16 THIRD SUPPLEMENT TO THE CRAG MOLLUSCA. 



[Mr. Robert Bell, who has of late years very assiduously searched the Walton beds, 

 as well as examined several collections made by others from that locality, has kindly 

 furnished the following list of all the molluscan remains which he has been able to 

 detect there, beyond those given in the column for that place in my father's lists in the 

 first Supplement to his work. The species to which an asterisk is affixed are additions 

 to the mollusca of the Upper Tertiaries of the east of England, given in the previous part 

 of this work, and are inserted solely on the authority of Mr. Bell. 



Gasteropoda. 



Erato lasvis, Don. Natica catena, Da Costa. 



Nassa labiosa, J. Sow. clausa, Brod. and Sow. (affinis. of 



propinqua, J. Sow. Gmel.} 

 Buccinum un datum, Linn varians, Dujardin. 

 Trophon consocialis, JS. Wood (one speci- Vermetus intortus, Lam. 



men only, much worn, and Trochus formosus, Forbes. 



probably derivative). multigranus, S. Wood. 



gracilis, Da Costa. Adansoni, Payr. 



scalariformis, Gould. tumidus, Mont. 



Pleurotoma linearis, Mont. Kicksii, Nyst. 



turrifera, Nyst. Montacuti, W. Wood. 



nebula, Mont. zizyphinus, Linn. 



rufa ? Mont. Emarginula crassa, /. Sow. 



Turritella planispira, S. Wood. Tectura virginea, Mull. 



Chemnitzia communis,* ? Risso. (perhaps Dentalium dentalis, Linn. 



only a short form of C. internodula.} rectum, Linn. 



Eulima subulata, Don. Action subulatus, S. Wood. 



Odostomia acuta, Jeff* tornatilis, Linn. 



Bivalvia. 



Mytilus edulis, Linn. Nucula tenuis ? Mont. 



Modiola phaseolina? Phil. Cardita senilis, Lam. 



Nucula nucleus, Linn. Cardium fasciatum, Mom. 



Cobboldise, /. Sow. P 1 Cardium strigilliferum, S. Wooa. 



1 My father collected extensively at Walton at intervals during forty years, and Mr. Robert Bell also 

 very assiduously for many years past, without either of them having met there with the slightest trace of this 

 shell, so common in the later part of the Red Crag ; but Mr. Bell has lately met with a single worn valve 

 in the collection made from Walton by Mr. Greenhill, of Vermont College, Clapton, on the authority of 

 which the shell is inserted with a note of interrogation in the above list. 



