Pecten maximus var. larvatus Wood, 1857
WOOD, S. V. 1851-1860. A Monograph of the Crag Mollusca, with descriptipns of shells from the upper Tertiaries of the British Isles. Vol II. Bivalves. Paleontographical Society [Monograph, 1851-1861]. [p. 323, pl. 31, fig. 25]
«PECTEN MAXIMUS. Tab. XXXI, fig. 25.
PECTEN MAXIMUS. S. Wood. Monog. of Crag Moll., ante, p. 22.
A single specimen of the flat valve of a species in this genus has lately been given to me by Mr. Whincopp, who obtained it from Sutton.
Although a considerable amount of variation is exhibited in my large series of specimens of what I have considered as P. maximus from the Coralline Crag, I have not seen anything quite so anomalous as is presented by this Red Crag specimen, and confess to be somewhat perplexed respecting it; still there is something peculiar in the arrangement of the ribs of this shell to warrant the belief that there has been a failure in their number of about one half, perhaps caused by what might be called a duplicature or union of the organs by which they were produced, and that it is nothing more than a monstrous form of the common British species. There are six, or perhaps eight ribs, including tbose irregular ridges at the shoulders, rounded and smooth, probably made so by attrition; between them are some smaller rays, varying from two to five. In the recent shell these intermediate rays are also variable, and, in some specimens, they are very distinct and prominent, both between and upon the ribs, while in others they are entirely absent. In order, therefore, to avoid the introduction of a species upon the slender evidence afforded by this specimen, I have called it P. maximus, var. larvatus.» SEARLES VALENTINE WOOD, 1857
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S. V. Wood, 1851-1860, plate 31.
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