7. MYBinUSTIS. 23 



arc three-foui'th.s as long as the maxillary, and have a slight pro- 

 minence behind. The mandibularies are rather short and high ; 

 each is distinguished by a small i)rotuberance in front. 



The dentition is chiefly formed by broad bands of fine villiform 

 teeth ; at several places are small, short, granular prominences, 

 .similar to those of the angle of maxillary, and more hke apophyses 

 than true teeth. Such granulations may be seen strongest in front 

 of both the jaws, on the protuberances of the boiies, but moreover 

 also on the outer edges of intermaxillary and mandibulaiy. The 

 band of the upj^er jaw is nearly t'W'ice as broad as that of the dentary 

 bone ; both reach to the extremities of their bones. All the other 

 teeth are exceedingly fine and velvet-like ; those of the vomer form 

 a triangular patch uith concave sides, those of the palatines a cunei- 

 form band, broad anteriorly, and do not extend beyond that bone. 

 The teeth of the pharj^ngo-branchials are placed in an ovate group 

 with several smaller ones besides. 



The infraorbital arch is rather narrow and nearly equally broad, 

 the prajorbital not being Avidened on account of the shortness of the 

 snout. It is transformed into a bony half-channel, the open side of 

 which is covered by a thin membrane, and the edges of which are 

 finely serrated. The arch has inside a naiTow, concave, and thin 

 plate for supporting the eye-ball from beneath. The entoptenjejoid 

 is very broad, and attached to the basisphenoid by a naiTow ligament 

 only, so that the bottom of the orbit is nearly entirely bony. 



All the opercles are distinctly striated as far as they are not covered 

 by scales. Tlie operculum is more than twice as high as wdde ; on 

 its upper third it has a flat ridge terminating in a distinct point, 

 above and below which is a slight notch ; the serrature is fine, but 

 distinct. Tht, subopercidum is narrow, with a shallow notch before 

 the pectoral fin, and three or fom* very slight denticulations beneath. 

 The interoperculum is two and a half tis long as high, distinctly, but 

 more finely serrated than the oi)crculum, and has a convex lower 

 margin. The pi"a)opercukim is distinguished by two nearly parallel 

 serrated edges ; the posterior pau' is finely serrated, like the inter- 

 operculum, the scrratiu'c of the supplementary ridge being rather 

 indistinct ; the inferior pair has both the edges equally and finely 

 serrated. Both the pairs ineet at a rather obtuse angle, and here the 

 serrature is somewhat stronger and more like that of the opereulura. 



The skull of Mi/ripristis shows the remarkable peculiarity of a 

 large oval opening, closed by an elastic membrane — an internal tym- 

 panum. The opening appears to belong to the alisphenoid bone ; 

 at the bottom of the cavdty is placed a large otoHth. The membra- 

 naceous cover is in immediate connexion with the lobe of the anterion 

 part of the air-bladder, and atta(;hed to it is an elastic, bony, ex- 

 cavated plate, in form similar to the tragiis of the common Bat, and 

 arising from the lower posterior angle of the opening. A similar 

 foi'm of connexion between the air-bladder and the vcstibulum is 

 found in Holocentram, Priacantlms }nacroplithahnus, Sjhv'us, Sargus, 

 Saljm, &c. 



The humeral iiviih is likewise striated and serrated, but more so at 



