FISCUS 



Parts of it have been translated 

 into English : Commentary on 

 Kant's Critick of Pure Reason, J. 

 P. Mahaffy, 1866; Descartes and 

 his School, J. P. Gordy, 1887 ; A 

 Critique of Kant, W. S. Hough, 

 1888; Life and Character of Bene- 

 dikt Spinoza, Frida Schmidt, 

 1882. 



Fiscus. Latin word, meaning a 

 purse, which came to be applied 

 to the treasury of the emperor in 

 ancient Rome, as opposed to the 

 aerarium (q.v.), the treasury con- 

 trolled by the senate. As the power 

 of the latter declined, the fiscus 

 gradually became the state treas- 

 ury for the whole empire, the func- 

 tions of the aerarium being ulti- 

 mately limited to the municipal 

 finances of Rome. 



Fiset, SIR JOSEPH EUGENE (b. 

 1874). Canadian surgeon and sol- 

 dier. Born at Rimouski, March 15, 

 1874, he was the son of Hon. 

 J. B. R. Fiset, a senator. Educated 

 at Rimouski, and Laval University, 

 he completed his medical training 

 in London and Paris. Having 

 joined the Canadian militia, Fiset 

 served with the Canadian contin- 

 gent in S. Africa. In 1903 he was 

 given the D.S.O. and reached the 

 rank of colonel. From 1903-6 he 

 was director-general of medical ser- 

 vices, and in 1906 he was made 

 deputy-minister of militia and de- 

 fence. As such, he had much to do 

 with equipping the Canadian forces 

 for service in the Great War. In 

 1917 he was knighted. 



Fish. One of the phyla or sub- 

 kingdoms of the animal world. 

 Fishes may be denned as cold- 

 blooded vertebrate animals, living 

 in water, and breathing by means 

 of gills. In a few cases a primitive 

 lung is present, and the fish can 

 breathe air directly. The limbs, 

 when present, are modified into 

 paired fins ; there are also unpaired 

 fins which consist of folds or out- 

 growths of the skin. The body 

 generally tapers towards the ex- 

 tremities, and is specially adapted 

 for rapid passage through the 

 water with the minimum of re- 

 sistance. Sometimes the body is 

 greatly flattened either vertically, 

 as in the rays, or laterally, as in 

 the sole and turbot. In nearly all 

 the genera the heart has two 

 chambers and contains venous 

 blood only. With few exceptions 

 fishes reproduce their kind by 

 eggs which are deposited in the 

 water and fertilised by the male 

 after they leave the body of the 

 female, though a few species 

 bring forth living young. 



Fishes are found in all waters, 

 both marine and fresh, and at 

 almost all temperatures. Some- 

 thing like 2,300 species of fresh- 



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Fish. Diagrams illustrating the structure of fishes. Above, skeleton of common 

 perch : a. pre-maxillary bone ; b, maxillary bone ; c, under jaw ; d, palatine 

 arch; e, cranium; f, inter-operculum; g, g', vertebral column; h, pectoral fin; 

 i, ventral fin ; k, 1, dorsal fins ; m, anal fin ; n, n', caudal fin. Below, internal 

 anatomy of carp: br, branchiae or gills; c. heart; ei, intestinal canal ; o, 

 ovaries ; a, a', anus ; o', oviduct 



water fishes are known to science ; 

 about 3,500 species are littoral; 

 many others inhabit the seas far 

 from land ; and about 100 genera, 

 including numerous species, have 

 been met with hi the lowest depths 

 of the ocean. 



The skeletons of fishes are in 

 most cases bony ; but in the Elas- 

 mobranohs they are cartilaginous 

 in character. In addition to the 

 skeleton supporting the body out- 

 line and the limbs, there are often 

 numerous bony rays supporting the 

 unpaired fins also. The tail, with 

 the caudal fin, is the principal pro- 

 pelling instrument, the paired fins 

 being used as auxiliaries and for 

 steering. The unpaired fins on the 

 dorsal and ventral sides of the body 

 serve mainly as balancers. The 

 scales with which the body is more 

 or less covered are in some cases 

 horny in character and in others 

 bony. In the latter case they 

 are often nearly allied to teeth in 

 structure and contain dentine 

 or ivory. 



How Fishes Breathe 

 Fishes breathe by extracting the 

 air contained in water, which is 

 taken in by the mouth and passed 

 out through the gill-clefts on either 

 side at the hinder part of the head. 

 In its course it passes over a serief 

 of arches or plates, abundantly 

 supplied with blood-vessels, and 

 the oxygen is thus brought into 

 contact with the blood very much 

 as in the lungs of terrestrial 

 animals. Most fishes are well sup- 

 plied with teeth, which in some 



families are very numerous. They 

 may be confined to the edges of the 

 jaws, but are often found on the 

 palate and even on the gill arches 

 and in the throat. There may be 

 both cutting teeth and grinding 

 ones, the latter often taking the 

 form of plates. They usually grow 

 from the surfaces of the bones of 

 the mouth, but are sometimes 

 found in sockets. They are usually 

 replaced when worn down by fresh 

 teeth developing from behind and 

 not from beneath. 



Fishes have in most species well- 

 developed eyes, and their power of 

 vision is good. A few genera, found 

 in underground streams or in the 

 greatest depths of the ocean, are 

 without eyes. Experiment proves 

 that most species can hear well ; 

 and their sense of touch is highly 

 developed, the barbels which 

 are found around the mouth in 

 many species being used for this 

 purpose. Whether the sense of 

 taste is at all developed is uncer- 

 tain. In colour fishes vary greatly, 

 from the most sombre tones to the 

 most brilliant hues. As a rule, the 

 upper surface is darker than the 

 lower, an arrangement which helps 

 to make them inconspicuous. The 

 silvery appearance is due to the 

 presence of minute crystals hi the 

 scales, and causes the surface of the 

 fish to act like a mirror and by re- 

 flecting its surroundings render it 

 almost invisible. Protective colora- 

 tion is often present, notably in 

 the flatfish, which often so exactly 

 resemble the mud and sand that 



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