138 Frederick Chcqmian : 



author himself was dubious about referring it to Lamna. Dr. A. S.. 

 Woodward, in his " Catalogue of Fossil Fishes, "^ remarks upon it 

 as follows : — 



" The so-called Lninna lanceolata, J. W. Davis (Trans. Roy. 

 Dublin Soc, 2 vol. IV., 1888, p. 20, pi. III., fig. 12), from New 

 Zealand, is founded upon a tooth evidently not Selachian." 



Whilst studying the structure of the rostral teeth in the living 

 Prist is and allied genera, I was struck with the resemblance of 

 Davis's fossil with the teeth of the Hobson"s Bay Saw-shark, Pris- 

 tiophorus. Their generic identity ^w^as confirmed from the fol- 

 lowing features common to both. The flattened crown of the tooth is 

 equally, slightly convex on both surfaces. The base of the tooth is 

 not furnished with a definite semi -calcified root as in Lamna, but 

 appears to Ix; torn from its base, suggesting a cartilaginous attach- 

 ment. The tooth curves gently backwards, and at its junction 

 with the basal cartilage the osteodentine is clearly marked off from, 

 the base. This line of attachment bends down to the anterior margin, 

 in both living and fossil species. The hoUoAv root of the fossil teeth 

 further indicates a hollow or membranous base seen on the rostral 

 margin of the living Prisfiophorus.- 



The teeth of Pristiophorus lanceolatus are closely comparable to 

 those of P. nudipiunis, Giinther,'^ (PI. IX., fig. 6). a saw-fish found 

 in Hobson's Bay, Port Phillip, with these differences : — 



The fossil specimens are larger, stouter and more strongly curved. 

 The size of the Victorian specimen indicates a fish of about four and 

 a-half feet long, whilst that from New Zealand would have l^een 

 about six feet or more. 



The genus Pristiophorus is rare in the fossil condition, being only 

 represented by some detached vertebrae from the Molasse of Balt- 

 ringen, Wiirtemberg,* and by an undescribed form from the Uppei- 

 Cretaceous of Mount Lebanon (Smith Woodward). 



J. W. Davis's specimen came from the Oamaru series at Castle Hill. 

 Station, Canterbury, N.Z. 



Occurrence. — Tertiary (Kalimnan). Beaumaris. Pres. by Mr. 

 F. A. Cudmore. 



1 Parti., 1889, p. 410. 



•2 In workiiijc out the relationships of this and other fossil specimens I have been kindly assisted 

 by .Mr. J. A. Kershaw, F. U.S., Curator of the Museum, who has given facilities for examining recent 

 specimens. 



3 GUiither. Cat. Foss. Fishes, Brit. Mus., vol. viii., 1864, p. 432. .McCoy, Prod. Zool. Vict.^. 

 vol. i., 1885, pi. Ivi., fiff. 2. 



4 llasse, C. " Das natiirl. Syst. Elasm., Besond. Theil,"' p. 103, pi. xiii , fiifs. 0, 7. 



