128 NOTES OF A BOTANIST CHAP. 



visible, and audible only when swollen by rains. 

 Beyond the Bombonasa stretched the same sort 

 of boldly undulating plain I had remarked from 

 Andoas upwards, till reaching one long low ridge, 

 perhaps a little higher than Puca-yacu, of remark- 

 ably equable height and direction (north to south) ; 

 this is the water-shed between the Bombonasa and 

 Pastasa, and the latter river flows along its western 

 foot ; a little north of west from Puca-yacu, the 

 course of the Pastasa is indicated by a deep gorge 

 stretching west from behind the riclge. This gorge 

 has on each side lofty rugged mountains (5000 to 

 6000 feet), spurs of the Cordillera ; one of those on 

 the right is called Abitagua, and the track from 

 Canelos to Banos passes over its summit. All this 

 was frequently visible, but it was only when the 

 mist rolled away from the plain a little after sun- 

 rise that the lofty Cordillera beyond lay in cloud- 

 less majesty. To the extreme left (south), at no 

 very great distance, rose Sangahy (or the Volcan 

 of Macas, as it is often called), remarkable for its 

 exactly conical outline, for the snow lying on it in 

 longish stripes, and for the cloud of smoke almost 

 constantly hovering over it. A good way to the 

 right is the much loftier mountain called Los 

 Altares, its truncated summit jagged with eight 

 peaks of nearly equal elevation and clad with an 

 unbroken covering of snow, which glittered like 

 crystal in the sun's rays, and made me think how 

 pure must be the offering on " altars " to whose 

 height no mortal must hope to attain. Not far to 

 the right of Los Altares, and of equal altitude, is 

 Tunguragua, a bluff irregular peak with rounded 

 apex capped with snow, which also descends in 



