248 FISHERIES OF THE ORIENTAL REGION, 



night time, the fish being attracted by lights and fires. They are 

 lightly salted, pressed and sun-dried. All kinds are eaten, but 

 the best is the little Seplola, which is really a dainty morsel when 

 properly cooked. 



Note on the Aerial Respiration op Fishes. — Professor 

 Jobei-t of Dijon, who was lately engaged in making some 

 zoological investigations in Brazil, at the instance of the Emperor 

 Don Pedro, has ascertained some exceedingly remarkable facts in 

 connection with the respiration of certain fishes. A Siliiroid fish 

 which inhabits the neighbourhood of Rio de Janeiro {CalUclithys 

 asper) and is noted for its power of living a long time out of the 

 water, was found by him to swallow small portions of air, from 

 which it partly absorbs the oxygen by the agency of the walls of 

 the intestinal canal ; the carbonic acid formed and the unabsorbed 

 nitrogen passing away by the anal aperture. On examining the 

 structui'e of the intestine, Professor Jobert found its inner surface 

 bearing a multitude of filiform appendages arranged in tufts and 

 composed essentially of blood-vessels. 



A somewhat analogous case was observed in several other fishes 

 inhabiting the valley of the Amazon. They live in stagnant water 

 the temperature of which often exceeds 104° F. ; but this does 

 not appear to be sufficient to support their respiration, and they 

 are obliged to come frequently to the surface for a supply of air. 

 Sometimes also, the water in which they have been living is dried 

 up, when they are seen making considerable journeys by land in 

 search of more favourable localities, crawling on the ground by 

 means of their pectoral fins. Some of these are species of Cal- 

 lichthys, and like the C. asper of Rio de Janeiro, they possess a 

 double respiration — respiring the air contained in the water 

 surrounding them by means of their gills, and also the atmospheric 

 air which they swallow, and which passes through their intestine. 

 The escape of the exhausted air from the anal aperture of these 

 fishes is said to produce a constant bubbling in the water which 

 they inhabit, and M. Jobert's investigations, though imperfect, 

 sufficed to convince him that the air evacuated contained much 



