Apateolepis australis, sj). nov. 
PL IV, Figs. 1-4. 
Obs . — All the examples of Ai'xiteolepis hitherto met ivith in the 
Ilawkeshury hods are referable to a single species, o£ which the following 
specimens exhibit some of the principal characters : — 
{a) Nearly complete fish, wanting the paired lins, shown of the 
natural size in PI, IV, Pig. 1. (Type specimen.) 
{h) Imperfect fish, viewed in part from the ventral aspect, displaying 
portions of all the fins, and shown of the natural size in PL 
IV, Pig. 2. 
(c) Specimen in connterjiart, showing the greater portion of the fish, 
with remains of all the fins, and faint indications of long 
slender neural arches and spines, 
{(1) Tail, shown of the natural size in PI. IV, Pig. 8. 
{e) Pragment showing flank-scales, of which some are enlarged six 
times in PI. IV, Pig. 4. 
General Form . — The type-specimen measures about 0’18 in total length, 
and about 0'03 in maximum depth, the trunk being thus comparatively 
slender, and more than four times as long as the head with the opcn’cular 
apparatus. The upper lobe of the tail is much elongated, though robust. 
The dorsal fin is placed over the posterior portion of the pelvic pair, and well 
in advance of the anal. 
Head and Opercular Apparalm . — That the head is typically that of a 
Palceoniscid is evident; hut no precise details of structure are caj)ahle of 
determination. In the type-specimen (PL IV, Pig. 1), an element of the 
upper jaw is faintly indicated, and may probably he regarded as the pterygo- 
palatine arcade {pt. pi .) ; and in the same fossil, the mandible is imperfectly 
shown, being probably somewhat broken in front and artificially deepened by 
crushing. A longitudinally-striated element, evidently the dentary {d), is 
recognizable ; and there are traces of minute teeth in both jaws. The oper- 
culum {op.) is small, quadrangular, and irregularly rhomhoidal in form ; and 
the suhoperculum {s. op.) is a somewhat larger hone, exceeding the oper- 
culum in breadth, if not also in depth. 
Axial Skeleton of Trunk . — In most examples of A. australis, there is 
distinct evidence of the persistence of the notochord, and in some specimens 
