SEA-SERFENTS. 



143 



American Cretaceous sea, and reached a length of seventy-five 

 feet. It had a long projecting muzzle, somewhat like the snout 

 of a sturgeon. Platecarpus and Tylosaurus had peculiarly sharp- 

 pointed heads (see Fig. 40). 



Fig. 40. — Snout of Tylosaurus. (After Marsh.) 



A few words may be added here with regard to Professor 

 Cope's important discovery of Leiodon — a genus already alluded 

 to as having been founded by Sir Richard Owen. The type 

 specimen of Leiodon dyseplor/ which first indicated the characters 

 of this wonderful species, was obtained from the yellow beds of 

 the Niobrara epoch of the Jornada del Muerto, near Fort INIcRae, 

 New Mexico. The greater part of the remains have been 

 described by Professor Leidy. But a second specimen, more 

 complete in all respects, was discovered by Professor Cope's 

 exploring party during an expedition from Fort Wallace, Kansas, 

 in 187 1. This specimen he has fully described and figured in 

 the report already referred to (p. 140). It is a very instructive 

 specimen, including fifty of the vertebrae from all parts of the 

 vertebral column, a large part of the cranium, with teeth, as well 

 as important limb-bones. These precious relics were excavated 

 from a chalk " bluff," or high bank. Fragments of the jaws were 

 seen lying on the slope, and other portions entered the shale. On 

 being followed, a part of the skull was taken from beneath the 

 roots of a bush, and the vertebrae and limb-bones were found 

 farther in. The series of vertebrae, after extending some way 

 along the face of the bluff, finally turned into the hill, and were 



' We retain the old spelling with the e as being nearer to the Greek, 

 although Professor Cope writes it " Liodon." 



