BY J. DOUGLAS OGILBY. F 
the spiracles. A group of small blunt tubercles above each 
spiracle, from which a more or less extended series curves 
forward along the supraciliary edge ; a transverse row of 
three tubercles behind the occipital depression, from behind 
the middle one of which a series of retrorse spines extends 
elong the dorsal ridge and is continued on the tail nearly 
to the base of the caudal spine ; one of the median inter- 
scapular spines is slightly larger than the others of the 
vertebral series; entire scapular region tuberculigerous, 
the central group quinqueradiate, one branch directed 
forwards along and converging on the axial series, two 
directed outwards to a level with the spiracle, and two 
directed backwards, but somewhat divergent from the 
axis ; on either side between the basal angles of the outer 
and hinder branches are two or three enlarged tubercles. 
Length of tail 24+ times that of the disk ; spinous tubercles 
of tail, especially the four nearest to the caudal spine, 
larger than those of the dorsal ridge ; sides of tail with a few 
scattered prickles; proximal portion of caudal spine 
laterally granulated, the rest, with the exception of the 
extreme tip, which is smooth, armed with fine, closely set 
serre ; length of spine 3 of that of the prespinous portion 
of the tail, which is 53 in the length of the tail. A short 
fold, highest posteriorly, on the upper surface of the tail, 
overlapped in front by the caudal spine ; lower surface 
of tail with a much longer and slightly higher fold, which 
originates below the base of the caudal spine. Olive-brown 
above, the margins of the disk and the ventral fins lighter ; 
below bluish white with the discal borders pale brown ; 
tail black, the lower surface and sides of the proximal 
fourth brown; spine and tubercles whitish (fluviorum, of 
the rivers). 
Measurements of type in millimeters. 
Length from tip of snout to end of anus 250; width 
of disk 275; length of ventral fin along outer border 60 ; 
width of mouth 27; between outer anterior angles of 
nostrils 28; diameter of eye 103; width of interorbital 
region 30; length of tail 544. 
, Brisbane River, ascending well above the tideway. 
