100 SUPPLEMENT TO GREAT OOLITE MOLLUSCA. 



anfractu ultimo ct penultimo in media anyulato, costis subnodulosis cingendis, angulo tuber- 

 culis regularibus depressis coronatis ; basi striis concentricis el radiantibus decussatis, 

 umbilico patens, angulato, concentrice striato ; apertura depressa, sublunulata. 



Shell turbinated ; spire elevated, its apex obtuse ; volutions (5), of which the first 

 three are rounded and without ornamentation, the two latter enlarge rapidly, are angulated 

 in their middle, and coronated with a row of regular depressed encircling tubercles, above 

 and beneath the angle are also three or four rows of nodulous encircling costae, of which 

 those beneath the angle are the most prominent ; the base is slightly convex, concentri- 

 cally and radiately striated; there is an open umbilicus encircled by an angle, and 

 concentrically striated ; the aperture is depressed and sublunulate. 



The last volution has the surface above the angle much flattened, and rendered rugose 

 by the nodulous elevations ; the encircling costae are closely arranged, somewhat irregular, 

 and become smaller towards the base of the last volution. In the specimen figured the 

 outer lip is imperfect. 



Geological Positions and Localities. The Forest Marble of Laycock and Pound Pill ; 

 in the collection of W. Walton, Esq. 



TURBO BURTONENSIS, Lye. Tab. XLV, fig. 15. 



Testa turbinata, spira elevata, anfractibus (4) convexis, cingillis tuberculosis tribus 

 magnis instructis ; ultimo anfractu basi cingillis (3 aut 4) ; apertura ovata, umbilico nullo. 



Shell turbinated ; spire elevated ; volutions (4) convex, each encircled by three rows 

 of closely arranged large tubercles ; the last volution has at the base three or four con- 

 centric rows of smaller tubercles ; the aperture is ovate ; there is no umbilicus. 



The upper part of each volution is somewhat flattened, upon which is one row of 

 tubercles, the other two rows are more closely arranged j the tubercles are large and 

 obtusely rounded. The basal transverse diameter is one fourth greater than the height. 

 It is allied to Turbo muricatus, Sow., but with a shorter spire, more constricted sutures, 

 and the tubercles much larger. 



Geological Position and Locality. The Forest Marble of Burton Bradstock ; in the 

 collection of W. Walton, Esq. 



TURBO SUBTEXATUS, Lye. Tab. XLI, figs. 15, 15 a. 



Testa parva, in/la/a, spira elevata, anfractibus valde convexis, postice subhorizontalibus, 

 antice convexis, suturis profunde impressis, anfractu ultimo permagno, apertura ovali, 

 umbilico nullo ; superficie lineis concentricis et longitudinalibus tenuisssimis, aut punctis vix 

 notatis. 



