1867.] PROF. HUXLEY ON THE CLASSIFICATION OF BIRDS. 4(51 



the other, that it can be ranged with neither of these groups, but 

 must stand as the type of a division by itself. 



Thus the skull has the long lachrymo-nasal region, the basiptery- 

 goid facets, the prolonged and recurved angle of the mandibles, the 

 laminated horny sheath of the Chenomorphre ; but the maxillo- 

 palatines are spongy, and the general structure of the rostrum is quite 

 similar to that found in the Storks and Herons. 



The lower end of the crus is bare ; but the feet are fully webbed, 

 and the pterylosis is said by Nitzsch to be " completely Stork- 

 like." 



-^3. The PELARGOMORPHiE. 



There are no basipterygoid processes, and the palatines usually 

 unite for a greater or less distance behind the posterior nares ; but 

 they send down no vertical plate from their junction. 



The maxillo-palatines are large and spongy. 



The angle of the mandible is truncated (except in Platalea and 

 Ibis). 



The sternum is broad, and may have two or four posterior notches. 



The hallux varies in its proportions, but is not turned forwards or 

 inwards, or united by a web with the other toes, the web between 

 which is always incomplete. The ratio of the phalanges is as in the 

 preceding groups. 



The oil-gland is surmounted by a circlet. 



The disposition of the carotids and the characters of the larynx vary. 



I associate in this division the Herodice, Pelurfji, and Hemiylot- 

 tides of Nitzsch. The last group, including the genera Ibis and 

 Platalea, differs from the rest in having a produced and recurved 

 mandibular angle, and in some other respects approaches Phcenito- 

 pterus. The typical forms incline rather to the succeeding group. 



-^A. The Dysporomorph^. 



The rostrum is long and pointed and more or less curved, and the 

 external nasal apertures are very small. There are no basipterygoid 

 processes. The palate-bones unite for a considerable distance be- 

 hind the posterior nares, and send down a vertical crest from their 

 junction. 



The maxillo-palatines are large and spongy. 



The angle of the mandible is truncated. 



The sternum is broad, and its truncated posterior edge is either 

 entire or has a shallow excavation on each side of the middle line. 



The hallux is turned forwards or inwards, and is united by a web 

 with the completely webbed anterior toes. The ratio of the pha- 

 langes is as in the preceding genera. 



The oil-gland is surmounted by a circlet of feathers. 



This group answ'ers to the " Steganopodes " of Illiger ; and since 

 the appearance of the admirable memoir of Brandt, ' Zur Osteologie 

 der Vogel,' in 1840, no doubt can have been entertained as to its 

 extremely natural characters. The genera composing it are sharply 



