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the blind Urodele of the caves of Carniola, the blind Fish 

 (Amblyopsis spebceus) of the Mammoth caves of Kentucky, numerous 

 Insects, &c. These, like abyssal species, are blind, and usually 

 colourless, and are obviously specialised derivatives of the ordinary 

 fresh-water or land fauna. 



In the Terrestrial Fauna, also, we find certain groups pre- 

 ponderant, others absent or nearly so. A terrestrial Amoeba has 

 been described, and the Mycetozoa are all terrestrial, but no other 

 Protozoa, nor any Sponges, Coelentrates, or Echinoderms. Among 

 Platyhelminthes we have the numerous species of Land-Planarians 

 and the Land-Nemertines, and among Chsetopods nearly the 

 whole of the Earthworms. Several Crustacea are more or less 

 completely adapted to terrestrial life, such as the Woodlice, Land- 

 crabs, Cocoa-nut Crab, and Burrowing Crayfish. The Onychophora 

 and Myriapoda are characteristic land-animals, so also are most 

 Arachnida and many Insects. Among the Mollusca the only 

 terrestrial forms are the majority of pulmonate Gastropoda. Among 

 Fishes the Climbing Perch, Periophthalmus, and some others are 

 imperfectly adapted to life on land, and the Caducibranch Urodeles, 

 the Anura, and the Gymnophiona are all terrestrial or semi- 

 terrestrial. The Lacertilia, Sphenodon, the majority of Snakes, 

 and the Tortoises are land-animals, and so also are many Birds, 

 including all the Ratitse, the Crypturi, Gallinse, &c., and the vast 

 majority of Mammals. 



Among terrestrial animals, those which habitually live on the 

 open ground must be distinguished from arboreal forms, such 

 as Tree-Kangaroos, Sloths, and Monkeys, which pass their lives 

 among the branches of trees, and from cryptozoic forms, which 

 live under stones, logs of wood, &c., such as Land-Planarians, 

 Peripatus, Centipedes, and Woodlice. 



Lastly, we have the Aerial Fauna, including animals capable 

 of sustaining themselves for an indefinite period in the air, such 

 as most Insects, the large majority of Birds, and Bats. The 

 Flying Fishes, Flying Dragons (Draco), Flying Phalangers, Flying 

 Squirrels, and Flying Lemur (Galeopithecus) are semi-aerial. 



The majority of land-animals live at or near the sea-level, and 

 as we ascend mountains the fauna undergoes a gradual impoverish- 

 ment as the snow-line is approached. The higher ranges of all great 

 mountains have a characteristic Alpine Fauna. In the European 

 Alps, the Chamois (Rupicapra), Alpine Hare (Lepus variabilis), 

 and Marmot (Arctomys marmot] may be specially mentioned ; in 

 the Himalayas, Yaks (Poephagus), Musk-deer (Moschus), Goats 

 and Ibexes (Capra), besides abundant Birds and Insects ; in the 

 Andes, the Condor (SarcorJiamphus) ; in the New Zealand Alps, 

 the rapacious Kea or Mountain Parrot (Nexfor 



