156 



ELOPIFORM FISHES 



50C 



Ot.S.C 



Ptf 



sef 



boc 



5 mm 



Fig. 76. Albula vulpes (Linnaeus). Neurocranium in posterior view. 

 Composite of several B.M.N.H. specimens. 



In posterior view (Text-fig. 76) the neurocranium shows large sub-epiotic fossae, 

 small post-temporal fossae and large otic bullae. The supraoccipital is relatively 

 larger than in Pterothrissus, due to its more extensive ossification. Two further 

 features of interest in the posterior neurocranial wall of A. vulpes are the small 

 ' isolated ' portion of the pterotic and the foramen between the epiotic and supra- 

 occipital. The ' isolated ' portion of the pterotic represents the wall of the caecal 

 end of the subtemporal fossa. Such a condition of the pterotic appears to be unique 

 among lower teleosts, but in these the subtemporal fossa is rarely as deep, and even 

 more rarely is it associated with a deep sub-epiotic fossa. The foramen between the 

 supraoccipital and epiotic is occupied by epaxial musculature passing through to the 

 post-temporal fossa. 



The intercalar is small, as usual in albuloids, with little extension on the lateral 

 face of the neurocranium. Posteriorly the surface of the intercalar bears ridges 

 for the insertion of the tendon from the post-temporal. 



The lateral neurocranial wall has in part been described by Ridewood (1904). 

 Significant points are the depth of the roofed dilatator fossa ; the posteriorly placed 

 opening of the jugular canal, close to the suture between the prootic and exoccipital ; 



