166 MR. W. K. PARKER ON STEATORNIS CARIPENSIS. [Apr. 2, 
The culmen of the rostrum in Séeatornis is subacute (Plate 
XVII. fig. 2); its dorsal outline forms an almost perfect quadrant, 
it is somewhat wavy, and drops suddenly near the hinge, which is 
straight across the skull, and is perfect. The nostrils (figs. 1, 2, e.n.) 
are in front of the middle of the rostrum, reniform, oblique, and 
6 millim. long; a small alinasal valve, covered by the ossified roof, 
forms the “ hilus”’ of the kidney-shaped opening. 
These ossified roof-cartilages (a/.n.) ave full of vascular borings, 
which give them a different appearance to the nasals and premax- 
illaries (v., px.). But the fusion (ankylosis) of these parts is 
perfect, and so also is that of the ossified septum nasi, with the 
surrounding bones. That wall has in its middle a large pyri- 
form fenestra, 4 millim. long and 3 millim. deep, a structure 
more frequent in Aquatic and Grallatorial birds than in the higher 
Arboreal types. This is one of its aberrant characters ; the inferior 
turbinal (right and left) remains unossified. Under the bulging 
alinasal tracts there is a gently concave, wide sulcus, which ends in 
an open space between the rostrum and the ectoethmoid (pars 
plana). At this part of the skull the angles of the maxillaries 
(figs. 2, 3, mz.) are 20 millim. apart ; and close here, in the hollow 
behind the descending crus of the nasal, the projecting maxillo- 
palatine (figs. 1-3, mz.p.) is seen, right and left. 
This lateral rostro-cranial space should be largely filled in by 
the lacrymal (fig. 1, /.), which is so constantly large with a con- 
siderable frontal suture, and a broad supraorbital tract, in the 
Cuculines generally. Here, however, in Steatornis, it is very small, 
and is ankylosed to the nasal, forming a small projection, 3 millim. 
in extent, to the postero-superior edge of the rostrum. This con- 
dition of things is very common in such Passeres as possess a small 
lacrymal ; in the Corvidee, Laniide, and some others it is pupi- 
form and free. 
In the Woodpecker (Gecinus viridis), and in that marvellously 
aberrant Fowl, Opisthocomus, the same thing is seen; the lacrymal 
being very small, and ankylosed to the nasal. 
The margin of the rostrum is cultrate, and the dentary edge is 
separated by a groove from the palatine face of this region; the 
middle is gently ridged, and this ridge passes into the ossified 
septum nasi (s.n.), which in its fore halfis marked off by a right and 
left chink. In its hinder half it is higher than, but ankylosed to, 
the maxillo-palatines (mzx.p.), which swell downwards, right and left, 
and have a notched hinder margin. Between these parts there is 
another sharp notch, filled in, in front, by the bony nasal septum. 
The outer notches as well as the inner are in front of the maxillary 
angles, and the whole posterior palatal margin of the rostrum is 
thus strongly serrate. 
The maxillo-palatines (fig. 3, ma.p.) are only moderately high and 
spongy ; under their thickest part the prepalatine laths ( pa.) pass 
forward and are ankylosed to them. The fibrous fore part of the 
prepalatines reaches as far forwards as the middle of the septum 
nasi; where they escape from under the maxillo-palatines they are 
