AIBA-FERRA PASS. 75 



lower series of traps crop out, inclined at a considerable 

 angle, and they are traceable to some height south of the 

 vaUey, the horizontal beds resting quite unconformably 

 upon them. The two series are so similar in general 

 character, that in the hurry of travelling to the front, 

 although I noted the dips, I attributed them to local dis- 

 turbance, and it was only when returning that I clearly 

 distinguished between the two separate groups of beds. 

 Nevertheless the evidence, when examined, was found to 

 be very complete. 



At Aiba I first saw and shot a dwarf goose peculiar 

 to Abyssinia {Bernicla cyanoptera of ElippeU), which I 

 subsequently found abundantly on the higher plateaux, 

 and which appears only to be found at considerable 

 elevations. On the passes around I saw a bunting 

 [Emberiza ccesia) and a serin {Serinus or Criihagra 

 nigriceps) which I had not previously met with. 



I left Aiba on the 1st April, and ascended the long 

 slope leading to the Ferra pass. From the top of the 

 inclined traps, about 300 or 400 feet above the valley, 

 to the crest of the pass, 10,500 feet above the sea, or 

 1,500 above the valley, and again from that to the im- 

 mense amba of Daga, at least 1,500 feet more, the whole 

 mass of the mountain consists of massive horizontal beds 

 of dolerite and trachyte. The latter appears to prevail, 

 especially in the higher part of the pass, and in the amba 

 above, and it is conspicuous by the much more distinct 

 vertical scarps which mark its outcrop. It is pale in 

 colour, very often brecciated, some beds being apparently 

 in great measure composed of volcanic scoria and ash, 



