NO. 2298. 



THE GUANO BIRDS OF PERU—COKER. 



465 



in the sun one morning and know that they had first eaten all they 

 had wanted. 



A great many nests were examined, to find in each nest, if tenanted, 

 only one egg or one young bird. The eggs are purest white, with 

 very thin shells, and they are very variable in shape. Some are short 

 and well rounded, with little difference between the ends, while others 

 are very elongated and rather pointed at the smaller end. The 

 measurements of six eggs of the potoyuncos were as follows: 



Dimensions, in centimeters, of eggs of Pelecanoides garnoti. 



A "pichon, " or fledgling, at the stage when the wing feathers are 

 first appearing, is a large shapeless mass of fat and down, with nearly 

 the dimensions of its parents and of equal weight (about 7 ounces). 

 Its soft coating of gray down measm-es 3-4 cm. in thickness (1^ 

 inches, more or less). If a single tul"t of down is pulled out, there is 

 found growing out of the blue sheath the delicate little feather, which 

 for about 1 cm. is white (if from the lower side of the body) or black 

 (if from the back) ; many of its barbs are tipped with dehcate plumes 

 of down, which are dark gray for about 2 cm. and possess white tips 

 of 1 cm. length. The head protruding from this great baU of down 

 appears almost bald having only a close crop of gray down. 



Valued as they are for food and readily open to capture, the poto- 

 yunco must eventually be brought near to extinction unless effective 

 efforts for its protection are made. It will be unfortunate, indeed, if 

 the potoyunco and the penguin, two water fowl which produce a 

 fertilizer of high quahty, shall, through mere human negUgence or 

 wastefulness, become lost to the guano industry. Valuable the poto- 

 yuncos may be as food, or the penguins for the skins or fat, and we 

 may impose little personal blame on those who desire the food or the 

 skins or the oils; but the fact remains that when the food or the skin 

 and oil is taken the bird is lost to the future, while the removal of 

 the guano is a benefit gained without loss. With due care each of 

 these important species may not only be preserved to the future, but 

 may be restored to a condition of far greater abundance and value 

 than at the present time. 



THE GANNETS. 



The Sulidae or gannets are represented on the Peruvian coast by 

 two species, the abundant -S'wZavan6g'ato(Tschudi), third in importance 



115690— 19— Proc.N.M. vol.56 30 



