Some Phenomena in Sponges 
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1 
! 
lieu of more precise knowledge it is useful to regard the pseu- 
dopodia as structures which explore and learn about the envi- 
ronment. On coming in contact two masses of the same spe 1 
cific protoplasm tend to fuse. This tendency is probably use- 
ful ( 2 . e., adaptive) in that the additional safety (from ene- 
mies and ‘'accidents”) accruing from increase in size of the 
mass more than compensates for the reduction in number of 
the individual masses that start to grow (rearing of sponges 
shows that masses of good size frequently withstand condi- 
tions that effectually wipe out the very small masses.) Unlike 
specific substances (protoplasms of quite different species) do 
not tend to fuse. 
To the many biologists who have found ideas and observa- 
tions of deep interest in the papers on protoplasmic activities 
by Professor and Mrs. E. A. Andrews (G. F. Andrews), the 
statement just made will have a familiar sound. Mrs. 
Andrews in her essay on The Living Substance as Such and 
as Organism 9 and her paper on The Spinning Activities of 
Protoplasm 10 makes, it would appear from subsequent confir- 
mations, a definite advance in our knowledge of the intimate 
structure of protoplasm. But it is her generalizations, based 
on singularly acute observations, with respect to the behavior 
of protoplasm, that have especially influenced my own work. 
The particular generalizations referred to ma} r be so formu- 
lated: 
1 Protoplasm tends to produce a viscous, pellicular layer 
with formation of pseudopodial outgrowths over the surface, 
whether external or internal to the mass, which establishes 
contact with the environmental medium. 
2 Pseudopodia from adjacent masses of the same specific 
substance tend to fuse. Thus actual connections which can 
be made and remade, and along which transference of sub- 
stance takes place, are established between the masses. 
That these phenomena are observable in widely separated 
groups of metazoa has been also shown by Professor Andrews 
9 Suppl. to Journ. Morphology, vol. xii, no. 2,^1897. 
lOJourn. Morphology, 1897. 
