“Ss 

AILMENTS AND DISEASES 

Conciusion. There can be no question that the finely bred Gold- 
fishes are more liable to illnesses than the ordinary breed. They are all 
constitutionally weak and naturally subject to disturbances of digestion, 
ailments of the swimming bladder, dropsical tendencies, and physical ex- 
haustion; the latter due to atrophy of the muscles from disuse and from 
having gone largely into the formation of the abnormally long and dupli- 
cated fins, the very effort to wield which is exhausting and compels the 
fishes to swim as much by movements of the body as of the long unwieldy 
fins and tails. When affected by diseases these fishes are devoid of much 
repellant, recuperative or sustaining power, as they are coddled, weakly, 
unnatural monstrosities in whom life is kept by the constant attention of 
the fancier. It will be noticed that it is the most highly prized fishes 
which are most prone to illness and which soonest succumb, so that the 
losses to the breeder are principally these and not the “sports’’ or partial 
reverts. But on account of their value and the constant demand, the toy 
varieties receive the principal attention of the skilled breeders, to which 
must be added the fascinating uncertainty as to the result of a season’s 
labor,.as any fish that hatches may possibly develop into a fine specimen, 
if it survives. 
Although the foregoing investigations of fish diseases were conducted 
by the author and his expert friends with aquarium fishes, the diseases and 
remedies also apply to food fishes, and the methods of treatment suggested 
can be used for them as well, if modified to suit existing conditions. The 
tenacity of life of the common goldfish is such that it is generally employed 
for ichthiological research pertaining to diseases and their treatment. 
PARASITES AND PARASITIC DISEASES 
The diseases of fishes are both parasitic and non-parasitic. Of the 
former, the parasites may be either animal or vegetal; which, according to 
the parts infested, are classed as Ecto- or surface and Ento- or internal 
parasites. It is proposed to briefly describe the common forms and 
the more or less effectual treatment for their eradication. 
AnIMAL Parasites AND Parasitic Diseases. Nearly all classes of 
animals include among their inferior ranks members which are either para- 
sites or messmates at some period of their existence. True parasites are 
those which live at the expense of their hosts, either establishing them- 
selves in their organs and tissues or leaving them after a meal, like the 
leech and the larve of predatory insects; while others require this assist- 
ance at determinate periods, either in early youth, like the young of some 
mussels, or during the infirmities of old age, though many are internal or 
external lodgers all their lives. _Messmates are those which share in the 
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