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ORDER ANSERES. 
GENUS XXXV. 
PROCELLARIA PETREL. 
This genus contains twenty five species 
of Birds. Its distinguishing characters are : 
Beak toothless, a little compressed, 
hooked at the point, mandibles equal. 
Nostrils cylindrical, tubular, truncate* 
lying on the base of the beak. 
Feet palmate, the back toe pointing 
downwards, sessile, sharp, a mere spur. 
Of all the marine birds, those which the 
most constantly live on the open seas are the 
Petrels ; they are the greatest strangers to 
the land, and the most adventurous in roving 
on the vast ocean : they commit themselves 
with equal confidence and audacity to the 
rolling billows, the impetuous winds, and 
seem to brave the fury of the tempests. In 
