408 PROCEEDINGS OF THE ACADEMY OF [April. 



The shells at these places are so perfectly preserved that even the term 

 "semi-fossil" seems a misnomer for them. Probably the sand pre- 

 serves them by saturating the water with lime before it reaches them. 



One of these shell deposits, locality No. 818, on the land of Mr. Benja- 

 min Trott, in Tucker's Town, is only from 8 to 36 inches below the 

 siu-face. The P. nelsoni were mostly in the upper foot of the deposit, 

 where the bank is thoroughly solidified by the rain ; but a few inches 

 lower the sand is still loose enough to be scraped out with a strong hoe. 



The two localities last to be mentioned, Nos. 808 and 809, are essen- 

 tially ahke. They face the Devonshire marshes on the northwest 

 side — 808 near the north end and 809 close to the barracks. The sand 

 in these dunes appears to have drifted from near the present line of 

 the north shore — a consideration which may yet give a clue to their 

 age. 



The following are my records of fossil and semi-fossil shells in these 

 localities : 



Locality 807. 



PCECILOZOXITES NELSONI, 



" NELSONI CALLOSUS. 



" CIECUMFIRMATUS, | -r , 



,, r Intergraded. 



DISCREPANS. ' * 



EUCONULUS TURBINATUS. 

 ZONITOIDES ^nXUSCULUS. 



" BRiSTOLi, One specimen. 



Thysanophora hypolepta. 



SUCCINEA BERMUDENSIS. 



Vertigo numellata. 



" MARKI? 



Carychium BERMUDENSE. 



Casts in the Rock, Locality 806. 



Pcecilozonites circumfirmatus. 



Vertigo. > 



Carychium? 



Cave and Pockets, Locality 806. 

 Pcecilozonites nelsoni. Both extremes in height of spire. 



" BERMUDENSIS ZONATUS. 



" REINIANUS. 



" CIRCUMFIRMATUS. 



