131 



Lachnolaimus, rel Cossyphus cyanodus. Richardson. 



I.abnis ci/anodus, Richardson, Ann. and Mag. of Nat. Hist. xi. 

 p. 355. 



Radii:— B. 6; D. 1.3|7 ; A. 3|10; C. 12|; P. 15 ; V. l|5. 

 Platu LV., figs. 5—7. {L. arilca.) 



This fish wants the flexible filamentous prolongations of 

 the anterior dorsal spines, which give such a peculiar cha- 

 racter to the Lac/inolaimi of the Caribbean Sea; and it 

 differs from them in its more elevated profile, and conse- 

 quently in its general physiognomy, which is more like 

 that of Noracula, especially in the face. It has the preor- 

 bilar lips, the scaly gill-covers and cheeks, with the conti- 

 nuous lateral line, and other general characters of Lahnis, 

 but it differs from that genus in the dentition both of the 

 jaws and pharyngeals, in which it agrees with Lachno- 

 laimus. In the structure of its jaws, the upper one es- 

 pecially, it corresponds nearly with Cosayphus atrolumbiis, 

 and most likely with some others of that genus, the Cos- 

 syphi merely having the teeth on the edge of the jaw a little 

 more prominent, and those incorporated with the bone in- 

 teriorly so much developed as to render the surface granu- 

 lar. Though the vertical fins of our fish move in scaly 

 sheaths, they are much less evident than in Cossyphus, and 

 enclose only the bases of the fins. It seems to have the 

 closest aflinitj' to the Lahrtis macrodontus and Japouicus, 

 and to the Cossyphus schwnleinii of the Histoire des 

 Poissons, diff'ering from them rather in specific characters 

 than generic ones, and agreeing with them in dentition 

 and in the number of the fin rays.* 



This fish obtains the names of" 'nguvmin" and " arilka" 

 from the native tribes in the vicinity of Port Essington. 

 The specimen we have figured was taken in Endeavour 

 Straits, on the reef which surrounds Bramble Island. 



The profile of the snout rises at an angle of 45°, with a 

 slight concavity opposite the preorbitars, and a convexity 

 at the nostrils, where it begins to round gradually over 

 the eye into the nearly horizontal curve of the nape. 

 Along the whole extent of the dorsal, the outline of the 

 back descends to join the concave sweep of the trunk of 

 the tail. The outline of the belly wants the bold convex- 

 ity of the forehead and nape, but is otherwise nearly simi- 

 lar to the dorsal line. The height of the trunk of the tail 

 exceeds one-third of the greatest height of the body, and 

 its length between the dorsal and caudal is nearly one- 

 sixth of the total length of the fish. 



The length of the head is contained thrice and two- 

 thirds in the length of the fish, and its height is not above 

 a ninth or tenth part less than its length. The eye, of a 

 moderate size and round, is situated above the level of the 



* See also Cossyphus cyannstolus and onunoplcrns of ' The Report on 

 the Ichthyology of China,' p. 256, 257, which agree generically with the 

 species named above, and in the numbers of the rays. Labrus reticula- 

 ris of the Fauna Japonica has a different number of dorsal rays, but si- 

 milar construction of the jaws with the other species of this group. 



angle of the gill-cover, having a very high cheek and in- 

 teroperculum beneath it, and a large preorbitar descending 

 obliquely before it. It is two diameters of the orbit from 

 the end of the snout, and rather farther from the tip of 

 the gill-cover. The nostrils arc very small simple ojjcn- 

 ings, situated nearer to the eye than to the edge of the 

 snout. The preorbitar lip is wide, and contiiuious over 

 the premaxillary pedicles and cheek, forming a covering 

 for the whole of the maxillary and the outer half of the 

 premaxillary when the jaws are retracted. The obtuse 

 end of the maxillary just appears at the corner of the 

 iiiouth when the jaws are extended. The premaxillary 

 lips are full and plaited, and the mandibular one folds 

 back on the limb of the jaw. The gape of the mouth 

 is low down, and scarcely extends as far back as the 

 anterior nostril. The mandible when depressed is equal 

 in length to the premaxillary when fully protracted, and 

 ascends a little when the jaws are retracted. The preraaxil- 

 laries are moderately protractile : each is armed anteriorly 

 by two strong canines, the one next the symphysis being 

 the largest : they are conical, slightly curved, directed for- 

 wards and downwards, and both are closely incorporated 

 with the bone, so that there appears to be no line of sepa- 

 ration between the root of the tooth and substance of the 

 bone. The jaw interiorly is naked and polished, as if 

 worn or enamelled, for a considerable breadth, and its 

 edge, which is rather obtuse throughout, is a little swollen 

 behind the canines ; and close to the symphysis there is a 

 small conical tooth immediately behind the largest canine, 

 and two or three minute granular ones appear as if passing 

 out of the bone on the lateral edge of the jaw. The man- 

 dible exhibits the same polished edge and interior surface 

 as the premaxillary, and is also armed with two stout ca- 

 nines directed forwards and upwards. There is no small 

 interior conical tooth at the symphysis, but a series of very 

 small granular teeth on the edge of the jaw is visible to 

 the naked eye, particularly two or three of them behind its 

 middle. There is no canine at the corner of the mouth. 

 The upper pharyngeals (fig. 6) are two small bones with 

 flat granular disks, and the teeth shining through, as on 

 the jaws of a Scar us. The teeth and jaws are greenish. 



The cheek is protected by small, remote, round scales, 

 forming five or six rows between the orbit and curve of the 

 preopercular disk. There are six in a single series on the 

 interoperculum, and the operculum and suboperculum are 

 covered by six rows of larger ones closel}' tiled. The disk 

 of the preopercuhim is naked, and the interoperculum is 

 very broad, its edge being membranous. The gill-cover is 

 also bordered with smooth membrane, beneath whose edge 

 the rather narrow gill-membrane folds. The rays of the 

 latter are long, slender, curved and flexible. The tip of 

 the gill-cover is a rounded lobe, rendered more prominent 

 by a wide curve narrowing the suboperculum. 



The lateral line is traced on twenty-nine or thirty scales, 

 the last two of which are as large as the others, and sheath 

 the base of the caudal rays. The exposed disks of the 

 scales are without striae; their bases are marked by twenty- 

 five or thirty, diverging in a fan-like way. The scales 

 forming the lateral line have each a long tube, with six or 

 seven spreading divisions at the end. On the posterior 



