106 



IT. KEEPING AND E. B. TAWNEY ON THE BEDS AT 



List of Shells {continued). 



*Ancillaria buccinoides {Lam.) 0, H. 



*Natica Studeri (JBronn) C,H. 



* labellata (Lam.) 0, H. 



Cancellaria muricata ( Wood) 0, H. 



elongata (M/st) C, H. 



Odostomia gracilis (Ed. M S.) 0. 



Scalaria tessellata (Ed. MS.)... C. 



*Cerithium variabile (Desk.) ... C, H. 



* pseudocinctum (d'Orb.) C, H. 



duplex (Sow.) H. 



ventricosum (Sow.) 0, H. 



varians (Ed. MS.) C, H. 



(Vicarya) coucavum 



(Sow.) C,H. 



Melania fasciata (Sow.).... C, H. 



muricata (Sow.) 0, H. 



Hydrobiabulinioides^. MS.) C, H. 

 Melanopsis subfusiformis 



(Morr.) . C,H. 



fusiformis (Sow.) C, H. 



Actaeon dactylinus (Ed. MS.) . 0. 



Neinatura parvula (Desk.) ... C, H. 



Merita aperta (Sow.) ,„ ; C, H. 



zonula ( Wood) 0, H. 



Neritina concava (Sow.) C, H. 



Bulla festuarina (Ed. MS.) ... C, H. 



Lminasa longiscata (Sow.) C, H. 



Planorbis euompbalus (Sow.) C, H. 



obtusus (Sow.) C,H. 



Paludina lenta (Sow.) C, H. 



Ostrea velata ( Wood) C, H. 



*Mytilus affinis (Sow.) C, H. 



*Trigoiiccelia deltoidea (Lam.) , C, H. 



Leda propinqua ( Wood) ...... 0, H. 



Nucula lieadonensis (Forbes) C. H. 



— — nudata ( Wood) 0, H. 



Lucina (Strigilla) colvellensis 



(Ed. MS.)..... 0,H. 



Cytberea suborbicularis 



(Ed. MS.) 0, H. 



* incrassata (Sow.) C, H. 



Tellina lieadonensis (Ed. MS.) C, H. 

 [*]Psammobia compressa (Sow.), 



var. asstuarina (Ed. MS.)... C, H. 



rudis (Lam.) ... 0, EL 



Mactra fastigiata (Ed. MS.)... C,H. 

 *Mya angustata (Sow.) =-pro- 



ducta (Ed. MS.) C, H. 



*Corbula cuspidata (Sow.) 0, H. 



Corbicula obovata (Sow.) C, H. 



Cyrena cj r cladiformis (JDesh.). 0, H. 

 *Balanus unguiformis (Sow.). 0, H. 



Oallianassa Baylii (Woodw.). C,H. 



Faunas of Middle Ueadon from Colwell Bay and Headon Hill 

 compared. 



The above list contains only the commoner forms, such as may be 

 found in a few days' search. Out of a total of 58 species it will be 

 observed that all but 7 were found by us in both localities *, and all 

 but three are known to be common, or, again, a proportion of 94 per 

 cent, of commoner Colwell-Eay forms occur at Headon Hill f. Surely 

 from this we may presume a very close affinity if not identity of 

 these beds. It is stated (op. cit. p. 150) that less than one half of 

 the Headon-Hill and Hordwell species occur at Colwell Bay — a 

 result, it seems to us, only obtained by mixing up fossils from 

 Brockenhurst and "Whiteclrff Bay in the same list with the Colwell 

 forms. We shall show below that the fossils cited from these two 

 latter localities belong to a lower zone. 



Next as to the statement that at Colwell Bay "the strata are of 

 purely marine origin " while " the so-called Middle Marine beds of 

 Headon Hill and Hordwell Cliff are of totally different character " 



* Some of these do not exist from botli localities in the Edwards collection, 

 and have not found their way into the Headon-Hill and Hordwell list in the 

 paper referred to, though previously cited by Dr. Wright from Hordwell 

 (ib. p. 124). 



t Comparing the whole known fauna from the Middle.Headbn of Colwell Bay 

 and Headon Hill, we obtain the following result, viz. 74 per cent, of the 

 Colwell-Bay marine forms have been found at Headon Hill. This is counting 

 as separate species many names in the Edwards collection which are founded on 

 imperfect and single specimens. As we have said, we think a surer guide in 

 comparing faunas is to take only the characteristic and less rare species. 



