50 



GDIDE TO LOCALITIES. 



The section, according to Merrill, is as follows : l 



40 



10 



1 



1. Fine dark drifted sand, 



2. Yellow sandy drift ferruginous at the bottom, 



and containing pebbles, 



3. Coarse gray stratified sand, with particles of 



green sand, . 



4. Fine white clayey sand, with ferruginous streaks, 



and very minute particles of green sand, 



5. Fragment bed, .... 



6. Upper shell bed, .... 8 



7. Clayey ferruginous sand, ... 4 



8. Serpula sand, . . . . 13 



9. Lower shell bed, .... 9 



10. Eed sand, with fragments of blue clay, . 1 



11. White sand of varying quality and size, . 4 

 Concealed by turf and beach sand, 24 



Total, .... 90 



According to Scudder, below the bed of white sand (No. 11) 

 occur four feet of coarse gravel and sand, and below that the 

 basal beds of light brown sandy clay. 



In the oyster bed (lower shell bed) the shells commonly lie in 

 their natural position, with both valves together (Desor), but 

 Merrill states that they often lie in all positions, with valves 

 separated. The most abundant species are Ostrea virginiana, 

 Venus mercenaria, Modiola hamatus, Cummingia tellinoides, Area 

 transversa and Urosalpinx cinerea. " The assemblage of species 

 is similar to that now living in the protected bays of southern 

 New England, at a depth of three to five fathoms " (Verrill). 

 The Serpula bed consists mainly of convoluted masses of S. 

 dianthus, which still occurs in abundance on the southern coast 

 of New England, in sheltered bays and harbors. At the bottom, 

 according to Merrill, the bed consists of detached masses of the 

 Serpula, closely packed together ; while at the top the tubes are 

 very much comminuted. 



The earlier observers had found scarcely any other species 

 than Serpula dianthus in the Serpula bed ; but Merrill gives a list 



1 Merrill, loc. cit., p. 11. 



