118 Transactions of the Sociehj. 



wliicli reference has already been made, is in its normal state like a 

 cup, terminating in a slender pointed stem. It has nuclear bodies 

 and two large " eye spots," with the strange " rhythmical opening 

 and shutting " seen by these observers in some other monads. It 

 is provided with four long flagella, and the authors say, its mode 

 of locomotion is "a graceful gliding through the water, the 

 flagella moving so often and so rapidly as to render their detection 

 impossible when the monad is at its swiftest. They could roll over 

 on their long axis, and change the direction of their motion with 

 lightning-like rapidity, and, however crowded the field, not the 

 slightest approximation to collision occurred." In this case the 

 creature is big enough for some important internal organs to be 

 seen, but had it been too smaU for this, or had none been open to 

 detection, would not its remarkable and varied powers of locomotion 

 have afforded fair ground for suspecting that it ought not to be 

 ranked among the simplest unicellular bodies ? 



Before passing to another topic, a protest may be admitted 

 against a not uncommon practice of describing some of the lowest 

 living things as composed of a little mass of " homogeneous proto- 

 plasm." Is it not true, whenever magnification reasonably pro- 

 portioned to the size of any organism can be applied, its proto- 

 plasm, so far from being " homogeneous," exhibits granulation, or 

 particles difiering in refractive power, and presumably in chemical 

 properties from the mass ? 



The progress of discovery certainly leads to the belief that the 

 processes and functions of the higher animals are developments of 

 what is found low down in the scale. In a lecture " On the Phe- 

 nomena of Life common to Animals and Plants,"* Claude Bernard 

 said, " the principle of vital unity dominates in the entire history of 

 animals and plants," and he characterized " nutrition" as " continuous 

 generation." In another passage he said, " At the origin of every 

 nutritive or generative phenomenon there is an organized agent, 

 egg, germ, cell," and up to the present time the Spontaneous Gene- 

 ration Controversy has resulted in showing that there are no known 

 means of obtaining any manifestations of new life, excepting as the 

 products and results of previous life, acting, and acted upon, by 

 appropriate surroundings. There is, however, another controversy 

 still going on, in which the Microscope is indispensable, which has 

 very wide and important bearings upon a variety of scientific ques- 

 tions, and which has a better chance of being finally settled. 



This controversy relates to M. Pasteur's explanation of certain 

 facts and appearances belonging to fermentation. In 1861, and 

 since, M. Pasteur has been led by various experiments to divide a 

 group of living organisms into two classes, which he designates 

 aerohies and anaerohies, the former requiring for their existence 



* 'Kevue Scientifiquc,' 26th September, 187i. 



