230 ORGANIC REMAINS. 



No. 8, M'hich is from the chalk, <liffeis from any species which we 

 have seen described. It is a smooth shell, nearly as long as No. 14, 

 but narrower, and more gibbous. Its chief discriminating character is 

 the marginal line, which, except a slight depression near the beaks, is 

 straight till it reaches the middle of the shell, when it bends upwards 

 into a considerable arch, that reaches to the base. The line of the 

 base, connecting the arch on the one side with that on the other, is 

 nearly straight,^llnd occupies a space equal to half the breadth of the 

 shell. If this shell is not a variety of t. subundata of Sowerby, we 

 might name it anomia arcuata. 



The anomia epJiippium is often found in our strata, adhering to 

 fossil oysters. We may here add, that on a closer examination of 

 the singular shell, figured in PI. VI. No. 14, it is found to corre- 

 spond with the a. producta of Martin, delineated in Parkinson's Org. 

 Rem. III. PI. XIII. Fig. 9, 10. Sowerby makes this shell a new 

 genus, which he names productus ; and it may be noticed, that as we 

 discovered hair-like substances connected with our specimens, several 

 of those which he has figured, Tab. 68, Q9, display minute spines. 



Mactra. Shells resembling the m. stultorum occur in the alumi- 

 nous strata ; and large shells like the m. lutraria, are found both in 

 the oolite, and in the ironstone bands. 



Spondylus. a species approaching to the s. radula of Lamarck, 

 of considerable size, is noticed in the Scarborough Catalogue (p. 108, 

 109), as occurring in the Malton oolite, and in the ironstone beds 

 near Scarborough. We have not had an opportunity of examining it, 



Chama. The beautiful little shell, Fig. 5. PI. IX, has a strong 

 resemblance to the chama calcarata of Lamarck, figured by Parkinson, 

 III. PI, XIV. Fig. 13 ; and if not the same species, must be near 

 akin to it. It is from the ironstone, and retains something of its 

 original colour and pearly lustr«. It is marked with concentric 

 transverse plaits or rings ; and the intermediate spaces are adorned 



