302 PROFESSOR W. K. PARKER ON THE 
hinder median piece, as in Podargus and Caprimulgus : when truly azygous it is called 
here the medio-palatine. j 
Now this difference does not depend upon the narrowness or breadth of the face. 
The frog-like face of Podargus yields the most perfect typical instance of the Carinate 
type of palate, whilst the delicate attenuated skull of the Sun-Bittern (Hurypyga helias) 
has its parasphenoid exposed along almost the whole extent of the palate. 
To one who is familiar with the structure of the skull and its development in the 
lower types—Fishes, Amphibia, Reptiles—this is full of meaning. The skull of the 
Ratite is rich in even Batrachian characters; and the one under consideration, that of 
Thinocorus, is being read off by me, whilst writing, in the light of that of Testudo 
greca. 
I look upon Professor Huxley’s Geranomorphz (Cranes and Rails, P. Z. 8. 1867, 
p- 457) as a great side branch of the Pluvialine stock, and not arising at any great 
height above the Tinamide ; one of them (Psophia) retains the bony superorbitals of 
the Tinamou. 
I have hunted up every type of skull, available, in this family. The one most to my 
purpose to compare with the small skull of Thinocorus was found to be that of the 
Stanley Crane (Anthropoides stanleyanus)|—a bird of stature, and of the seed of the 
giants. 
This type, next to T'hinocorus, has the palatines widest apart ; next to it comes Hury- 
pyga, and next to that the Weka Rail (Ocydromus australis). In the gigantic extinct 
Rail (Aptornis defossor, Owen) the parasphenoid is very narrow, and the palatines as 
much approximated as in the living Rallide generally. (See Trans. Zool. Soc. vol. iii. 
pl. lii. fig. 3, a paper read on January 11th, 1848, where this bird is described as Dinornis 
casuarinus, Ow.; and ibid. vol. vii., Jan. 1871, pl. xl. fig. 3, where this bird is termed 
Aptornis defossor, Ow.). 
There are two characteristics in the adult Thinocorus which separate it from the ordi- 
nary Pluvialine types (Charadriomorphe), namely :—the arrest of the basipterygoids? ; 
and the absence of the lateral occipital fontanelles—vacuities shared by the Plover with 
the Goose tribe, but absent even in the young of the Rails, and very variable in the 
Gruide. The small azygous occipital fontanelle of the Pigeon, which is variably closed- 
in in the Sand-Grouse and Hemipods, is in Thinocorus wholly unenclosed, as in the 
feebler forms of Plover—the foramen magnum being pear-shaped, and the narrow upper 
part being due to deficient chondrification in the embryo. 
In conformity with this divergence from the true Plovers, there is also the abortion 
of the inner notches on the posterior margin of the sternum. In Hurypyga they are 
almost suppressed, in the Rallide quite; whilst in the Cranes, in Psophia, and in the 
Kagu there are no distinct notches whatever, external or internal. 
In some things, as I shall show, Thinocorus approaches the Hemipods; with Quails 
1 The gift of Dr. Murie. > These are also aborted in @dicnemus and Otis. 
