BIVALVIA. 137 
AsTARTE BOREALIS, Chem. Crag Moll., vol. ii, p. 175, Tab. XVI, fig. 3 a, 4. 
Localities. Fluvio-marine Crag, Bramerton, Thorpe, and Postwick. Chillesford 
bed, Aldeby, Bramerton, Horstead, and Coltishall. Lower Glacial, Weybourn, Belaugh, 
and Rackheath. Middle Glacial, Hopton. Upper Glacial, Bridlington. Post Glacial, 
March. 
This is one of the very few shells of the Fluvio-marine Crag, that on the assumption 
of their being coeval deposits, might have been expected to occur also in the Red, but 
which have not yet been found init. Although present in the Fluvio-marine Crag at 
Bramerton, I am informed that it is rare, while in the Chillesford bed exposed in the 
same deep section at Bramerton it is common. It occurs in the Chillesford bed at most 
of the localities except at Chillesford, at which place I have not heard of its occurrence ; 
and it has been found in the Lower Glacial Sands at Belaugh, Rackheath, and Weybourn, 
the base of those sands at the first of these places being literally a pavement of detached 
valves of this shell. It is not uncommon at Hopton in a fragmentary state, but only one 
perfect valve has occurred there. The specimens from March are somewhat peculiar, 
having fine striations, so that it was inserted by Mr. Secley in his list of shells in the 
‘Quart. Journ. Geol. Soc.,’ vol. 22, p. 473, as 4. crebricostata. The March specimens, 
however, have not the denticulated margin of crebricostata, and some of the specimens 
exceed in magnitude any of creéricostata thet I have seen. The form called Withami 
(fig. 8 c—d) appears to be confined to the Bridlington locality, where it occurs in 
association with the typical form of 4Joreadis, and, so far as shape is concerned, seems to 
bear the same relation to it that 4. e/liptica bears to A. sulcata; but there is not the 
difference of a notched margin such as obtains between ed/ptica and sulcata. 
Astarte Burtinit, La Tonk. Crag Moll., vol. ii, p. 188, Tab. XVII, fig. 5 a—d. 
Localities. Cor. Crag passim. Red Crag, Sutton. Fluvio-marine Crag, Bramerton ? 
Middle Glacial, Hopton. 
This shell still remains to me very rare in the Red Crag. It is given by Dr. 
Woodward in his list in ‘ White’s Directory ’ as in the Norwich Crag, on the authority of 
a single valve said to have been found there by Mr. Wigham; but I have not been able 
to hear of its occurrence there from other sources, and its presence in the Fluvio-marine 
Crag must be received with doubt. I have not met with it from the Lower Glacial 
sand or from any of the localities of the Chillesford bed. In the Middle Glacial sands 
of Hopton several young specimens have occured, but all, except one of them, imperfect. 
I have not met with it from any newer Glacial or from any Post Glacial bed, nor do 
I know it as living. 
