10 DUNDEY GASTEROPODA. 



obtamcd by the collation of three collections, amounts to only 

 eighteen species, of which two were undetermined, viz : — 

 Cirrus nodosus Pleurotomaria armata 



Leachii punctata 



Littorina ornata sulcata 



sp. proteus 



T^erinea anglica Monodonta laevigata 



Pleurotomaria omata Alaria Phillipsii 



abbreviata Chemnitzia lineata 



elongata Turbo Milleri 



fasciata Trochus sp. 



Two of these we shall see must be merged into one, so that, the 

 total remaining will be seventeen species. 



Our own results differ somewhat widely from this. Prom our 

 own Museum we obtain a total of sixty-six species in a determinable 

 condition, besides casts and imperfect fragments of shells. Of the 

 genus Pleurotomaria alone there are twenty-six species. 



The total is more than double those in the catalogue of the 

 Museum of Practical Geology, and which are drawn from the 

 whole kingdom. 



We may therefore call our Museum rich in Inferior Oolite 

 Gasteropoda. Dr. Wright (loc. cit.) gives a much fuller list 

 however, viz., forty species from Somersetshire, besides three or 

 foar from other localities. This tallies much better with the 

 result of our examination. 



Quenstedt (Jurr, p. 414) has lamented the number of species 

 which D'Orbigny makes in the genus Pleurotomaria. Though 

 anxiously on the look out for transitional forms, which would 

 enable us to unite under one species what had before been 

 kept separate, we are bound to say our opinion is, from a com- 

 parison of Dundry specimens, that the greater number of 

 D'Orbigny's species must be upheld for the present. If it be said 

 that he goes too much into minutiae of surface ornament and so on, 

 we must rejoin that a neglect of similar details among recent 

 MoUusca would prevent us separating what we know from the 



