OI£Dl!;i{ PVGOI'ODES— THE DIVING UIUDS. 251 



OrmEu PYGOPODES.— The Diving Birds. 



Chabactebs. Legs inserted tar backward, the taisi extremely compressed. Anterior 

 toes fully webbed or idse strongly lobeJ and witli broad Hat nails fPoilicipiaa;). Bill cx- 

 treino'.y variable. Habits rripcocial in PoJicOnV/"' and Volymbidd-, altricial in Alvidir: 

 younj; dasypaidie. Palate schizognallious. Carotids double, except in Podiciijidiv and 

 some Alcidie (e. g., genus Alle). 



The followiuf? Families are referred to this Order in the Ameri- 

 can Ornithologi.sts' Union Checlc List : 



A. Tail-feathers wanting. (Suborder Podiciperte.'!.) 



1. Podicipidae. Anterior toes lobed, the nails very broad and flat, with rounded tips. 



B. Tail-feathers present, but short. (Suborder C'ew.'/ii.) 



2. Urinatoridae. Hind toe present. 



3. Aloidse. Hind toe absent. (Not represented in the Illinois fauna.) 



According to Seebohm,* the Afc/'dw should be removed 

 from any close association with the Podicipklcp and Urina- 

 tnrifhf-^ which that author unites in a so-called Order which 

 he terms '•'•Colymho-Podiclpmy The latter he considers as repre- 

 senting' "highly specialized Penguins," while the Alcida; he re- 

 gards as "Aix-liaic Gulls."' 



lOven the Penguins (Family Sp/irnt'sridfc) have been placed b^' 

 some authors among the I'l/t/ojjodfx, but there can be no doubt 

 as to the very great remotenoss of their relationship. 



The Ibis, October, 



