zwei makroskopisch verschiedene, ihrer miueralogischen 

 Zusammensetzung nach identische Gesteine beschreibt, und 

 zwar vom Topo da Corva und dem benachbarten Krater 

 des Siderao. 



Aber auch in der Gegend, wo Pohlig Leucitgesteine 

 fand, war schon vor fast 40 Jahren Leucit bemerkt wor- 

 den, nämlich Lof tu s schreibt in der Beschreibung i) seiner 

 Anfang der fünfziger Jahre ausgeführten Reise: 



pag. 300. Section from Beradust, across the Piain of 

 Seimas, to Derik. 



„Gradually ascending in a northerly direction towards 

 the high ränge called Shetkha or Anjulukh Dagh, low cliffs 

 of compact and vesicular basalt, with crystals of leucite, 

 for the first time along the Frontier make their appearance. 

 These are succeded by an elevated piain , in which decom- 

 posing mica schists now and then protrude through the 

 soll; but J could not make out their position with regard 

 to the trap-rocks." 



pag. 301 (dieselbe Lokalität): 



„On the descent to the Chehrik stream the sandstones 

 and gravels of the gypsum - series again make their appe- 

 arance*, dipping at a slight angle to the river and towards 

 the north. Just before gaining the river, a very interesting 

 and remarkable phaenomenon presents itself. The upturned 

 edges of the sands and gravels are overlaid by basalt; . . . 

 The river itself flows between natural cliffs of about 300 

 feet in height, exposing a fine section. 



The basalt, which constitutes one half of the cliff, is 

 in its lower portion highly compact and regularly columnas; 

 but in passing upwards . . . the rock becomes less com- 

 pact, until at the surface it is a highly vesicular basalt. 

 Dispersed throughout are crystals of leucite and other vol- 

 canic minerals." 



Ferner pag. 316. Section from Bayazid to Ardish: 



„A patch of loose white chalk-soil is passed; this 

 further on changes to a bright-yellow volcanic tuff, con- 

 taining much pumice and leucite. 



1) Quart. Journ. of the Geological Society 1855, XI. pag. 247 flf: 

 William Kennet Loftus Esq. Turko - Persian Frontier. 



^g ■; 



^ 

 r. 



