SARDINIOIDES. 



33 



Type Species. — Sardinioides monasteri {Osmeroldes monasterii, Agassiz, Poiss. 



3., vol. V, pt. ii, 1839-44, p. 103, pi. \xd, fig. 3), from the Senoniaii of 

 Westphalia. 



Remarks. — The species of this genus are common in the Upper Cretaceous of 

 Westphalia and Mount Lebanon, and the external aspect of one of the typical 



Fig. 6. Sardinioides crassicaudus, W. von der Marck ; restoration, about one-half nat. size. — 

 Senonian ; Westphalia. The hinder extension of the suboperculum here represented is hypo- 

 thetical, not yet observed. 



forms is represented in the accompanying restoration, Text-fig. 6. The cranium of 

 the genus has hitherto remained almost unknown; but the head of one Westphalian 

 specimen in the British Museum (no. 43010), favourably exposed from above, seems 

 to show a cranial roof identical with that of an Endish Chalk fossil, which other- 



^^^^^^^ 



Fig. 7. ChloropMhalmus chalyheius, Goode ; about nat. size.- 

 After Goode and Bean. 



-Existing in moderately deep sea. 



wise displays several features in common with Sardinioides. The new specimen 

 described below, if correctly identified, is thus of importance as affording the first 

 clear view of the top of the cranium of Sardinioides, demonstrating its close resem- 

 blance to the corresponding part of the existing genus Aulopus (PI. X, figs. 2, 2 a). 

 The whole aspect of the head and opercular apparatus in the new 8. illvstraus is, 



5 



