﻿502 ACTISTOPTERYGUI. 



1833. Acrolepi's sedgwicki, L. Agassiz, Neues Jabrb. p. 476, and Poiss. 



Foss. vol. ii. pt. i. p. 11. 

 1833. Ggrolepis asper, L. Agassiz, ibid. p. 473, and ibid. p. 6. 

 1835. Acrolepis sedgwickii, F. A. Quenstedt, Wieginann's Arcbiv. 



Naturg. vol. ii. p. 92. 



1839. Paheoniscus dunkeri, G. A. Kurtze, Comment. Petrefact. Mans- 

 feld. pp. 16, 37, pi. i. 



1840. Palceoniscus dunkeri, E. F. Germar, Verstein. Mansfeld. Kupfer- 

 scbief. p. 19, figs. 1-5. 



1841. Acrolepis asper, L. Agassiz, Neues Jabrb. p. 614. [British 

 Museum.] 



1842. Acrolepis dunkeri, G. von Miinster, Beitr. Petrefakt. pt. v. p. 40. 

 (?) 1842. Acrolepis angustus, G. von Miinster, ibid. p. 40. [Palaeonto- 



logical Museum, Munich.] 

 (?) 1842. Acrolepis giganteus, G. von Miinster. ibid. p. 41. [Ditto.] 

 1844. Acrolepis sedgwickii, L. Agassiz, Poiss. Foss. vol. ii. pt. ii. p. 80, 



pi. Hi. (plate published 1839). 

 1844. Acrolepis asper, L. Agassiz, ibid. p. 81. 

 1848. Acrolepis sedgwickii, C. G. Giebel, Fauna der Vorwelt, Fische, 



p. 241. 

 1848. Acrolepis asper, 0. G. Giebel, ibid. p. 241. 

 1850. Acrolepis sedgivickii, Sir P. Egerton, in King's Permian Foss. 



(Pal. Soc), p. 234, pi. xxv. 

 1861. Acrolepis sedgwicki, H. B. Geinitz, Dyas, p. 13. 

 1861. Acrolepis asper, angustus, and giganteus, H. B. Geinitz, ibid. 



pp. 13, 14. 



Type. Caudal portion of fish ; olim Witham Collection. 



The type species, attaining a length of about 0*7. Maximum 

 depth of trunk contained about six times in the total length. Head 

 and opercular apparatus occupying one-fifth of the total length ; 

 snout obtusely pointed ; hinder expansion of maxilla three quarters 

 as high as broad, truncated above, its postero-mferior portion pro- 

 duced downwards in a small rounded expansion, bearing smaller 

 teeth than the other part of the dentigerous border ; large teeth 

 short and stout, but acutely pointed; ornamentation of cranial, 

 facial, and opercular bones almost uniform, consisting of coarse 

 tuberculations, with a tendency towards elongation and partial 

 fusion into parallel rugae ; tubercles of rostral region mostly rounded, 

 those bordering the jaws the smallest. Pelvic fins about half as 

 large as the pectorals, situated much nearer to the anal than to the 

 ] atter ; dorsal and anal fins deeper than long, of nearly equal size, 

 (he dorsal precisely opposed to the space between the pelvic fins 

 and the anal, to which its base-line is almost equal in extent. 

 Scale- ornament very coarse, the flank-scales each marked by about 

 six broad, rounded, antero-posterior ridges, of which those on the 



