222 PALAEONTOLOGY 



There is no trace of transverse processes, rib-surfaces, or hasm- 

 apophyses ; this, and the absence of the continuous neural 

 canal, indicate these singular vertebras to belong to the tail. 

 From the long caudo-vertebral style of anourous Batrachia the 

 vertebrae of Tanystrophwus differ in having distinct articular 

 surfaces at both ends. The difference of shape and size in 

 the few that have been found also indicates that there were 

 more than two such vertebras in the tail of the extraordinary 

 animal to which they have belonged. Caudal vertebras of the 

 normal proportions and structure, from muschelkalk of the 

 same localities with Tanystrophceus have been referred to 

 Kothosaurus. It is possible, however, that one or other of the 

 remarkable genera — Simosaurus, Placodus, e.g. — may have 

 possessed the peculiar structure in the tail, or some part of it, 

 which the tanystrophasan vertebras indicate. The first four 

 vertebras of the neck or trunk of the Fistularia tabaecaria are 

 those which most resemble in their proportions the vertebras 

 above described ; but none of the fistularian vertebra? have 

 the articular concavity and the zygapophyses at both ends ; 

 the first presents them at the fore end, and the last at the 

 hind end, and the modifications of both these finished articular 

 ends pretty closely correspond with those of Tanystrophams ; 

 but the second and third vertebra? of Fistularia are united 

 with the first and fourth by sutural surfaces with deeply-inter- 

 locking pointed processes. 



Genus Sphenosaurus. 



Sp. Sphenosaurus Sternbergii, Yon. M. — The fossil vertebra? 

 on which this genus is founded are imbedded in a sandstone, 

 most like the tranter, from Bohemia or the south of Germany. 

 Of the twenty-three vertebras so preserved in nearly their 

 natural position, and with their under surface 1 exposed, five 

 belong to the tail, the rest to the trunk. Of these, two are 

 sacral, two lumbar, the rest are dorsal or thoracic, with long 

 and slender ribs connected with them. The neural arch 



