LAM PR IS LAUTA. 



31 



breadth of their base. The anormal number of their rays, sixteen or seventeen, 

 and want of a true spine, are very peculiar characters. 



The caudal fin is simply forked, not lunate, large and powerful. Its forks are 

 broad, but considerably shorter than in MM. Cuvier and Valenciennes's fish ; 

 being only about one fifth, instead of one third, of the entire length of the fish. 

 They are furnished outside with a number of short accessory simple rays, enclosing 

 a broad, rounded, fleshy space. The longest of these reaches to the tip of each fork. 

 The seventeen rays within are copiously branched. 



The rays of all the fins are of a substance between cartilaginous and horny ; and 

 are curiously compressed, or as it were, planed flat, on each side ; the first long 

 unbranched ray of all the fins, except the anal, has the front edge sharp, the 

 hinder edge flat or grooved, and the sides very broad : the whole resembling a 

 scimitar. The other rays of the pectoral, ventral, and caudal fins, and the hinder 

 ones of the dorsal and anal, are branched dichotomously in a peculiarly gi-aceful 

 feathery manner : and so copiously towards the hinder ends of the two first and 

 last, and in the middle of the caudal fin, that the web is quite obliterated. 



The scales are small, and soft, or membranous and satiny ; extremely decidu- 

 ous, or rubbing off almost with a touch : hence the more prominent parts, espe- 

 cially the throat, breast-keel, and corresponding ridge of the back are smooth and 

 naked. The head, cheeks, and all the opercles are, however, scaled all over. 



The muzzle, lips, and maxillaries, the dorsal, anal, pectoral, and ventral fins are 

 smooth and naked ; the caudal fin alone has rows of very bright silver scales, 

 running a considerable way up between the rays. 



The lateral line rises at once steeply at its origin ; forming an abrupt high arch, 

 under the high fore-part of the dorsal fin, approaching near to the ridge of the back. 

 It then descends, at first abruptly, afterwards more gradually ; attaining the mid- 

 dle of the body at about the middle of the dorsal, or beginning of the anal fin ,• and 

 thence continues in a straight line to its termination. Though sufficiently dis- 

 tinct throughout, it is in no part keeled ; and not more elevated towards the tail 

 than forwarder, being formed by short raised lines or marks upon the skin, which 

 are more obvious when the scales are removed. 



The coloLU's are truly splendid. When quite fresh and uninjured, the whole 

 body appears covered with a rich brocade of silver and rose or lilac, formed by the 

 scales, reflecting on the middle of the sides golden tints ; but pure silver and rose- 

 lilac on the back, silver and more rose than lilac on the belly. The whole sides, 

 cheeks, and opercles, are spotted with round and oval pale or silvery whitish spots, 

 shining through the scales ; becoming towards the throat and sides of the breast 

 or belly, irregular and confluent, forming waved mosaic marks or bands. The 

 raised sides of the groove embracing the base of the dorsal and anal fins, and the 

 rows of imbricated scales running up between the rays of the caudal fin, are 

 bright pure silver. The head, opercles, and back reflect bright iridescent ultrama- 

 rine tints. 



On removing the scales, or where they have been worn away by rubbing, the 

 skin is in general of a very dark rusty grey, approaching to black, with a dark 

 bottle-green tinge on the top of the head, shoulders, and forepart of the back, the 

 white spots appearing clearer and brighter silver than before. The naked keel of 

 the breast and throat is dark rose-colour mottled with brownish-black. 



The naked muzzle before the eyes, the lips, and lower jaw are rich vermilion. 

 The upper lip and top of the muzzle are tinged with olive-brown ; the lower lip 

 and jaw beneath blend into white. The tongue is white, tinged with vermilion. 

 The ends of the maxillaries are silvery. 



The iris is clouded with gold and vermilion on a silver ground ; the pupil is a 

 bluish-black. The edges of the orbits are dusky brownish. 



