FISHES OF CEARA, BRAZTI, JORDAN AND BRAXXEK 



13 



Lcpi dotes 

 tcmnnrus. 



bent downward in the middle, the head is entirely crushed, and the 

 dorsal, anal, and tail are absent and the pectoral fin broken (fig-. 6). 



The head was about 35^ times in length to base of caudal, the 

 greatest depth over the ventral fins about 3§. The scales are rhom- 

 bic, entire, deeply overlapping, most of them deeper 

 than long. The surface of the scale is not smooth, 

 but marked with about three coarse ridges, parallel 

 with the anterior margins. The distance of the 

 ventral from the head is apparently a little more than 

 length of head. The ridge scales on the back are 

 very distinct, spine-like, more elevated than usual 

 in Lcpidotes. Three are distinct behind the nuchal 

 region, and there are traces of others farther back. 



In the description of Lepidotiis maivsoiii it is pxc.. 7. Scale of 



stated that the principal flank scales are "with fre- 

 quently discontinuous enamel marked with a few 

 broad ridges and furrows radiating from the center to the hinder 

 border, where they form feeble indentations." The markings on 

 L. tcmnurus do not answer to this description. 



Family LEPTOLEPID.E 



This family stands almost intermediate between the Ganoids and 

 the Isospondyli. It has the general fin arrangement of the latter, 

 but the scales are more or less diamond-shaped and ganoid on their 

 exposed parts, and the last vertebrae are more or less turned upward, 

 although the tail is usually or always forked. The orbital plates 

 cover the cheek as in the Elopidae, but there is no gular plate, so far 

 as known. 



Genus THARRHIAS Jordan and Branner, new genus 



A species from Ceara is referred by us to the family of Lepto- 

 lepidse, and it is very closely allied to the typical genus, Leptolepis, of 

 the Triassic and Cretaceous of Europe. It is, however, distinguish- 

 able by the much larger opercle, which is more than four times as 

 deep as the subopercle and separated from it by a horizontal suture. 

 The vertebrae are 50 to 55 in number, while the type of Leptolepis^ 



^Leptolepis Agassiz, Neues Jahrbucli 1832, p. 146; type, Leptolepis bronni 

 Agassiz (1832), Cyprinus corypcenoides Bkonn (1830). 



Ascalabos von MtJNSTER, Beitr. Petrsfakt, i, 1839, p. 112; tj-pe, Ascalabos 

 voithii VON Munster. 



Tharsis GiEbEL, Fauna der Vorwelt, Fische, 1848, p. 145 ; type, Tharsis 

 radiatus Giebel. 



Sarginites Costa, Alte. Acoad. Pontan. v. 1850. p. 285 ; type, Sarginites 

 pygmccus Costa. 



Megastoma Costa, 1. c, 1850, p. 287; type. Megastoma apenninnm Costa. 



