90 PICARIAN BIRDS. 



noiseless flight much resembles that of goatsuckers ; but in descending rapidly the 

 wings are frequently raised and held together in a point. Their principal food 

 consists of the fruit of the nectandra trees ; these fruits being seized by the birds 

 while in full flight from the tips of the slender boughs which would be too frail to 

 bear the weight of the robbers. For seizing such fruits the hooked and powerful 

 bill of the oil-bird is most admirably adapted. The rapidity with which the 

 guacharos feed is remarkable ; two specimens killed by Stolzmann early one 

 evening having their crops empty, whereas one shot a quarter of an hour later had 

 swallowed seven fruits, and a second bagged after another quarter of an hour no 

 less than eleven. The same observer remarks that it would be curious to know 

 what the birds did for the remainder of the night, after having satisfied their 

 appetite, for he has seen them in moonlight evenings on the wing as late as eleven. 

 The note of the guacharo is harsh and disagreeable, and has been compared to the 

 syllables cri-cri-cirri ; although there is another cry which cannot be rendered in 

 words. From observations on a young bird, in the grey nestling plumage, Stolz- 

 mann found that the large nectandra stones are regurgitated after the fleshy 

 covering has been digested. This rejecting process is accomplished without any 

 apparent effort on the part of the bird ; a slight movement of the feathers of the 

 throat takes place, the beak opens gently, and the stone appears ; while, if any of 

 the fleshy covering still adheres to it, the bird picks it off. The old birds appar- 

 ently cast up the stones during flight ; and although no insects were found in the 

 stomachs of the specimens shot, Stolzmann is of opinion that guacharos are partly 

 insectivorous. Humboldt and Bonpland visited the celebrated cavern of Caripe, 

 from whence these birds take their specific name ; and the following account of the 

 visit is taken from a biographical work. " The Indians," it is written, " showed 

 the travellers the nests of the guacharos by fixing a torch to a long pole. These 

 nests were fifty or sixty feet high above their heads, in holes in the shape of 

 funnels, with which the roof of the grotto was pierced like a sieve. The noise 

 increased as the travellers advanced, and the birds were scared by the light of the 

 torches. When this noise ceased for a few minutes, around them they heard at a 

 distance the plaintive cry of the birds roosting in other ramifications of the cavern : 

 and it seemed as if different groups answered each other alternately. The Indians 

 were in the habit of entering this cavern once a year, near midsummer ; when they 

 went armed with poles, with which they destroyed the greater part of the nests. 

 At that season several thousand birds were killed ; and the old ones, as if to defend 

 their brood, hovered over the heads of the Indians, uttering terrible cries. The 

 young, which fell to the ground, were opened on the spot for their fat. At the 

 period commonly called at Caripe the oil-harvest, the Indians built huts with palm 

 leaves near the entrance, and even in the porch of the cavern. There, with a fire 

 of brushwood, they melted in pots of clay the fat of the young birds just killed ; 

 this fat being known by the name of guacharo-butter." The nest is formed of 

 clay ; and the eggs, varying from two to four in number, have a thick shell, which 

 is at first chalky white, but by contact with the nest becomes yellowish green. 



R. BOWDLER SHARPE. 



