Marine Animal Forms in Fresh Water. 55 



taro anil IMolinclla, as was iiiclicati'd by Pollini (Viaggio al Lago 

 di (jai'da.i). ,22) . U'itli regard to PL liinunda and PL Su/ea, consult 

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

 si)ocics also occur in the torrid zone ; but according to Hamilton- 

 Buchanan, some species are abundant in the brackish water of 

 the Ganges, up which they ])ass as far as the tide reaches. 



G. Belone cuncila, Ham.-13uch., and caudimacula, Val., in the 

 East Indies. According to Professor Peters, Hemiramphus far, 

 liiipp., ascends the rivers in Mozambique. 



6 A. Galeichthys marinus, Mitchill {Parra,Nix\.), of Cuba and 

 New York, G. j'eliceps of the Cape, and Plotosus lineatus, Val., 

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



7. Tetrodon fuhaca, Eorsk., 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 ])]easure ; his frigid zone cor- 

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

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

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



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



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

 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 {Artemiu) arc 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, Ilartm. and Lithoglyphus, 

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

 their sei)aration from the Littorinida is scarcely admissible, and 

 that it was only tried ou: account of the difference of habitation. 

 Such R wide separation of the smooth Rissnce {Paludinella, Loven, 

 Beck) iroui Hydrobia, Hartm. {Amnicola, llaldeman, Paludinella, 

 J. C. Schmidt) especially cannot be allowed. 



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

 The yEtherice are referred by him to the Najudea. 



15. Xovacidina gangeiica, Bens., perhaps only in brackish 

 water, like Potamouiya (Corbulacea) and (5/?a/Aof/o/i (Mactracea). 



The following considerations arise out of this Table : — 



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



