MR. W. K. PARKER ON THE OSTEOLOGY OF BAL^NICEPS REX. 297 



grooves, and again thickens so much towards the rather sharp margin as to give it the 

 appearance of curving in. 



In the Boat-bill all these characters are softened and feeble : the mesial portion is, as 

 it were, pinched into a keel, convex along the mid-line and concave at its sides ; whilst 

 the grooves are wider and more open, and the sides of the jaw smooth and evenly 

 convex as they turn slightly inwards to form the sharp margin. The great upper 

 grooves are nearly obsolete in the Adjutant ; in the Heron they are well marked 

 in front of the nasal fossae, but only pass halfway to the straight tip. In the Pelican 

 they are distinct for two inches from the nasal fossje, when they lose themselves in the 

 large cellular scoopings that occupy so much of the interspace between the moderately 

 convex ridge and the margin ; yet the upper margins are indicated all the way by a 

 row, on each side, of large oval vascular apertures, and again become distinct as they 

 form the boundaries of the beaked tip of the bill. In the Spocnbill these upper pre- 

 maxiliary grooves are very distinct : diverging as they pass out from each nasal fossa, 

 they run within one-tenth of an inch of the margin in the narrow part, and one-eighth 

 in the broad spatulate end, round which they pass to become confluent above, a little 

 posterior to the broad and gently curved tip. The large concave ' hard palate ' of the 

 Balaeniceps is not a whit less elegant than the upper and lateral aspects of tlie jaw — 

 indeed more so, if possible ; the vascular grooves being here very perfect, as they pass 

 out at right angles to the great mesial sinus, forking and inosculating laterally like the 

 veins of a beautiful leaf. 



To the distance of 1^ inch from the tip, the mesial line below is keeled, at first rather 

 sharply, but the ridge soon becomes convex, and widening as it passes backwards, is 

 in reality continued along the greater part of the palate ; but at the distance above- 

 mentioned it is laid open — no longer a ridge, but a large vascular sinus. 



For more than the anterior half this groove is sharply margined, and, besides the 

 vascular openings into the lateral dendritic grooves, exhibits large open spaces which 

 communicate with the rich diploe occupying the thick mesial ridge of the jaw. The 

 margins then become smoother and more rounded, and the groove widens as it passes 

 backwards to descend rather suddenly to the posterior boundary of the hard palate. 



Turhinals or Ethmoidal Pterapophyses\ (PI. LXV. fig. 7, t h.) 



From the inner part of the articulation of the palatine with the pre-maxillary there is, 

 on each side, a smooth convex ridge, which runs forwards for above an inch, slightly 

 converging towards its fellow. A little behind where these ridges lose themselves in 

 the surrounding bone there is an irregular opening about two lines in length, wliich opens 

 from the mesial groove obliquely into the space above. Behind this tiiere are several 

 smaller passages scarcely true to the mid-line. These openings are all of them the 

 remains of a membranous space, which is large in many birds, and lies in front of and 



' We have adopted this term provisionally ; Professor Gcodsir would have us believe that these elements are 

 neurapophyses (see cyp. cit. p. 144), 



