part 1] &AULT A^B LOWER GEEENSAND NEAE LEIGHTOlSr. 49 



Poplars pit (fig. 14, p, 23). It is to be remembered, however, that, 

 except under Shenley Hill, the breccia is never far below the 

 present sm-face, and generally shows signs of recent weathering, 

 as well as of an older alteration before the deposition of the Gault, 

 so that calcareous fossils other than those embedded in the solid 

 limestone-lenticles or in phosphatic nodules have had a poor chance 

 of survival, even if originally present. 



The thick wedge of greensand which intervened between the 

 Gault and the breccia in former workings at Garside's pit, 

 Shenley Hill, first exposed after our former paper was published (as 

 described on pp. 10-13, fig. 4), was better provided with organic 

 remains. It proved, however, a disappointing collecting-ground, 

 owing to the patchiness of the fossils and their poor condition, 

 aragonite shells (as in the limestone) occurring only as casts, and 

 those of calcite beino: scalv and friable. 



The better part of my collection of these fossils is at the Jermyn Street 

 Museum ; the remainder, along- with a few collected by Walker, are still in 

 my possession ; the following rough list includes the material in both sets. 



' Belemnites minimus ' and ' var, attenuatus ' (the most abundant fossil) ; 

 cast of a larg-e Na^itihis, resembling ' N. radiatus ' ^ ; indeterminable fragment 

 of a cast of ? ammonite ; ' Inoceramus concentricus ' (several casts, more or less 

 crushed, chiefly of the broad coarsely-ribbed variety found in the overlying 

 Gault, see p. 51) ; ' Anomia ' ; several small oysters, among which Dr. Kitchin 

 & Mr. Pringle recognize (K.P., p. 6) ' well- developed valves of Ostrea vesi- 

 cularis Lamarck, and 0. canalicnlata (J. Sowerby) ' ; ' Terebratula,' some 

 crushed, others in waterworn fragments, rather numerous, but the only 

 one found identifiable by Walker was the specimen of Terebratula ohtusa 

 Sowerby mentioned previously (p. 45) ; many fragments of ' Serpula,' among 

 which Serpula antiquata J. de C. Sowerby has been recognized (K. P., 

 p. 6) ; several detached valves of cirripedes, believed to be mostly referable 

 to Pollicipes glaher P. A. Eoemer and Pycnolepas rigidus (J. de C. Sowerby) 

 (see K.P., p. 6); two small echinoderm-tests in very poor condition, sub- 

 mitted to Prof. H. L. Hawkins, and reported to be probably ' Cardiaster ' 

 or ' Holaster,' but beyond specific recognition. There are also two or three 

 indeterminable casts of gastropods. 



Among the half-dozen small but fairly well-preserved fish-teeth, Mr. E. T. 

 Newton has recognized Lamna appendiciilata Agassiz. Scaphanorhynclnis 

 suhulaUis Agsissiz, Sc. rapModon (?) Agassiz, and Apaleoduts (?J. The three 

 species named are recorded as occurring in the Mammillatus-beds of France, 

 as well as in higher zones of the Gault.^ 



Fossils of the Gritty Phosphatic Nodules (Mammillatus- 



bed). 



This fauna, discovered since the publication of our former paper, 

 is probably the best development of the Mammillatus-fauna known 

 in this country, but will require much specialized work, as well as 

 further collecting, before it can be adequately discussed. It was 

 briefly referred to in my report of the Geologists' Association 



^ Approximate determination by Mr. E. T. Newton, F.R.S. 



^ A. J. Jukes-Browne, ' Gault & Upper Greensand,' Mem. Geol. Surv. supra 

 cit. p. 379 ; and C. Jacob, ' Etudes Paleontologiques & Stratigraphiques sur la 

 Partie Moyenne des Terrains Cretaces dans les Alpes Pran9aises, &c.' Trav. 

 Lab. Geol. Grenoble, vol. viii (1907) p. 311. 



Q. J. G. S. No. 309. E 



