OF GALLINACEOUS BIRDS AND TINAMOUS. 233 



pterygoid" (in Fish and, as I find very constant, in Birds) I substitute " meso- 

 pterygoid," as it is not the homologue of the internal pterygoid plate of Man and 

 the Mammalia generally, but occurs in the Fox and some others in addition to the 

 internal or true pterygoid. Again, the term " ectopterygoid " would seem to infer that 

 it was the homologue of the external pterygoid plate, which it is not ; it only occurs in 

 the " Sauropsida :" Cuvier's term " os transversum " must be retained for the present. 

 The small membrane- bones which, in the " Lamellirostral" birds and in the Tiger Bittern, 

 pass inwards and forwards from the inner edge of the palatines at their middle, may be 

 called " interpalatines :" they occur exogenously in the palatines of many arboreal birds. 

 Instead of using the heavy terms " ecto-" and " ento-pterapophysis " for the processes 

 which, often in the Mammalia and constantly in birds, arise from the basisphenoid, 

 and which have no anthropotomical name, these had better be called posterior and 

 anterior pterygoid processes. In Man these have no existence ; for the " lingulse sphe- 

 noidales " (the rudiments, as Professor Huxley suggested to me, of my " basitemporals " 

 in the " Sauropsida ") apply themselves closely to the body of the sphenoid behind. In 

 many Mammals these ossicles are thrust outwards to some distance from the axis of the 

 skull by a pair of small posterior pterygoid processes ; in the Hedgehog these parts are 

 very large. In most Mammals the internal pterygoid plate abuts against the body of 

 the sphenoid ; but in the Guineapig {Cavia aperea) a pair of pedicles keep them ofi", 

 and to them they are eventually anchylosed : these ai'e a retention of the ornithic 

 " anterior pterygoid processes " — the " entopterapophyses " of my former paper. 



These processes attain their largest size in the " Struthionidas " (PI. XLII. fig. 1 , apt.), 

 are aborted in many genera, and do not exist in the Reptiha ; for in them the pterygoids 

 are attached to the skull-base still further backwards than in the Ostriches, through the 

 medium of the pterygoid processes of the basitemporals ; these latter processes are well 

 seen in the King- Vulture (Sarcorhamphus papa) , but in it they are only used for muscular 

 attachment. 



I have in this paper used the term " prevomer " for the splint bone which is vicarious 

 of the maxillary in the Bird-class : it is not (as Cuvier supposed) the homologue of the 

 " inferior turbinal " of Man. 



At p. 285 of my former paper, the Oyster-catcher {Hcematopus) is placed in " Group 3," 

 instead of in " Group 5," as though it had its anterior pterygoid processes aborted : this 

 is not the case. The " turbinals or ethmoidal pterapophyses," spoken of at p. 297, are 

 really the inner parts of the prevomer and the " maxillaries ;" at p. 301 , the outer margins 

 of these bones. 



At p. 317, in a note, the tympanic is spoken of as being absent from the skulls of 

 most " Gallinacese :" this only refers to the meatus-bone, so large in the Peacock. I 

 had not then discovered the proper tympanic chain of ossicles. 



At p. 317 I failed to mention that the small tongue of the Balwniceps showed its 

 near relationship to the Ibis. When the whole of the ardeine " Altrices " have been 



2h2 



