WEALDEN CROCODILES. 533 



Tlie ' pterygo-maxillary vacuity '^ is large, and is bounded, as in Lizards (PI. 60, 

 figs. 6 and 7, y), by the pterygoid (24), the ectopterygoid (2.1), the palatine (20), and, in most 

 genera, Ic/uana, e. g., by the maxillary (21). But the ' palato-maxillary ' vacuity" (figs. 6 

 and 7, «) between the vomer, maxillary, and palatine, does not exist in Crocodilia ; nor is 

 there a trace in that order of an ' interpalatine vacuity.'^ The ' interpterygoid ' vacuity 

 in Lacertilia * appears to be represented by the much smaller opening which serves as 

 the ' palato-naris,' or hinder orifice of the nasal air-passages in modern Crocodilian 

 genera.* 



\\\ his description of the Caen Gavial {TeJeosaurus cadomensis, Geof.) Cuvier indicates 

 a large vacuity, more advanced in position than the hinder nostril of modern Crocodiles, 

 and more resembling the interpterygoid vacuity' of Lizards (PI. 60, fig. 7, «). This 

 he regarded in the Caen Gavial as the ' palato-naris.'" 



The smaller and more posterior orifice, resembling the ' palato-naris ' of Crocodiliis 

 and Gavialis, and which De Blainville and Bronn affirmed to be the true hinder 

 nostril in the Teleosaurs, Cuvier calls "le trou des arteres," and marks with the letter t in 

 pi. vii, tom. cit. 



The real nature of this foramen in the Teleosaurs is pointed out in my paper " On the 

 Eustachian Canals in Crocodiles,"'' and the accuracy of Cuvier's determination of the 

 ' palato-nares ' in the Teleosaur, is now accepted.^ 



Li some Teleosaurians {Tel. temporalis, Bl., Felagosaurus typus, Bronn) the 'palato- 

 naris,' instead of being broader than long, as in Tel. cadomensis, is narrower and is 

 produced forward into a point, on the same transverse parallel as the pterygo-maxillary 

 vacuities, which are thus reduced in size and, as it were, pushed aside. 



In Hylaochampsa (PI. 60, fig. 25) the vacuity (y) on each side of the bony palate is 

 formed or bounded behind by the pterygoid (2-1) and ectopterygoid (25) and in front by the 

 palatine (20), and probably by a small part of the maxillary (21), though here a portion of 

 the antero-external part of the boundary is broken away. But sufficient remains to show 

 that the vacuity is natural and is homologous with the " grand trou palatine " in 



1 See my 'Anatomy of Vertebrates,' vol. i, p. 157, fig. 98, c, y; "grand trou palatin " of Cuvier, 

 ' Ossemeiis Fossiles,' 4to, torn, v, pt. ii, p. 133, pi. vii, fig. 4 r; also " trou ovale assez grand," p. 259, 

 pi. xvi, fig. 3, Varanus niloticus. 



2 'Anat. of Vertebrates,' tom. cit., fig. 98, D, n. 



3 lb., ib., fig. 98, D, m. 



* lb., ib., fig. 98, D, «. 

 5 lb., ib., fig. 98, c, n. 



^ " La fosse nasale posterieure ;" described as " tres-grande," and marked with the letter s in fig. 4, 

 plate vii, ' Ossemens Fossiles,' tom. cit. 



1 ' Philosophical Transactions,' 1850, p. 521, pis. xl — xlii. 



* E. d'Alton and H. Burmeister, ' Ueber der Fossile Gavial von Boll in Wurtemburg,' &c., 8vo, plates 

 in fol., Halle, 1854, in which the small hinder foramen is called "die vereiuigten Mundungen der Eusta- 

 chischen Roiiren und gewisser Sinusse im Inuern der Ossis occipitis." 



