84 



PISCES 



CLASS I 



Ptycholepis, Ag. Head and opercular bones ornamented with ridges of 

 ganoine ; teeth minute. Scales thick, much longer than deep, externally 

 marked with longitudinal grooves. P. bollensis, Ag., from Upper Lias of 

 England, France, Bavaria, and Wiirtemberg. Other species in Lower Lias of 

 England. Smaller species in Trias of Raibl, Carinthia, and Connecticut. 



extending 



Family 4. Macrosemiidae. 



Marginal teeth styliform ; dorsal fin elongated ; scales rhombic. 



Ophiopsis, Ag. Trunk much elongated and slender, with a high dorsal fin 

 half its length. Anal fin small. Caudal fin hemi-heterocercal. 

 Ranging from the Muschelkalk to the Purbeck Beds. 0. procera, Ag., and 

 other species common in the Lithographic Stone of Bavaria. 



Macrepistius, Cope. Lower Cretaceous ; Texas. Eusemius, Vetter. Upper 

 Jura ; Bavaria. 



Notagogus, Ag. Trunk elongated, with extended dorsal fin subdivided into 

 two parts, the anterior portion with comparatively widely spaced rays, and 

 not deeper than the posterior portion. Stout ring-vertebrae. N. penilandi, 

 Ag., from Neocomian, Castellamare, near Naples. Other species in the 

 Lithographic Stone of Bavaria. 



Propterus, Ag. As Notagogus, but trunk deeper and anterior portion 

 of dorsal fin deeper than posterior portion. Ring-vertebrae. Scales almost 



six-sided, deeper than long. Jura. 



Histionotus, Egerton. The back of the 

 elongated trunk elevated and sharply bent 

 anteriorly, a single long dorsal fin extend- 

 ing backwards from the bend almost to 

 the caudal fin, which is deeply forked. 

 Uniserial fulcra on both paired and median 

 fins. Scales of flank deeper than broad. 

 H. angularis, Eg., from the English Purbeck 

 Beds. Other species from the Lithographic 

 Stone of Bavaria and France. 



Macrosemius, Ag. (Disticholepis, Thioll.), 

 (Fig. 150). Trunk elongated, and dorsal 

 fin extending from the occiput to the 

 caudal fin, which is rounded. No fin 

 fulcra. Jaws and pterygoid with power- 

 ful conical or styliform teeth. Scales 

 thin and rhombic. M. rostratus, Ag., M. latiusculus, Wagn. (Fig. 150), and 

 other species in the Lithographic Stone of Bavaria and France. Small 

 species of this or an allied genus in the Purbeck Beds of Wiltshire and 

 the Portlandian of Meuse, France. 



Petalopteryx, Pictet. Upper Cretaceous ; Mount Lebanon. 



Fig. ]50. 



, nat. size. 

 Kelheim . 



Macrosemius latiusculus, Wagn. Hea 

 Upper Jurassic (Lithographic Stone) : 

 ar, Articular ; br, Branchiostegal rays ; cl, Clavicle ; 

 d, Dentary ; hy, Ceratohyal ; mx, Maxilla ; o, Orbit ; 

 op, Operculum ; pa, Parietal ; pi, Palatine ; pmx, 

 Premaxilla ; pop, Preoperculum ; psph, Para- 

 sphenoid ; pt, Pterygoid ; qu, Quadrate ; sop, Sub- 

 operculum ; spl, Splenial ; vo, Vomer. 



Family 5. Pholidophoridae. 



Trunk fusiform ; teeth small and conical; scales rhombic and deeply overlapping ; 

 dorsal and anal fins small ; vertebrae forming complete rings. 



Pholidopleurus, Bronn (Fig. 151). Trunk slender. Scales smooth, one 



