II.] SURVIVAL OF OLD FORMS. 63 



Fiji) is spread over India, Ceylon, and the south of China ; while 

 the absence of caimans and jacaras from Notogaea aifords, so far 

 as it goes, an additional argument that any land connection which 

 may have existed in Tertiary times between Australia and South 

 America must either have been very transitory, or must have been 

 situated in such latitudes that tropical forms could not have used 

 it as a means of transit. 



Of more importance than all is the tuatera lizard (Sphenodon) of 

 New Zealand the sole existing representative of the order 

 Rhynchocephalia, since this curious creature is closely allied to 

 the extinct Rhynchosanrus and Hyperodapedon of Triassic strata of 

 the northern portion of the Old World. Finally, the Port Jackson 

 shark (Cestracion philippi) belongs to a genus which was living in 

 the seas of Europe during the Jurassic and Cretaceous periods ; 

 and the sole living survivor of the. swarms of species of the 

 Molluscan genus Trigonia inhabiting the same seas occurs in 

 Australian waters. 



