ELOPOPSIS. 133 



base, where they are fused with the supporting bone ; mandible with a single 

 close series and an inner pair of relatively large teeth at the symphysis ; pre- 

 maxilla somewhat horizontally extended, bearing one or two relatively large teeth 

 within the marginal series of very small teeth; maxilla robust, not much arched, 

 with a single series of teeth which are smaller than those of the mandible. 

 Vertebras between 50 and GO in number, the centra not longer than deep, all 

 slightly constricted and marked with longitudinal ridges. Pelvic fins opposed 

 to the dorsal ; caudal fin forked. Scales large and delicate, deeply overlapping, 

 their exposed portion smooth or marked only with slight longitudinal strias or 

 small shallow pittings. 



Type Species. — Elopopsis frazil (Heckel, lor. cit., 1856, p. 251, pi. xiii, fig. 1), 

 represented by a nearly complete fish in the Royal Court Museum, Vienna, from 

 the Cretaceous (supposed Urgonian) of Comen, Istria. 



Remarks. — The original specimens of this genus from Comen are crushed in 

 fissile rock, and do not exhibit much of their cranial structure. More fragmentary 

 specimens from the Chalk of Bohemia, 1 Westphalia, 2 and England display parts of 

 the skull and jaws, with the dentition. 



1. Elopopsis crassus (Dixon). Plate XXVIII, figs. 2 — 4. 



1850. Osmeroides crassus, F. Dixon, Geol. Sussex, p. 376. 



1888. Osmeroides crassus, A. S. Woodward, Proc. Geol. Assoc, vol. x, p. 322. 



1895. Elopopsis crassus, A. S. Woodward, Proc. Zool. Soc, 1894, p. 659, pi. xliii, fig. 1. 



1901. Elopopsis crassus, A. S. Woodward, Catal. Foss. Fishes B. M., pt. iv, p. 10. 



1907. Elopopsis crassus, A. S. Woodward, The Naturalist, p. 306. 



Type. — Imperfect head ; Brighton Museum. 



Specific Characters. — An imperfectly known large species, the mandible attain- 

 ing a length of about 10 cm. Depth of head at occiput at least equalling length 

 of cranium. Premaxilla elongate-triangular in shape, bearing a close series of 

 small conical teeth on its oral border, and two much-enlarged teeth within, 

 these somewhat laterally-compressed but without sharp edges ; maxilla with 

 gently convex oral border, bearing a regular series of small stout teeth, slightly 

 largest on the middle of the convexity and decreasing in size backwards ; 

 mandible rapidly tapering to an almost pointed symphysis, with a series of 

 laterally-compressed, not sharp-edged teeth, which are longest just in front 

 of the middle of the ramus, and very small just behind the symphysis. The 

 teeth generally marked with a few very fine vertical stria?. 



1 Elopopsis heclceli, A. E. Reuss, Denkschr. k. Akad. Wiss., math.-naturw. CI., vol. xiii (1857), 

 p. 39, pi. iii ; A. Fritsch, Kept. u. Fisehe bolmi. Kreideform. (1878), p. 41, fig. 61. 



- Elopopsis ziegleri, W. von der March, Palaontogr., vol. xv (1868), p. 293, pi. xli, figs. 2 — 4. 



