OF CONCHOLOGY. 97 



from the collection of the Testaceolo- 

 gist. I shall give an extract from 

 the eighth vol. of the LinneanTransac- 

 tions, being the concluding paragraph 

 of the catalogue of British shells, the 

 joint labours of Dr. Maton and the 

 Rev. Mr. Rackett ; which is a work of 

 great merit, and indispensable to the 

 collector of British shells. 



" We venture so far to dissent from 

 the great authority of Linneus, as to 

 exclude from this descriptive cata- 

 logue of British Testacea the genus 

 Sabella. The animals included under 

 that genus, have for their coverings 

 particles of sand agglutinated on the 

 external membrane, and resemble 

 rather the larvce of certain insects, 

 than the testaceous vermes. The lat- 

 ter form their calcareous integuments 

 entirely from the secretions of their 

 own surfaces, and are attached to these 

 by cartilaginous processes, so as to 



render them essential and indispen- 

 o 



