PKOr. W. K. PAJiKEE OX ^GITHOGNATHOUS BIEDS. 297 



at the end, and /-shaped ; but they are thicker in the young and old Ileniipodius, 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, mx.p). As far as mere length 

 is concerned, this is equal to what is seen in their counterparts in the Coracomorphte 

 generally ; it is a state of embryonic simplicity. The jugal styles of the maxillary, the 

 slender jugals and quadrato-jugals of the young (fig. l,j, q.j) are all coalesced together 

 in the adult ; so that whilst in number 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 pteiygoid ; for the pterygoids clasp the hinder of these 

 swellings, and the ethmo-palatine laminae that in front. Thus the trabeculse 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 hones 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 kregular cake of bone, and has no seg- 

 mented angle answering to the " os uncinatum." 



The frontals, nasals, and nasal processes of the praemaxillaries 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. IX. — PAET V. December, 1875. 2 s 



