112 



ELOPIFORM FISHES 



de 



sosc 



ot s.c 



soc 



10 mm 



Fig. 54. Osmeroides levis Woodward. Neurocranium in dorsal view. Based on 

 B.M.N. H. P.5681, P.1854 and 49903. 



The cranial roof is shorter in proportion to its width than in the type-species and the 

 parietal bones are shorter than long. Perhaps the most easily recognizable differ- 

 ence noted by Woodward concerns the ornamentation of the skull roofing bones, 

 those of 0. levis being smooth except for a small patch of rugose ornamentation on 

 the frontal bones above the orbit, whereas the roofing bones of the type-species are 

 uniformly ornamented from the mid-orbital region posteriorly. 



In addition to the above differences several others may be mentioned. The 

 dermethmoid of 0. levis is considerably shorter than that of the type-species and this 

 is related to the preorbital length which is less in 0. levis. 



The parasphenoid of 0. levis is relatively narrow and terminates beneath the 

 middle of the otic region of the neurocranium, contrasting with the very broad, long 

 parasphenoid of 0. lewesiensis. In both species the parasphenoid bears a patch of 

 very small, rounded teeth. The size of the parasphenoid has resulted in other 

 differences between the two species. The parasphenoid rests against the lateral 

 ethmoid in both, but in 0. lewesiensis there is a sutural connection between these 



