OF GALLINACEOUS BIRDS AND TINAMOUS. 227 



shaped, and having short curved rami ; it has, however, no angular process : there is a 

 slight trace of this process in the Syrrhaptes, and it has become still more evident in the 

 Plovers (Vanellus and Charadrius) and in the Gambet {Totanus fuscus) and its alhes. 

 Yet the feebler sort of pluvialines have this same kind of furculum, which is but little 

 altered in the typical Ibises : it takes on great changes in the forms that grow, as it 

 were, out of the Ibis-type, and that have become specialized into Herons and Storks. 



The curve of the furcular rami in the Tinamou is shown by the fact that they are one- 

 third longer actually than a line drawn from the tip to the angle. The flattened tip of 

 the bone is as blunt as in Syrrhaptes, and blunter than in the Lapwing : in the feeble 

 " Longirostres," e. g. Totanus, Limosa, and also in Numenius, the extremity is greatly 

 lengthened. I mention this to show that the furculum of the Tinamou comes nearest 

 to that of the simple pluvialine type. In the " Gallinae and Rallinse " we have a 

 V-shaped furculum, in the former with an angular plate, in the latter without it : in 

 the Hemipodius we get much nearer the Fowls in this part of the skeleton. The 

 coracoids (Pis. XXXIX. & XLI. cr.) are very galhnaceous in character, being roughly 

 formed, having none of the sharpness and neatness of the bone in the higher tribes ; 

 they are much shorter than in the Fowl, as may be seen from the table ; their pneu- 

 matic hole is close behind the head. 



The sternum of the Tinamou was described and figured by M. F. J. I'Herminier in 

 1827. He describes it at p. 66 of his ' Recherches sur I'Appareil sternal des Oiseaux ;' 

 and in pi. 3. fig. 24, a, b, an upper and an oblique side-view are figured of this remark- 

 able structure. At p. 67 he remarks, " Cette pi^ce existe seule au Museum, et manque 

 de son complement par I'absence des trois os de I'^paule ; elle m'a sufB cependant pour 

 s^parer les Tinamous des Gallinaces, auxquels on les reunit d'ordinaire, et pour en 

 former une famille tout-^-fait distincte." 



We shall see, even from the structure of the sternum only (Pis. XXXIX. & XLI. 

 fig. 1), how distinct the Tinamou is from the Fowls ; and this bone also throws some 

 light upon this extremely variable part of the skeleton — the worst part for the systematist 

 to hold by, and yet extremely valuable if properly checked by the structure of the 

 skeleton as a whole. The sternum of the Tinamou is a good halfway in passing from 

 that of the Apteryx to that of the Fowl ; and although the Tinamou has not escaped 

 from the struthious group, yet, in brief, it may be said to be a natural intermedium 

 between those forms. The only process in the Tinamou's sternum which is wanting in 

 that of the Apteryx is the keel ; but there is a marvellous contrast in this respect : that 

 of the Tinamou is large, long, and rather deep ; the whole body of the sternum in the 

 Apteryx is like a strip of parchment. We have convexity in the breastplates of the 

 Emu, Cassowary, and Ostrich, the mesial part being as it were collected into an 

 ovoidal tumulus : in the Rhea the entosternum is really subcultrate. The episternum of 

 the Tinamou (PI. XLI. fig. 1, ep.) has all the appearance of that of a Fowl from 

 which has been smoothly pared the whole of the middle bridge and lower keel ; or it 



