172 ANIMALS AND PLANTS. 



this want of faith, I have thought a good deal over the 

 matter; and as I still rest in the lame conclusion I 

 originally expressed, and must even now confess that I 

 cannot certainly say whether this creature is an animal 

 or a plant, I think it may be well to state the grounds 

 of my hesitation at length. But, in the first place, in 

 order that I may conveniently distinguish this " Monad " 

 from the multitude of other things which go by the 

 same designation, I must give it a name of its own. I 

 think (though, for reasons which need not be stated at 

 present, I am not quite sure) that it is identical with the 

 species Monas lens, as defined by the eminent French 

 microscopist Dujardin, though his magnifying power was 

 probably insufficient to enable him to see that it is curi- 

 ously like a much larger form of monad which he has 

 named Heteromita. I shall, therefore, call it not Monas, 

 but Heteromita lens. 



I have been unable to devote to my Heteromita the 

 prolonged study needful to work out its whole history, 

 which would involve weeks, or it may be months, of 

 unremitting attention. But I the less regret this cir- 

 cumstance, as some remarkable observations recently 

 published by Messrs. Dallinger and Drysdale * on certain 

 Monads, relate, in part, to a form so similar to my Het- 

 eromita lens, that the history of the one may be used to 

 illustrate that of the other. These most patient and 



* " Researches in the Life-history of a Cercomonad : a Lesson in Bio- 

 genesis ; " and " Further Researches in the Life-history of the Monads/' 

 " Monthly Microscopical Journal," 1873. 



