210 Geological Society. 



With this Atlas before us we are more than ever sure, as we 

 said, that the work will be of immense value, not only to students 

 of the N'ew Zealand Mollusca, but to all malacologists. Would that 

 other governing bodies, including some not far removed from home, 

 could be induced to undertake similar works of scientific utility ! 



PROCEEDINGS OF LEARNED SOCIETIES. 



GEOLOGICAL SOCIETY. 



November 17th, 1915.— Dr. A. Smith Woodward, F.R.S., President, 



in the Chair. 



Mr. John Pabkinsok gave an account (illustrated by specimens 

 and lantern-slides) of some observations on the Structure of 

 the Northern Frontier District and Jubaland Provinces 

 of the East Africa Protectorate, made by him while 

 conducting a water-supply survey for the Government of the 

 Protectorate. A floor of gneisses and schists, among which the 

 Turoka Series of metamorphosed sediments was found at seveml 

 places, is overlain on the western side by lavas, including those 

 arising from the volcanoes Kulal, Assi (' Esie ' of the maps), Hurri, 

 Marsabit, etc., and by probably older lava-fields which together 

 extend as far as long. 39° E. On the south, it was found that 

 the lavas north of Kenya reached the Guaso Nyii'o, leaving 

 ' inselberge ' of the crystalline rocks in their midst, but that a 

 higb gneiss country extended north-westwards from lat. 1° N. 

 and long. 38° E. to within a short distance of Lake Rudolf. 

 Eastwards the Coastal Belt of sediments proved to be of Upper 

 Oxfordian age and to extend to long. 40|° E. (west of Eil Wak), 

 and these were lost southwards under the great alluvial plain of 

 Jubaland. 



At intervals throughout the alluvial plain and lying in hollows 

 in the Jurassic rocks, disconnected exposures were found of soft 

 calcareous sandstones or limestones (Wajhir, Eil Wak), the age of 

 which cannot now be definitely fixed. 



Evidences of the desiccation of the countr}^ were, it was thought, 

 shown (1) by the Laks or water-channels characteristic of Juba- 

 land, which contained surface-water only dm'ing the rainy season 

 and then extremely rarely, if ever, throughout their length ; 

 (2) by the presence of freshwater molluscs in the scarcely con- 

 solidated beds of such Laks and at other places where now no 

 surface-water is present (Buna and near the Abyssinian frontier) ; 

 and (3) by the presence of wells along fault-lines and in other 

 places where, but for the previous presence of springs, it appears 

 improbable that the natives would have begun sinking. 



The region between Lake Rudolf and Marsabit was pointed out 



