656 ME. A. SMITH WOODWAEl) ON THE SO-CALLED [NoV. 20, 



Saliiionoids, have been assiduously' collected since tbe days of 

 Mantell, and are well represented in many museums ; but nothing 

 of importance with reference to their osteology has been published 

 within the last half-century. It is impossible to make further 

 progress in comprehending the fish-fauna of the Cretaceous period 

 until a detailed study of all the known skeletons has been accom- 

 plished ; and it is the object of the present communication to 

 begin such a review of the materials at present available for 

 discussion. 



A beginning is made with the so-called Salmonoids of the English 

 Chalk, because these have been the least elucidated by recent 

 discoveries in corresponding strata elsewhere. The great Sauroid 

 fishes like Portheus and the long-snouted Protosphyrcvna have been 

 discovered in perfection in the Chalk of North America, while 

 Encliodus and Dercetis have been found beautifully preserved in 

 Westphalia and the Lebanon; but tolerably complete specimens 

 related to the supposed Salmonoid Osmeroides are known only from 

 the Chalk of Bohemia, and as these exhibit merely natural casts 

 of the actual fossil they are comparatively unsatisfactory for study. 



The generic name Osmeroides was originally given by Agassiz to 

 some fishes from the Cretaceous of Westphalia, regarded by Pictet 

 and the present writer as undoubted Scopeloids. Many examples 

 of these species exhibit very distinctly the characteristic exclusion 

 of the maxilla from the margin of the upper jaAv ; and they have 

 few, well-spaced branchiostegal rays, without any gular plate. 

 When the same name was afterwards applied to fossils discovered 

 by Dr. Mantell in the English Chalk, it was expressly stated by 

 Agassiz that the determination of generic identity was uncertain 

 and provisional ; and the following description will demonstrate 

 that the Westphahan and Enghsh fishes in question belong even to 

 distinct families. Although Agassiz himself hesitated to distinguish 

 between Salmonoids aud Clupeoids when dealing with fossils, pre- 

 ferring to combine them in one family " Halecidte," subsequent 

 authors appear to have unanimously assigned the English Osmeroides 

 lewesiensis to the Salmonidae. It is thus of much interest to turn 

 to a detailed examination of the known specimens. 



1. Osmeroides lewesiensis. (Plate XLII.) 



Osmeroides leiuesiensis, L. Agassiz, Poiss. Foss. vol. v. pt. i. 

 p. 14, pt. ii. p. 105, pi. Ix. b. figs. 1, 2, 5-7 (nee figs. 3, 4), pi. Ix. c. 

 (1834-44) ; A. S. Woodward, Proc. Geol. Assoc, vol. x. p. 322 

 (1888). 



Salmo lewesiensis, G. A. Mantell, Eoss. South Downs, p. 235, 

 pi. xxxiii. fig. 12, pi. xl. fig. 1 (1822). 



Osmeroides mantelU, L. Agassiz, Neues Jahrb. f. Mineral. 1839, 

 p. 121 (name only) ; G. A. Mantell, Wonders of Geology, ed. 3, 

 vol. i. p. 427 (1839). 



Though many of the smaller features in the skeleton of this 

 fish still remain to be discovered, nearly all its principal characters 

 can now be ascertained. The beautiful series of specimens in the 



