83 



For G. incurva, to two of the former works ; to the Petrefacten of 



Zieten ; and Parkinson's Organic Remains. 

 For G. suilla, to Goldfuss. 

 For G. obliquata and Macullochii, to Sowerby's Mineral Con- 



chology. 



It is scarcely necessary to observe, that all these works are of so 

 expensive a character, as to place them beyond the reach of the great 

 majority of geological students; that they are all out of print, and 

 not always attainable by those who can afford to purchase them ; 

 hence, therefore, the desirability of carrying out the design we 

 have formed. It will be seen in the sequel, that we shall have 

 occasion to refer to various other supposed species, described by 

 continental authorities. 



The first which claims our notice in stratigraphically ascending 

 order is the Gryphaea incurva, of Sowerby, or arcuata, of Foreign 

 Writers, the latter being the name under which it was described by 

 Lamarck, the typical form of which has been figured by the following, 

 amongst many other authors : — 



Bourget, 1742, Traite des Petrefactions, Paris. Plate 15, 



figure 92. 

 Walcot, 1779, Description of Petrifactions near Bath. P. 51, f. 34. 

 Encyclopedic, 1789. P. 189. 

 G. arcuata, Lamarck, 1801, Systeme des Animaux sans Vertebres. 



P. 398. 

 G. arcuata, Parkinson, 1811, Organic Remains. Vol. III. p. 209, 



P. 59, f. 4. 

 G. incurva, Sowerby, 1815, Mineral Conchology. Vol. II. p. 23, 



P. 112, f. 1, 2. 

 G. arcuata, Lamarck, 1819, Animaux sans Vertebres. Vol. VI. 



P. 198, No. 4. 

 G. incurva, Defrance, 1829, Dictionnaiie des Sciences Naturelles. 



XIX. P. 536. 

 G. arcuata, De Blainville, 1825, Manuel de Malacologie et de 



Conchyliologie. P. 59, f. 4. 

 G. incurva, Zieten, 1830, Die Versteinerungen Wurtemberges. 



P. 65, pi. 49, f. 1. 

 G. arcuata, Deshayes, 1831, Descriptions des CoquiUes Caractens- 



tiqucs des Terrains. P. 98, pi. 12, f. 4, 6. 

 G. arcuata, Goldfuss, 1835, Petrefacta Germanise. PI. 8, f. 1, 2. 

 G. arcuata, Roemer, 1836, Die Versteinerungen des Nord Deutche : 



Oolithengebirges, Hanover. P. 62. 

 G. arcuata, Schmidt, 1846, Petrefacten-Buch. P. 61, pi. 18, f. 3. 



