Gentjs^D I 0 M E D E a . 
Diomedea Linn4, Syst. Nat., ed. X., p. 132, 1758 . . . . Type D. exulans, 
(Also B^elt Dio7nedia Linne, Syst. Nat., ed. XIL, p. 215, 1766 ; 
Dio7nedcea Lesson, Ann. Sci. Nat., Vol. VI., p. 94, 1825 ; 
Dio7ncedea, id., Traite d’Orn., p. 609, 1831.) 
Albatrossa Brunnich, Zool. Fund., p. 80, 1771 . . . . Type D. exulans. 
Alhatros Lesson, Manuel d’Orn., Vol. II., p. 389, 1828 . . Type D. exulans. 
Large Petrels, separable from the other members of the order by the position 
and nature of the nasal orifices as well as by their large size. In addition, the 
majority have no groove on the sides of the lower mandible, and all possess a 
corneous piece between the lower mandible rami at their anterior end (known 
as the inter-ramicorn). 
The nasal orifices are situated on each side of a broad culmen, and though 
generally spoken of as tubular, are of a peculiar semi-tubular nature. The 
wings are extremely long, but very narrow, with the first primary longest, 
while the tail is rounded or wedge-shaped. The bill is longer than the head, 
and about the length of the middle-toe which is longer than the tarsus. 
Hind-toe absent. 
The preceding diagnosis covers all the members of the family Dio 7 nedeidcB, 
which are well marked off from the remainder of the order Procellariifor7nes. 
Cones considered this a subfamily, and admitted two genera only, Dio7nedea 
and Phcebetria. His conclusions can be best considered in his own words : 
“ In the following pages I describe eleven species ... Of these one differs 
so much from the rest that it may be properly made the type of a genus dis- 
tinct from Dio7nedea. The remaining species have also been sub-divided into 
several genera . . . Such a collocation of species is certainly natural ... So 
varying are the characters of shape of bill, outline of frontal feathers, length 
of tail, etc., that I think they can hardly be made typical of distinct genera.” 
Coues showed that the large Albatroses were grouped together by general 
features, and that the Mollymawks also formed a somewhat natural group, 
and though he would now be regarded as a genus-splitter, in this case he 
considered lumping to be the best policy. 
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