OSTRACION UNDECIM-ACULEATUS.— Smith. 
Pisces. — Plate XVII. 
O. supra lucide ochraoeus ; infra stramineus ; pinnis subocliraceis ; figura quadrangulare, angulis aculeis 
armatis, quinque dorso, sex abdominis lateribus; fissura brancbiale angulata. 
Lodgitudo a nasi apice ad extremitateni pinnae caudalis C unc. 
Colour.— Back and sides intermediate between ochre and straw-yellow, 
the tint clear and semipellucid ; below straw-yellow or pale cream-yellow ; 
fins the same colour as the back, only paler and without the lucid hue. In 
many specimens the upper and lateral parts of the head and the lower 
portions of the sides over the abdominal angles irregularly tinged with a dull 
orange-coloured brown. 
Form, &c. — Figure quadrangular ; the superior or dorsal side much 
narrower than the inferior or abdominal side, and the lateral sides, in 
regard of breadth, intermediate between the two. The angle at each side of 
the back, formed by the junction of the dorsal and lateral sides, nearly 
straight anteriorly, posteriorly convergent, and behind the dorsal fin forms 
with its fellow of the opposite side a flat triangular and obtuse point, which 
projects over the upper surface of the tail. The breadth of the dorsal side is 
greatest at the points where the angles begin to converge, and each point is 
armed with a short, pointed, horizontal spine. Besides those spines there are 
three others on the back, one projecting anteriorly from each superciliary 
ridge, and one about midway between the two first-mentioned, near the 
centre of the back in front of the dorsal fin. Top of the head level 
posteriorly, concave anteriorly, the concavity broad between the eyes, narrow 
towards the liindhead ; the sides of head under the eyes compressed ; face 
moderately broad and rounded, muzzle rather produced and projecting 
slightly beyond the general slope of the face. Branchial opening angular, 
and situated some distance behind a line let fall from the outer corner of the 
e V e. The lateral sides of the cuirass, which are slightly waved, diverge 
from above downwards, and the abdominal angles, formed by the lateral and 
under sides of the cuirass, anteriorly obtuse, posteriorly acute, and each 
is armed with three short spines, the first situated about midway between 
the nose and hinder extremity of the cuirass, the last at the extremity of the 
latter and the third about equidistant between these two : the direction 
