516 Notices of Memoirs — Local Didurhance of Beds. 



express tlie geological age or liomotaxy of South African beds 

 in terms of the geological chronology of the Northern Hemisphere, 

 but the close correspondence of some of the Vereeniging types with 

 Indian and South American species points to their correlation 

 with the Karharbari beds of the Lower Gondwana system. 

 The occurrence of such types as Sigillaria, Boihrodendron, and 

 PsygmopTiyllum shows a closer correspondence between the South 

 African flora and that of the Northern Hemisphere than occurs 

 in the Indian vegetation. We have evidence of an overlapping 

 or commingling of the northern and southern botanical provinces 

 in South Africa and in South America that is not afforded by the 

 Lower Gondwana floras of India and Australia. 



Glossopteris Broicniana (Brongu.). 

 Under this head may be included, 

 at least for present purposes, 

 G. indica and G. angnstifolia. 



Gangamopteris cyelopteroides 

 (Feist.). 



Splienopteris, sp. 



Neuropterklium validum (Feist.). 



Fsygmophyllum Kidstoni, sp. nov- 

 Sigillari Brardi (Brongn.). 

 Boihrodendron Leslei, sp. uov. 

 Noeggerathiopsis Sislopii (Bunb.). 

 Conites, sp. 

 Cardiocarpus, sp. 

 Fhyllotheca, sp. 

 Schizoneura, sp. 



A detailed account of the above species will be published in 

 a forthcoming volume of the Annals of the South African Museum. 

 The writer is indebted to the officers of the Geological Survey of 

 Cape Colony for the opportunity of examining the collections from 

 which these lists have been compiled. 



VIII. — On the Disturbance of Junction Beds from Differential 

 Shrinkage and similar Local Causes during Consolidation. 

 By G. W. Lamplugh, F.G.S.^ 



UPON returning to the investigation of comparatively undisturbed 

 Mesozoic strata, after having studied distortion structures pro- 

 duced by earth-movement in the older Palseozoic rocks, the author's 

 attention has been frequently arrested by local disturbances of the 

 original bedding which cannot be assigned to the agency of deep- 

 seated earth-movement, but are clearly due to minor stresses arising 

 from some local cause in tracts limited in extent, both horizontally 

 and vertically. 



These disturbances are most noticeable where thin bands of one 

 kind of material are imbedded in thick deposits of another kind, 

 and along the junctions where thick masses of different lithological 

 character occur in stratigraphical sequence. 



Examples of the first-mentioned condition are abundant in the 

 Hastings beds of the Wealden formation, where thin layers of clay 

 or shale interbedded with thick sands and sandstones are often dis- 

 rupted into irregular patches and partly mixed with the inclosing 

 sands. The second condition is frequently illustrated in junctions 

 of the Lower Greensand with underlying clays, where strips have 

 been torn from the irregular surface of the clay and dragged up 



^ Abstract of paper read before the British Association, Southpoit, Section C 

 (Geology), September, 1903. 



