^ 



^e 



The first-mentioned rock is a uniform 

 and irregular mosaic of quartz and 

 felspar in approximately-equal propor- 

 tions, and small often acicular flakes of 

 biotite, chlorite, and hornblende, the 

 general appearance recalling a meta- 

 morphosed clastic rock ; the second 

 consists of green hornblende, with a 

 variable amount of biotite and muscovite 

 and water-clear labradorite. Sphene 

 and rutile occur as accessory minerals. 

 The second type of rock appears to be 

 associated quite irregularly with the 

 former. 



(ii) The Calabar River, near 

 the Ekankpa Ford. — -The rocks 

 forming the river -banks recall the 

 banded composite gneiss of Abuton in 

 being a crystalline group, consisting 

 (a) of an acidic gneiss and (6) of fine- 

 grained dark schists. 



The first consists of orthoclase, the 

 phenocrysts occasionally measuring an 

 inch in length, oligoclase, and some 

 quartz, with biotite and muscovite ; the 

 second of quartz, albite, and oligoclase, 

 with small flakes of biotite, and grains 

 of garnet. In some specimens silli- 

 manite is typically developed, and rutile, 

 tourmaline, and zoisite are accessory 

 minerals. Muscovite is often abundant. 



CM 



The following data serve to indicate 

 the directions of foliation throughout 

 the district. The observations are in 

 all cases true, and not magnetic : — 



North-west of Ibam on the \ N. 5° W. to 

 Awai Ikuri path JK 45° W. 



On a tributary of the Calabar 

 River, south of Ibum N. 20° W. 



A second locality south of Ibum N. 11° W. 



North-west of Akwa Ibami N. 22° W. 



South-east of Akwa Ibami 



£ Calabar River, west of Ekankpa 



| North-east of Abong 



3 Kwa River, west of Oban 



t Kwa River at Abuton 



| North of 'Ndengani, near Abuton 



'Nsibimba 



% Path south of A w6f on g 



1 Awdfong 



J Mkpot 



[For the Discussion, see p. 317.] 



>rox. 

 N.45 5 W. 



[approx. 

 N. 27° W. 



N. S. 

 N. 8° E. 

 N. 30° E. 

 N. 28° E. 

 N. 42° E. 

 N. 28° E. 

 N. 25° E. 

 N. 22° E. 



