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Druppatractus acquilonius Hays, 1970

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Cortical shell, ellipsoidal, usually thick-walled, but showing considerable variation in thickness, pores evenly spaced circular to oval, with raised hexagonal borders, 6-7 across minor axis, short thorn-like projections arising from nodes. In some thick-walled individuals, the distal ends of these projections are connected. Shell bears two polar spines unequal in length, circular in cross section, distally sharpened, weakly three-bladed at base. Medullary shell single, ellipsoidal, composed of loose meshwork, pores large, irregular in shape, supported by 8-10 stout beams, 6-8 approximately in the equatorial plane, two along main axis being internal extensions of polar spines.
Length of major axis cortical shell 164-185, width 132-162, pore diameter 6-21 (usually about 17), thickness 10-29, median 21, length of polar spines 35-79. Length of medullary shell 47-57, width 44-47. Description based on 100 specimens from cores V20-109, 107, and V21-148. Dimensions based on measurements made on 25 individuals from cores V20-109 and V21-148.
Hays 1970











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