PLATE C1X. 



In deciding a question of some moment to the English Concho- 

 logist, it has been thought advisable to give an additional Plate of 

 Murex Antiquus, by which the difference between the two shells may- 

 be more easily discriminated. We must however observe, that the 

 latter is not absolutely known as a British shell ; it is a native of the 

 North Seas, and has been supposed to inhabit some of the remote 

 northern islands of the British dominions. The Murex Antiquus of 

 Pennant is a very different shell, and by no means allied to that of 

 Linnseus, whose name it bears. 



It is now uncertain from what part of our coast the Duchess of 

 Portland received this shell ; Pennant is silent in this respect, but we 

 cannot dispute that her Grace received it as a British shell, since k 

 was inserted upon her authority in the British Zoology. 



A 3 



