SECTION IV. 9^ 



t2. Murices. 13. Purpurae. 14. Buccina* 

 and 15. Sea Ears. AH thefe families, fays 

 he, proceed from a fpiral, which extends 

 or widens more or lefs. 



In the above work, as he mentions the 

 fpiral form only, he has neither placed 

 the Vermiculi or the Limpets. How- 

 ever, in his fyftem he has given Ibme fi-^ 

 gures of the former ; but of the latter, or 

 Limpets, he has neither figured or men- 

 tioned a fingle fpecies, in his whole work ; 

 which is very remarkable. 



Breynius divides all Shells into two gc* 

 neral diviiions of tubular or vafcular : that 

 is, into Shells that are hollow, or like 

 tubes, and into thofe that are like cups 

 or veffels. The firft divifion he fubdi- 

 vides into Monothalamias, or of one ca- 

 vity ; and into Polythalamias, cham- 

 bered, or with many cavities. The fe- 

 €ond into fimple, as the Limpets ; or com- 

 pofit, as the Bivalves and Multivalves. 

 On this fcheme he forms eight principal 



clafles 



