PEOP. W. K. PAEKEE ON ^GITHOGNATHOUS BIEDS. 341 



Example 27. Chasmorhynchus nudicollis (the Naked-throated Bell-bird). 



Habitat. Brazil. Group " Tracheophonae," Miiller ; family " Cotingidae." 



It would seem as though the " embryon atoms" of three diverse types had striven for 

 mastery here : the Hemipod, the Goatsucker, and the Crow were put into the " limbeck ;" 

 the spirit that arose was the " Bell-bird." 



The skull of this loud-voiced caprimulgine Crow is modified from the ordinary 

 coracomorphous type far more than the skeleton generally ; this is' often the case in 

 birds. 



As far as the skull is concerned, this type has the same (but no more) right to be 

 considered one of the " Coracomorphae " as the Swift {Cypselus). In some respects it is 

 truer to the Fissirostral type than the Swift itself; indeed, in the general texture of the 

 skull, which is most exquisitely cellular and light, it comes close to Caprimulgus ; whilst 

 Cypselus has a thin fibrous skull, much more so than its passerine relatives the Swal- 

 lows. Here, then, is a point on the great Coracomorphous circle which impinges on the 

 circle containing the Frog-faced Podargus, the Oil-bird (Steatornis), and the Goat- 

 sucker ; which latter forms the touching-point. 



Still the tracheophonous Swift goes far away from the passerines, even those nearest 

 to it, the Swallows, in all the structures behind the occiput. One of the lesser of the 

 true Corvidae, the Jay, being of the same size as the Bell-bird, is good for comparison ; 

 then let the student provide himself with the skull of a Goatsucker {Caprimulgus 

 europceus) and of a Hemipod, and he will be able to follow the writer. Moreover our 

 task, though asking delicate discrimination and familiarity with the bony framework of 

 many birds, is yet a very easy one compared with that of tracing the atavistic germs of 

 a Darwinian " Pangenesis." I may remark here, how smoothly the bone-surface has been 

 polished and almost enamelled ! the walls also being of the thinnest periosteal bone, 

 and the diploe reduced to the uttermost degree of delicacy. The elegant two-winged 

 basitemporal region (PI. LXII. fig. 5, b.t) is everywhere completely welded to the sur- 

 rounding parts, save in front, where the Eustachian openings {eu) are merely separated 

 by a little wall of bone. Here the basitemporal lip is free ; it is thick and spongy, like 

 a stonecrop leaf. 



The parasphenoid (pa.s) has spread abroad beneath the true posterior sphenoidal 

 region, behind, facing most of the floor and sides of the " anterior tympanic recess," in 

 which it is helped by the thoroughly continuous basitemporals. Like a true corvine, 

 this bird has no basipterygoid processes, and the beam or rostrum runs forwards — thick, 

 rounded, and solid — to the nearly perfect cranio-facial hinge. It is imderfloored, all 

 but its hinder part, by the palatine bones, as in Caprimulgus. The true nasal septum 

 is ossified all along and directly in front of the hinge, in the middle ; and in front the 

 bony matter creeps down into the depth of the septum (fig. 7, s.n). Behind and below, a 

 small tract of the septum is ossified (figs. 5 & 8, tr) ; this is the trabecular bone (belong- 

 ing to the first facial arch) ; in front of it are two smaller bones, not united to the 



