1910] LIPMAN—SOLUTIONS FOR BACTERIA 215 
and it is impossible to make determinations of all of them, but in the 
foregoing series of experiments enough combinations have been 
tried and sufficient evidence has been adduced to make it quite clear 
that, for at least one class of bacteria, sea water is a physiologically 
balanced solution just as truly as it is for animals and the higher 
plants. Therefore, although some of the results exhibit some puzzling 
aspects, the prime object of these investigations—to discover whether 
sea water or other balanced solutions are superior to unbalanced 
solutions—is attained. The inexplicable facts which are bound to 
arise in such investigations must be accounted for by future research, 
but the universality of Lorn’s conception of “ physiologically balanced 
solutions” is more firmly grounded than ever. To the experimental 
proof of it for animals in the ingenious experiments of Lors himself 
are added the no less remarkable results of OsTERHOUTS in his work 
on marine as well as freshwater and terrestrial plants, and to both 
of these are now added the results above described on the third great 
class of living organisms which seem to hold the same general relation 
to balanced solutions as the other two. 
: SUMMARY 
1. The ammonifying power of B. subtilis is stronger in artificial 
sea water or in natural sea water of the same concentration than in 
any other salt mixture. : 
2. Sea water may be looked upon therefore as a physiologically 
balanced solution for B. subtilis as truly as it is for animals and the 
higher plants. 
I am indebted to Professor W. J. V. OsteRHouT of Harvard 
University for helpful suggestions and critical reading of the manu- 
script. 
LaBoratTory oF Sor. BACTERIOLOGY 
UNIVERSITY OF CALIFORNIA 
$ Bor. Gazerre 42:127-134. 1906; 44!259-272. 1907. 
