SECTION XL 237 



The method of Mr. Tournefort, which 

 this author gives, divides all hivalves into 

 two parts. Firft, Such as (hut clofe all 

 round ; and, fecond, fuch as are always 

 open or gaping in fome part. This di- 

 vifion, though good, is incomplete, and 

 his families and genera are very arbitrary. 



Linnaeus offers next. This celebrated 

 naturalift divides all Bivalves into fourteen 

 families, which he charadlerifes by their 

 hinges in a very accurate manner; and 

 his method feems to be the moft perfe<5l 

 yet publiflied. As I (hall have occafion to 

 recite this author's genera in collation with 

 my own, I will enlarge no farther at pre- 

 fent on his arrangements. 



Mr. Davila forms fix families of Bi-* 

 valves, viz. i. Oyfters. 2, Efcallops. 3. 

 Chamae. 4. Heart Cockles. 5.Tellens, and 

 6. Mufcles : but all is very arbitrary and 

 confufed. 



Mr. 



