Serpula. 



ANNELIDA. 



S. carinella. Sowerby, YI. p. 201, pi. 508, fig. a. 



Cylindrical, adherent, tortuous, gradually tjipering towards 

 the apex ; a small longitudinal keel, becoming obsolete towards 

 the aperture. 



The Greensand, Blackdown. 



3. Serpxtia compressa. — The Compressed Serpula, pi. 

 XCVITI. fig. -26. 



S. compressa. Sowerby, VI. p. 201, pi. 598, fig. S. 

 Lanceolate, somewhat compressed, rapidly diminishing, and 

 smooth ; very slightly tortuous ; a portion of the tube free. 

 The Carboniferous Limestone, Lothian and Ireland. 



4. Serpula antiquata. — The Antiquated Serpula, pi. 

 XCVIII. fig. 40. 



5. mitiquata. Sowerby, VI. p. 202, pi. 598, fig. 4. 

 Cylindrical, very gradually decreasing, surface uneven, with 



transverse, irregular rings ; a portion adherent, by an expan- 

 sion of the tube ; margin of the aperture obtuse. 



The Upper Greensand, Kent, Dorsetshire and Wiltshire ; the 

 Chalk, Hunstanton and Dorking, and the Lower Greensand, 

 Isle of Wight and Kent. 



5. Serpula coktracta. — The Contracted Sei-pula, pi. 

 XCVIII. fig. 34. 



5. contracta. Woodward, Geo. Nor. pi. 5, fig. 19. 



Tube circular, gradually decreasing, considerably and abruptly 

 contracted at the smaller end. 

 The Upper Chalk, Norwich. 



6. Serpula tenuis. — The Thin Serpula, pi. XCVIII. figs. 

 9, 10. 



iS. tmuis. Sowerby, VI. p. 202, pi. 598, fig. 5. 



Cylindrical, with a very minute keel upon the back, and a 

 few distinct acute rings ; substance of the shell thin ; occurs 

 in groups, and either attached to each other or to extraneous 

 bodies. 



The Fresh Water Formation, Hordwell. 



7. Serpula tricarinata. — The Three-Keeled Serpula, pi. 

 XCVIII. fig. 28. 



S. tricarinata. Sowerby, VI. p. 220, pi. C08, figs. 3, 4. 



Aperture generally turned back, surface somewhat smooth, 

 with three thick uninterrupted keels, the central one largest ; 

 sometimes becoming obsolete ; aperture circular, furnished 

 with two thickened lobes at the base ; edge thin. 



The Kimmeridge Clay, near Leighton, Buckinghamshire, and 

 the Calcareous Grit, Shotover Hill. 



«. Serpula triangol.ata. — The Triangular Serpula, pi. 

 XCVIII. fig. 42. 



S. triaitgulata. Sowerby, VI. p. 227, pi. COS, fig. 7. 



Somewhat rounded, smooth, triangular upon the back ; the 

 central angle elevated into a keel ; surface with circukr lines 

 of growth ; always adherent. 



The Great Oolite, Bradford, Wiltshire. 



9. Serpula eu.n-cixata.— The Saw-like Serpula, pi. XCVIII. 

 fig. 35. 



S. runcinata. Sowerby, VT. p. 227, pi. 608, fig. 0, 

 Sub-triangular, tortuous, with three regularly and strongly 



serrated longitudinal keels upon its back ; aperture round ; 



base expanded. 



The Coral Rag, Shotover Hill. 



10. Serpula obtusa.— The Obtuse Serpula, pi. XCVIII. 

 fig. 6. 



S. obtusa. Sowerby, VI. p. 228, pi. 008, fig. 8. 



Obtusely quadrangular, smooth, with an obtuse, thick keel 

 along the back, which is flattened ; edges of the margin pro- 

 duced as a short cylinder, beyond the margin, which is bilobate 

 and thickened ; base expanded. 



The Middle Chalk, Saham, Norfolkshire. 



11. Serpula fluctuata. — The Fluctuating Serpula, pi. 

 XCVIII. flg. 35. 



S. fluctuata. Sowerby, VI. p. 228, pi. 608, fig. 5. 



Circular, surface smooth, with five regularly undulating 

 wire-like low keels ; surface of attachment small. 



The Upper Chalk, Norwich, and the Middle Chalk, Swaff- 

 ham, and Dorking. 



12. Serpula tetragona. — The Tetragonal Serpula, pi. 

 XCVIII. fig. 12. 



Sowerby, VI. p. 203, pi. 599, figs. 1, 2. 



Tube very long, narrow, and for the gi-eater part of its length, 

 unattached ; foui'-sided and nearly flat externally, with promi- 

 nent angles ; aperture round. 



The Kimmeridge Clay, Clophill, Bedfordshire. 



13. Serpula rustica. — The Eude Sei^pula, pi. XCVIII. 

 fig. 11. 



S. rustica. Sowerby, VI. p. 203, pi. 599, fig. 3. 



Tube quadrangular, the angles obtuse ; as the tube increases 

 in length, the angles become variously curved and interrupted, 

 and finally assume the form of irregular nodules, surrounding 

 the tube, which becomes cylindrical. 



The Upper Greensand, Folkstone. 



14. Serpuia articulata. — The Articulated Serpula. pi. 

 XCVIII. fig. 23. 



Sowerby, VI. p. 204, pi. 599, fig. 4. 



Tube quadrangular, provided with rings, each having four 

 oval tubercles, situate at distant irregular intervals; angles 

 rounded ; aperture circular. 



Tlie Gualt, Folkstone. 



15. Serpula vertedbalis.— The Vertebral Sequda. pi. 

 XCVIII. fig. 75. 



S. vertebralis. Sowerby, VI. p, 204, pi. 599, fig. 5. 

 Tube quadrangular, with obtuse longitudinal tubercles, set 

 in rings, at short regular distances, four on each ring. 

 The Oxford Clay, Christian Malford. 



16. Serpula carisata.— The Keeled Serpula, pi. XCVIl 1 

 fig. 29. 



S. carinata. Woodward, Geo. Nor. pi. 5, fig. 13. 



