122 



REPTILES 



of the Isle of Wight. 

 The latter was a re- 

 markable dinosaur, in 

 which, in addition to 

 a double row of broad 

 compressed spines 

 along the neck and 

 back, a huge solid 

 buckler, dotted over 

 with prominent bosses 

 to which other spines 

 were articulated, pro- 

 tected the whole of 

 the hind quarters. 

 The lumbar shield, as 

 in tortoises, is firmly 

 welded to the pelvis. 



The dermal ar- 

 mour is most com- 

 pletely preserved in 

 the genus Stegosaurus, 

 represented by species 

 from the Upper Juras- 

 sic strata of North 

 America, and having 

 a near ally in the 

 Kimeridge Clay of 

 England, which has 

 been described under 

 the name of Omosau- 

 rus. In this ungainly 

 monster, which mea- 

 sured close on thirty 

 feet in length, with an 

 extreme height of ten 

 feet, the dermal ar- 

 mour took the form 

 of two parallel rows 

 of vertical crest-like 

 plates i gradually in- 



