PROF. W. K. PARKER ON 2GITHOGNATHOUS BIRDS. 297 
at the end, and f-shaped; but they are thicker in the young and old Hemipodius, are 
bowed outwards, and have a process at the base: this is most marked in the adult; it is 
pedate, its broad end looking to that of its fellow (fig. 9, ma.p). As far as mere length 
is concerned, this is equal to what is seen in their counterparts in the Coracomorphe 
generally ; it is a state of embryonic simplicity. The jugal styles of the maxillary, the 
slender jugals and quadrato-jugals of the young (fig. 1, j, g,/) are all coalesced together 
in the adult; so that whilst in nwmber the bones conform to the Galline and Pluvialine 
types, in condition they approach the Passerines. 
The same two-facedness is shown in the great tripartite ethmoid, which I will de- 
scribe in the adult first, and then give the details of the nasal labyrinth in the young. 
Behind the very complete craniofacial “hinge” the trabecular base of the middle 
ethmoid is greatly swollen into an anterior and posterior mass, with a vertical sulcus 
between, a little in front of the pterygoid; for the pterygoids clasp the hinder of these 
swellings, and the ethmo-palatine lamine that in front. Thus the trabecule give off 
a short pair of conjugationals as they converge towards their long and complete com- 
missure ; and then the two arches cling to each other by the reconsolidated mesoptery- 
goids and the ethmo-palatines, the trabecular bar swelling towards them. But there is 
no “os uncinatum,” and the conjugational process of the palatine (ethmo-palatine) clasps 
the splint, or parasphenoid, and the united trabecular bar. 
The median ethmoid is continuous with the lateral masses, or “‘ ecto-ethmoids ;” and 
these have become spongy bones in another sense than their counterparts the upper and 
middle turbinals of Man. In us they infold themselves to give room for the olfactory 
mucous membrane; in the Hemipod they, by swelling into bony tubercles, exclude the 
olfactory tract (figs. 10 & 11, e.eth). This is seen in a lesser degree in Pigeons (espe- 
cially the Dodo), in the Sandgrouse, and the Plovers; but the Hemipod has only one 
rival in this character, namely the Bell-bird (Chasmorhynchus), which I shall describe 
anon. The antorbital mass (p.p) is a rounded irregular cake of bone, and has no seg- 
mented angle answering to the “ os uncinatum.” 
The frontals, nasals, and nasal processes of the premaxillaries largely enroof the 
ethmoid, which, however, appears at the eave of the large orbit in front. That appa- 
rent subdivision into an antorbital and lachrymal, as described and lettered in my former 
paper, is a mistake, caused by my using analogy for my guide; there is no lacrymal; 
and in this respect the Hemipod differs from Plovers and Pigeons. In my former 
paper (p. 195) I supposed a lachrymal in Syrrhaptes; but it seems to be as apocryphal 
as in Hemipodius. In the great Crow-group, only the largest kinds have even a very 
secondary fore-wedged pupiform lacrymal; in most it is either absent or extremely 
small. 
The nasal labyrinth of Hemipodius is neither struthious nor coracomorphic, nor does 
it correspond with what is seen in birds near its own ornithic level; it is a stepping- 
stone from the simplicity of these parts in the reptiles to their elegant labyrinthic con- 
VOL. 1X.—PART v. December, 1875. 258 
