15 



When tlie surface of this shell is deprived of its fringes, 

 which it mostcoramonly is, it appears to be concentrically 

 striated : the even, very convex surface and pointed beak 

 distinguish it from At. Jiinbriata, fig. 4. Abounds in the 

 mountain limestone of Bolland ; the figured specimens are 

 in Mr. Gilbertson's Museum, except that with the fringes, 

 which is from Ireland; it is out of a small mass of lime- 

 stone, to which the fringes adhere. 



A figure strongly resembling this shell accompanies a 

 paper by M. Verneuil upon some interesting Brachiopods 

 of the old formations (in the Bulletin de la Societe Geolo- 

 gique de France, torn. xi. 259) ; but as he has referred it to 

 Terehratula {Atrpya) Roissyi, it must be a different thing; 

 the T. Roissi/ih^s the front elevated ; it is Spirifera globula- 

 ris of Phillips. 



ATRYPA planosuicata. 



TAB. DCXYU.—Jig. 2. 



Spec. Char. Pentahedral, rounded^ depressed, the 

 middle of each valve longitudinally planosulcate; 

 surface covered with broad wavy fringes. 



Syn. Spirifera planosuicata. Phill. loc. cit. 220. 

 PL X.f. 15. 



A SPECIES well distinguished by its pentagonal form and 

 waved fringes. The central figure represents a fragment 

 of limestone, upon the surface of which is displayed one 

 fringe nearly perfect, and portions of several others on the 

 edge ; it is one of the most instructive specimens that en- 

 rich Mr. Gilbertson's collection, from which the other 

 figures were also taken. It is also found in Ireland. 



