XXVIT. ANCYLUS. FRESH-WATER 

 PATELLA. 



So called from the close connexion by which the cir- 

 cumference of the shell is fixed to its attachment ; 

 or perhaps from the conical point, resembling the 

 handle of a cover ; in which case it should be 

 written Ansulus or Ansylus, 



125. Ancylus fluviatilis. River Patella. 



126. Ancylus lacustris. Lake Patella. 



The Author is here desirous to make an observa- 

 tion concerning names. When he called the shell 

 discriminated by his daughter, Turho Turtonis, it was 

 loudly proclaimed that he had forgotten his Grammar ; 

 for that all names ending in on should pass through 

 the Roman terminations of us and i. And that this 

 supposed error should be fully and publicly corrected, 

 Mr. Sowerby has thought it proper to denominate 

 the new Genus, Galeomma Turtoni. These things 

 are, however, usually arbitrary, as the learned Selden 

 has dedicated his Carmen protrepticon. Ad Ben, 

 Jonsomum : and the only rule in grammar by which 



