﻿SQUALOEAIID.E. 



41 



plates already described in the upper jaw. A recent examination 

 of this unique fossil in Edinburgh has convinced the writer of the 

 correctness of Dr. Traquair's determination of the affinities of the 

 fish. 



Squaloraja polyspondyla, Agassiz. 



[Plate III. fig. 2.] 



1833. Squaloraia dolichognathos, H. Riley, Proc. Geol. Soc. vol. i. p. 484 



(specific name inappropriate). 

 1837. Squaloraia dolichognathus, H. Riley, Trans. Geol. Soc. [2] vol. v. 



p. 83, pi. iv. 

 1836. Spinacorhinus polyspondylus, L. Agassiz, Poiss. Foss. vol. iii. 



pis. xlii., xliii., and Feuill. p. 94. 

 1843. Squaloraja polyspondyla, L. Agassiz, ibid. vol. iii. p. 381. 

 1872. Squaloraja polyspondyla, W. Davies, Geol. Mag. vol. ix. p. 145, 



pi. iv. 



1885. Squaloraja polyspondyla, C. Hasse, Palgeontogr. vol. xxxi. p. 4, 

 pi. i. figs. 2, 3. 



1886. Squaloraja polyspondyla, A. S.Woodward, Proc. Zool. Soc. p. 527, 

 pi. Iv. figs. 1-5, 7, 8, and ibid. 1887, p. 481. 



Type. Imperfect skeleton ; Bristol Museum. 



The type species, usually not exceeding 0*45 in length. Head 

 occupying more than one third of the total length ; distance between 

 pectoral and pelvic arches two thirds as long as the head ; caudal 

 region attenuated. Rostral spine of male slender, depressed oval in 

 section, terminating bluntly and not excessively attenuated, occu- 

 pying more than three quarters the length of the rostral cartilage ; 

 claspers of male robust, with a small distal cluster of slender 

 recurved hooklets. Dermal tubercles sparse, a regular series of 

 prominent hooklets on each lateral margin of the tail. Mandibular 

 and palatine teeth about six and a half times as long as their maxi- 

 mum breadth, the symphysial portion somewhat raised and tumid. 



Form. Sf Loc. Lower Lias : Dorsetshire. 



The following specimens were all obtained from the Lower Lias 

 of Lyme Regis. 



43307. Head, vertebral column, and fragments of pelvic fins, de- 

 scribed and figured by W. Davies, loc. cit. 



Purchased, 1872. 



P. 2276. The nearly complete skeleton of a male, wanting only a 

 small portion of the caudal region ; described and figured 

 by the present writer, loc. cit. Purchased, 1882. 



