OF ARTS AND SCIENCES : FEBRUAKY U, 1865. 393 



nally corresponded with each other, so nearly as Laplace's limits re- 

 quire, by mere accident, but much more probable that they were made 

 to coincide very nearly before solidification, by tidal action, which, I 

 think, has been shown to be an adequate cause for this near coinci- 

 dence. This idea, so far as I know, was first suggested in my paper, 

 in Gould's Astronomical Journal, in the year 1853. The same was 

 also advanced by Helmholtz, in a lecture at Konigsberg, in the year 

 1854. 



The following paper was presented ; — 



Proofs of the Animal Nature of the Cilio-flagellate Infusoria, 

 as based upon Investigations of the Structure and Phi/si- 

 ology of one of the Peridinice (^Peridinium Ci/pripedium, 

 n. sp.'). By Prof. H. James Clark, A. B., B. S. 



Whatever tends to elucidate the doubtful nature of any group of 

 beings which stands undecided (as it were on the dividing line) between 

 sentient and non-sentient things, has an importance, at the present day, 

 which would not have been deemed worthy of very grave considera- 

 tion before the theories of Spontaneous Generation, and what is some- 

 times mistakenly called Darwinism, had been revived. The resurgence 

 of these doctrines has given a prominence to the discussion of the char- 

 acter of the lowest, obscure forms of Ufe, simply because, in their ex- 

 treme simplicity, they hardly seem to rise above a state of inorganic 

 nature, and their vitality is exhibited in such a guise as would readily 

 be mistaken for the operation of exo-endosmotic, inanimate, inorganic 

 forces. Hence the readiness, the eagerness with which the Physicists 

 of the Materialistic school clutch at these " toys " of the older micro- 

 scopists, hoping therein to find an abundance of argument by which 

 they may prove that rock and flesh do not incompatibly jostle each 

 other whenever they come in contact. 



Claiming, and justly too, that these extremes of the inorganic and 

 organic bodies are naturally and incontestably related to each other 

 through their common basis, the simple elements of the chemist, it 

 does not seem possible to the Materialist that their relations should be 

 changed, or dissevered, by the introduction of any modes of existence, 

 however varied or elevated. The Carbon, the Hydrogen, the Nitro- 

 gen, and the Oxygen once being established as definite existences, they 



