136 ELOPIFORM FISHES 



with the lateral margin, of their respective infrapharyngobranchials. The anterior 

 ends of the second and third infrapharyngobranchials have two heads, one directed 

 antero-medially, the other directed antero-laterally and joined by cartilage to the 

 epibranchial of the preceding arch. 



The fourth epibranchial is unusual in showing three dorsal processes. Basically 

 this element has two heads, like the anterior epibranchials, but the posterior projec- 

 tion has become subdivided. The significance of this subdivision is not clear. The 

 fourth infrapharyngobranchial has the same relationship to its epibranchial support 

 as those anteriorly, but is represented by a simple semi-ovoid cartilage having no 

 connection with the antecedent epibranchial. 



Upper pharyngeal tooth plates are associated with the second, third and fourth 

 infrapharyngobranchials. The third infrapharyngobranchial tooth plate is triangular 

 while the fourth is divided into two sections, one associated more closely with the 

 epibranchial, the other more closely associated with the infrapharyngobranchial. 



In addition to the basibranchial and upper pharyngeal dentition there are tooth 

 plates associated with the oral surface of all cerato- and epibranchials and the first 

 two hypobranchials. The tooth plates associated with these elements appear to be 

 aligned in three rows, anterior, middle and posterior. The plates of the anterior 

 row of the first arch are modified into gill-rakers which consist of a bulbous, toothed 

 head supported on a slender stalk. The tooth plates of the posterior row on the 

 fifth ceratobranchial are enlarged to form the lower pharyngeal tooth plate. Each 

 tooth plate bears several pointed teeth. 



Pectoral girdle and fin. The main body of the post-temporal is represented by a 

 flat plate of bone, pierced laterally by the lateral line. Two processes arise from the 

 ventral surface of the main body : projecting anteriorly there is a spinous epiotic 

 or dorsal limb, while ventrally there is a thicker intercalar or ventral limb. 



The supracleithrum is elongate, rounded at both ends, and shows a slight indenta- 

 tion in the posterior margin. The lateral line passes obliquely through the upper 

 half of the bone. The cleithrum is large. Above the fin insertion the bone is ex- 

 panded to provide support for the large axillary scale. Anteriorly the cleithrum 

 is tapered and is joined to its partner by a strip of tough connective tissue. Through- 

 out its length the anterior margin of the cleithrum is turned medially providing a 

 broad area of insertion for the sternohyoideus musculature. 



The coracoid is aliform and, unlike that of elopoids, does not extend to the tip 

 of the cleithrum. Between the anterior and posterior connections of the cleithrum 

 and coracoid there is a slit-like fenestra. The scapula is circular save for a deep 

 notch anteriorly which represents an incomplete scapular foramen. The meso- 

 coracoid is stout, particularly ventrally where it contacts the scapula and coracoid 

 through a large area of cartilage. As in most albuloids the anterior margin of the 

 mesocoracoid arch has contact with the cleithrum over much of its length. 



All but the outermost pectoral fin-ray are supported by the four proximal radials, 

 which although of basic teleostean form, articulate with cartilage and are not, as is 

 usual, directly related to the scapula and coracoid. The outermost fin-ray arti- 

 culates both directly and indirectly with the scapula. Between the halves of the 

 outermost ray there is a small ovoid element consisting of an ossified core surrounded 



