MYA. 93 



SLOPING GAPER. 

 PL 18. /. 2, 3. 



4. Mya declivis. M. testa ovata, compressiuscula, antict subtruncata, 



cardinis dente crasso. Linn. Trans. 8. p. 36. 

 Shell oval and flattish, somewhat truncated at the anterior end ; hinge 



with a thick tooth. 

 Penn. Brit. Zool. vol. 4. p. 160. Pult. in Hutch. Dorset, p. 27. t. 4. 



f. 6. Mont. Test. Brit. p. 40. (M. pubescens.) 



That the M. pubescens of Montagu is the M. declivis 

 of Pennant, there is but little reason to doubt. The 

 full-grown shell, fig. 2. is strong, and covered, exter- 

 nally, with a rough epidermis, like shagrin. One valve 

 is much deeper, and somewhat larger than the other, 

 so that when the shell is closed, the edges of the valves 

 are not together. The interior of the shell is white ; 

 the muscular depressions near the truncated end are 

 strong, but the lower one is not carried so far within 

 the shell as in the preceding species. The tooth is 

 thick, strong, and divided into two cavities by a sharp 

 denticulation. 



Fig. 3. is a young shell of the same species, very thin 

 and brittle, of an oval shape, and white colour. It is 

 very slightly striated concentrically, and the roughness 

 on the outside is not apparent in small specimens. 

 Shells of this size are not uncommon on the Devonshire 

 coast, but large specimens such as fig. 2. have been 

 procured only of late. It is the full-grown shell that 

 Pennant mentions as frequent about the Hebrides, the 

 fish of which is eaten by the gentry. 



