MR ROBERT MACLATJRIN^S LIST OF SHELLS 



241 



surface at the edge, round which it crawled, with the shell reversed, and 

 the foot fixed obliquely to the glass, partly supported by the pellicle of 

 jelly it had excreted. The syphon is projected forwards, the tentacula 

 expanded, and the shell covered with the cloak which, when thus expanded, 

 seems impressed with striae like the shell itself. It sometimes left the 

 water altogether, and seemed nowise incommoded by the change. 

 The immature shell (Cypra^a bullata, Ment. Test. Brit. 202, tab. 6, fig. 1) ia 

 milk-white, smooth, thin and pellucid, with a wide aperture effuse at the 

 base, and a small spire projecting at the top, having exactly the form of a 

 volute. The animal differs from the adult merely in the less evolution 

 of the cloak. 



List of Bivalved Shells found in Coldingham Bay. By Mr Eobert 



Maclaurin. 



Fam. OsTRACEA. 

 Anemia ephippium. Anomia undulata. 

 squamula. 



Fam. Pectenid^. 

 Pecten maximus (not commoii) Pecten varius {rather common) 



opercularis {not common) — 



lineatus {rare) Lima fragilis {rare) 



Fam. Arcacea. 



obsoletus {very com,mon) 



Area fusca {very rare) 

 Pectunculus pilosus {not rare) 



Nucula margaritacea (common) 

 miuuta (not common) 



Fam. Mytilacea. 



Mytilus edulis (very common) 

 var. incurvatus (rare) 

 var. pellucidus (common) 



Fam 

 Cardium ciliare (not common) 



echinatum (common) 



lasvigatum (not conmon) 



edule (not common) 



Donax trunculus (very rare) 



nova species ? (very rare) 



Tellina tenuis (co7nmon) 



solidula (common) 



crassa (very common) 



Amphidesma compressa (not com.) 

 Cryptodon flexuosus (very rare) 

 Lucina radula (very common) 



undata (commoji) 



Cyprina islandica (common) 

 Mactra subtruncata (not coimnon) 

 elliptica (common) 



Modiolus vulgaris (common) 



discors (common) 



discrepans (rare) 



CONCHACEA. 



Kellia suborbicularis (common) 

 Crassina Danmonia (common) 



Scotica (common) 



sulcata (rare) 



— solida (very common) 



— stultorum (very rare) 



Cytherea exoleta (very common) 

 Cytherea lincta (convmon) 



ovata (rare) 



Venus cassina (rare) 



fasciata (co^nmon) 



gallina (very common) 



virginea (jiot common) 



decussata (not com7non) 



perforans (very common) 



Corbula striata (common) 

 Lutraria elliptica (very rare) 



hyans (very rare) 



Mya truncata (rare) 



arenaria {not common) 



