FKOM THE WEALDEN AND PTJEBECiC FORMATIONS. 381 



of the former (No. 41,098), viewed from above, is less elongated than 

 in Gavialis, longer than in Alligatoridse, and not very unlike that of 

 a typical crocodile, as the C. rhombifer figured by Cuvier. 



In the arrest of the nasal bones short of the anterior nares, the 

 skulls of this group differ from those of alligators and of many cro- 

 codiles proper, and they resemble Gavialis, differing, however, from 

 this in the further forward extension of the nasals. In this respect 

 they more resemble the Bornean Bhynchosuchus Schlegelii and Cro- 

 codilus catajphr actus; and to these they present another resemblance 

 in the form of the palato-nares, which in Bhynchosuchus are more 

 axially lengthened and less concealed by the centrally-joined plates 

 of the pterygoid bones than in all other extant crocodiles. 



I am inclined to look on Mr. Willett's and the Brook skull as 

 belonging to one species, any differences being dependent on their 

 widely different ages; and in order to avoid the multiplication of 

 genera, I would provisionally place them both in Goniopholis, be- 

 lieving they will rest there. The Swanage skull (No. 41,098) should 

 also find its place with them ; but I suspect it will prove to be 

 specifically distinct. 



Holding, as they all three do, an intermediate position as to their 

 palatal nares and other anatomical features, and occurring in time 

 intermediately between the Mesosuchia of the Lias and Oolite and 

 the Eusuchia (as has been shown by Prof. Huxley for the Brook 

 skull), I would suggest that they may be properly placed in an 

 intermediate subgroup of the Crocodilia, which, following Prof. 

 Huxley's classification, might be designated Metamesosuchia. 



Thus intercalated between the Liassic and Oolitic crocodilians 

 represented by Pelagosaurus typus, Metriorhynchus Blainvillii, Ste- 

 neosaurus Larteti on the one side, and the Eusuchia on the other, 

 the palato-nares are seen to move backwards from the advanced 

 position they occupy in Pelagosaurus (in which they are mainly 

 placed between the divergent inner borders of the palatine bones), 

 through this group (in which they are formed jointly by the pala- 

 tines and pterygoids, the latter becoming connate between them 

 and the median Eustachian opening), to the very posterior position 

 they occupy in the Crocodilians of our own times. 



The crushed condition of the Purbeck and Brook skulls makes it 

 impossible to learn whether a distinct supraorbital bone is present 

 in them, as it is in Mr. Willett's Goniopholis. From a comparison 

 of it with the palpebral ossifications in Caiman palpebrosus, I doubt 

 its homology with these; but I speak with reservation, as only 

 young individuals of this Caiman have been at my disposal. 



EXPLANATION OF PLATE XV. 



Fig. 1. Goniopholis crassidens? (in Mr. Willett's collection), upper surface, 



one fourth natural size. 

 Fig. 2. Under surface of same. 



Fig. 2 a. Tooth of Goniopholis crassidens, natural size. 



Fig. 3. Upper surface of skull No. 41,098 Brit. Mus., one fourth natural size. 

 Fig. 4. Under surface of same, showing the palato-nares. 



In figs. 2 and 4: pi, palate-bone; pt, pterygoid bone; pn, palato-nares; 

 Eu, median Eustachian orifice. 



