200 Mr. R. B. Newton on Fossil Mollusca &c. 



Barnea, which includes shells anteriorly closed and possessing 

 a single dorsal accessory plate or umbonal shield. It differs, 

 however, from that species in the umbo being rather further 

 removed from the anterior margin and in its more regularly 

 spaced costse, the last one of which forms a prominent oblique 

 demarcation between tiie anterior and posterior surfaces ; the 

 posterior region is likewise relatively larger than in the 

 recent shell. The specimens have none of the delicate shell- 

 structure remaining, although as casts all the details of 

 sculpture are well preserved. There is, moreover, no indica- 

 tion of the umbonal shield. 



Examples of this shell are of frequent occurrence in these 

 deposits. 



Sc APH PO I) A. 



Dentalium entale, Linnaeus. (PI. VI. fig. 14.) 



Dentaltum entalis, Linnaeus, Syst. Naturae, 1758, ed. x. p. 785; Forbes 

 & Hanley, Hist. British Mollusca, 1849, vol. ii. pi. Ivii. fig. 11, 

 p. 449 ; Hoenies, Foss. Moll. Tert. Beck. Wien, Abhandl. k.-k. 

 Geol. Eeichs. 1856, vol. iii. pi. 1. fig. 38, p. 658. 



Remarks. — This specimen is fragmentary and badly 

 preserved, yet sliowing a fairly complete axial contour. It is 

 a rounded form, with a gentle curvature, and apparently 

 tubular throughout. There are no indications of longitudinal 

 striations, the form appearing to be quite smooth, with the 

 exception of concentric growth-lines, which are most apparent 

 at the anterior or widest end. It is without fissure or labial 

 ])rojection at the posterior end. 



JJimensions. — Length 42, diameter (anterior) 6 mm. 



The fossil appears to differ in none of its details from tiie 

 living f^pecies of the Mediterranean, and it curiously corre- 

 sponds in size and curvature with the figure of Forbes and 

 IJanley of a specimen found off the British coasts. Tlie 

 spt'cies a})pears to have existed from Miocene times upwards, 

 having been recorded from the Upper Teitiaries of Europe. 



Gastropoda. 



There are fragmentary remains of Gastropoda distributed 

 through these sandy constituted deposits, but they do not 

 lend themselves to determination, and nothing further can 

 be said of them ; but they include a possible Turritella and 

 some fusoid shells (see PI. VI. fig. 15). 



