. Bulletin of the British Museum (Natural History), Geology. CRETACEOUS ECHINODERMS FROM WILMINGTON 181. Fig. 71 Camera lucida drawings of Hemiaster nasutulus from the Lower Turonian of Wilmington: a, , adapical surface showing fasciole pattern; b, , oral plating. SD = 1-9; N = 3) and its width is 66-76% of its height (mean = 72%; SD = 4-9; N = 3). The base of the periproct lies 60-83% of the test height above the base of the test (60% in the smallest individual, 83% in the largest). PERISTOME. The peristome is roughly D-shaped in outline, with a convex anterior margin and a stra
. Bulletin of the British Museum (Natural History), Geology. CRETACEOUS ECHINODERMS FROM WILMINGTON 181. Fig. 71 Camera lucida drawings of Hemiaster nasutulus from the Lower Turonian of Wilmington: a, , adapical surface showing fasciole pattern; b, , oral plating. SD = 1-9; N = 3) and its width is 66-76% of its height (mean = 72%; SD = 4-9; N = 3). The base of the periproct lies 60-83% of the test height above the base of the test (60% in the smallest individual, 83% in the largest). PERISTOME. The peristome is roughly D-shaped in outline, with a convex anterior margin and a straight or very slightly concave posterior face. The length of the peristome is 9% of the test length in all three specimens, while the width of the peristome is 1-8—1 -9 times its length. The anterior edge of the peristome lies 23-28% of the test length from the anterior border of the test (mean = 26%; SD = 2-5; N = 3). The peristome is surrounded by a prominent rim and groove. TUBERCULATION. There is a prominent peripetalous fasciole. This is ovoid and slightly angular in outline and is composed of densely-packed miliaries some six or seven abreast. The distance from the anterior to the posterior border of the fasciole measures 53-63% of the test length while its width is 70-80% of its length. Dorsal tubercles on either side of the fasciole are very small and closely packed, measuring little more than 01 mm in diameter. Larger tubercles border the shallow adapical sinus within the peripetalous fasciole and these are up to 0-2 mm in diameter. Dorsal tubercles become a little larger and stouter around the anterior ambitus. Tubercles are closely packed on the sternal plates and have areoles that are enlarged towards the posterior. There are no tubercles on the labrum. Tubercles in the lateroventral region are sparse. There is no cluster of tubercles in the subanal region, nor are there any modified ambulacral pores. Remarks. This species was first proposed and briefly described b
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