SP ONTANE US GENERA TION. 



87 



of new matter endowed with living properties. The question is tlms 

 stated : " It must be considered to turn almost wholly upon the possi- 

 bility of the de novo origin of bacteria ; since, if such a mode of ori- 

 gin can be proved for them, it must also be conceded for other allied 

 fungoid and algoid units. Evidence, which is of the most convincing 

 character when looked at from all sides, now shows that bacteria are 

 hilled by a temperature of 140 Fahr. Yet similar organisms will con- 

 stantly appear and rapidly multiply within closed flasks containing 

 organic fluids, although the flasks and their contents have -been pre- 

 viously exposed for some time to a temperature of 212 Fahr." 



As it will be impossible in this article to give the details of Dr. 

 Bastian's experiments, we will try to convey to our readers some no- 

 tion of these living organisms, which it is now claimed can be pro- 

 duced when all germs are destroyed. When a fluid containing an or- 

 ganic substance in solution is left to itself for a time, which may be 

 variable in different circumstances, the infusion gradually becomes 

 turbid, and there forms upon its surface a thin, semi-translucent scum, 



Fig. 2. 



Representation op Haeckel's Group Monera. ( x 800.) The Common Amceba. 



a. Minute Specks of Protoplasm from Fine Surface Mud of Fresh-water Ponds ; b. Protomoeba Primitiva, 

 two Individuals resulting from a Recent Fission ; o. Vampyrella Pendula ; d. Amoeba Porreta, a Form 

 of Protomcoba. 



or pellicle, that soon thickens into a membrane. If the fluid be ob- 

 served by a microscope of the highest power, when it first begins to 

 grow clouded, it will be found swarming with multitudes of moving 

 specks or spherical particles (Fig. 1, A),varying from 2 \ Q to 1 q 00 q 

 of an inch in diameter. These specks have been variously named. 



39 



They have been called " monads," or " mycrozimes," or " micrococci, 

 and are termed by Dr. Bastian piastre particles. They are regarded 

 by him as the primordial particles of living matter, and as giving ori- 

 gin to organisms of a higher grade. 



Among these are the infusorial objects known as bacteria (Fig. 1, B). 

 These are minute, rod-like, jointed bodies, varying in size according to 



