No. 1.] NORTH AMERICAN PASSERES. 99 
this latter character it does not agree with the Shrike. Turning 
to Lanzus, we meet with a skull wherein all the anterior part of 
the rhinal chamber is more or less completely filled in with osse- 
ous tissue of the cancellous variety; and this so far fills up each 
external narial opening that there is left on the side of the supe- 
rior mandible only two small apertures, an anterior subelliptical 
one, and a posterior vertico-elongated one, just in front of the 
nasal bone. Where this filling appears externally, it is covered 
over by a layer of compact bone which is continuous with the 
outer superficies of the premaxillary and nasals. (See Figs. 100 
and 104 of my memoir on the Osteology of Lanzus.) 
The vomer is strictly passerine in this Shrike, but the maxz//o- 
palatines are comparatively broad processes and entirely lack the 
mesial bulbous free extremities, present in Vzveo and nearly all 
passerine birds. 
Lantus has the zuner posterior angles of its palatines drawn 
out into conspicuous spine-like processes, and the anterior limb 
of either of these bones is broad and flat, especially where each 
merges into the premaxillary. 
In all old specimens of these Shrikes that I have ever exam- 
ined, the palatine ends of the pzerygords fuse completely each 
one with a palatine on its own side, —a very unusual condition,} 
and one never found to obtain in Vireo. 
Finally, the interorbital septum is far more complete as a rule 
in Skrikes than it ever is in the Vireos, in which latter it agrees 
precisely with the Warblers. 
The mandible of Lantus is far more powerfully constructed 
than we find it to be among the vast majority of Passeres, a con- 
dition we would very naturally look to be the case. 
Speaking strictly from osteological premises, I am of the opin- 
ion that Zazzus is far more closely affined with the Clamatorial 
birds than it is with Vzveo ; by this I mean that the Vireos are 
well within the passerine circle, while Lanzus, also wzthin the 
passerine circle, is close up to its limiting arc, while immediately 
over this bounding periphery we find the Clamatores, with all 
their allies, so many of which in other parts of the world possess 
strong passerine characters in their economy. Compare, for 
1 So firm is this fusion in some skulls that I once macerated a specimen for over 
six weeks, and yet the pterygoids still remained firmly attached to the palatines, even 
all sutural traces having completely disappeared. 
