GANOCEPHALA. 193 



three, presented a diameter for each foot-print of about two 

 inches, and shewed the fore and hind feet to be nearly equal 

 in dimensions. It exhibits a length of stride of about nine 

 inches and a breadth between the right and left footsteps of 

 nearly four inches. The impressions of the hind feet are but 

 little in the rear of the fore feet. With these foot-marks were 

 associated shrinkage cracks, such as are caused by the sun's 

 heat upon mud, and rain-drop pittings, with the signs of the 

 trickling of water on a wet beach, — all confirming the con- 

 clusions derived from the foot-prints, that the quadrupeds 

 belong to air-breathers, and not to a class of animals living in 

 and breathing water. 



Class IL — REPTILIA. 

 Order I. — Ganocephala* 



The name of this order has reference to the sculptured 

 and externally polished or " ganoid" bony plates with 

 which the entire head was defended. These plates 

 include the " post-orbital" and " super-temporal" ones, 

 which roof over the temporal fossae. There are no 

 occipital condyles. The teeth have converging inflected 

 folds of cement at their basal half. The notochord is 

 persistent ; the vertebral arches and peripheral elements 

 are ossified ; the pleurapophyses are short and straight. 

 There are pectoral and pelvic limbs, which are natatory 

 and very small ; large median and lateral " throat- 

 plates ;" scales small, narrow, sub-ganoid ; traces of 

 branchial arches. 



The extinct animals which manifest the above combina- 

 tion of characters were first indicated by certain fossils, 

 discovered in the sphserosideritic clay-slate forming the 

 upper member of the Bavarian coal measures ; and also 



* Tavoe, lustre ; xi<pa.\r>, head. 

 



