1. In the Austrian sector of the Danube, 5 parasite species are registered: infusoria Trichodina sp., parasitic crustaceans Ergasilus sieboldi, trematodes Diplostomum sp. and N. skrjabini, and also acanthocephalans Acanthocephalus lucii.

2. The central and intertropicalparts of the Atlantic swarm with Pteropoda, Crustacea, and Radiata,and with their devourers the flying-fish, and again with theirdevourers the bonitos and Albicores; I presume that the numerouslower pelagic animals feed on the Infusoria, which are now known,from the researches of Ehrenberg, to abound in the open

3. The central and intertropicalparts of the Atlantic swarm with Pteropoda, Crustacea, and Radiata,and with their devourers the flying-fish, and again with theirdevourers the bonitos and Albicores; I presume that the numerouslower pelagic animals feed on the Infusoria, which are now known,from the researches of Ehrenberg, to abound in the open

4. The central and intertropical parts of the Atlantic swarm with Pteropoda, Crustacea, and Radiata, and with their devourers the flying- fish, and again with their devourers the bonitos and Albicores; I presume that the numerous lower pelagic animals feed on the Infusoria, which are now known, from the researches of Ehrenberg, to abound in the

5. The central and intertropicalparts of the Atlantic swarm with Pteropoda, Crustacea, and Radiata,and with their devourers the flying-fish, and again with theirdevourers the bonitos and Albicores; I presume that the numerouslower pelagic animals feed on the Infusoria, which are now known,from the researches of Ehrenberg, to abound in the open