OF GALLINACEOUS BIRDS AND TINAMOUS. 183 



still separate from the rest. The vertebral column in the two species has the numbers 

 in each region as follows : — 



Cervical. Dorsal. Sacral. Caudal. Total. 



Hemipodius varius 15 4 13 6 38 



Hemipodius ? 15 5 13 6 39 



As usual, the last vertebra is an anchylosed series, so that the real number is perhaps 

 about forty-five in all. 



Perhaps the atlas, from its relation to the basis cranii, is the most interesting vertebra 

 in the entire column ; at any rate it is a good measure of the height of a bird in the 

 ornithic scale. The perfectly typical character of the occipital condyle of Hemipodius 

 (so unexpectedly combined with a typical but somewhat arrested vomer) is repeated 

 in the articular " cup " of the atlas. A few remarks, however, upon the modifications 

 of this part in relation to the more or less reptilian character of the occipital condyle — 

 that is, whether its longest diameter is crosswise, and its shape bifid, as in the Fowls, 

 or whether its longest diameter is lengthwise, and its surface entire, as in the Crows — 

 ■will be useful. Most of the " Zygodactyli " agree with the Crows (Corvus, Gymnorhina), 

 with the Finches {Fringilla, Pyrrhula), and with the soft-billed Songsters (Budytes, 

 Pratinola, Motacilla) in the typically ornithic character of the occipital condyle and 

 of the atlantal " cup." But the " Musophagidse " (e.g. Corythaix bufoni) agree with 

 the " Cracidse," and therefore with the other Gallinse in the possession of a very 

 imperfect cup to the atlas. 



The arboreal Pigeons, the Plovers, the Ostriches, the Tinamous, the Sandgrouse, the 

 Psophise, the Ardeinse, and most of the Palmipeds agree in this non-typical character of 

 the cup of the atlas. Amongst the Palmipeds having this character, I may mention 

 Querquedula and the other Anatinse, the Larinse (e.g. Larus, Gavia), the Divers (e.g. 

 Colymbus and Uria) ; yet in Alca tarda the odontoid ligament is bridged over, but still 

 more so in the Cormorant {Phalacrocorax carlo). On the other hand, the Owls and 

 Hawks are almost as far from the typical birds as the Fowl-tribe ; this, however, agrees 

 perfectly with many other non-typical characters in these " Raptores." I do not 

 consider them to be much higher in the bird-scale than those other " unclean " birds the 

 Storks and the Cormorants. Occasionally the cup, although very incomplete, is slightly 

 bridged over by bone ; this occurs in the Lapwing (Vanellus cristatus). 



As to the other cervical vertebrae of Hemipodius, there are no carotid "bridges" 

 (PI. XXXV. fig. 5, c.) perfect, as is also the case in Fowls, Pigeons, and Plovers ; and 

 there are no especial characters to distinguish them from the smaller GaUinaceous birds. 

 The last two bear ribs — the small one a mere style, and that on the last two-thirds the 

 size of the dorsal ribs. This rib bears a considerable " appendage." The tenth to the 

 fourteenth cervicals (inclusive) have distinct, flat, sharp " hypo-parapophyses ;" in the 

 fifteenth there are three such processes. These processes are long on the first two 

 dorsals ; the first of these strongly bifurcate, the rest feebly so. None of the dorsals 



VOL. V. PART III. 2 B 



