706 SYSTEMA TIC SYNOPSIS. — COL UMBuE — PERISTER^. 



afford ordinal characters; but the rectrices are usually 12 or 14 instead of the higher numbers 

 usual in gallinaceous birds, but run up to ]6 in Goura and some species of Phaps, even to 20 in 

 Otidiphaps ; and the wings are usually long and tlat, not short and vaulted. Plumage desti- 

 tute of aftershafts (qu. Didus f). Syrinx with one pair of intrinsic muscles and asymmetrical 

 extrinsic muscles. Oil-gland nude, when present (small in Treron, etc. ; wanting in Goura, 

 Starncenas) ; gall-bladder generally absent (present exceptionally in some true Pigeons) ; 

 coeca absent, or present, but small ; two carotids ; gizzard muscular, sometimes in part horny 

 or even osseous ; a well-developed oesophageal crop ; intestine varying from very short to ex- 

 tremely long (7 feet long in Didunculus !). There are many good osteological characters; 

 palate schizognathous ; nasal bones schizorhinal ; basipterygoids present (except in Didus) ; 

 sternum doubly notched, or notched and fenestrate, on each side ; pectoral ridge of humerus 

 salient and acute, and does not receive the insertion of the 2d pectoral muscle ; ambiens nor- 

 mally present, the birds being unquestionably homalogonatous, but sometimes lost ; femoro- 

 caudal, accessory femoro-caudal, semitendinosus, and accessory semitendinosus present ; the 

 fourth glutseal muscle, which in other schizorhinal birds covers the femur-head, is undeveloped 

 (Garrod). 



Some ornithologists, like Liljeborg, enlarge the Columbine order, under name of Pullas- 

 tra, to receive the American Curassows (Cracida — see beyond) and Old World Big-feet, or 

 Mound-birds {Megcqwdidce) ; mainly on account, it would appear, of the low position of the 

 hallux in these families. But the balance of characters favors their reference to the gallina- 

 ceous series, where they are relegated by Huxley. While there is no question that Columbine 

 birds are very closely related to Galline, in fact inosculating therewith, it seems best to draw 

 the line, if one must be drawn, so as to leave the CracidcE and 31egapodidce with Gallince. 



The Sand-grouse (better Sand-})igeons), or Pterodetes, represent the inosculation of the 

 two series. They are terrestrial Columbines, modified for a grouse-like life ; the digestive sys- 

 tem is fowl-like (coeca several inches long, etc.) ; but the pterylosis, the sternum and humerus, 

 the cranial and many other characters, are pigeon-like. The skull is schizognathous and 

 holorhinal, with basipterygoids ; cervical vertel)rfe 15 or IG. The ambiens and other classifi- 

 catory muscles of the legs (A B X Y) are present, together with the biceps slip and expansor 

 of the secondaries. The intrinsic syringeal muscles are highly developed. There are two 

 carotids, a nude oil-gland, and gall-bladder. The plumage is aftershafted, and covers the feet 

 to the claws ; the wings are aquintocubital. The young hatch downy. Of the two genera, 

 Pterocles is 4-toed, Syrrhap)tes 3-toed. The only alternative to reference of Pterodetes to the 

 Columbine series is their elevation to independent ordinal rank, as proposed by Huxley, and 

 as now generally agreed upon by ornithologists. I accordingly modify some expressions used 

 in former editions of the Key, in order to characterize the Columbce more strictly, by exclu- 

 sion of Pterodetes therefrom. 



The Columhce, as above indicated, are exactly conformable to Huxley's Peristeromorphce. 

 Assuming the imperfectly known extinct Dodo, Didus ineptiis, and such of its kindred as the 

 Solitaire, Pezophaps solitarius, to have been modified Columbines, the order may be separated 

 into two suborders, Diui and Perister.e. The Peristerce alone are American. 



Suborder PERISTERiE : True Columbine Birds. 



(Equivalent to Coliimhce proper of most authors, Peristeromorphce of Huxley; Gemitores 

 of Macgillivray, or Gyraiites of Bona])arte plus Didunculus ; Columbce of Garrod minus Ptero- 

 detes ; Pullastrce of Liljeborg minus CracidcB and Megnpodidcc.) Skull schizognathous, 

 schizorhinal ; basipterygoids prominent (they are absent from Dldi) ; angle of mandible not 

 produced but abruptly truncate ; rostrum externally as abovesaid. Dorsal vertebrje hetero- 

 coelous. Sternum double-notched, or notched and fenestrate, on each side, rarely single-notched 



