FOSSIL AND RECENT 153 



The caudal skeleton has six slender hypurals and a half neural spine on the second 

 preural centrum. The neural and haemal spines are not expanded, in contrast to 

 those in albulids. Preceding the upper and lower principal rays there is, as in Istieus 

 and Pterothrissus, a series of very slender basal fulcra. Two B.M.N.H. specimens 

 (P. 13905 and P. 13906), although reasonably well preserved in the caudal region, 

 show no caudal scutes as recorded by Woodward (1942). In contrast to other 

 pterothrissids, there are three uroneurals. 



The vertebral column, with 50-55 vertebrae, is shorter than in other pterothrissids, 

 but other features, although of a primitive nature, agree with this group. The 

 anal fin is very short, consisting of only seven rays, unlike the longer anal fin of 

 Istieus and Pterothrissus. 



The pectoral girdle of Hajulia, with the fin inserted just beneath the level of the 

 vertebral column, is unlike that of the pterothrissids. In this, and the shape of 

 the ventral part of the cleithrum, there is a resemblance to the tselfatioids (sensu 

 Patterson 1967c), but there is nothing else about Hajulia to suggest such an affinity. 



The sum of these briefly noted morphological characters indicates that Woodward's 

 (1942) suggested affinity of Hajulia was correct. However, incomplete knowledge 

 of Hajulia precludes anything but a tentative assignment to the Pterothrissidae, 

 and in consequence a fuller discussion of this genus is omitted. 



Family ALBULIDAE Bleeker, 1859 



Diagnosis. Albuloid fishes in which the snout is elongated, mouth inferior. 

 Ethmoid commissure incomplete, running through premaxillae. Supraorbital 

 sensory canal not extending onto parietal. Occipital condyle formed by basioccipital. 

 Interorbital septum ossified. Lateral ethmoid sutured with broad parasphenoid. 

 Parasphenoid and endopterygoid with a prominent crushing dentition opposed by 

 similar dentition upon the basibranchial tooth plate. Basihyal tooth plate eden- 

 tulous or absent. Vomer, dermopalatine, premaxilla and dentary with small needle- 

 like teeth. Posterior infraorbitals broad, covering cheek. Supraorbital small. 

 Hyomandibular-metapterygoid foramen present. Premaxilla tightly bound to 

 mesethmoid ; maxilla moving independently, a single supramaxilla. Mandible 

 with low coronoid process situated posteriorly ; articular and endosteal articular 

 ossified separately. Branchiostegals more than 12 in number. Gular plate present. 

 Dorsal and anal fins short based. Caudal skeleton with a full-length neural spine 

 associated with the second preural centrum, two uroneurals. Inner caudal rays 

 of each lobe without expanded bases. Caudal scute present above and below 

 peduncle. 



Genus ALBULA Scopoli, 1777 



For synonymy see Hildebrand (1963). 



Diagnosis (emended). Albulid fish in which the mouth is decidedly inferior, 

 the maxilla is edentulous and extends to the anterior margin of the eye. Quadrate/ 

 mandibular articulation beneath anterior half of the orbit. Gular plate very small 



