Marine Animal Forms in Fresh Water. 68 



taro and Molinella, as was indicated by Pollini (Viaggio al Lago 

 di Garda^ p. 22) . With regard to PL limanda and PL Solea, consult 

 Schmarda {op. cit. p. 148). I do not know whether ascending 

 species also occur in the torrid zone ; but according to Hamilton- 

 Buchanan, some species are abundant in the brackish water of 

 the Gangesj up which they pass as far as the tide reaches. 



6. Belone cancila, Ham.-Buch., and caudimacula, Val., in the 

 East Indies. According to Professor Peters, Hemiramphus far, 

 Riipp., ascends the rivers in Mozambique. 



6 b. Galeichthys marinus, Mitchill {Parra, Val.), of Cuba and 

 New York, G. feliceps of the Cape, and Plotosus lineatus, Val., 

 found from the Red Sea to the Friendly Islands, are sea fishes. 



7. Tetrodon fahaca, Forsk., in the Nile ; other species in the 

 Ganges. 



8. Syngnathus deocata, Ham.-Buch., in the Kawarlayi river in 

 Northern Bengal ; >S^. Zambesensis and Argulus, Peters, in Mo- 

 zambique. 



9. Of the distribution of the marine Crustacea Dana has given 

 a most copious summary at the conclusion of his great work, of 

 which I have availed myself with pleasure ; his frigid zone cor- 

 responds with my No. I., subfrigid with II., cold temperate and 

 subtemperate. III., temperate (the Mediterranean Sea) and 

 warm temperate, IV., subtorrid and torrid, V. 



10. Chcetilia ovata, Dana, from Chili, is a freshwater species. 



11. Jaera, Leach, a marine genus of the subdivision Asellidde, 

 the species of which occur from Greenland to the warm tempe- 

 rate zone. The occurrence of the Asellus in Greenland is 

 doubtful ; Fabricius himself did not see it. Nothing belonging 

 to this subdivision is known from the tropics. 



12. The Brine Shrimps {Artemia) are certainly not freshwater 

 animals, nor do they live in the sea. The other members of 

 this division are freshwater animals (for example Branchipus). 



13. In this case I follow Woodward^s division, according to 

 which the spiral operculum constitutes the distinction between 

 the two families — (by this, Hydrobia, Hartra. and Lithoglyphus, 

 Mhlfld. must be referred to the Melaniacea) — but I think that 

 their separation from the Littorinida is scarcely admissible, and 

 that it was only tried on account of the difference of habitation. 

 Such a wide separation of the smooth Rissoa [Paludinella, Loven, 

 Beck) from Hydrobia, Hartm. [Amnicola, Haldeman, Paludinellttj 

 J. C. Schmidt) especially cannot be allowed. 



14. Here, according to Woodward, the African Galathea. 

 The JEtheri(2 are referred by him to the Najadea. 



15. Novaculina gangetica, Bens., perhaps only in brackish 

 water, like Potarnomya (Corbulacea) and Gw«^Ao6?o?^ (Mactracea). 



The following considerations arise out of this Table : — 



A. If we add for each zone the marine families occurring 



