BIRDS OF ARGENTINA, PARAGUAY, URUGUAY, AND CHILE 141 



of the present species save that the crown is described as nearly 

 white and the legs as red. The crown in the immature large-billed 

 tern is pale gray, while the feet are yellow. The size, color of the 

 wing coverts, large bill, and forking of the tail are those of Phaetxisa, 

 and the head, while not true white, is lighter than the back and 

 might be characterized as " nearly white." It is my opinion that the 

 present species may be recognized from this description, which can 

 not refer to any other tern of this region. Gmelin in translating 

 Latham's English into Latin wrote "vertice * * * alba," but 

 this has no consequence, as Gmelin had no specimens but simply 

 took what Latham had said regarding the bird. The " variety a " 

 of Latham's simple tern which follows refers to some other species. 



The name of the large-billed tern, therefore, becomes Phaetufsa 

 svrnplex Gmelin with the type locality Cayenne. The southern form 

 will stand as Phaetusa s. chloropoda Vieillot. Sterna hrevirostris 

 Vieillot^" based on the hati fico corto of Azara, a name that has 

 been assigned doubtfully to the present bird, is based on the imma- 

 ture of some other species. Otherwise it would have priority over 

 chloropoda. 



Specimens of the northern form have been seen (in the collections 

 of the United States National Museum, the Field Museum of Natural 

 History, the Academy of Natural Sciences, and the Museum of Com.- 

 parative Zoology) from Colombia (Barranquilla), Venezuela (Punta 

 Caiman, Manimo River, Eio Uracoa, Aruba Island, Lake Valencia), 

 British Guiana (Georgetown), Dutch Guiana (Braamspunt, Tyger- 

 bank, Diana Creek), and Brazil (Serra Grande and Conceicao, 

 Amazonas, Santarem and Pernambuco). The southern form is rep- 

 sented in the Museum of Comparative Zoologj^ bj^ skins from Con- 

 cepcion del Uruguay . (collected by Barrows) in addition to the 

 localities that have been noted. It seems probable that P. s. chloro- 

 poda is found in the Paraguay-Parana drainage and that P. s. sim- 

 plex covers the river basins of northern South America. 



Family JACANIDAE 



JACANA JACANA (Linnaeus) 

 Parra jacana Linnaeus, Syst. Nat., ed. 12, vol. 1, 1766, p. 259. (Surinam.") 



The jacana, common in the Chaco and in parts of Uruguay, was 

 recorded at the following points : Resistencia, Chaco, July 9 and 10, 

 1920; Las Palma.5, Chaco, July 17 to 31; Riacho Pilaga, Formosa, 

 August 9 to 17; Formosa, Formosa, August 23; Puerto Pinasco, 

 Paraguay, September 1 to 30 (found from the Rio Paraguay, west 



^Nouv. Diet Hist. Nat, vol. 32, 1819, p. 16C. 



^ See Berlepsch and Hartert, Nov. Zoo!., vol. 0, .Vpril, 1002, p. 121). 



