178 Dr. Maton's and Mr. Rackett's 



valves, and the aperture, or mouth, of univalves, as it was a 

 permanent character, so was it also less multiform than any other 

 that could have been chosen. The general outline, however, was 

 not wholly neglected. Tt served to form an uniting character for 

 such as may be called natural families of shells, which were dis- 

 tributed into suitable divisions, subordinately to the artificial 

 genus, so as to become an assistance instead of an embarrassment 

 in the investigation of species. Thus, the terms trnncati, pyri- 

 formes, elongati, and laxi, became useful demarcations in the 

 genus Conns, without creating the confusion which must always 

 be incident to too great a number of regular genera, especially 

 when those genera are formed (as was the practice of the genera- 

 lity of preceding authors) from external figure only. In a few 

 genera it was necessary to deviate a little from these principles, 

 (and what system can be free from anomalies ?) yet they are too 

 few to affect the general simplicity, and we ought to be surprised 

 only at the characters holding good so far as they do. But our 

 great author was not wholly inattentive to the creatures for which 

 the beautiful and endlessly diversified receptacles that he had 

 characterized were designed. Among the generic marks was in- 

 cluded the name of the molluscous inhabitant; or, where the ani- 

 mal differed from any which had a place in other parts of his 

 system, he described it at length. Thus was a method established, 

 which, though not speculatively regular, possesses so much prac- 

 tical utility that we cannot hesitate to prefer it to any hitherto 

 made known to the world. Whatever improvements it may un- 

 dergo (and of improvements all human systems must necessarily 

 be susceptible), there is in our minds no doubt that the general 

 foundations will stand the test of scientific application for ages ; 

 a sentiment which will appear the less bold, if we quote in aid of 

 our assertions those of a very distinguished naturalist of a neigh- 

 bouring 



