OF GALLINACEOUS BIRDS AND TINAMOUS. 201 



Rhea, Tinamus, Hemipodius, Dendrortyx, Perdix, Phasianus, Gallus, Pavo, Meleagris, 

 Oreophasis, Crax, Talegalla, Goura, Syrrhaptes, Columba, Pterocles. Here we see that the 

 Syrrhaptes (PI. XXXVIII. & PI. XLI. fig. 4) stands high in this respect, standing 

 between Goura and Columba. That, however, must be qualified by showing that whilst 

 there is, as it were, a sudden rise towards perfection of growth, yet nevertheless there 

 are deficiencies in detail that modify this anomalous sternal completeness in so low a 

 bird. I am not more surprised at finding such long-wingedness in the almost struthious 

 Syrrhaptes, than in seeing birds related to the Thrush and the Sparrow with scarcely 

 the power to fly : sudden arrest or over-development of some particular organ is not at all 

 uncommon in nature. Zoologically, the Stilt-Plover is but a somewhat absurd Dotterel ; 

 and the shanks of the Flamingo only serve him to stalk about between the stilted Cranes 

 and the clacking Geese. Were not the graduation of the sternum from the Gallinaceous 

 to the Pigeon-group very gentle, that of the Syrrhaptes might cause surprise ; but the 

 change is easily made, and the clinging of the inner hyposternal process (,P1. XLI. fig. 4) 

 to the entosternum for most of its length, and then its rejoining the mesial piece at the 

 end, is all soon done in actual nature by allowing the bony matter to creep further and 

 further along the membranous spaces between the cartilaginous bands. Tlie great 

 distance of the external fork of the hyposternum from the end of the bone is very extra- 

 ordinary in the Gailinee (PI. XLI. figs. 9 & 10) and the Pigeons. In many water-birds, 

 in Owls, Giant Goat-suckers {Podargus), in Woodpeckers, Toucans, Kingfishers, Rollers, 

 where the hyposternum is double, the outer piece comes very nearly to the same trans- 

 verse line as the xiphisternum. This is not always the case in w-ater-birds, as may be 

 well seen in Numenius arquatus ; so that the hiatus between Syrrhaptes and the Pluvia- 

 lines is somewhat filled up even as to this character. 



In the individual now under description the inner hyposternal fork of the right side 

 is as free from the body of the sternum as in Goura ; on the left side there is an 

 ossified tendinous band, which, as in the growing Pigeon, converts the notch into a 

 fenestra (PI. XLI. fig. 4, hys. xs.). That which strikes the eye at once is that neither 

 of the hyposternal forks diverge nearly so much as in the Pigeons : there is a much 

 greater tendency to that parallelism which is so marked in the Lapwing's sternum, and 

 which, having a certain amount of filling up, is tending towards the curious, oblong, 

 complete sternum of the " Gruinae." As in the Plovers, these processes of the sternum 

 of Syrrhaptes are not nearly so pedate as in the Fowls and Pigeons. The great ento- 

 sternal keel (PI. XXXVIII, es.) is quite equal to that of the Pigeon ; but it does not 

 stand forward so well as in that bird or the Plover, but falls back in a very gallinaceous 

 manner (PI. XLI. fig. 10, es.), although not so much as in the purer types. Its ante- 

 rior margin is very thick, and it suddenly thickens, as in the Plover and Curlew 

 (Numenius), not gradually as in the Pigeons and Fowls. The broadest part of the space 

 on the keel for the " pectorahs major" is scarcely 3 lines ; in the sternum of Columba 

 livia it is 4^ lines, — the two sterna being nearly of the same size, and the greatest 



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