SARDINIOIDES. 35 



part of the cheek between the anterior half of the orbit and the maxilla. It shows 

 traces of the usual slime-canal with radiating branches. Behind the circumorbital 

 ring there are remains of large thin scales on the cheek. 



The mandibular suspensorium is slightly inclined forwards, so that the quadrate 

 articulation is beneath the hinder border of the orbit. The premaxilla (fig. 1 a, 

 pmx.) is remarkably slender, completely excluding the maxilla from the gape ; and 

 the anterior half of its oral border is quite wide and tumid for the support of a 

 cluster of minute teeth. The maxilla {vix.) is a stouter, laterally compressed bone, 

 gradually expanding a little behind, and ornamented on its outer face with fine 

 rugae or partially subdivided ridges, of which the majority are directed obliquely to 

 its long axis. The supramaxillas (smx. 1, 2) extend along the hinder half of the 

 maxilla, and resemble the two corresponding elements of the existing Aulojjus (PI. 

 X, fig. 2). The mandible (md.) is a thin lamina much curved inwards below, and 

 somewhat contracting and thickening to a truncated symphysis in front. Its oral 

 border bears clustered minute teeth, and its oviter face, where well preserved, is 

 seen to be finely rugose. 



The preoperculum {pop.) has a nearly vertical ascending limb, tapering to the 

 upper end of the hyomandibular. Its angle is gently rounded and not much 

 expanded,, while its lower limb is comparatively short but wide. Its outer face 

 seems to have been nearly smooth, and its hinder border is not serrated. The 

 operculum {op.) and suboperculum {sop.) are rounded behind and below, and the 

 latter element is relatively large, extending far upwards behind the operculum 

 itself. Both bones are ornamented with a delicate rugosity, which tends towards 

 a radiating arrangement on the operculum. Traces of long and slender branchio- 

 stegal rays are seen {hr.). 



The centra of the hinder abdominal vertebrjB (fig. 1 h) are not longer than deep. 

 They are much constricted, and strengthened by one median latei'al ridge. The 

 ribs are slender and articulate directly with the centra, which do not bear trans- 

 verse processes. 



The pectoral fins {pd.) comprise not less than 10 or 11 rays, of which only the 

 bases are preserved in the fossil. The pelvic fins {p)h\) are shown to have been 

 far forwards, with rays much stouter than those of the pectorals. The dorsal fin 

 {d.) also arises far forwards, and consists of very stout rays. It is crushed down- 

 wards to the left in the fossil, and its winged, dagger-shaped supports (/.) are 

 exposed to the right. Only 10 dorsal fin-rays are clearly seen, though there w^ere 

 possibly more in the original fish; and their articulated distal ends are almost 

 entirely wanting. 



The scales are large and thin, and Avhen their outer face is well preserved they 

 are observed to be delicately pectinated at the hinder margin. 



Horizon and Locality. — Unknown, but probably from one of the lower zones in 

 the Burliam district, Kent. 



