﻿RFIIZOnONTTD.T;. 



349 



Archichthys, A. Hancock & T. Atthey, Aim. Mag. Nat. Hist. 



[4] vol. v. 1870, p. 268. 

 Labyrinthodontosaurus, T. P. Barkas, Coal-Meas. Palaeont. 1873, 



p. 75. 



An imperfectly known genus, comprising species of medium or 

 large size. Teeth subulate, without longitudinal keel, more or less 

 bent inwards, and often sigmoidally curved ; outer face nearly or quite 

 smooth, inner face with vertical striations. Vertebral centra in the 

 form of thin discs, pierced by a large mesial foramen for the passage 

 of the remnant of the notochord. Scales very thin and deeply imbri- 

 cating ; inner surface with a median, antero-posteriorly elongated 

 protuberance, and a hinder sector marked by small pits ; exposed 

 surface relatively small, ornamented with few, large, longitudinal 

 furrows, somewhat radiating and occasionally branching. 



The clavicle and infraclavicle of this genus are identical in form 

 with those of Bhizodus described above (pp. 345, PL XII. figs. 3-6). 



Strepsodus sauroides (liinney). 

 [Plate XVI. figs. 1, 2.] 



1841. Holoptychius sauroides, E. W. Binney, Trans. Manchester Geol. 



Soc. vol. i. p. 165, pi. v. fig. 7.] 

 1844. Holoptychius sauroides, L. Agassiz, Poiss. Foss . vol. ii. pt. ii. 



p. 180 (name only). 

 1844. Holoptychius yarneri, L. Agassiz, ibid. p. 180 (name only). 

 1864. Holoptychius sauroides, Kirkby & Atthey, Trans. Tyneside Nat. 



Field Club, vol. vi. p. 234, pi. vi. figs. 5, 6. 

 1866. Strepsodus, J. Young (ex Huxley, MS.), Quart. Journ. Geol. Soc. 



vol. xxii. p. 602, woodc. fig. 3. 

 1866. Dendroptychius,J. Young (ex Huxley, MS.), ibid. p. 601, woodc. 



fig. 7. [Scale ; Museum of Practical Geology.] 

 1869. Strepsodus, T. P. Barkas, Scientific Opinion, vol. i. p. 556. 



1872. Strepsodus sauroides, G. Lyon, Trans. Edinb. Geol. Soc. vol. ii. 

 p. 125. 



1873. Labyrinthodontosaurus simmi, T. P. Barkas, Coal-Meas. Palaeont. 

 pp. 75, 94, figs. 194, 223, 224. [Fragment of mandible ; T. P. 

 Barkas Collection, Newcastle-upon-Tyne.] 



1873. Strepsodus, T. P. Barkas, ibid. p. 32, figs. 113-119. 



1875. Strepsodus sauroides, J. Ward, [Proc] N. Staffs. Nat. Field Club, 



p. 232. 

 1875. Rhizodus (Holoptychius) yarneri, J. Ward, ibid. p. 233, fig. 4. 



[Scale ; J. Ward Collection, Longton.] 



1875. Dendroptychius, J. Ward, ibid. p. 233. 



1876. Strepsodus, W. J. Barkas, Monthly Rev. Dental Surgery, vol. iv. 

 pp. 481, 529, figs, lxxxvi.-lxxxviii. 



