THE CRETACEOUS SYSTEM 335 



through the whole group, but their presence in any one 

 layer depends upon whether they were strong enough 

 to resist the destructive action of the sea during the 

 formation of that bed, for the coarse sediments contain 

 the strong-shelled species only in recognisable condition, 

 while the fine-grained beds contain both the thick and 

 thin shelled species. 



The following is a complete list of the invertebrate 

 fossils from the Umzamba beds : ] 



Foraminifera 



Haplophragmiwm neocomianum, Chapman. 



,, meridionale, Chapman. 



Bulimina trigonula var. inornata, Chapman. 

 Pleurostomella subnodosa, Reuss. 

 Nodosaria prismatica, Reuss. 



,, zippei, Reuss. 

 Vaginulina humilis, Reuss. 



,, legumen, Linn. 



,, intumescens, Reuss. 

 Cristellaria subalata, Reuss. 

 Polymorphina ? gibba, d'Orbigny. 

 Globigerina canaliculata, Reuss. 

 Truncatulina schloenbachi, Reuss. 

 Pulvinulina elegans, d'Orbigny. 



,, carpenteri, Reuss. 



,, reticulata, Reuss. 



,, pondensis, Chapman. 

 Rotalia soldanii var. nitida, Reuss. 



1 Descriptions and further information will be found in Baily, W. H., 

 Q. J". G. fif., xi., 1855, p.-454. 



Griesbach, C. L., g. J. G. S., xxvii., 1871, p. 53. 



Chapman, F., A. S. A. M., iv., pt. 5, 1904, p. 221. (Foraminifera and 

 Ostracoda.) 



Woods, H., A.S.A. M., iv., pt. 7, 1906, p, 275. (Contains also a descrip- 

 tion of the Polyzoa by W. D. Lang.) 



