48 A MANUAL OF THE BIRDS OF AUSTRALIA. 



large amount of bare skin between the frontal feathering and the culminicorn as 

 well as between the culminicorn and the latericorns, while the basal bar shows the 

 method of disappearance of the lower mandible stripe seen in the next group. This 

 is Phcebetria, the dark plumaged Antarctic forms with long wedge-shaped tails and 

 with the bill showing the culminicorn entering the frontal feathering at an acute 

 angle, and with a naked strip of skin along the sides of the lower mandible. We 

 considered this showed the most primitive features, and that independently the 

 other genera have evolved from the same source, the Thalassarche group showing 

 the loss of the lower mandibular ramal streak, a basal bar remaining to indicate 

 its presence, while Diomedella has the basal bar still retaining marks of its reduction 

 while in size it is less than Diomedea which has no trace of the bar but shows the 

 feathering of the face entering at an angle the base of the lower mandible. We 

 would therefore conclude that this largest series was the furthest developed, and 

 we find that a professional anatomist ignorant of these items also concluded : 

 " Phoebeiria is probably the most primitive." 



Osteologically, the lack of basipterygoid processes, the tendency to fusion by 

 the conjunction of the vomer and maxillo-palatines and the peculiarity of the former, 

 the characteristic pterygoids all characterise the skull in this group. The wing 

 muscles are complicated as would be anticipated by the extreme development 

 of the wing. The thoracic vertebrae also differ in the absence of hypapophyses and 

 the pelvis is more specialised than in the preceding superfamily. 



Between the anterior ends of the mandibular rami there is a narrow strip of 

 horn, known as the interramicorn, which is not found in other Petrels outside this 

 superfamily. 



FAMILY DIOMEDEIDJE. 



Genus PHGEBETRIA. 



Phcebetria Reichenbach, Nat. Syst. Vogel, p. v., 1852 (? 1853). Type (by original designation) : 

 Diomedea fuliginosa Gmelin. 



Medium Albatrosses of dark coloration, with long bills, long wings, long wedge- 

 shaped tail and medium legs and feet. 



The bill is characterised by the presence of a deep groove along the sides of the 

 lower mandible filled with a loose, coloured skin. The culminicorn slopes backward, 

 meeting the frontal feathers at a sharp angle but descending behind the nasal 

 openings to meet the latericorn ; the nostrils are placed near to the base of the culmen, 

 opening as semicircular tubes, sometimes termed " naricorns " ; the unguis is com- 

 paratively weak, the latericorns not much expanded laterally, consequently the bill 

 is somewhat compressed laterally. The lower mandible has a deep groove absent 

 in other Albatrosses, feathering of the face approaching far forward. The wing is 

 long, the feathers somewhat pointed and secondaries fewer than in Diomedea. The 

 tail is composed of long narrow feathers forming a strong wedge and is almost half 

 the length of the wing and about twice the length of the culmen. The legs are stout, 

 the tarsus only about three-fourths the length of the culmen and about four-fifths the 

 length of the middle toe. There is no hiud-toe, and the anterior toes are fully webbed . 



Coloration entirely dusky. 



37. Phcebetria fusca. SOOTY ALBATROSS. 



[Diomedea fusca Hilsenberg, in Froriep's Notizen, Vol. III., No. 5 (49), p. 74, Sept. 1822 r 

 Mozambique Channel. Extra-limital.] 



Gould, Vol. VII., pi. 44 (pt. xxxvi.), Dec. 1st, 1848. 



