71 



Order XII. PODICIPEDIFORMES *. (Cosmopolitan.; 

 Suborder xvi. Podicipedides. 

 Fam. PoDicrpEDiD^. 



Order XIH. COLYMBIFOEMES f. (Arctic and Sub-Arctic.) 

 Suborder xvii. Colymbi. 



Fam. COLYTMBID^. 



Order XIV. SPHENISCIFORMES J. 

 Suborder xviii. Impennes. 

 Fam. Aptenodytid^. 



Order XV. PROCELLARIIFORMES§. (Cosmopolitan: Pelagic.) 

 Suborder xix. Tubinares. 

 Fam. 1. DiOJiEDEiD.^. 



2. Procellaeiid^. 



3. Pelecanoid^. 



* Cnemial process of tibia produced forwards to a remarkable degree; posterior 

 process of the ilium approximated to such an extent that the sacrum is almost entirely 

 concealed ; palate scliizogiiatbous ; cervical vertebrte 17 to 21 in number ; anchylosed 

 sacral vertebrae preceded by a free vertebra, in front of which are four anchylosed dorsal 

 vertebras ; median xiphoid process of sternum abruptly truncated, so that the lateral 

 processes extend behind it. {Cf. Seebohm, Classif. B. p. 41.) Spinal feather-tract not 

 defined on neck ; ambiens and femoro-caudal muscles absent. For other characters 

 cf. Stejneger, S. N. H. p. 66. Toes lobate ; rectrices obsolete. Nest, a mass of stalks 

 and rubbish floating on the water. Eggs white. Young covered with down when 

 hatched, and able to swim at once. Plumage of nestlings striped. 



t Cnemial process and posterior processes of the ilium as iu the Podicipedides ; no 

 anchylosed vertebrae in front of the anchylosed sacral vertebrae ; median xiphoid pro- 

 cess of sternum projecting behind the lateral processes ; number of cervical vertebrae 

 14 or 15. (Seebohm, Classif. B. p. 41.) Ambiens and femoro-caudal muscles present. 

 Toes four ; legs placed far back. Nest in freshwater lakes. Eggs two, dark olive- 

 brovsTi. Young hatched covered with down. 



X Palate schizognathous ; first digit of manus fused with the second iu the adult ; 

 scapula very broad, not differing very much in size from the keel of the sternum ; 

 three metatarsal bones of tarsus very sh:rt and separated from each other throughout 

 by deep grooves ; bones of forearm all flattened. (Seebohm, t. c. p. 35.) Spinal feather- 

 tract not defined on nape ; none of the wing-feathers differentiated in quills. For 

 numerous other characters see Watson's ' Challenger ' Report, and Stejneger, S. N. H. 

 p. 56, Nest a rude structure of grass in the open or in a burrow. Eggs two, white or 

 greenish white. Young when hatched thickly covered with down. 



§ External nostrils produced into tubes ; nasals holorhinal ; dorsal vertebras hetero- 

 coelous ; basipterygoid processes absent in Biomedeidce and Procellariida, but present 

 in Pelecanoidee ; hallux absent or reduced to one phalanx, the other toes directed 

 forwards ; spinal feather-tract well-defined on neck ; oil-gland tufted. (Seebohm, t. c. 

 p. 34, and Stjeueger, t. c. p. 84.) Nest none ; egg usually concealed in a hole or 



