51 



SERPULA prismatica. 



TAB. DCXXXW.—fg. 5. 



Spec. Char. Linear, four-sided, minute ; lines of 

 growth strong, bent acutely over the angles. 



Syn. Vermilia angulata, Morris, Catal. 67. 



Although the fragment of this shell be very imperfect, 

 it is easily distinguished as a species by its square form. 

 Discovered in the clay at Chalk Farm by Mr. Wetherell, 

 whose patient attention to the minute fossils of the London 

 clay is so well known. 



SERPULA trilineata. 



TAB. DCXXXIV.— /g. 6. 



Spec. Char. Linear, attached throughout, tor- 

 tuose, minute ; attached surface broad ; on 

 the back are three slightly elevated keels. 



Syn. Vermilia trilineata, Morris, CataLGl. 



r ixED upon Terebratula striatula, found at Chalk Farm 

 by Mr. Wetherell. 



SERPULA heptagona. 



TAB. DCXXXl\.—fg.7. 



Spec. Char. Cylindrical, with seven keels ; free 

 except near the apex, where it is conical, with 

 3 to 5 keels curved and attached ; lines of 

 growth strong; keels often expanded into 

 variously undulating \\ings. Operculum fun- 

 nel-shaped, its disc radiated. 



