100 SUPPLEMENT TO GREAT OOLITE MOLLUSCA. 
anfractu ultimo et penultimo in medio angulato, costis subnodulosis cingendis, angulo tuber- 
culis regularibus depressis coronatis; basi striis concentricis et 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 costa, 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 coste 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. 
Turso Burronensis, Lyc. ‘Tab. XLV, fig. 15. 
Testa durbinata, spira elevata, anfractibus (4) convevis, 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 ftattened, upon which is one row of 
tubercles, the other two rows are more closely arranged; the tubercles are large and 
obtusely rounded. The basal transverse diameter is one fourth greater than the height. 
It is allied to Zurbo muricatus, Sow., but with a shorter spire, more constricted sutures, 
and the tubercles much larger. 
Geological Position and Locality. he Forest Marble of Burton Bradstock ; in the 
collection of W. Walton, Esq. 
Turso suprexatus, /yc. Tab. XLI, figs. 15, 15 a. 
Testa parva, inflata, spira elevata, anfractibus valde convexis, postice subhorizontalibus, 
antice convexis, suturis profunde impressis, anfractu ultimo permagno, apertura ovali, 
unbilico nullo ; superficie lineis concentricis et longitudinalibus tenuisssimis, aut punctis viv 
notatis. 
