400 



They are three or four feet long; and bending 

 their back, and pressing with their tail on the 

 inferior strata of the water, they expose to view 

 a part of the back and of the dorsal fin. I did 

 not succeed in obtaining any, though I often 

 engaged the Indians to shoot at them with their 

 arrows. Father Gili asserts, that the Gumaoes 

 eat their flesh. Are these cetaceous animals pe- 

 culiar to the great rivers of South America, like 

 the manatee, which, according to the anatomical 

 researches of Mr. Cuvier, is also a fresh water 

 cetaceous animal? or must we admit, that they 

 go up from the sea against the current, as the 

 delphinaptera beluga sometimes does in the 

 rivers of Asia ? What would lead me to doubt 

 this last supposition is, that we saw toninas 

 above the great cataracts of the Oroonoko, in the 

 Rio Atapabo. Did they penetrate into the centre 

 of equinoctial America from the mouth of the 

 Amazon, by the communication of this river 

 with the Rio Negro, the Cassiquiare, and the 

 Oroonoko ? They are found here at all seasons, 

 and nothing seems to announce, that they make 

 periodical voyages like salmon. 



While the thunder rolled around us, the sky 

 yet displayed only scattered clouds, that ad- 

 vanced slowly toward the zenith, and in an op- 

 posite direction. The hygrometer of Deluc was 

 at 53°; the centigrade thermometer, 23*7° *. 



* Hygrometer of Saussure, 87*5° ; th. 19° R. 



