220 Mr. J. G. Kerr on the Birds 



to a part of the swamp where the frequent splashes all round 

 tell him o£ the abundance of teleostean fishes ; there he 

 pulls the vegetation aside so as to make a clear pool one or 

 two yards in diameter^ throws into it some fragments of the 

 big Amjmllaria to serve as ground-bait^ and then proceeds 

 to angle with a rude fishing-rod^ baiting his hook with the 

 muscular foot of the gasteropod. By the latter method in 

 particular he catches two species of Characinidae — Macrodon 

 trahira and Erythrinus unitcsniaius. These species, as 

 also Callichtliys asper, C. littoralis, and Symbranchus mar- 

 moratus, form, together with LejAdosiren, the main fish- 

 diet of the Indians. Sometimes a party of fishermen are 

 fortunate enough to kill a large Boa, the flesh of which is 

 also very good eating. The Jacare, probably on account of 

 the denseness of the vegetation, seldom wanders into the 

 swamp, though it occurs in the sluggish streams into which 

 the waters drain. After the rains cease, when the whole of 

 the marsh dries up, the Jacare retires underground, leaving 

 only a tubular channel to communicate with the upper air, 

 and is thus able to survive till the next rainy season, in the 

 same way as do Lepidosiren, Synibranchus, and Ampullaria. 

 In the height of the wet season the swamp is bounded on all 

 sides by a fringe of more or less open water. Here, where 

 there are half-prostrate palms suitable for perches, is to be 

 heard the weird drumming sound of the Brazilian Cor- 

 morant, large numbers of these birds congregating to feed 

 upon the fish-fry. As the visitor passes beyond the water's 

 edge, if the ground is bare, he will probably disturb a flock 

 of five or sixNaeunda Goatsuckers {Podager nacunda), which 

 lie until he is quite close to them and then rise uttering a 

 soft cry, to flit away a little distance and then alight again, 

 vanishing from view as if by magic the moment they touch 

 the earth. 



Beyond the margin of the swamp is the palmar, that type 

 of scenery so characteristic of the Chaco— a wide-spreading 

 savannah covered with dense coarse grass and dotted with 

 fan-palms {Copernicia cerifera). Here and there are dead 

 palm- stems which, when erect, form the nesting- places of 

 various Ducks, Parrots, and so forth and, when prostrate, 



