5 
tlio fossil tectli originally termed Ceratodm^ , truly pertain to tlic fish now 
descrilied. Tliouglv an imperfect tail of the early Mesozoic Ceratodus has 
already heen made known, t and a toleraldy complete skull hrielly noticed, | 
there is yet no decisive proof of the generic identity of the extinct and living 
species ; and future discoveries may thus eventually relegate Gosfordia to 
the synonymy of Ceratodus proper, and justify the adoption of a new name 
for the existing hsh of the Queensland rivers. 
GoSrORDIA TRUNCATA, Sp. nOK. 
?1. I; PI. n, Figs. 1, 2. 
Ohs. — Of tliis genus and species no complete fisli is knoAvn ; Init, in 
addition to less satisfactory fragments, tlie following series of specimens 
cxhiliits many of the chief features in its skeletal anatomy : — 
{a) Head and anterior portion of tlie trunk, shown of one-half the 
natural size in PI. T, Pig. 1. 
{h) The greater portion of the trunk to tlie ti]> of the tail, shown 
of onc-half the natural size in PI. II, Pig. 1. This and the 
preceding arc the type-specimens. 
(c) A portion of the axial skeleton of the trunk. 
{d) Terminal portion of the trunk, Avith the median lln and one of 
the pelvic pair, shoAvn of the natural size in PI. I, Pig. 2. 
(e) Pragment, Avith fin-rays (PI. II, Pig. 1). 
General Form. — The head is remarkably small and triangular. 
Immediately heliind it, tlie triiuk rapidly deepens, and in the original of 
PI. I, Pig. 3, the maximum Avidth of the crushed head (0d)8) hecomes no less 
than 0T9 at a point 0‘17 distant nearer the tail. The total length of a fish 
of these proportions is probably not less than O'G, and its lateral compression 
is indicated by tlie iiwariable display of a side- vie av in the fossils. 
Head and Opercular Apparatus. — The . only specimen exhihiting the 
head (PI. I, Pig. 1), is in a A'ery imperfect state of presentation, and does not 
admit of the determination of any structural features. Its relatively small 
proportions, hoAvever, are Avell shoAvn. A faint groove and ridge {x) mark 
* L. Agassiz, Rech. Poiss. Foss., 1838, A'ol. iii, j). 129. 
t Ca'lacanf/ms ijiganfens, T. C. AVinkler, Archiv. Miis. Teyler, 1880, A"ol. v^, pp. 141-147, PI. ix. 
7 n. vStur, “ A'orlago des ersteii fossileii Scliiidels von Ccratodm ans den o1)eitriasisclien Rcingrabncr 
Sohiefern von Pulzberg ndrdlich boi Lunz,” A"eih. k.k. (icol. Reichsaiist. Wien, 188(i, pp. .381 383. 
