GASTEROPODA. 135 



margin surrounding the umbilicus, and its elegantly imbricated costse, or reflected lines 

 of growth. The spiral striae are most distinct at the outer part of the base of the shell, 

 but traces of them may be detected on the upper part of the volution between the 

 costge. The aperture of the shell is hidden in the matrix. 



2. Margarita (?) maculata. S. JFoocl. Tab. XV, fig. 3. 



.■jc SoLARiELLA MACULAT.\. S. TVood. Cat. 18-12, p. 531, pi. 5. fig. 7, 10. 

 Turbo moniliferus. Nyst. Rech. Coq. foss. d'Anvers 183.5, p. 27. 

 Solarium tukbinoides. Xi/st. Coq. foss. de Belg. p. 370, pi. 2G, fig. 7, 1844. 

 — Lijel/. In Quart. Journ. Geol. Soc. p. 555, 1845. 



M. Testa troclioided, vel solririformi, tenui et fragili ; spird depressd; anfradibus 

 quinque, Huhcijlindraceis, cremdatis ; cingulis tribiis vel quatuor, ornatis; suturis profundi^ 

 cancdiculatis ; aperturd rotwndatd ; uiiibiUco matjno,granulato. 



Shell depressedly conical, subtrochiform, or rather solariform ; spire slightly 

 elevated ; apex rather obtuse ; volutions four or five, subcylindrical, with three, some- 

 times four, rugose or crenulated bands or ridges, the upper one of which is the most 

 prominent; base rough, striated or ridged, with a large open umbilicus, and a 

 carinated and granulated edge ; shell nacreous. 



Axis, \ of an inch nearly ; diameter, I 



Locality. Cor. Crag, Sutton. 



This shell is given as a Miocene fossil of America by Mr. Lyell. Small specimens 

 and fragments are by no means rare from the Crag ; but a shell of the size figured is 

 very difficult to obtain in a perfect condition, fi-om its extreme fragility. It appears, 

 from the form of the shell, to be intermediate between Solarium and Trochus, probably 

 nearly related to the latter ; and closely resembling Margarita. It has three large and 

 obtuse ridges or carinae upon the upper and outer half of the volution, though only two 

 are visible upon the spire. The upper one is largest, and may be said to be divided into 

 three, which are crenulated or granulated by elevated obtuse Hues of growth, and there 

 are upon the base about half a dozen ridges or elevated concentric lines ; the largest, 

 surrounding the umbilicus, is roughly crenulated, like a Solarium, and the volutions 

 are visible beneath up to the apex. In well-preserved specimens the shell is covered 

 with very fine spiral striae. A deep and broad canal is formed near the suture by the 

 elevation of the large upper keel, and there are the remains of coloured blotches, from 

 which character its name was given. 



Tlie Belgian shell, M. Nyst informs me by letter, is the same as the British fossil ; 

 though the figure in the work of that gentleman is much more elevated than any of my 

 specimens. 



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