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



the title of Ilhtoria ShnpUc'iiim. The testaceoh)gical remarks are 

 extremely superficial, and defective in originality. 



RICHARD BRADLEY, 



though not a professed testaceologist, has not altogether omitted 

 this order of animals in his " Philosophical Account of the IVorks 

 of Nature" and his figures of the species, though few and scat- 

 tered, are not uuAvorthy of being referred to. This work in its 

 day must have been considered as an interesting view of the 

 oeconomy of nature, being judiciously written, and illustrated by 

 a considerable number of accurate engravings. 



Hitherto system in testaceology had made but little progress. 

 That of Buonanni was almost tlie only one which can be said to 

 have been fully and philosophically exemplified, and its outline 

 was more or less preserved in most succeeding attempts ; but its 

 defects and errors, as we have before remarked, were numerous. 

 After having noticed a multitude of mere describers, Ave now 

 come to an author who is not undeserving of the title of a scien- 

 tific one, and whose system, so far as marine Testacea are con- 

 cerned (and of these alone he treats), certainly glances at the 

 great clue to simplicity, which was afterwards so successfully and 

 admirably seized by the great reformer of natural history in ge- 

 neral. The author alluded to is 



LANGIUS. 



He is the first whose generic characters are founded on com- 

 modious distinctions, the aperture of univalves, and the hinge of 

 bivalves, being particularly considered. These distinctions, hoAv- 

 ever, are not allowed their due importance throughout; for the 

 contour of the shell is, in many instances, made the exclusive 

 basis of the definition, and the adoption of this naturally led, as 



in 



