174 NATURAL SCIENCE. Sept., 



In the immediate neighbourhood of Ipswich the Upper Chalk is 

 reached in the lower part of the valleys at several points. It is 

 succeeded by a thin representative of the Thanet Sands, here, un- 

 fortunately, seldom yielding determinable fossils, though casts of 

 Nucula and Cardium are in the Ipswich Museum. Next occur the 

 current-bedded and variable Woolwich and Reading series, consisting 

 here mainly of sands, but with occasional lenticular masses of red- 

 mottled clay. These have yielded no fossils near Ipswich. 



The lower part of the London Clay is well seen at various places, 

 particularly in the sea-cliffs at Felixstowe and Harwich, where it 

 yields remains of turtles, fish, and pyritised plants. An enormous 

 quantity of London Clay fossils is also obtained from the gravelly base 

 of the Crag, but these are principally phosphatised bones and teeth of 

 sharks. It is probable that short excursions during the meeting of 

 the Association will give an opportunity for an examination of all the 

 Eocene deposits represented near Ipswich. 



There is little doubt that, for the majority of visitors, the geological 

 interest centres around the fine series of Pliocene and Pleistocene 

 deposits represented in the Eastern Counties. The succession is 

 apparently more complete than anywhere else in Northern Europe, 

 and we must travel as far as Italy and Sicily before meeting with so 

 continuous a series of strata belonging to these periods, and so large 

 a variety of fossils. 



Between the lowest Pliocene deposits and the London Clay there 

 is a marked break and unconformity, so that the gravelly base of the 

 Pliocene is full, as already stated, of derived Eocene fossils. Of these 

 a good series will be seen in the Ipswich Museum ; and it will be 

 noticed also that mixed with them occur some derivative fossils of 

 very early Pliocene date. True Miocene fossils are apparently 

 missing ; though a few possibly derived from Oligocene beds do occur. 

 This Pliocene basement bed is, or rather was, extensively worked for 

 phosphatic nodules, and though many of the nodules are inorganic, 

 there is so large a mixture of bones and teeth as to make the " nodule 

 bed," miscalled a " coprolite bed," one of the most celebrated horizons 

 in Britain for Tertiary fossils. The fossils consist to a large extent of 

 bones or teeth of whales, dolphins, and sharks ; though mixed with 

 these are many teeth of land animals, such as the mastodon, 

 rhinoceros, tapir, pig, and deer. It is unfortunate that the com- 

 petition of cheaper foreign phosphates has rendered it impossible 

 any longer to work these pits, but a few sections will probably 

 still be visible, though it is difficult now to obtain any mammalian 

 remains. 



The oldest undisturbed Pliocene deposit yet found in the Eastern 

 Counties is a soft limestone composed mainly of shells and bryozoa. 

 This is the so-called Coralline Crag, which has yielded a most 

 prolific Older Pliocene marine fauna, showing affinities with that of 

 the existing Mediterranean and a similar climate. Above the Coral- 



