... beaks ; cardinal margin sloping very convexly towards the posterior end, which is subtruncated. Surface marked by small lamelliform ribs, separated by spaces about equal to four times the thickness of the ribs themselves ; the interspaces are sometimes... Palæontology - Seite 1651864 - 299 SeitenVollansicht
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...the ribs themselves ; the interspaces are sometimes plain, sometimes striated. Inner margin plain. Localities : Abundant near Fort Tejon, whence it was...by Mr. Conrad, that has been found in California." It appears that Gabb was mistaken concerning "the only species with the peculiar surface ornamentation,"...