SKULL OF THE £GITHOGNATHOUS BIRDS. 303 
it has the remotest relationship ; it eliminates itself from the typical Pluvialines or 
Charadriomorphe ; and there is no place for it, save within the bounds of Professor 
Huxley’s group the “‘ Geranomorphe,” 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)! like 
Thinocorus. 
The occipital condyle (Plate LIV. fig. 1, oc. ¢) is somewhat ovoidal, the antero-poste- 
rior diameter being slightly longer than the transverse, unlike that of the Crane (fig. 6, 
oc. ¢), 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 (4.¢) sends an ear-shaped process round each “internal carotid” (7.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.¢.7). 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 (0.yg), 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 trabecule, which run backwards, embracing 
the whole lateral pituitary region (see ‘ Fowl’s Skull,’ pl. Ixxxii. figs. 1-3, /y). The 
massive beam which the parasphenoid and coalesced trabecule together form beneath 
the interorbital septum in Struthio camelus (see ‘ Ostrich’s Skull,’ pls. 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, pa.s) outrivalled; and the foremost undersetter, the vomer (v), 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- 
branipora), 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, 
‘ [ have not yet 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. 
