THE ANNALS 



AXD 



MAGAZINE OF NATURAL HISTOllY. 



No. 92. NOVEMBER 1844. 



XXXVII. — On a new Genus of Palceozoic Shells. By William 

 KiXG, Curator of the Museum of the Natural History Society 

 of Northumberland, Durham aud Ncwcastle-upon-Tyue. 



To the Editors of the Annals of Natural History. 

 Gentlemen, 

 In a 'IMonograph of the Invertebrate Fossils of the Magnesian 

 Limestone of the County of Durham^ which I am preparing for 

 publication, I have been compelled to institute six new genera, 

 namely, Allorisma for species represented by Sanguinolaria sul- 

 cata, Ph., Struphalosia for a Productus-like shell with an area, 

 and possessing a condyloid hinge as in the Terebratulas, and not 

 a simple one as in the true Productuses; Camerophoria for a 

 Brachiopod approximating to Pentamerus in some points of its 

 internal structure ; Pleurophorus for Area costata of Capt. Brown ; 

 Schizodus for the Permian and carboniferous Axinuses, to di- 

 stinguish them from the London clay Axinus angulatus, and 

 Anthracosia for a group of Unionidce characteristic of the coal- 

 measures. 



In the following paper I liave given the generic character, &c. 

 of Allorisma. 



I may add that the monograph will contain figures of the 

 dental and other characters of all the new genera. 



I have the honour to be. Gentlemen, 



Your very obedient seiTant, 



Newcastle, Museum, Oct. 4, 1844. Wm. King. 



In the carboniferous system of some districts, certain shells 

 abound which are elongated in the direction of their cardinal line, 

 and often marked with deep broad wrinkles running parallel with 

 their free margins. Following J. de C. Sowerby, they have in 

 general been placed in the genus Sanguinolaria, which cannot be 

 continued, since the existing species bearing this name are fur- 

 nished with teeth which are absent in the carboniferous shells. 



An examination of several of these fossils has convinced me 

 Ann, ^ Mag. N. Hist. Vol. xiv. Y 



