J. Wyman on living organisms in heated water. 163 
Waters at a very high temperature, within a few degrees even of 
boiling water, the experimenter is called upon to show whether 
water at the boiling point is or is not destructive of life, before 
€ can venture to offer a theory of the origin of the infusoria in 
the flasks. It should not be overlooked that a marked differ- 
ence exists between the conditions of life in the flasks and the 
thermal springs; in the former, the temperature is suddenly 
Taised from that of the air to the boiling point, while in the lat- 
ter, the organisms inhabiting them have become adapted to their 
surroundings through long periods of time. Furthermore it 
must be remembered that in the two cases, we have to deal with 
widely different species. It therefore becomes necessar 
termine by direct experiment on the species of infusoria found 
in the flasks what their powers of resistance are. 
ore proceeding to give the result of the experiments we 
have made, bearing upon this question, we will notice some of 
the statements which are constantly urged in support of the 
°pinion that infusoria are capable of resisting water of a very . 
high temperature. Among ean are the ones relating to the 
well known experiments of Doyére and others, in which Tar- 
digrades and Rotifers are asserted to have resisted a heat of 
#48" F'. In these cases the important condition that the organ- 
was in a dry and not in a moist state is often overlooked. 
Tn truth Doyére himself expressly mentions that in a movst con- 
dition they perished at 122° F.* ; ‘s 
Tn the alleged instances of seeds resisting the action of boiling 
if th 
and this it easily resists., Water penetrates the seeds 0 
Plants and especially of some of the Leguminose very slowly; 
in the case of those of Gleditchia and Laburnum, we have found 
“ates muc are | 
when immersed, and are boiled for a few minutes only, they 
May still germinate. If they are moistened beforehand, the 
action of boiling water has been found uniformly fatal. In one 
of our experiments twenty-eight seeds of Gleiditchia were soaked 
* Annales des Sciences Naturelles, t. xviii, 1842, p. 29. The whole subject as 
attds the resistance of dried Rotifers to heat, was inv 
