frontal and nasal, while the rather lar,i;er clescencUn<;- portion of 

 the bone is plate-like, being transversely compressed, and does 

 not reach the maxillary below. At its apex it supports a spicu- 

 liform OS uncinatum, as we find in the Urinatoridas. 



The foramen magnum is large, looks almost directly back- 

 wards, and is of an acute cordate outline, with the apex above. 

 The occipital condyle is well developed, completely sessile, and 

 barely notched superiorly. Passing to the basitemporal area we 

 find it somewhat contracted, nearly level and smooth, w^hile its 

 anterior apex underlapping the double entrance to the Eusta- 

 chian tubes. There are no evidences whatever of basipterygoid 

 processes, and the long, straight pterygoids stand well awa)- 

 from the sphenoid. One of these bones has cultrate inner and 

 outer edges or borders, and is peculiar in the way it articulates 

 with the quadrate. The latter bone throws out a well devel- 

 oped apophysis, mesially, the summit of which is rounded to be 

 received into the articular cup existing on the posterior end of 

 the pterygoid. In most birds the pterygoids articulate upon the 

 inferomesial border of the os quadratum. These bones in the 

 ^rebe hardly touch each other anteriorly, where their palatine 

 heads are to some extent expanded. The sphenoidal rostrum is 

 comparatively slender and is carried to a sharp apex in front. 

 The palatines have their postero-external angles completcl) 

 rounded off, while their lower inner and outer margins are 

 moderately bent downwards,— the inner one rather abruptly so. 

 When articulated tn sUu these bones are in contact with each 

 other all along beneath the rostrum. The antero-mesial portion 

 of the post-palatine part of the bone, curls upwards and inwards 

 towards the mesethmoid, and in front its mesial process runs 

 forward as a long slender spine for the accommodation of the 

 vomer. The prepalatine portion of a palatine is long, narrow 

 and vertically compress d. Extending a long ways to the front 

 rapidly tapering to a point as it does so, the prepalatine under- 

 laps the maxillary and maxillo-palatine, and passes along close 

 to the mner aspect of the dentary part of the premaxillary, 

 being thoroughly fused there in the adult. The suture, how- 

 ever, remams visible throughout life. For the size of the bird 

 Holboell's grebe has one of the longest vomers at present 



