part 8] PLEISTOCENE DEPOSITS AROUND CAMBRIDGE. 227 



1 am indebted to Mrs. Eleanor Reid for permission to ]ml>lis]i 

 this list, and the brief notes byMr. Reid which follow. Mrs. Reid 

 lias added Ranunculus amplexicaulis Linne? to the list. 



.Air. Reid states that: 



* some curious elongate bodies like small cones. I think, are the droppings of 

 ;i lemming. 1 



In discussing the general results of his examination, he remarks: 



; I feel no doubt that your Barnwell bed is contemporaneous with the Late 

 Glacial deposits of the Lea Valley. There is a most striking correspondence 

 in the plant-assemblage, which is not the same as that in the Arctic Bed at 

 Hoxne. or that in the Arctic Bed below the Glacial deposits of the Norfolk 

 roast. Indeed, the resemblance between Barnwell and the Lea Valley is so 

 close as to make me think that a very limited Arctic flora probably occupied 

 i wide area in the Eastern Comities during this period. Not only does the 

 same assemblage occur at each locality, but the same Arctic species are 

 missing (Salix polaris, 8. myrsinites, Dryas, Vaecinium epp. a Arctostaphylos), 

 although these are found at other horizons in Britain.' 



Remains of insects are not uncommon, but it is desirable to 

 obtain more before submitting them to an authority. 



.Miss Gardner and I collected several shells from this exposure. 

 Some came from the peat-seam, others from a loam, belonging to 

 the same set of deposits. Air. A. S. Kcnnard, who kindly identified 

 the shells, tells me that (as would be expected) the fauna is the 

 same in the peat and in the loam. The following were deter- 

 mined by him : — 



Lvmnaea palustris var. diluviana i Planorbis u/nibilicatus (Midler). 



Kunth. Planorbis leucostoma Millet. 



Lim t<;i><i truncatula (Midler). Succi)ie« oblonga Draparnaud. 



Limn&a pereger (Midler). Succinea pfeifferi Kossmassler. 



Hygromia his}>i<l« (Linn,'). j Succinea putris (Linn .'•). 

 Pivpilla muscorum (Linne). Golwmella columella (G.von Martens). 



Pis/, Hum amnicum (Midler). Valvata piscinalis (Midler). 



A list from this pit has already been published by the late 

 Mrs. Mr Kenny Hughes, 1 but shells from more than one deposit 

 seem to have been included; it is, therefore, desirable to publish 

 the above list, for all the deposits exposed at the present time are 



obviously of one age. 



The mammalia recorded by Miss Gardner and myself, as identified 

 by Mr. C. E. Gray from those beds, are the horse, mammoth, woolly 

 rhinoceros, and reindeer: the last-mentioned is fairly abundant. 



It will be seen that plants, mollusca, and mammalia all point to 

 Arctic conditions during the formation of these deposits. 



1 1 1. Conclusions. 



The palaeontological evidence points emphatically to the view 

 that the chronological sequence does not coincide with the relative 

 heights of the deposits above river-level, but that in the lower part 



•of the Cam Valley a period of erosion subsequent to the earlier 



1 Geol. Mag. dec. 3, vol. v (1888) pp. 200 202. 



