194 TRIGLID.E. 



margin ; it is placed horizontally, forming a great portion of the 

 upi^er surface of the snout ; its anterior mai-gin is sharp, serrated ; 

 and there is a small spine, directed backwards, behind the centre 

 mentioned. The second bone is the smallest, triangular, •with two 

 sides equal, and with the lower side shortest ; the centre is situated 

 in the middle of the lower side, and there is a spine behind it. The 

 third bone is the largest, irregularly quadrangular, forming a long 

 suture with the prfeopereulum. The point from which the striae 

 radiate is excentric below the true centre, and armed with a very 

 small spine. A slight ridge, minutely serrated, runs from this point 

 to the angle of the pra^operculum. 



The prajoperculum and operculum form one continuous plane 

 with the bones cuirassing the cheek. The former has a ridge 

 across the angle, terminating in a strong spine ; there is a small 

 spine in the middle of the ridge, from which point the striae 

 radiate, with which both limbs are provided. The opercidum is 

 strongly striated, and has two ridges, terminating in spines, the 

 lower of which is the stronger. The sub- and interoperculum are 

 narrow and smooth. 



All the bones on the upper surface of the skull are rough wit?! 

 tubercular strise, radiating from the centre in each bone. The tur- 

 binal bones arc well developed, touching each other in front of the 

 ethmoid. The upper surface of the ethmoid* is quite free, sub- 

 rhomboidal, twice as long as broad, and not extending on to the 

 intcrorbital space. The prefrontals arc large, forming a suture 

 together in the median line of the skull ; theii* orbital margin is 

 armed with an obtuse point. The principal frontal bones do not 

 extend anteriorly beyond the intcrorbital space, which is concave, 

 and the width of which is less than the length of the vertical dia- 

 meter of the orbit ; they are truncated posteriorly, separated from 

 the occipitals by an indistinct transverse groove ; there is a spine on 

 the posterior portion of the orbit, from which point the striae radiate. 

 The crown of the head is flat, broader than long, and the sutures 

 between the single bones have nearly entirely disappeared, except 

 the median one. The basal portion of the brain-capsule is slightly 

 rounded ; there is a foramen in the basisphcnoid, immediately behind 

 the occipital joint. 



The suprascapula is firmly attached to the occipital, and terminates 

 in a long horizontal spine ; the scapula is oblong, broader inferiorly. 

 The coracoid is nearly straight, with two slender curved processes 

 for the junction with the scapula, and armed with a powerfid spino 

 immediately behind these processes. Each pubic bone has two 

 limbs : the anterior is formed, as in other Acanthopterygii , by three 

 lamellae, the interior of which is the broadest ; the anterior hmbs of 

 both bones converge towards the symphysis of the coracoids, leaving 

 a wide free space between them, in which there is only a very short 

 process. The posterior limb is directed inwards, emitting a long 



* An examinalion of tlio (l('vclf)pnicnt of t-lie bones of (ho skull may show that 

 this is not the othmoid itself, hut a clcnnal plate corrosponcling to the ethmoid. 



