34 MOLLUSCA. 



to perfection the artificial system of conchology, and have 

 formed their arbitrary characters, independent of the habits 

 of life of the contained animal. But the naturalists whom 

 we have now to consider, have traced these animals to their 

 lurking places, and arranged them according to the situation 

 in which they reside, instead of the forms which they ex- 

 hibit. 



At the head of this class of conchologists, Dr. Martin Lis- 

 ter stands pre-eminently conspicuous. His great work, en- 

 titled Historia sive Synopsis Methodica Conchylwrum, was 

 begun in 1685, and completed in 1692. It will long remain 

 a monument of the extensive information and unwearied 

 diligence of its author. The following synoptical view of 

 the work will enable our readers to comprehend its plan ; the 

 original should be consulted with care. 

 Lib. i. De Cochleis terrestribus. 

 Pars 1. De Buccinis terrestribus. 

 Pars 2. Cochleae nudae terrestres Limaces quibusdam 



dictae. 



Lib. ii. De Turbinibus et bivalvibus aquae dulcis. 

 Pars 1. De Turbinibus. 

 Pars 2. De Testaceis bivalvibus fluviatilibus. 

 Lib. iii. De Testaceis bivalvibus marinis. 



Pars 1. De Testaceis bivalvibus, imparibus testis. 

 Pars 2. De Testaceis bivalvibus, paribus testis. 

 Pars 3. De Testaceis multivalvibus. 

 Lib. iv. De Buccinis marinis, quibus etiam vermiculi. 



dentalia et patellae numerantur. 



The plan followed by Sir Robert Sibbald in his Scotia 

 Illustrata is somewhat different from that of Lister. He 

 divides the Testacea into two classes, land and water shells, 

 and the latter class he subdivides into fluviatile and marine. 



