PLATE XCI. 



A newly-discovered species of the Pecten tribe that inhabits the 

 seas of Van Dieman's Land, and which has only been very lately 

 introduced to the knowledge of European naturalists. The specimen 

 in our cabinets, the subject represented in the annexed plate, was 

 transmitted to England with other shells, the production of Van 

 Dieman's Land by Mr. Humphries, a resident in that part of the 

 soulhern hemisphere, and one to whose attention as a collector we 

 are indebted for many other novelties of the same nature that are 

 equally new and interesting to the science. 



Among the number of the testaceous productions that inhabit 

 the seas surrounding the British Isles, we possess two species of the 

 Pecten tribe that may appear to the inexperienced amateur as bear- 

 ing a very close resemblaDce to the present shell, and which perhaps 

 without due examination might be mistaken for and confounded with 

 it. The first is the Ostrea suhrufa^ and the other Ostrea Monoetis 

 of our British Conchology ; we do not mean that either of those shells 

 in the younger state could be so far misconceived, but there are 

 transitions in the growth of the older shells, when the more minute 

 distinctions of their rays and other peculiarities are v/orn away or in 

 part obhterated, that would render it rather more difficult to dis- 

 tinguisli them than in their young and uninjured state, and this the 

 more especially since our present shell presents some characteristic 

 features of both, and indeed forms an intermediate species between the 

 two. On duly comparing those three species, and we have examples 

 of each at this time before us, we can scarcely hesitate in denomi- 

 nating our present shell an intermediate link in the chain of species ; 

 it is smaller than the larger growth of Ostrea subrufa, and larger 

 than Ostrea monoetis In the form or contour the shell is less orbi- 



