382 Intelligence and Miscellaneous Articles. 



the time which perhaps might be occupied more usofully in study, 

 M. Cuvier first states the circuaistances which have brought on 

 this discussion. 



Two young and ingenious observers studying the respective 

 position of the viscera of the Cephalopoda, thought that perhaps 

 among these viscera migiit be found an arrangement resembling 

 that which exists among the Vertebral a, if we represented to our- 

 selves the cephalopodous animal as a vertebrated one, whose trunk 

 was folded on itself backwards at the height of the navel, in such a 

 way that the pelvis should fall on the neck. " One of our learned 

 colleagues," continues M. Cuvier, "eagerly seizing this novel view, 

 has announced that it completely refutes all that 1 had said respect- 

 ing the distance which separates theMollusca from the Vertebrata. 

 Going even much further than the authors of the memoir, he has 

 concluded from it that zoology has not had until now any solid 

 basis ; that it has been nothing but an edifice constructed on the 

 sand ; and that its only indestructible base for the future is a cer- 

 tain principle which he calls unity of composition, and which he 

 asserts to be capable of an universal application." 



M. Cuvier, being determined to discuss the reality of this princi- 

 ple, began by examining the question in its particular relation to 

 the Mollusca. 



Now first of all it is best clearly to define the terms, and to deter- 

 mine what we are to understand by the expressions ' tinity of com- 

 position,' ' unity of plan.' W the words were taken in their most ri- 

 gorous acceptation, it could not be said that there is unity of com- 

 position in two kinds of animals, only except in so far as they are 

 composed of the same organs: so likewise to prove that there is 

 unity oi plan in their organization, it would be necessary to show 

 that these identical organs are disposed in the same order in both. 



But it is impossible to suppose that the naturalists who speak 

 oi unity oj composition, of unity of plan, in the whole of the animal 

 kingdom, should have understood things thus, or that they should 

 have wished to maintain that all animals are composed of the same 

 organs, arranged in the same manner. 



Now the terms being thus defined, the principle of unity, re- 

 stricted as it ought to be, appears incontestably true ; but it is very 

 far from being new. It forms, on the contrary, one of the bases 

 upon which zoology has reposed ever since its origin, — one of the 

 principles upon which Aristotle, its creator, has placed it, — a basis 

 which all zoologists worthy of that name have sought to enlarge, 

 and to the confirmation of which all the elForts of anatomy have 

 been devoted. 



Thusevery day might be discovered in an animal some part which 

 was not before known to exist in it, and which enables us to seize on 

 some additional analogy between that animal and tliose of different 

 generaand classes. Tlic same may be liie case with respect to connec- 

 tions ofnewly-pcrctiscd relations. Labours undertaken in this direc- 

 tion are eminently useful, and those of .M. GeoH'ro^-St.-llilaire in 

 particular are worthy of all the esteem of naturalists. W hen, for 



instance. 



