SKULL OF THE ^GITHOGNATHOUS BIRDS. 303 



it has the remotest relationship ; it eliminates itself from the typical Pluvialines or 

 Charadriomorphee ; and there is no place for it, save within the bounds of Professor 

 Huxley's group the " Geranomorphse," wisely made sufficiently elastic to embrace the 

 Cranes and the Rails. If the characters given of that group do not wholly correspond 

 to, or are not general enough to embrace this type, they must be modified so as to be 

 fit to receive this new subfamily ; for this is a type quite distinct and special as com- 

 pared with the other Geranomorphs, and as worthy of family leadership as the Rail, 

 which has so many living congeners, and does not stand alone (or nearly alone) i like 

 Thinocorus. 



The occipital condyle (Plate LIV. fig. 1, oc. c) is somewhat ovoidal, the antero-poste- 

 rior diameter being slightly longer than the transverse, unlike that of the Crane (fio-. 6, 

 oc. c), which is transversely bilobate, as in Fowls and Geese ; Thinocorus here agrees 

 with the Tinamou, the Hemipod, and the Plover. The broad two-lipped basitemporal 

 plate {b.t) sends an ear-shaped process round each " internal carotid " (?'. c) ; these 

 processes extend a little further outwards than the tympanic wings of .the basisphenoid 

 above, which wings form the trumpet-shaped anterior tympanic recesses {a. t. r). At 

 the mid line the basisphenoid is scooped for the opening of the Eustachian tubes ; and 

 between this fossa and the outer wing the bone sends out a slightly winged ridge, the 

 only remnant of the basipterygoid processes (b.pg), the absence of which, in the adult, 

 suggests that this bird belongs to the Gruines and not to the Pluvialines proper ; this 

 is in strong and sharp contrast with those characters in it which, without controversy, 

 are essentially Struthious. These marginal wings and the submarginal ridges were, 

 at first, modelled on the apices of the trabeculae, which run backwards, embracing 

 the whole lateral pituitary region (see ' Fowl's Skull,' pi. Ixxxii. figs. 1-3, fg). The 

 massive beam which the parasphenoid and coalesced trabeculae together form beneath 

 the interorbital septum in Struthio camelus (see ' Ostrich's Skull,' pis. viii. «& ix. figs. 2 & 

 10, but still better seen in the adult skull, see Huxley, P. Z. S. 1867, p. 420, fig. 1) is 

 here (figs. 1 & 2,i)a.s) outrivaUed; and the foremost undersetter, the vomer («), has the 

 same relative expansion and size. The parasphenoid is truly azygous (with symmetrical 

 detached " basitemporal " wings behind) ; but the vomer was two broadish splints at 

 first. I have drawn it from three individuals (figs. 1-3, v) ; and as the parasphenoid 

 is a spongy pneumatic mass, so also does the vomer become a collection of bony 

 air-cells. 



In fig. 2, evidently the oldest individual, and having the largest vomer, this bone has 

 a quaint but real resemblance to four chambers of a flat Polyzoon {Lepralia or Mem- 

 Iranvpora), having two pairs of air-passages beneath — a pair on each side of the obtuse 

 median keel. Behind, the bone displays its primary symmetry by sending backwards a 

 pair of thin bluntly triangular flaps, the outer margin being notched, where they begin, 



' I have not j-et had an opportunity of studying the osteology of Attagis, which, Mr. Salvin informs me, is 

 its nearest congener ; see, however. Prof. Garrod's paper on this type, above referred to. 



