74 



Membrana branchiostega aperturam amplam iegens, 

 radiis septem sustentaia. 



Pinnte reiitris caudaive nulla. Pinnce dorsi anique in 

 apicem acufissimam cmid<e coalita, radiis tenuissimis, se- 

 taceis,Jle.vilibiis susfentat(B. 



Operculum osseum stellatim tripartitum, uno ramo 

 ereclo, nliero descendenti, tertio postico, longiori, subulato, 

 subspinoso, in pisce recentl celato. Cv Anmm foi-nicatum, 

 liBve, sine carinis vel cristis. Vertebrae circit^r centum, 

 qiiarum novemdecim abdominales. 



Ventriculus magnus, ccBcatus. Intestinum bis prope 

 cesophagmn Jlexum ; ccscis pyloricis nullis. Vesicula 

 aeris ampla, longe post amim extensa. 



OxYBELES HOMEi. Richardsoii. 



Plate XLIV., fig. 7—18. 



R.ADII : — Br. 7 ; D. et A. non numerand. P. 19; C. 0. 



The specific name is intended as a tribute of acknow- 

 ledgement to the zeal of Sir Everard Home in collecting 

 objects of Natural History on the coa.sts of China and 

 Australia. When the specimens were cursorily examined 

 before they were placed in tlie artist's hands to be drawn, 

 they appeared to represent two species, differing in the 

 relative thickness of the body, and in the commencement 

 of the dorsal fin, but on a more careful inspection after due 

 maceration in water, the characters of all three examples 

 ])roved to be nearly identical, the dissimilarity having been 

 caused by two of them being placed in strong spirits, 

 whereby they had become shrivelled, and a fold of skin 

 between the shoulders made to look like a forward prolon- 

 gation of the dorsal fin. This is mentioned to account 

 for two figures of the same species. 



Body stiletto-shaped, tapering, and becoming thinner 

 gradually from the head to the acute point of the tail. 

 Snout rounded obtusely ; the profile from tlie eye to the 

 shoulder slightly convex. Head thicker than the body, 

 forming one-seventh of the total length of the fi.sh. Mouth 

 terminal, cleft beyond the eye, under jaw a little longer 

 than the upper one. Upper half of the margin of the 

 mouth formed by the long, slender, non-protractile in- 

 termaxillaries. The maxillary is also slender, but di- 

 lates gradually towards its tip, which passes behind 

 the corner of the mouth. The teeth are minute, and are 

 not readily seen without the aid of a good eye-glass. They 

 are individually subulate, slightly recurved, and ranged in 

 level, villiform bands on the intermaxillaries, lower jaw and 

 edges of the palate-bones ; the dental surfaces being nar- 

 rower on the upper jaw, than on the under one or palate, 

 where they stand in four or five rows. Near the symphj'- 

 sis on both jaws a few of the teeth are higher, and two or 

 three of the anterior lateral ones in the lower jaw are tall 

 enough to merit the appellation of canines. The conical 

 knob of the vomer projects considerably, and is armed by 

 a comparatively stout central tooth, with a ring of smaller 

 ones surrounding its base. Tongue rather conical, smooth 

 and rounded. Nostrils, two orifices with tumid lips pier- 

 cing a soft membrane which occupies much of the space 



between the eye and the obtuse end of the snout. Three 

 pores stand in a transverse row between the fore parts of 

 the orbits. Preoperculum marked by a groove, which 

 crosses the top of the head, and is there perforated by 

 three pores. Cranium rounded smoothly off on the sides. 

 Gill-cover very porous, with an acute, soft tip, extending 

 beyond the subulate tip of the tripartite bony operculum. 

 Eye lateral, pretty large, bright and silvery. The gill- 

 opening extending beneath as far forward as the preoper- 

 culum. The snout, operculum and cheek are minutely 

 porous. 



Lateral line a continuous ridge standing in a furrow, 

 extending from the temporal groove to the tip of the tail, 

 and running nearer to the back than to the belly. Skin of 

 the body quite smooth. Anus situated before the pectoral 

 fin, under the upper angle of the gill-opening. An acute 

 seam or ridge runs forwards from it into the isthmus be- 

 tween the gills. M. Agassiz, to whom I showed the spe- 

 cimens, informed me that this was an indication of the 

 individual's being young. Pectorals narrow and pointed, 

 having a length equal to about one-tenth of the whole fish. 

 The anal is wider than the dorsal, but both are very low, 

 and the rays cannot be very easily counted, owing to the 

 thickness of the integument and the difficulty of keeping 

 the fins extended. The fins meet in an acute point at 

 the tip of the tail, but when they are examined through a 

 good lens it may be seen that no rays emanate from the 

 apex of the tail, those of the dorsal and anal converging 

 beyond it, and leaving a minute, triangular membrane be- 

 tween. The rays are unbranched, tapering and flexible, 

 with long joints towards their lips, which can be jierceived 

 only under a considerable magnifying power, and then 

 each ray appears to have a midrib with a thin anterior and 

 posterior edge. The anterior rays are not apparently dif- 

 ferent from the others, but I have been unable to ascertain 

 clearly whether the joints are not quite obsolete in the rays 

 of the fore part of the dorsal. The dorsal begins at less 

 than a quarter of the length of the fish from the end of the 

 snout; the anal commences close to the anus, and is con- 

 sequently longer than the dorsal. 



I dissected one of Sir James Ross's specimens, but the 

 intestines were not in a very good condition for examina- 

 tion. The liver had perished. The peritoneum is thick, 

 tough, and of a shining, silvery hue, with black, star-like 

 specks. QEsophagus thin and membranous. Stomach a 

 large, conical, ca;cal sack, longitudinally plaited within, 

 with the pylorus near the oesophagus, leaving most of the 

 viscus beneath. Intestine delicate, forming two deep loops. 

 No pyloric coBca were detected. A roundish and rather 

 large spleen is attached to the posterior tip of the stomach, 

 and lies dorsad of the remains of the liver. In this indivi- 

 dual the air-bladder appeared to be a long tube, with alter- 

 nate dilatations and contractions, but in another specimen, 

 which is somewhat diaphanous, a wider air-bladder can be 

 seen running a good way behind the anus without any visi- 

 ble contractions. The vertebras amount to 99, of which 19 

 have two inferior divergent processes, affording space 

 for the viscera. The others have a single inferior and su- 

 perior process, whose tips are much compressed and very 

 thin. 



