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4. Over the eastern and southern 

 parts of the excavation, a thick- 

 ness of blue silt ranging from 

 1 to 6 feet lies next below the 

 recent tidal deposits, but on the 

 north-western side, the tidal 

 erosion having been somewhat 

 greater, this uppermost silt has 

 been washed away and the tidal 

 deposits rest directly upon the 

 peat-bed no. 5. The silt, like 

 the others to be described, is 

 crowded throughout with the 

 roots and rotten stems of sedges 

 in the position of growth, while 

 at the bottom a few foraminifera 

 (see Appendix, p. 485) give the 

 deposit a slightly estuarine 

 character. 



5. This peat-bed forms one of the 

 most conspicuous bands in the 

 series. It ranges from 1 to 2 

 feet in thickness and persists 

 over the whole of the excavation 

 (and, as I was informed by Mr. 

 Storrie, through the old dock also) 

 except in those parts where the 

 rock-surface rises in one of the 

 shoals referred to. In such cases 

 the peat-bed, slightly rising as it 

 approaches the rock, thins away 

 to a feather-edge, but comes in 

 again at its proper level as the 

 rock-surface falls. It keeps at 

 a fairly constant level of about 

 4 feet below Ordnance-datum. 

 Where fully developed it presents 

 the following details : — 



5 a. Laminated peat with logs 

 (including, according to Mr. 

 Storrie, willow, fir, and oak), 

 passing down into 



5 b. Light-coloured flexible marl, 

 composed of the shells of ostra- 

 coda with much vegetable matter. 



5 c. Shell-marl composed princi- 

 pally of the shells of Limncea, 

 Bythinia, etc., with many ostra- 

 coda and much vegetable matter. 



5 d. Peat with logs of oak, etc. (one 

 measuring 5 feet in length by 



