. Bulletins of American paleontology. Oregon Oligocene Turridae: Hickman 57. Text-figure 11. — Comparative anal sinus configuration in species of Acamptogenotia, s. s. and Acamptogcnotia {Austrotoma) from camera lucida tracings of growth lines adjusted to uniform shoulder height. Heavy lines denote posterior and anterior sutures, light line denotes periphery, and dashed line denotes apex of sinus, a. A. intorta (Brocchi) ; b. A. morreni (de Koninck) ; c. A. bonellii (Bellardi) , d. A. tessellata Hickman, n. sp.; e. A. nodulosa Hickman, n. sp.; f. A. (Austratoma) laivsi Powell. Description. — S
. Bulletins of American paleontology. Oregon Oligocene Turridae: Hickman 57. Text-figure 11. — Comparative anal sinus configuration in species of Acamptogenotia, s. s. and Acamptogcnotia {Austrotoma) from camera lucida tracings of growth lines adjusted to uniform shoulder height. Heavy lines denote posterior and anterior sutures, light line denotes periphery, and dashed line denotes apex of sinus, a. A. intorta (Brocchi) ; b. A. morreni (de Koninck) ; c. A. bonellii (Bellardi) , d. A. tessellata Hickman, n. sp.; e. A. nodulosa Hickman, n. sp.; f. A. (Austratoma) laivsi Powell. Description. — Shell of moderate size (up to 23 mm), stout, biconic, with a large body whorl, aperture higher than spire; shoulder slope relatively broad, steep, and concave, inclined to axis of coiling at 33°, covered with fine tessellate sculpture consisting of up to 15 close-spaced fine spiral threads intersected by equally fine and closely spaced growth lines marking successive traces of the broad shallow anal sinus; periphery ornamented by 11 to 13 blunt spines representing the most prominent development of nodulose axials that extend posteriorly with decreasing prominence onto the shoulder slope and anteriorly with decreasing prominence and eventual ob- solescence on the base; base ornamented by 12 to 14 crisp primary spiral threads with fine intercalated secondary threads, crossed by numerous fine growth lines; protoconch missing to badly worn on all material at hand; suture undulose, lacking subsutural fold; anterior canal short, twisted, and fasciolate; parietal lip with thin to moderate inductura, ornament usually resorbed but sometimes faintly visible through indictura in parietal region. Ditnejisions of holotype. — Height (incomplete) mm; maxi- mum diameter Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the o
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