408 PYRAMIDELLID.E. 



species it is often strong, slender, small, prominent and re- 

 tired. Such characters cannot fail to mislead and confuse 

 the young student. 



The first and best characters of a Chemnitzia are undoubt- 

 edly the malacological ones we have given above, when they 

 can be had ; the next are of conchological value, the inflected 

 apices; which however will almost always shadow out what 

 the animal of a shell will prove; and the tooth, however 

 minute and rudimental, is an excellent aid ; and we may add, 

 the flap or process of the operculum. All others, from their 

 instability, lead to error and confusion ; but if they are brought 

 forward as specialties, it should be sub modo, with explanatory 

 guards and limits, and indications of their variableness. 



I now approach the catalogue raisonne, and will include 

 with it the additions and new matter under the titles to which 

 they belong. Perhaps it may be conceded that a sedulous 

 examination of these interesting objects for more than forty 

 years, has in some measure placed me in a position to offer a 

 reformed list of the British Chemnitzite, which will include all 

 the animals, with our denned characters, whatever may be the 

 form and sculpture of their testaceous habitations. To accom- 

 plish what I have proposed, my own cabinet affords large 

 facilities, and my friend Mr. Bailee has kindly taken the 

 great trouble to consign to me for inspection, from Falmouth, 

 his rich tablets of accredited examples of those species I do 

 not possess. These aids and appliances have increased my 

 confidence that perhaps I may succeed in offering such a 

 relieved and moderated list of the objects of this important 

 genus, as will place within just limits the genuine indigenous 

 Chemnitzice of our Isles. We do not pretend to perform this 

 task without error. Who, on such a subject, can avoid occa- 

 sional misconceptions ? We can only try conscientiously to 

 perform our duty ; but, alas ! even in the midst of these de- 

 lightful studies and recreations, the bit of bitter will spring 

 up. How admirably has the inimitable Lucretius illustrated 

 this inevitable ingredient in all human affairs, and told us 

 that the attempt to evade the thorns of this destroyer of our 

 peace is vain and fruitless ! 



