33(5 



of a class, so as to enable the student to deposit his objects 

 with certainty in their natural position, and to distinguish 

 them from others, however numerous, of the same family, by 

 concise and well-defined specialties. If these rules were 

 rigorously attended to, we should have fewer complaints of 

 the almost impossibility of identifying many of the objects of 

 natural history. The inconveniences that have arisen from 

 the neglect of these precepts are so great and pressing, that I 

 propose to attempt to point out their origin, and suggest a 

 remedy as far as regards malacology and conchology, and to 

 evidence and illustrate my arguments by references to the 

 present state of certain groups of the Mollusca. If concho- 

 logists are determined to form numerous species from the 

 same animal because it happens to present certain shell-varia- 

 tions, they must have their way, but malacologists will not 

 concur with them in giving a dozen names to the same object. 

 These gentlemen cannot escape having the phrase " Dies do- 

 cebit" verified ; the day of retractation will assuredly arrive ; 

 it will therefore be better for the interests of science and their 

 amour propre, at once to apply the remedy for this singular 

 creative monomania, 



. . . . "O medici mediam pertundite venam." 



I apologise for my irreverent quotation, and trust I may claim 



for this once, 



" Liberius si 



Dixero quid, si forte jocosius, hoc mini juris 

 Cum venia dabis." 



The practice I have just described is fraught with great 

 detriment to the advancement of science, because in many 

 instances it destroys every attempt at identity, and renders 

 our books bulky and expensive, by the insertion of worthless 

 synonyms, which have no existence as objects; and every 

 writer feels obliged to notice all, because he has not the means 

 of separating the rigorously-defined and well-founded species 

 from the pseudo and unsubstantial articles. It results from 

 this false position of the science, that when a student, with his 

 object in hand, consults the authorities, he finds ten or twelve 



