On the so-called " Gault " in Norfolk. 57 



though the shells themselves are usually coated internally with a 

 smooth-grained black phosphate. Unfortunately, in so coarse a bed 

 there is not much chance of finding the contemporaneous fauna 

 preserved, and as nearly all the collecting has been done after the 

 material has been roughly washed by machinery, any con- 

 temporaneous shells have probably been entirely destined. 

 Collecting small fossils before the bed is washed is also very difficult, 

 for it is impossible to see any, and the phosphate bed is not left to 

 the action of the rain, but is immediately carted away. 



Leaving, therefore, the Phosphate Bed, which, though strati - 

 graphically merely the basement-bed of the overlying Marl, cannot 

 yet be proved to be so by evidence of the fossils, the undoubtedly 

 contemporaneous shells of the underlying 3 or 4 feet of Marl (No. 4 

 of the section) were carefully collected and examined. The result 

 showed, that while at first sight there was abundance of evidence for 

 the correlation of the Marl with the Gault, yet closer examination 

 proved the Gault fossils to be derived, and the contemporaneous 

 fauna to belong to the Chalk Marl. 



The following is a complete list of the fossils obtained in the Marl 

 at West Dereham Coprolite Works — nearly all of them were found 

 within two feet of the Coprolite Bed : — 



Peniacrinus, sp. 

 Pseudodiadema, spine. 



Serpula, sp. 



Terebratula biplicata, Sow. 

 Bhynchonella, sp. 



A.nomia, sp. 



Exogyra haliotoidea, Sow. 



Ostrea acntiro&tris, Nilss. 



vesicularis, Lam. 



Plicatula, sp. 



Pecten orbicularis, Sow. 



quinquecostatus, Sow. 



Nacula pectinata, Sow. (cast) . 

 Pholadidcsa ? in wood. 



Dentaliurn ellipticitm, Sow. (casts). 

 Ammonites interruptus, Briig. (casts). 



Belemnites attenuatus, Sow. 



minimus ? List. 



ultimus, D'Orb. 



Samites, sp. (cast). 



Beryx, sp. (in light-coloured phos- 

 phate). 



Cymolichthys ? (Saurocephalus) 

 striatus, Kg. 



Odontaspis gracilis, P. & C. 



Py modus, sp. 



Inoceramus, sp. 

 Lima, sp. 



Of these the most conspicuous and easily found, except the Belem- 

 nites, is Ammonites interruptus, which is a characteristic Gault form. 

 But this species, and also Hamites, Dentaliurn ellipticum, Nucula 

 pectinata, Pholadidaia, and the fish are all phosphatized, and usually 

 rolled. They are probably derived from the Gault. The rest are 

 white and unphosphatized, and are all known from the Lower Chalk 

 of other districts. Two, Ostrea vesicularis and 0. acutirostris, have 

 not been discovered below the Chalk. 



Around West Dereham numerous trial-holes have lately been 

 made to prove the Coprolite Bed, and most of these were still open 

 while the Survey was in progress. Unfortunately, none of them 

 show more than from two to four feet of the overlying Marl, nor do 

 the old works appear to have exposed any deeper section. Every- 

 where Belemnites attenuatus, B. ultimus, and B. minimus ?, are abundant, 

 and associated with them is often found the phosphatized Ammonites 

 interruptus. 



