vesw/¢ of it: in other words, an animal is organised, or possesses 
structure, because it is alive ; it does not live because it is organised. 
DISTRIBUTION OF FORAMINIFERA IN SPACE.+—The foraminifera 
are exclusively marine or inhabitants of the ocean, and have a world- 
wide distribution, They are mostly very minute, but some of the extinct 
forms attained a size of as much as three inches in circumference (2.25 
the Nummulite, fig. 7). Some forms may be obtained adhering to the 
roots of tangle (Laminaria) at or near low-water mark, but they are 
mostly to be dredged from tolerably deep water. In the deepest parts 
of the ocean which have yet been examined by the dredge—at a depth, 
namely, of nearly three miles—/oraminifera have been obtained in 
abundance. There is also no doubt that in many parts of the deep 
ecean, especially where warm currents exist, there are now forming 
deposits of the shells of Foraminifera, which may well be compared to 
the great masses of white chalk with which the geologist is familiar. 
Foraminifera may generally be obtained for examination from the shak- 
ings of sponges or from the sand of the sea-shore, especialy in warm 
climates. To give some idea of their abundance, it may be stated that 
Plancus found about 6000 specimens in an ounce of sand from the 
Adriatic ; but D’Orbigny calculated that no fewer than between three 
and four millions were present in an ounce of sand from the Caribbean 
Sea. 
* Huxley. 
+ Under the term ‘ Distribution in Space ” come all the facts relating to the Ave- 
sent occurrence of any animal or group of animals upon the globe. Under the term 
“Distribution in Time,” come all the facts relating to the Zas¢ occurrence of any 
animal or group of animals upon the globe. 
