152 SERPULA. CHEEPER. 



laterally, sometimes turning on one another with the aper- 

 ture pointing upwards, and sometimes the volutions are 

 not joined together : diameter half a line. 

 On Sertularise. v. v. 



9. Serpula cornea. Linn. Trans, v. pi. 1. f. 33 to 35. 

 Shell brownish horn-color, transparent, rounded, with 



three volutions : minute, 

 An obscure species. 



B. Attached, and irregularly twisted, 10 to 15. 



10. Serpula vermicularis. Twining Creeper. 

 Pennant, pi. 94. f. 3 Da Costa, pi. 2. f. 5 Dorset Cat, 



pi. 22. f. Q. 



Shell white or reddish, opake, quite cylindrical and not; 

 spreading at the base, rugged with transverse wrinkles, 

 gradually tapering to a point, variously curved and entwined 

 in all directions, and attached its whole length. 



Variety A. Much smaller, and more grouped and en^ 

 twined together, of a clear and rather glossy white, and 

 very slightly wrinkled transversely. 



Serpula intricata. Pennant, pi, 94. f. 2, 



Variety B. With a more or less elevated rib along the 

 middle of the back, but differing from S. triquetra in not 

 being in the least spreading at the base. 



Serpula contortuplicata. Linne, Syst. p. 1266. 



Variety C. With the aperture turning in a reversed di* 

 rection. 



Serpula reversa. Montagu, p. 508, no. 11. 

 On shells, crabs, and stones, v. v. 



1 1 . Serpula triquetra. Triangular Creeper. 

 Pennant, pi. 94. f. 3 Da Co sta, pi. 2. f. 9 Donovan, 



pi. 95 Dorset Cat. pi. 22. f. 9. 



Shell white or tinged with red, opake, attached its whole 

 length, with an acute ridge down the back and a little 

 spread on the sides at the base, giving it a triangular ap- 

 pearance, rather rugged with transverse striae, sometimes 

 running nearly straight, but generally coiled and twisted 

 in every direction : aperture round, even and truncate : 



sometimes 



