272 



ICHTHYOLOGY. 



Classifica- market, which amount, according to the same authority, to 



tion- 



Fishes. 



_ 3,000 in a season. Pennant lias particularly described the 

 ^an op- gxtensive Turbot fishery at Scarboroufjh. There are three 

 men in each of the fishing-boats, each man having three 

 lines, and each line 280 hooks. All the nine lines are fas- 

 tened together, and then extended to about three miles in 

 length ; they are laid across the current, and are allowed to 

 remain for six hom's before they are hauled in. This fish is 

 called the Water or Sea Pheasant, by the Prench common 

 people, on account of its fine flavour. 



Family IV.— PLKCTRONECTID^. 



Peculiar among fishes in showing a want of symmetry in the 

 head, the eyes being turned to that side, which is uppermost when 

 the animal swims, and is always darker-coloured than the other 

 side. Body extremely compressed, so that the ventral and dorsal 

 aspects are mere edges, the sides forming disks, round, oval, ovate, 

 or elliptical, differently coloured, the paler one simulating the 

 belly, and being beneath in the usual position of the fish. Dorsal 

 extending along the whole back, and in some running forwards to 

 the nostrils; anal fringing in the sam (way the ventral edge ; jaws 

 and ventrals generally unsynmietrical, being smaller on the pale 

 Bide. Branchiostegals six. The presphenoid is twisted to one side, 

 and the mid-frontal is one of the most distorted bones in the cra- 

 nium of these fishes. There is no want of symmetry in the spinal 

 column and its processes posterior to the scapular arch ; the inter- 

 neural and interhfemal spines are in pairs, supporting one dermo- 

 neural or dermohaemal spine. No air-bladder. 



ANALYTICAL TABLE OF THE PLEURONECTIDJE (Dum.) 



Body rhomboidal. 



Dorsal over the eyes which are dextral. 



Teeth broad, trenchant Platessa 1. 



Teeth villiform HipPOGLOSSUS 2. 



Dorsal over the upi>er lip ; eyes sinistral Rhombus 3. 



Body oval, or much elongated. 



Pectorals very distinct^ on both sides SOLEA 4. 



Pectorals distinct on one side only MONOCHIR 5. 



Pectorals wanting. 



Vertical fins separated ACHIRUS 6. 



Vertical fins united Plagiusa 7. 



Genus I. Platessa, Cuv. Obtuse, trenchant, uniserial teeth on 

 the jaws; most frequently pavement-like teeth on the pharyngeals. 

 Dorsal not coming further forward than the centre of the upper 

 eye ; caudal separated by intervals from the dorsal and anal. Form 

 rhomboidal. Kyes generally on the right side. Pancreatic caeca 

 three, small. 



Genus II. IIirpooLOSsus, Cuv. Fins of Platessa, with gene- 

 rally a more oblong form. Teeth card-like, often strong and 

 pointed on the jaws and pharyngeals. 



Genus III. Kmombus, Cuv. Teeth on the jaws and pharyngeals 

 villiform, or card-like, as in Hippoglossus, but the dorsal comes 

 forward to the border of the upper jaw, and extends like the 

 anal to near the caudal. Eyes for the most part on the leftside. 



Gfnus IV. Solea, Cuv. Mouth curved and turned almost 

 wholly to the blind side of the head ; teeth situated on that side 

 only, finely villiform ; form oblong ; snout round, and almost always 

 advancing before the mou'h. Dorsal commencing at the mouth and 

 extending like the anal to the caudal. Lateral line straight. Blind 

 side of the head often garnished with cutaneous shreds like villi. In- 

 testine long, often doubled ; no pancreatic ca;ca. In some the caudal 

 is not distinct from the other two vertical fins. These form the 

 genus Brachirus of Swainson, or Synaptura of Cantor. 



Genus V. MoNocmit, Cuv. Sofcs destitute of a pectoral on the 

 blind side, or having merely an almost imperceptible vestige of one, 

 the pectoral on the side of the eyes being very small. 



Genus VI. Achiuus, Lacep. Abrachial Soles, with the vertical 

 fins distinct. 



Genus VII. Plagusia, Brown. Abrachial Soles, with the ver- 

 tical fins united. 



Order V.— ACANTHOPTEROUS FISHES. ■ 



This order, the most extensive of all for the variety of 

 forms and number of species, includes fishes under every 

 condition that a fish can exist, whether it be with regard to 

 the freshness or saltness of the water it inhabits, its tem- 



perature, depth, altitude above the sea, or other circum- Classifica- 

 stances. There is certainly some connection between the ""^ — 

 ciliated scales with which the great majority of fishes of this -'^^''"'^"'P- 

 order are clothed, and the spinous terminations or serrated pjshes 

 edges of many of the bones of the head and shoulder which \ ^ '/ 

 appear on the surface, and assume more or less the condi- 

 tions and functions of dermal productions. The ctenoid 

 scale, however common it may be in the order, is not uni- 

 versal, and the first family, the Uranoscopes have chiefly 

 cycloid scales. The absence of a pneumatic tube to the air- 

 bladder is perhaps a more constant character, but the viscus 

 itself is not always present. The ventral fins are, when 

 they exist, placed, in the majority, near the pectorals- 



Order V.— ACANTHOPTERI, Mull. 



Endo-skeleton ossified ; exo-skeleton as ctenoid scales. Fins with 

 one or more of the first rays unjointed or inflexible spines ; ventrals 

 in most beneath or in advance of the pectorals. Swim-bladder 

 without air-duct. 



URANOSCOPID^. 



The Uranoscopes are remarkable for their power of raising 

 their eyeballs out of their sockets, and of retracting them 

 again within the level of the orbits. They frequent the 

 bottom of the sea, and, like many ground fish, some of them 

 have organs of touch developed in form of barbels, and 

 they have also a peculiar membranous filament under the 

 tongue, which they can protrude at pleasure. The Medi- 

 terranean Uranoscope was named Affiuis and Callionymus 

 by the ancient Homans, and Pliny says that the same fish 

 was called Culliom/mus antl Vranoscopus. Aristotle re- 

 marks correctly that the gall-bladder of this fish is attached 

 to the right lobe of the liver, and is of greater size than in 

 other fishes; and the dramatic poets referred to it proverbi- 

 ally when alluding to an angry man. Its gall was supposed 

 to have some power of rendering the sight more clear, of re- 

 moving deafness, and of depressing the fungus growths of 

 old sores. The species are more numerous in the Australian 

 seas than in any other quarter of the ocean. Trachintis 

 has some resemblance in external characters to the Sclcro- 

 genidoB, especially in the simplicity and thickness of the 

 lower pectoral rays, and in the projection of the tips of the 

 anal rays beyond the membrane, but they are distinguished 

 by the second suborbitar not crossing the cheek to the pre- 

 operculum. The Uranoscopes, indeed, make an approach 

 to this peculiar structure, but in them the suborbitar articu- 

 lates with the upper limb of the preoperculum, and does 

 not buttress its angle, as in the true Sclerogenids. The pro- 

 jecting tips of the anal rays occurring in many ground 

 fishes are seemingly organs of touch. The family gene- 

 rally, as here assembled, corresponds with Cuvier's group 

 of Jugular Percoids, but we have brought into it Hemero- 

 ccetes, which is placed at the end of the Gobioids, next Cal- 

 lloiiymiis, in the Histoire des Poissons, and also an Aus- 

 tralian fiesh-water genus Gadopsis not described in that 

 work. The internal structure of several of the genera must 

 be investigated before the correctness of this grouping can 

 be ascertained. None of the family are of importance as 

 articles of food. The woodcut No. 46 represents Vranosco- 

 pus 7nacropi/gtis, an Australian species, which has no first 

 dorsal ; the head of Borichlhys is represented by No. 45, 

 drawn to show the branching mucoducts ; a scale of Ga- 

 dopsis is shown by No. 26 ; and one from the lateral line 

 of Hemerocaetes by No. 43. 



Family I.— URANOSCOPID^. 



Trachinidce, Bonap. Ventrals composed of a spine and five 

 jointed rays, situated before the pectorals (in Trichodon and Sillago a 

 little behind the pectorals). Scala cycloid, or wanting, acanthoptery- 



