SERPULA. 1071 



Vermiculum intortum. Montagu Test. p. 520. 

 Plancus, t. 2. f. 1. Gualter, 1. 10. f. S. 



Inhabits sandy shores in all parts of Europe. Red Sea, 

 Gmelln. 



Shell one-tenth of an inch in diameter, white, opake, glabrous, 

 and variable in its formation ; aperture compressed and semi- 

 lunar. Messrs. Maton and Racket express their doubts 

 whether the three species, described by Mr. Montagu under 

 the names of S.subrotunda, S.ohlonga, and S.ovalis, are 

 more than Varieties of this species ; and there are also seve- 

 ral bottle-shaped species, which, on account of their extreme 

 minuteness and doubtful place in the system, 1 have not 

 thought it necessary at present to notice. 



INCURVATA. 3. Shell regular, detached, with three 

 close involutions at the smaller end. 



Serpula incurvata. Adamses Microscope, p. 634. t. 14. f. T. 

 Maton and Racket, in Lin. Trans, viii. p. 246. 



Vermiculum incurvatum. Montagu Test. p. 5 18. 



Walker's Minute Shells, f. 11. 

 Variety/. Vermiculum pervium. Montagu Test. ip. 518. 



Walkers Minute Shells, f. 12. 

 Inhabits the sandy shore at Sandwich. Boi/s. And the Variety 



has been foujid on the Devonshire coast by Mr. Montagu. 

 Shell scarcely one line in diameter, white, and semi-transparent. 



The Variety is rather smaller, and makes only one turn at 



the upper end, which is open or pervious. 



PLANORBis. 4. Shell regular, orbicular, flat, and 

 equal. 



Serpula planorbis. Linnaus St/st. Nat. p. 1264. Gmelin, 

 p. 3740. 



Inhabits the sea on shells. Linnceus. 



No author has noticed this species besides Linnaeus, who says 

 it is very minute, resembling a round scale firmly fixed to 

 other shells, without any external appearance of whirls, but 

 when broken horizontally exhibiting the appearance of a spire 

 in minute concentric circles. 



CEREOLUs. 5. Shell taper, smooth, and sul)-orbi- 

 cular, v/ith many involutions. 



Serpula Cereolus. Gmelin, p. 3745. 



Serpula, No. 12. Schroeter Einl. ii. p. 560. 



Le Pain de Bougie. Favanne, i. p. 665. t. 6. f. D. 



