Order XX. TUBINARES. 



The Petrels were formerly classed with the Grulls, to which they 

 have a considerable external resemblance, although they differ in 

 many important characters, and they appear, on the whole, to be 

 as nearly allied to the Steganopodes as to any other order. They 

 may be at once distinguished from all other birds by the nostrils 

 terminating externally in tubes, separate or united. The rham- 

 photheca or horny covering of the bill is divided into several 

 pieces by deep grooves, as in some Steganopodes, and the upper 

 mandible is generally much hooked at the end. The anterior toes 

 are webbed throughout, the hallux is small, rudimentary or absent, 

 being frequently represented by the claw-phalanx alone. The 

 wings are long in the typical forms, the primaries 11, the filth 

 secondary wanting. Oil-gland tufted. Spinal feather-tract well- 

 defined on the neck by lateral bare tracts ; forked on the upper 

 back. 



Petrels are schizognathous and holorhinal. The vomer is large, 

 broad, depressed, and pointed. Nostrils impervious. Cervical 

 vertebra? 15. Large supraorbital glands ; two carotids ; caeca rudi- 

 mentary or wanting. Femoro-caudal and semitendinosus muscles 

 always present, ambiens and accessory fernoro-caudal generally, 

 but wanting in a few genera. 



The majority of the species lay a single egg in a burrow or 

 under stones, without any nest. Some, as the Albatrosses, make 

 a nest in the open. The egg is either entirely white or has a 

 faint zone of reddish spots near the larger end. The young are 

 helpless, and clad with down till fully grown. Sexes alike in 

 coloration. 



The Petrels are birds of the ocean, passing the greater part of 

 their life far from land, resting on the water at times, and only 

 visiting the shore, as a ride, for breeding purposes. They feed on 

 floating Crustacea, mollusca, small n'sh, alive or dead, and similar 

 aliment. Some of them, as the Fulmars and Dapt'wn, follow 

 ships and feed on any refuse, especially fat, that may be thrown 

 overboard. Most of the Petrels are swift and powerful flyers, 

 and may be seen skimming over the waves, almost without moving 

 their wings, whilst some of them, and especially the small Stormy 

 Petrels, appear to aid their flight by striking the water with their 

 feet. Hence, as Newton points out in his * Dictionary of Birds,' 

 their name of Petrel was derived, for they were supposed to be 

 walking on the sea as St. Peter is recorded to have done. 



Many Petrels are crepuscular or nocturnal, especially during the 

 breeding-season. The majority of them, on being captured, vomit 

 a small quantity of clear oil with a disagreeable smell. 



The classification of the Petrels, like their systematic position, 

 is still unsettled. By many the Albatrosses are placed in a 



