OF GALLINACEOUS BIRDS AND TINAMOUS. 203 



The body of the Stilt-Plover is only about half the bulk and weight of that of Syrrhaptes, 

 and yet the tibia is as five to two in length, whilst the tarso-metatarse is 55^ lines long, 

 that of Syrrhaptes being only 10 lines— more than five and a half times the length. 



Even with the Pigeon the comparison shows how rapidly the more distal segments 

 have shortened ; for, the thigh-bones being in both cases 1^ inch in length, the tibia is 

 3 lines shorter in the Syrrhaptes, the tarsus 4 lines ; and the mid toe is only half the 

 length of that of the Pigeon (PI. XXXVIII./., dg.). In the Ptarmigan, as in the Galling 

 generally, the thigh-bone is relatively longer. In the Guatemala Tree-Partridge {Ben- 

 drortyx), a bird intermediate in size and bulk between the Grey Partridge and the Quail, 

 the OS femoris is 2 inches 3 lines long, or three-quarters of an inch longer than that of 

 the Syrrhaptes. In the Plovers generally the thigh-bone is relatively short ; in Vanellus 

 cristatus it is exactly the same length as that of the Common Pigeon and Pallas's Sand- 

 grouse (Syrrhaptes). The os femoris, like the rest of the leg-bones, is non-pneumatic in 

 the Syrrhaptes, and is slightly more arched than that of the Pigeon and Lapwing, but 

 not so much so as in the Fowls : the arching of the femur of Dendrortyx is as perfect 

 and as elegant as in the human thigh-bone. The splint-like fibula (/6.) runs along three- 

 fifths of the tibia [th.), and the latter bone does not send so strong a crest out laterally for 

 its attachment as in the Pigeons. The muscular crests on the head of the tibia are in 

 an arrested state, and are curiously contrasted with those of the tibiae of its congeners, 

 even of the Pigeon. 



There is, however, a bony bridge in front of the inferior condyle, and the whole bone 

 has about the same amount of arcuation as that of thePigeon. The whole posterior surface 

 of that condyle rolls on a two-faced, very large calcaneal ossicle (PI .XXXVIII. cl.), which 

 has a smaller one perched on it. The tooth on the middle of the astragular portion of the 

 tarso-metatarse in front (PI. XLI. fig. 6) is smaller than in the Pigeon ; and the head of 

 the posterior or middle metatarsal does not project so much behind (XLI. fig. 7), and alto- 

 gether this curious little bone is free from those ridges and fossse which mark a well- 

 developed tarsus. The three hinges (PI. XLI. figs. 6 & 7) (there is no trace of that for 

 the hallux) have, like the lower head of the tibia, each its strong sesamoid, and there are 

 smaller sesamoids at the base of the ungual phalanges, one for each. The toe-bones 

 (PI. XXXVIII. dg.) remind me of those of the Mole ; they are very short and stout, and 

 there is one joint wanting in each outer toe. There is, as Plate XXXVIII. dg. & 

 Plate XLI. fig. 8 show, a curiously sprawling condition of the toes, the outer two being 

 turned outwards, whilst the inner is turned inwards. The last phalanx is always deeply 

 grooved on both sides, and it is covered by a very strong nail, whilst the under surface 

 of the foot — the only part not buried in feathers — is paved with very strong projecting 

 tubercles (PI. XLI. fig. 8.). The toes are so close together that the sole of the foot forms 

 one slightly trilobate mass, with the tubercles somewhat obsolete below the setting-in of 

 the toes. The sprawling condition of the toes is thoroughly reptilian, and is seen to a 

 less extent in the Ptarmigan (Lagopus). 



