Hevietvs — A. J. Juices- Browne — Up2i&r Chalk of England. 277 



masses or patches. The Foraminifera are all of species found in the 

 oceanic beds. This might indicate that the deposits were laid down 

 on the ocean border, occupying a position intermediate between the 

 iiruly oceanic deposits and the shore. The fossils frequently show 

 -signs of decay and wear — this is particularly noticeable in the case 

 of Pulvinulina pauperata. A very noticeable difference is that the 

 material of the oceanic beds when washed yield a residue consisting 

 almost entirely of Foraminifera (chiefly Globigerina), while that of 

 the Marbela deposit consists mostly of small pieces of slaty-looking 

 and ferruginous materials, the foraminiferal fauna being much 

 scantier than that of the oceanic beds, and it shows no relation either 

 to that of the Pointapier beds or to that of Sangregrande. 



As the Marbela Mine is in the Nariva Series (see my paper in 

 ■CrEOL. Mag., 1900), this series is possibly newer than the oceanic 

 beds, and was formed during the upheaval of the latter, being 

 partly composed of material derived from the oceanic beds. I admit 

 that this opinion is chiefly conjectural — it is in opposition to that of 

 Messrs. Harrison and Jukes-Browne. The conditions generally of 

 the Marbela deposit would suit a depth of water of 100 fathoms or 

 less, and thus it would appear that the Manjak was deposited or 

 formed on a bottom of that depth. It is easy to conceive that the 

 heavy tropical timber brought down by the rivers might sink to 

 that depth. Moreover, such timber is susceptible of being borne 

 along by currents in the same manner as clastic material generally, 

 and hence we find it in the same region as finely-grained arenaceous 

 and argillaceous deposits derived from the degradation of the 

 continent. This explanation further admits of application to the 

 case of Bai'bados. 



I^ :e "V I IB AAT" S. 



I. — Memoirs of the Geological Survey op the United 

 Kingdom. 

 The Cretaceous Eocks of Britain. Vol. Ill : The Upper Chalk 

 op England. By A. J. Jukes-Browne, with contributions by 

 William Hill. 8vo ; pp. x, 566, plate, illustrations. (London, 

 1904. Price 10s.) 



THE Geological Survey are to be congratulated on completing 

 their Official Report on the Cretaceous Rocks of England, 

 for with the publication of this third and last volume the results 

 of many years' work have been given to the public. It is to 

 be regretted that an account of the Irish and Scottish Cretaceous 

 rocks was not included. This volume deals with the White 

 Chalk alone, and of the White Chalk the upper portion only. 

 The beds dealt with are defined by the authors as ' Upper ' Chalk, 

 and consist of the following zones : — Zone of Holaster planus, of 

 Micraster cor-testiidinariiim, of Micraster cor-angiiinum, of Marsiipites 

 ■testudinarius, of Actinocamax quadratus, of Belemnitella mucronata, 

 and of Ostrea lunata. Since the description of the Chalk Rock by 

 W. Whitaker in 1859, the 'Upper' Chalk of the Survey has 



