Clupeoid Fish from the English Chalk. 325 



of an antorbital is preserved (fig. 2, a.o.'), but this is inter- 

 esting as exhibiting downwardlj-radiatiiig branches from the 

 slime- canal which traverses it. There are remains of the two 

 large supramaxillEe [s.mx.) overlapping the maxilla {mx.)^ of 

 which the convex oral border is beset with minute teeth. The 

 rather stout premaxillfe must clearly have met in the middle 

 line, and that of the right side exhibits a considerably 

 extended oral face with the bases of attachment for a cluster 

 of minute teeth. The mandible {md.) is fragraentaiy, but 

 its articulation is shown beneath the hinder border of the 

 orbit. The deep and narrow preoperculum [p-op.) has a 

 straight vertical anterior margin which is somewhat thick- 

 ened. The lower limb of this bone is small, and from its 

 angle there are a few radiating ridges. The operculum {pp.) 

 is delicate and deeper than broad, and a few of the charac- 

 teristic cycloidal scales extend both over this bone and over 

 the cheek. Of the trunk only the lower portion is preserved, 

 but this is complete to the base of the caudal fin (c). There 

 are -remains of the comparatively small pectoral fins [pet.) 

 well on the flank, while the bases of the very stout pelvic 

 fins {ph\) are seen on tlie somewhat fiattened ventral aspect 

 slightly further back. Each of the latter comprises at least 

 eight or nine robust rays, of which only the undivided 

 proximal ends are preserved. The anal fin (a.) is small, 

 arising about midway between the pelvic and caudal fins. 

 The cycloidal scales are rather thick, and merely exhibit the 

 concentric lines of growth without any posterior creaulations 

 or serrations. 



Comparing the specimen now described with those in tiie 

 British Museum which were referred to AuloJepis ti/pus in 

 1895, it is evident that only those numbered 47932 and 

 P. 4247 were rightly determined. Nos. 49903, P. 1854, and 

 P. 5681 probably belong to a small species of Osmeroides, 

 which will be discussed in part iv. of the British Museum 

 * Catalogue of P^ossil Fishes.' It now appears that the skull 

 of Aulo/e/As is intermediate in characters between that of the 

 typical Elopidaj and that of the typical Clupeidge. The 

 supraoccipital bone enters the cranial roof, though not com- 

 pletely separating the parietals, while the lateral muscles of 

 the trunk must have extended well forwards over the sides of 

 the skull above the laterally projecting otic region. There is 

 no evidence of a gular i)late ; indeed it was probably absent, 

 for the branchiostegal rays are distinctly few in number. 

 The jaws are typically Clupeoid. The trunk is compara- 

 tively short, much laterally compressed, and covered with 

 rather large cycloid scales, while the fins are exactly as 



