32 
ACTINOPTERYGII. 
Rhacolepis latus, Agassiz. 
1841. Phacole2)is latus, L. Agassiz, Edinb, New Pliil. Journ. toL xxx. 
p. 83. 
1844. Phacolepis latus, L. Agassiz, Comptes Rendiis, vol. xviii. p. 1012, 
and Poiss. Foss. vol. iv. p. 293 (name only). 
1887. Phacolepis latus, A. S. Woodward, Proc. Zool. Soc. p. 539, 
pi. xlvii. fig. 5. 
Type. Imperfect small fish ; British Museum. 
An imperfectly known small species with much-deepened trunk. 
The two posterior suhorhitals a little broader than deep, and the 
postero-inferior suborbital of a deep triangular form; operculum 
about twice as deep as broad. Pelvic fins arising about midway 
between the pectorals and the anal, opposite the anterior half of the 
dorsal. 
Form. Loc. Upper Cretaceous : Province of Ceara, N. Brazil. 
P. 1959, P. 3984. Type specimen, in counterpart, described and 
figured loc. cit. 1887; Barra do Jardim, Serra de Araripe. 
Eyevton ^ Enniskillen Colls. 
28616 C. Trunk doubtfully referred to this species, showing enlarged 
and elongated anterior dorsal fin-ray. Purchased, 1853. 
15493. More imperfect similar trunk. 
Purchased from Mr. Gardner. 
Genus THRISSOPATER, Giinther. 
[Pigs. & Descript. Brit. Organic Bemains, dec. xiii. 
(Mem. Geol. Surv. 1872) no. 1.] 
Trunk somewhat laterally compressed; abdomen compressed to 
an edge. Parietal bones small and separated by the supraoccipital; 
a deep quadrangular median pit in the cranial roof in the hinder 
part of the frontal region; maxilla slender, with one supramaxillary 
bone; mandible a little prominent, and gape extending to the 
hinder border of the orbit; margin of the jaws with a single series 
of small conical teeth. Operculum simple; opercular bones and 
clavicular plates slightly dilated and smooth; branchiostegal rays 
about 30 in number. Vertebrae about 50 in number, the centra 
slightly constricted, smooth or delicately ridged. Pectoral fin with 
an enlarged and elongated scale at its base ; pelvic fins opposed to 
the dorsal; anal fin relatively small; caudal fin deeply forked; no 
