SKULL OF THE AGITHOGNATHOUS BIRDS. 267 
able character, the possession of distinct palatine plates in the maxillary region, in 
addition to the maxillo-palatine processes, is most important; for these bones, in a 
descending survey, are not found until we reach the Batrachians and Ganoid fishes. I 
am speaking of forms still existent ; they may turn up in fossil Reptilia. 
Then we have just seen that in Central and South America certain tenuirostral and 
the feebler of the conirostral types have these bones (Mniotiltide and their allies on 
the one hand, and Tanagride on the other). However near or far off these types may 
lie in their relation to each other, the existence of any one marked character in 
the species of families belonging to a continuous geographical territory indicates a 
common root or cause. In an unnamed species of Jcterus I find such a similarity of 
the whole skull and face to that of a Starling, on one hand, and of the Cardinal and the 
Buntings on the other, that I am at a loss to characterize it otherwise than by saying 
that it is an intermediate type. Yet on the whole, with a narrower face and a broader 
and a more capacious cranium, it has altogether a stronger structure than that of any 
of these birds. 
The straight pterygoids are quite normal both in possessing a moderate epipterygoid 
hook and in giving off a mesopterygoid segment. The transpalatine is spongy and 
angular, and the whole of that region is steep. Stout to the fore end, the palatines lose 
themselves in the solid, decurved, high-backed rostrum (Plate XLIX. figs. 1 & 4, pr.pa). 
The interpalatine spurs (7.pa) are not large, nor are the ethmo-palatine coils much 
extended (e.pa). The palato-maxillaries (p.ma) are somewhat ankylosed to the pre- 
palatal bars; but their middle is opposite the dentary angle of the premavillaries, so 
that they are thus excluded from that category, and seem to belong to the outworks of 
the palatine arch. 
The yomer (v) is broad in front, and has very converging crura, which are 
ankylosed to the ethmo-palatines. Between each shoulder and the pedicle of 
the maxillo-palatine there is a solid subcentral septo-maxillary (s.ma); and also on 
the inturned part of the nasal floor (x. f) there are two more ossicles on each side, 
besides lesser bones. The septum nasi (s. 2), which is alate, is ossified considerably ; it 
is strongly ribbed. The alinasal and inferior turbinals are soft ; the former are not seen 
from below, on account of the great development of the nasal floor. The delicately 
pedunculate maxillo-palatines end in a large, flat, cultrate blade, with sharply produced 
points, giving it a falcate character; the inner edge of this scythe is serrate. The 
lacrymal, like that of Sturned/a (fig. 4, 1), is long and pupiform, and has the form and 
position seen in Pipra, Phytotoma, Tanagra, and the larger Crows. At its base 
it has a large, distinct, ovoidal os uncinatum(o. ~). The general ecto-ethmoidal mass 
projects outwards less than in the Passerine types generally. ‘The alinasal region 
is soft. 
VOL. X.—Part vi. No. 3.—June 1st, 1878. 2P 
