It has the appearance of a hump and is traditionally decorated with spiral lines drawn from the top outwards with the point of a knife, and scalloping on the edge.
22.
The whorls are unusually concave, with a stout prominent keel, crossed by numerous oblong somewhat oblique white tubercles or short plicae, which are rendered more conspicuous by a brown intersecting spiral line.
23.
Within, besides the two spiral lines, there are slight longitudinal striations, and the inner edge of the whorls twines like a staircase round it, but concealed by the overcurve of the columellar lip.
24.
In this species the columellar margin is reflexed and pearly, but the interior of the aperture, with the exception of the internal margin of the outer lip, is opaque white, with green spiral lines.
25.
Half the thickness consists of epidermis, marked throughout with plicate line of growth, crossed by faint impressed spiral lines, and on the whorls is 3 and a half, rapidly increasing, the last much larger, rounded at the periphery and beneath.
26.
"Sturia " produced a robust, laterally compressed, high whorled, involute shell; whorls strongly embracing . the surface is without ribs or constructions but does have sharp spiral lines . the suture is ammonitic, deeply digitate; lobes and saddles narrowly V-shaped overall.
27.
Dall & Bartsch made their distinction on the following basis : " O . tenuisculpta " has the incised spiral lines strong on the early whorls and much finer on the later turns, while " O . clessini " has the incised spiral lines only moderately strong.
28.
Dall & Bartsch made their distinction on the following basis : " O . tenuisculpta " has the incised spiral lines strong on the early whorls and much finer on the later turns, while " O . clessini " has the incised spiral lines only moderately strong.
29.
Schepman gives a somewhat divergent description : the posterior part of the shell is nearly entirely yellowish-white with a green tinge, moreover a few smaller patches of the same colour are dispersed over the anterior part, a few dark spiral lines are more conspicuous on the posterior part.
30.
We find in his paintings spectacular spiral lines and longitudinal strokes which glide through the canvas, outlined by an energetic use of the primary palette, extracting from these colors unthought-of shades and gradations that have become a signature and a characteristic of his bold and powerfully musical style.
