﻿BIVALVIA. 



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Cardita borealis ? Conrad. Crag Moll., vol. ii, p. 168, Tab. XV, fig. 6 (as C. 



analis ?). 



Cardita borealts, Conrad. Amer. Mar. Conch., 39, pi. viii, fig. 1. 



Locality. Chillesford bed, Sudbourn Walks ? Upper Glacial, Bridlington. 



This shell, which was described by me under the name analis^ I know from Bridlington 

 only, but Mr. Bell ('Mag. Nat. Hist.' for 1870) gives it from the Chillesford bed of 

 Sudbourn Church Walks, though I have not seen the specimen. In the ' List of Shells 

 from the Norwich Crag,' by the late Dr. Woodward, the Bridlington shell was referred to 

 Cardita borealis, Conrad. The specimens from Bridlington in the British Museum (about 

 twenty-five in number) are much smaller, not measuring more than half an inch in diameter, 

 while the American shell reaches at least an inch, and appears to have a more excentric 

 inclination of the umbo ; but, according to Gould, in the young shell the beaks are more 

 central, so that this difference may be due to the Bridlington specimens being all young ones. 

 A shell from Labrador, that seems to be fossil, or semifossil, shown to me by Mr. A. Bell, 

 resembles the Bridlington shell ; while a recent specimen of borealis from Gaspe, also 

 shown to me by Mr. Bell, appeared to be different from the Bridlington form in being 

 much more transverse. Under these circumstances I have referred the Bridlington shell 

 to the American living species with a doubt, as I am not altogether satisfied on the point. 



Cardita scalaris, Leathes. Crag Moll., vol. ii, p. 1G6, Tab. XV, fig. 5. 



Localities. Cor. Crag passim. Red Crag, Sutton and Walton. Fluvio-marine 

 Crag, Norwich? Chillesford bed, Chillesford? Middle Glacial, Hopton. Living, 

 North-West America ? 



This species is exceedingly abundant in the Cor. Crag, and it is not rare in the Red 

 Crag of Suffolk, but many of these latter may be derivatives from the Cor. Crag. One small 

 valve, not quite perfect, was obtained by Mr. Dowson from the Middle Glacial Sands of 

 Hopton and sent to me, and it is given by Dr. Woodward in his Norwich Crag List in 

 White's ' Directory ' as from Norwich and Chillesford, but as I have not seen any 

 specimens from either of these places, I have given those localities with a note of interro- 

 gation. The species seems to me to survive on the North-West Coast of America, as a 

 shell from there in the British Museum under the name Cardita ventricosa, Gould, 

 appears to me to be identical with the Crag form. This species is given as a 

 Bridlington fossil by E. "Forbes, 'Mem. Geol. Surv.,' p. 415, 1846, but I have not seen 

 the specimen, and believe it to have been confounded with borealis {analis). I have not 

 met with it from any of the localities of the Chillesford bed or from the Lower Glacial 

 Sands. 



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