154 R. OWEN ON THE PURBECK 
palate may have been in amphiccelian Crocodiles we may never 
know ; but the large relative size, the forward position, and the 
horizontal plane of the bony openings oppose the application 
thereto of any such special and complex valvular structures as 
anatomy has revealed in existing Crocodiles. 
If the submergence of the Crocodile with its “large mammalian” 
prey should continue so long as to render it needful for the reptile 
to “take a fresh breath,” it can protrude its prominent snout from 
the surface and inhale a current of air which will traverse the long 
‘meatus ” and enter the glottis by the chamber common to nose and 
windpipe, which is shut out from the mouth by the modifications of 
a “ velum palati” and “ epiglottis ” above explained. The same effect 
results from the ‘‘ uninterrupted tube ” in the proccelian Crocodiles as 
in that of the Cetacea. A teleologist must admit that ‘the con- 
trivance is admirable ;” it is equally effectual in both cases, and a 
Paley might expatiate upon the diversity of means by which the end 
is attained. 
But we have no ground for inferring such means from the struc- 
ture of the bony palate in the fossilized skulls of the amphicoslians ; 
nor does our present knowledge of mammalian life in the Mesozoic 
periods encourage any belief that it was needed. 
EXPLANATION OF PLATE IX. 
Fig. 1. Upper view of skull of Theriosuchus pusillus. 
Fig. 2. Under view of the same skull. 
Fig. 8. Side view of the same skull. 
Fig. 4. Left maxillary, inner side view, young individual, of Theriosuchus. 
Fig. 5. Right maxillary, outer side view, of full-grown individual. 
Fig. 6. Crowns of large canine and three following teeth, magnified. 
Fig. 7. Dentary bone and fragments of mandible, imner side yiew. 
Fig. 8. Portions of humerus, ulna, and radius. 
Fig. 9. Femur. 
Fig. 10. Outer surface of medio-dorsal scutes. 
Fig. 11. Inner surface of ditto. 
Fig. 12. Two dorsal vertebree, under view. 
All the figures, save 6, are of the natural size. 
complete a safeguard of the larynx in an animal breathing air, but destroying 
its living prey by submersion in water.” 
Geoffroy St.-Hilaire, ‘ Description des Reptiles de ’ Egypte,’ p. 236. 
Hunter had left a preparation demonstrating the same structure, which is 
described in the ‘Oatalogue of the Physiological Series in the Museum of the 
Royal College of Surgeons, 4to, 1832, vol. iii. p. 72, Prep. No. 1466. 
See also Ouvier, ‘ Legons d’'Anat. Comparée,’ 8yo, tome iv. (1805), p. 284. 
“‘Tes ouvertures internes des narines sont trés en arriére dans cet animal, 
contre l’ordinaire des autres reptiles,” which other reptiles include the Crocodiles 
not procelian or Neozoic. 
es eee 
