PROTOZOA. 19 



the tenacity with which the smaller rotifer retained its 

 hold ; for although one might think that it was being 

 almost jerked to pieces, after each bout of jerking it was 

 seen to be still attached. This trial of strength, which 

 must have involved an immense expenditure of energy in 

 proportion to the size of the animals, lasted for several 

 minutes, till eventually the small rotifer was thrown 

 violently away. It then returned to the conflict, but did 

 not succeed a second time in establishing its hold. The 

 entire scene was as like intelligent action on the part of 

 both animals as could well be imagined, so that if we were 

 to depend upon appearances alone, this one observation 

 would be sufficient to induce me to attribute conscious 

 determination to these microscopical organisms. 



But, without denying that conscious determination may 

 here be present, or involving ourselves in the impossible 

 task of proving such a negative, we may properly affirm 

 that until an animalcule shows itself to be teachable by in- 

 dividual experience, we have no sufficient evidence derived 

 or derivable from any number of such apparently intelli- 

 gent movements, that conscious determination is present. 

 Therefore, I need not wait to quote the observations of 

 the sundry microscopists who detail facts more or less 

 similar to the above, with expressions of their belief that 

 microscopical organisms display a certain degree of instinct 

 or intelligence as distinguished from mechanical, or wholly 

 non-mental adjustment. But there are some observations 

 relating to the lowest of all animals, and made by a com- 

 petent person, which are so remarkable that I shall have to 

 quote them in full. These observations are recorded by 

 Mr. H. J. Carter, F.R.S., in the 'Annals of Natural 

 History,' and in his opinion prove that the beginnings of 

 instinct are to be found so low down in the scale as the 

 Rhizopoda. He says : ' Even Athealium will confine 

 itself to the water of the watch-glass in which it may be 

 placed when away from sawdust and chips of wood among 

 which it has been living ; but if the watch-glass be placed 

 upon the sawdust, it will very soon make its way over the 

 side of the watch-glass and get to it.' 



This is certainly a remarkable observation : for it seems 



