540 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1910. 



The eggs are rather variable in shape. One which I have from the 

 Orinoco is elliptical, while my Abary specimens are oval. The 

 ground color is creamy white. The entire surface is marked with 

 small, irregularly shaped dots and spots of reddish brown, inclining 

 to be more abundant at the large end. The brown pigment de- 

 posited early in the oviduct is covered by a thin layer of lime and 

 thereby given a lavender hue. The size averages 1.8 by 1.3 inches. 



ENEMIES. 



Hoatzins seem to be very free from enemies, although from year 

 to year their numbers remain about the same. The waters beneath 

 them are inhabited by otters, crocodiles, anacondas, and voracious 

 fish, so that death lies that way. They seem also to fear some preda- 

 tory bird, for whenever a harmless hawk skims over the branches on 

 the lookout for lizards, the hoatzins always tumble pell-mell into the 

 shelter of the thick foliage below. 



PHOTOGRAPHING HOATZINS. 



We found that the best time to approach and photograph the 

 birds was during their siesta. As we paddle along the bank, they 

 scramble from their perches or nests up to the bare branches over- 

 head, calling hoarsely to one another. Pushing aside the dense 

 growth of arums and vines, we work our canoe as far as possible 

 into the heart of the brush to the foot of some good-sized marsh tree 

 perhaps a foot in diameter. I step from the boat to the lowest limb, 

 Mrs. Beebe hands me the big Graflex with the unwieldy but neces- 

 sary 27-inch lens, and I begin my painful ascent. At first all is 

 easy-going, but as I ascend I break off numerous dead twigs, and 

 from the broken stub of each issues a horde of black stinging ants. 

 These hasten my ascent and at last I make my way out on the sway- 

 ing upper branches (pi. 5, fig. 1). From here I have a fairly clear 

 view of the surrounding brush, and if I work rapidly I can secure 

 three or four pictures before the hoatzins take flight and hide amid 

 the foliage. 



Of all my pictures, that of plate 3 is the prize. We came upon a 

 flock of hoatzins late in the afternoon and were fortunate enough to 

 get into a clear space and to photograph 11 on the same plate; the 

 confused mass near the center of the picture containing four indi- 

 viduals. Plate 4, figure 1, shows the character of the country where 

 we found the hoatzin on Abary Creek, with the line of dense growth 

 on one side and the level savanna on the other. 



A photographic study of an individual pair of birds is given in 

 plate 5, figure 2, to plate 7. The action of these two birds is so typi- 



