BIRDS OF ARGENTINA, PARAGUAY, URUGUAY, AND CHILE 59 



male shot at the same locality on September 20 has the following 

 measurements: Wing, 358; tail, 127.5; exposed culmen, 106; tarsus, 

 112. Both of these birds are in full plumage and are similar save 

 that the female, in addition to being slightly smaller, is paler 

 throughout, and has the lower neck barred with black on the sides 

 and behind. A third bird, a female, shot 110 kilometers west of 

 Puerto Pinasco on September 23 is identified as the present species 

 with some reservation. It is juvenile, molting from ju venal plumage, 

 and may represent holivianuin instead of viai^iioraturri. In color it 

 is buff barred with black, as usual in young tiger bitterns, save that 

 the black bars are more restricted in width than in other specimens 

 examined. The crown and hind neck vary from mikado brown to 

 cinnamon, barred narrowly with black. New feathers that are ap- 

 pearing on the upper back are dull black, barred narrowly with wavy, 

 irregular bars of cinnamon; others on the sides of the foreneck are 

 russet margined tipped and barred with black. This bird measures 

 as follows: Wing, 316; tail, 115.5; exposed culmen, 99; tarsus, 108 

 mm. 



It is probable that Tigrisoma marmoratuTn will prove to be a sub- 

 species of T. Imeatum^ a species of northern range, from which it 

 differs mainly in larger size as far as may be judged from available 

 descriptions. 



The tiger bittern is a species that frequents open shores of marshy 

 lagoons, often among growths of cattails or other rushes. Two 

 ranged about a lagoon at the Riacho Pilaga in Formosa during 

 August, 1920, but were wild and wary. On one occasion I knocked 

 one over with a broken wing and waded for it in Avater reaching to 

 my armpits, but was so impeded by mud and aquatic growth that the 

 heron swam to a mass of floating vegetation and was lost before I 

 reached it. Near Kilometer 80, west of Puerto Pinasco, Paraguay, 

 three were observed in Laguna Palmas, where they walked about on 

 floating plants that choked the Avater. When they flushed, one 

 alighted on a shaded perch in a tree, where I stalked it and shot it. 

 This bird, an adult female, had the bill black, with the lower half of 

 the mandible pale olive-buff, a color that extended along the gonys 

 to ih& tip ; bare skin from above eye to base of bill, wax yellow ; a line 

 from anterior canthus of eye to bill, and another above commissure 

 to below eye, deep neutral gray ; rest of bare skin on side of head and 

 over ramus of lower jaw, citron yellow; iris antimony yellow; front 

 of tarsus, and toes shading from chaetura black to chaetura drab; 

 back of tarsus for upper half varying from tea green to vetiver 

 green. 



The flight of these herons is slow and direct, accomplished with 

 slowly flapping wings, and in the air they appear as large as a great 



