
AILMENTS AND DISEASES 

by the head, to close the operculz and mouth, and the rest of the body 
immersed for five seconds, the treatment to be repeated at intervals of one 
day. All newly acquired fishes should be so treated before introduction 
into an established aquarium. No ill results follow and salutary effects 
are certain. 
A recent highly recommended remedy is the ANTIGYRODACTYLIN,” 
of Paul Nitsche, for the extirpation of surface parasites on fishes, especially 
those of the aquarium. The fishes should be well fed about two hours 
before treatment and receive no food three hours thereafter. ‘The treat- 
ment is to be applied three succeeding days. ‘The fish is to be taken by 
the head and gently passed backward and forward through the Antigyro- 
dactylin for 1% to 134 minutes, not longer. Then it should be 
placed in a vessel containing well-aerated water, that the parasites may 
drop off and sink to the bottom. After five minutes it should be 
transferred to a second similar vessel, and then, after expiration of another 
five minutes, to a third large shallow-water vessel containing just sufficient 
water to enable the fish to swim. This water should be changed daily and 
the vessel scoured. It is advisable to have the water of each vessel one or 
two degrees colder than the preceding, on account of its effect on the 
parasites, as it will aid in their leaving the fish. 
If the fishes show indications of exhaustion after the bath, they should 
be kept in motion for some time with a light wooden rod. 
A litre of Antigyrodactylin is sufficient for the treatment of twenty 
fishes. Taken internally it is poisonous, but is harmless externally, even 
on wounds and abrasions. 
VeceTAL Parasires aND Parasitic Diseases. All animal and vege- 
table substances are subject to the attack of low forms of vegetal parasites, 
and though they are not all necessarily malignant, many of the diseases of 
aquatic animals and plants are directly due to the presence of these micro- 
organisms, which are saprophytic upon the dead and parasitic upon the 
living tissue. 
The vegetal parasites found on animal bodies belong to the class of 
Cry ptogamia and the orders Alge and Fungi; distinguished from each other 
by the presence of chlorophyll or other coloring substances in the former 
and their absence in the latter. 
Parasitic Atc&. The aquatic forms of this order, or those which 
have preserved some essential algal features, found on animals, consist of 
single or branching, cylindrical or flattened filaments, which have no method 
of fixing themselves but are firmly held by the crossing of their fibres. The 
reproductive system consists of round or oval spores enclosed in a case or 
*To be obtained of H. Lehmann & Co., Chemists, Berlin. 
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