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Triceraspyris pacifica Campbell and Clark, 1944

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Shell of moderate size, distinctly bilobate, divided by a wide, shallow median vertical stricture into two similar, swollen lobes, shell as a whole globular with truncate open, basal plate and with coryphal face with (3?) short, thornlike horns; great-circle thick, prismatic, and hardly distinguishable, save by position, from bars which form framework; pores mostly large, generally circular, some smaller than others, smaller tending to be grouped along sides and median line of hemispheres, about 25 pores on one half shell, pores deeply set, with concave, fairly wide, matlike areas around them, these mats enclosed in a narrow, ridgelike, prismatic, polygonal (subhexagonal) framework which is very clumsy, bars heavy, and from point of union of adjacent bars arise short, , blunt thorns; wall thick; surface rough; feet three, one caudal and two paired pectoral, caudal possibly a little shorter than others, practically equidistant, inwardly bent like large claws, all shorter than shell, each leg terminally pointed and with a winglet or side branch like a blade, also each one with a group of tiny thornlike hooklets about 0.3 of length from proximal end (these the points of attachment of contractile, protoplasmic structures related to dynamic regulation of flotation in living animal); interspaces between legs broad, low arches. Length of legs, 37.4; diameter of shell, 96.8.
Triceraspyris pacifica differs from all species of the subgenus to which it is doubtfully assigned in character of surface which is simply roughened rather than tuberculate, mammilate, or smooth. Indeed, this species is only doubtfully assigned to genus Triceraspyris for it is difficult to make certain of character of coryphal surface and to be positive of presence of horns which at most are only slightly greater than general surface thorns.
Campbell and Clark 1944











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