Mr C. Collier on Univalves. 225 



lymph, the property which the nerves possess of transmitting 

 sensibility, the property which the muscles have of contracting, 

 the action of the gastric juice in digestion, the opposite qualities 

 of the red and black blood, &c. ? " I speak not of the twenty 

 discoveries made in our own day ; it is well known that a dis- 

 covery, before it can be admitted, must be of old date, and, as 

 father Malebranche said, must have a venerable beard." 



There is every reason to hope, said M. Flourens in conclud- 

 ing, that the ideas which I have just thrown out with respect 

 to the improvement which human medicine may expect from 

 experiments made on animals, will not be despised in our days ; 

 for no person is now ignorant that every thing is connected in 

 the animal economy, the diseases, the functions and the organs, 

 that we can only act upon the diseases by the functions, on the 

 functions only by the organs, and that thus therapeutics is 

 founded upon physiology, and physiology upon the economy. 



General Observations on Univalves. By Charles Collier, 

 Esq. Staff-Surgeon at Ceylon. Communicated by Sir James 

 Macgrigor,' Director-General of the Army Medical Board, 

 F. R. S., &c. &c. 



JLt was my intention, at one time, to propose an arrangement 

 and a nomenclature of shells, founded rather on the features 

 and structure of the inclosed moUusca, than on the shells them- 

 selves. The difficulties to be encountered in the execution of 

 such a design are, however, too many and too great to render it 

 conducive to any useful result, or availing for the furtherance 

 of general knowledge. Many mollusca, alike in form and struc- 

 ture, inhabit shells so essentially different in character, as to 

 render the union of the two modes of distinction impossible. 

 Besides, it deserves consideration, even if this union could be ef- 

 fected, that Conchology will always be studied by many who 

 take no interest in the comparative structure of animals, and 

 who could derive little advantage from the knowledge of shells, 

 were it necessary to be acquired with the anatomy of the inhabi- 

 tant. 



Subjoined arc a few facts derived from my own research, 



