48i< ADDITIONAL REMARKS 



/etfi cTuUmo online included the active jMolecules as well 

 as true Animalcules. 



I may next mention that Gleichen, the discoverer of the 

 motions of the Particles of the Pollen, also observed similar 

 motions in tlie particles of the ovulum of Zea Mays. 



Wrisberg and MiiUer, who adopted in part Buftbn's hy- 

 pothesis, state the globules, of which they suppose all 

 organic bodies formed, to be capable of motion ; and Mid- 

 ler distinf^'uishes these moving* oro-anic o'lobules from real 

 Animalcules, vrith which, he adds, they have been con- 

 fonnded by some very respectable observers. 



In IS 14 Dr. James Drummond, of Belfast, published in 

 the 7th volume of the Transactions of the Royal Society 

 of Edinburgh, a very valuable Paper, entitled " On certain 

 Appearances observed in the Dissection of the Eyes of 

 Pishes.'' 



In this Essay, which I regret I vv as entirely unacquainted 

 with when I printed the account of my Observations, the 

 author gives an account of the very remarkable motions of 

 the spicula which form the silvery part of the choroid coat 

 of the eyes of fishes. 



These spicula were examined with a simple microscope, and 

 6] as opacpie objects, a strong light being thrown npon the 

 drop of water in which they were suspended. The appear- 

 ances are minutely described, and very ingenious reasoning 

 employed to show that, to account for the motions, the 

 least improbable conjecture is to suppose the spicula ani- 

 mated. 



As these bodies were seen by reflected and not by trans- 

 mitted light, a very correct idea of their actual motions 

 could hardly be obtained ; and with the low magnifying 

 powers necessarily employed with the instrument and in 

 the manner described, the more minute nearly spherical 

 particles or active Molecules which, when higher powers 

 were used, I have always found in abundance along with 

 the spicula, entirely escaped observation. 



Dr. Drummond's researches were strictly limited to the 

 spicula of the eyes and scales of fishes ; and as he does not 



