220 



REPTILIA 



CLASS III 



from the acetabuluni, and borne on a prominent anterior process of the 

 ischium. The pubis is more or less spatula-shaped ; the ischium resembles the 

 scapula; and the ilium is a strong bone with curved upper margin, and 

 extended antero-posteriorly. Its enlarged anterior portion is attached to the 

 sacral ribs. The femur is longer and more slender than the humerus, and 

 without an inner trochanter ; tibia and fibula are of about equal proportions. 

 There are two rather large proximal tarsals, a calcaneum (fibulare) and 

 astragalo-scaphoid, the latter representing the coössified tibiale, centrale, and 

 intermedium. Two bones are likewise present in the distal row, of which the 

 cuboid is the larger, and supports the third, fourth, and the rudimentary fifth 

 metatarsal. The three inner digits of both pes and manus are provided 

 with claws. 



A longirostrate section of JEusuchia is constituted by the gavials, which 

 correspond to the mesosuchian Teleosaurs, and may possibly have been 

 descended from them. Modern crocodiles and alligators form the brevirostrate 



section, but between these types are some 

 annectant fossil forms, such as Tomistoma, etc. 



Family 1. 

 Tomistomidae. {Rhynchosuchidae, Hiixley.) 



Snout much produced, passing gradually info the 

 facial region. Nasals long and narrow, their anterior 

 ends intercalated between slender processes of the pre- 

 maxillae, but not reaching the external nostril. Pre- 

 frontals small, lachrymals large. Orbits irregularly 

 oval, nearly as large as, or larger than the supra- 

 temporal vacuities, and confluent with the lateral 

 temporal fossae. Ventral armour absent. Upper 

 Cretaceous to Kecent. 



Thoracosaurus, Leidy (Sphenosaurus, Ag.). 

 Premaxillae spatulate in form, lachrymals uii- 

 usually large. Supratemporal vacuity trans- 

 versely oblong, slightly larger than the orbits ; 

 small antorbital vacuity present. About twenty- 

 four curved teeth on either side in each jaw. 

 Upper Cretaceous ; New Jersey, Holland, and 

 France. 



Holops, Cope. Like the preceding, but 

 without antorbital vacuity, and orbits of equal 

 size with supratemporal vacuities. Upper Cre- 

 taceous ; New Jersey. 



Tomistoma, Müller (Bhynchosuchus, Huxley , 

 Gavialosuchus, Toula and Kail), (Fig. 324). 

 Orbits almost twice the size of supratemporal 

 vacuities. Parietals small, lachrymals moderately developed. About twenty 

 teeth on either side in each jaw. Miocene ; Hungary, Malta, and Sardinia, 

 and Recent in Borneo. 



Q^J 0» 



Fig. 324. 



Tomistoma eggenhurgensis, Toula and 

 Kail. Miocene ; Eggenburg, near Hom, 

 Austria. Dorsal aspect of skull, i/io» 

 Lettering as in Fig. 325. 



