MR ROBERT MACLAURIN's LIST OF SHELLS. 241 



glass of son-water, its favourite position was near tho surface at the edge, 

 round which it crawled, with the shell reversed, smd the foot fixed ob- 

 liquely to the plass, partly supported l>y the pollicle of jelly it had ex- 

 rivted". Tho syphon is projected forwards, tho tentacula expanded, and 

 the shell covered with the cloak which, when thus expanded, seems im- 

 sed with stria? like the shell itself. It sometimes left the water alto- 

 gether, and seemed nowise incommoded by the change. 



The immature shell (Cyprcpa bullata, Mont Test. Brit. 202. tab. C. fig. 1.) is 

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

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

 volute. Tho animal differs from the adult merely in tho less evolution 

 of tho cloak. 



of Bivalved Shells found in Coldingham Day. By Mr ROBERT 

 MACLAURIN. 



Fam. OSTRACEA. 



Anomia ephippium. Anomia undulata. 

 squamula. 



Fam. PECTENTD^. 

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



. opcrcularis (not common) obsolctus (very common) 



lincatus (rare) Lima fragilis (rare) 



Fam. ARCACEA. 



Area fusca (very rare) Nucula margaritacea (commfff 

 Pectunculus pilosus (not rare) minuta (not common) 



Fam. MYTILACEA. 

 Mytilus edulis (very common) Modiolus vulgaris (common) 



var. incurvatus (rare) discors (common) 



var. pellucidus (common) discrepans (rare) 



Fara. CONCHACEA. 



Cardium ciliare (not common) Kellia suborbicularis (cox, 

 echinatum (common) Crassina Danmonia (common) 



laevigatum (noJ common) Scotica (common) 



odule (not common) sulcata (rare) 



Donax trunculus (very rare) Cytherea exolcta (very common) 



nova species \ (very rare) Cytheretineta (common) 



Tellina teriuis (common) ovata (rare) 



solidula (common) Venus cassina (rare) 



crassa (very common) fasciata (common) 



Araphidesma comprcssa (not com.) gallina (very common) 



Cryptodon flexuosus (very rare) virginea (not common) 



Lucina radula (wry common) decussate (not common) 



undata (common) pcrforans (very common) 



Cyprina islandica (common) Corbula striata (common) 



Mactra subtruncata (not common) Lutraria clliptica (very rare) 



el liptica (common) - hyans (irry rare) 



. solida (very common) Mya truncata (rare) 



stultorum (writ r arcnaria (not common) 



