60 BULLETIN 133, UNITED STATES NATIONAL MUSEUM 



blue heron. They were seen in flight to various feeding grounds at 

 dusk. At a large lagoon at Kilometer 110 they were fairly common 

 and were encountered among rushes, from which they flushed with a 

 low note that resembled took xook. 



In the Guarani language the species was known as hoc.6. The 

 adult was called nhe ha na by the Anguetes, while the bird in barred 

 immature plumage was known as ca pi a tik. 



IXOBRYCHUS INVOLUCRIS (Vieillot) 



Ardea involucris Vieillot, Eucyc. Meth., vol. 3, 1823, p. 1127. (Paraguay.) 



Azara's least bittern is similar in haunt and habit to the least 

 bittern of the West Indies and the United States, so that it may be 

 more common than would appear from the few occasions on which I 

 encountered it. On October 31, 1920, at the Estancia Los Yngleses, 

 near Lavalle, Buenos Aires, while wading about in water nearly to 

 my knees, I saw three among rushes in a caiiadon. The birds were 

 wild, flushed at a distance of 60 meters, and flew rapidly away above 

 the marsh vegetation, to drop down again when at a considerable dis- 

 tance away. A male was killed at long range on this date and one 

 was taken on November 2. Another was seen November 9, The 

 birds appear light in color when flying and are of surprisingly rapid 

 flight for a bird of this group. At Carhue, Buenos Aires, one flushed 

 from a clump of cattails in an arroyo on December 15 and one was 

 seen the following day. One was recorded at the Laguna Castillos, 

 south of San Vicente, Uruguay, on January 31, 1921. 



Family CICONIIDAE 



JABIRU MYCTERIA (Lichtenstein) 



Ciconia mycteria Lichtenstein, Abhaudl. Kon. Akad., Wiss. Berlin (Phys. 

 Klass.) for 1816-17, 1819, p. 163. (Brazil.) 



At the Eiacho Pilaga, Formosa, two jabirus were seen on August 

 16, 1920, as they soared at least 1,000 meters above the earth. The 

 birds, in appearance snow white with dark heads, turned in short 

 circles with set wings, and finally sailed away out of sight. At Puerto 

 Pinasco, Paraguay, on September 3 one passed high overhead. I had 

 no other opportunity to observe this species. 



MYCTERIA AMERICANA Linnaeus 



Mycteria americana Linnaeus, Syst. Nat., ed. 10, vol. 1, 1758, p. 140. 

 (Brazil.) 



On November 16, 1920, a flock of 12 wood ibis was noted between 

 Lavalle and Santo Domingo, Buenos Aires; the species was seen 

 nowhere else in Argentina. At the Laguna Castillos, below San 



