468 Mr. G. B. Sower by's Remarks 



a loss to imagine ; he does however seem, by his specific name 

 anomala, to have doubted the propriety of placing it in that 



genus. 



I now close my observations upon this subject, only adding the 

 specific characters of the 0. norvegica, and the newly-discovered 

 species which I designate 0. lavis. 



Orbicula l&vis. 

 O. valvulis tenuibus laevibus. 



Tab. XXVI. /. 1. 



Habitat in mari, saxis adherens. 



Orbicula norvegica. 

 O. valvula superior striis plurimis elevatiusculis ex vertice ad 

 marginem decurrentibus. 



Tab. XXVI. /. 2. 

 Syn. Lamarck Anim. sans vertebr. 



Miilhr Zool. Dan. i. t. 5. p. 14. Patella anomala. 

 Habitat in mari, ad littora, saxorum in cavitatibus affixa. 



Obs. When any part of the lower valve does not lie close to the 

 stone, the radiating striae may be perceived decussating the 

 striae of growth. ^.^^j .i 



The following observations, principally upon the genus Crania 

 of Lamarck, will be found to be in a great measure connected 



" The shell is very small, sprinkled all over with elevated points, which make it rough 

 to the touch : its upper valve is larger, and has a projecting apex ; the lower valve ad- 

 heres to old shells and other hard substances in the depths of the North Sea. 



" The animal which inhabits it is represented by two red masses, with two elon- 

 gated arms, blue and fringed ; the fringes thick, rather curled, yellow. It seems that 

 Muller had not the means of observing it with sufficient accuracy, for he does not de- 

 scribe it with that precision which is generally observable in all his writings. He does 

 not even speak of the hinge, of which it is true that he had no suspicion according to 

 the idea which he had formed of the genus of the shell." Bosc, vol. ii. p. 243. 



with 



