observed in the Gran Chaco. 231 



81. Cathartes atratus (Bartram). 

 Villa Concepcion; W. Very abundant. 



Fam. XXIV. PHALACROCORACIDiE. 



82. PhALACROCORAX BHASILIANUS (Gm.) . 



Phalacroct,rax vigua Grant, B. M. C. B. xxvi. p. 378. 



Villa Concepcion, Sept. 27. Very many on Riacho Verde, 

 Feb. 25. 



W. Very common in the wet season about open water 

 at the edge of swamps ; the birds sit on palms or palm- 

 stumps on the watch for fishes. When disturbed they will 

 fly round and round at a small elevation, and it is a favourite 

 sport with the Lenguas to try to bring them down by 

 whirling a stout stick some two feet long amongst them 

 as they pass. 



Fam. XXV. Plotid^. 



83. Plotus anhinga Linn. 

 Villa Concepcion. 



Very common on Rio Paraguay, Oct, 1896. Perches at 

 nightfall on tall trees. During the day seen swimming or 

 resting on dead trees by the water's edge. Often disappears 

 beneath the surface for some time. On trees it will sit with 

 the wings half spread out as if sunning itself. 



Fam. XXVI. A r d e i d ^. 



84. Ardea cocoi Linn. 



Villa Concepcion, Sept. 28. Common. W. 



85. Ardea egretta (Wils.). 



Villa Concepcion : flock, Oct. 10. W., Dec. 16, several ; 

 flock, Dec. 30. Near W., Feb. 16. 



On Feb. 25th, when passing a tributary of the Riacho 

 Verde, we found an enormous assemblage of Herons con- 

 taining several hundreds of individuals, and amongst them 

 this species was the most numerous. 



86. Ardea candidissima (Gm.). 



W., Dec. 1, Dec. 16. Riacho Verde, Feb. 25, 



