WORMS. TBSTACEA 65. Serpula. 201 



SheU not more than the thirty-sixth of an inch in diameter, 

 iranfverfely wrinkled, with fome times a slight ridge along the 

 back. 



Oil. S. spirorbis. White, opake, regular, orbicular : 

 whorli slightly channelled above inwardly, gradually 

 decreasing. 



tr. Zeol. t gi.f. 155. Doucv. t. g. D* Costa t. 2./. ti. 



Skell the eighth of an inch wide, fmooth or slightly Wrinkled, 

 rounded above, flattish underneath, umbilicate in the middle. 



fl!2. . S. granulata. White, opake, clustered, round, with 

 3 elevated ribs on the upper side. 



Donovan Brit. She Us. tab. 100. 



Shell about the size of the latt, fpiral but not quite regular, 

 slightly umbilicate, with two whorls. 



61 3. S. heterostropha. Dirty-white, round : whorls with 

 3 ribs, turning in a contrary direction. 



Montague Brit. Shells f. 503 8. 7. 



Shell refembling the last, but is about half the size, with lefs 

 eminent ribs, and the whorls are placed in a contrary direction : 

 aperture orbicular. 



G14. S. carinata. White, opake, regular : the outer 

 whorl with a reticulate ridge at top. 



Montague Br. Shells p. 502. n. 4. 



Shell about half the size of S. fpirorbii, concave and fometimes 

 pervious ia the middle, a little fpreading at the bafe. 



615. S. corrugate. White, regular, rough with trans- 

 verse wrinkles, umbilicate. 



Montague Brit. Shells p. 503. . 5. 



Shell about the eighth of an inch wide, differing from S. Spirit* 

 lam in being itrongcr, and not exposing fo much of the inner 

 whorls, 



616. &, cornea, Uoru-colour, pellucid, regular, rounded, 

 with 3 whorls. 



Adams Linn. Trans. 5. t. \.f. 33-35- 



<H7. S. lucida. Round, quite smooth, pellucid, glossy, 

 vitreous, with the whorls turning in a contrary 

 direction. 



Adams linn. Trans. 5. t. \.f. 31. 32. 



Shell half a line in diameter, with the whorls fometimes uncon- 

 nected : aperture often projecting upwards. 



618. S. reversa. White, suhcylindrical, rugged, spirally 

 or irregularly twisted : aperture turning in a reversed 

 direction, 



Mentagve Brit. Shells p. 508, n. n. 



Sfittl the tenth of an inch wide, tranfverfcly wrinkled, fome- 

 times pretty regularly fpiral, fometimes variously twisted, with 

 the aperture always reverfed. Probably only a variety of S. ver- 

 micularis, for the inhabitant is the fame. 



B. Contorted, irregular. 



619. S. vermicitlaris. White, cylindrical, tapering, rug- 

 ged, variously curved and twisted. 



Br. Zool. t. 91. /. 1.58. Da Castap. 18. tab. $.f. 2. 



Shfll frm the size of a large thread to that of a Swan's quill, fre- 

 quently clustered, totally affixed to some other fubstance, never 

 carinate along the tuck, .nkibttant with branched fringed tcnta- 



