The geographical distribution of animals, with a study of the relations ...

;408 ZOOLOGICAL GEOGRAPHY. [part hi.out the important facts of distribution. All that can be donehere is to note the characteristic and peculiar genera, and anyothers presenting features of special interest.In the great family of the snails (Helicidse), the only generastrictly confined to the region are, Partula, now containing above100 species, and ranging over the Pacific from the Solomon Isleson the west, to the Sandwich Islands and Tahiti on the eastand Achatinella, now containing nearly 300 species, and whollyconfined to the Sandwich Islands. Pfeiffcria is confined to thePhilippine Islands and Moluccas ;Cochlostyla to the Indo-MalayIslands and Australia ;Bulimus occurs in most of the insulargroups, including New Zealand, but is absent from Australia.Among the Aciculidse, the widely-scattered Truncatella is theonly genus represented.Among DiplommatinidaB, Diplommatinais the characteristic genus, ranging over the whole region,and found elsewhere as far as India, with one species inTrinidad. The extensive family Cyclostomidse, is not wellrepresented. Seven genera reach the Austro-Malay Islands,one of which, Eegistoma, is confined to the Philippines, Moluccas,New Caledonia, and the Marshall Islands. Omphalotropisis the most characteristic genus, ranging over the whole regionGallia is confined to the Philippines, Ceram, and Australia;Bealia to New Zealand and the Marquesas. The genus Helicinaalone represents the Helicinidse, and is found in the whole regionexcept New Zealand. The number of species known fromAustralia is perhaps about 300; while the Polynesian sub-region,according to Mr. Harper Pease, contains over 600 ;the Austro-Malay Islands will furnish probably 200; and New Zealandabout 100 ; making a total of about 1,200 species for the wholeregion.AUSTEALIAN SUR-EEGIONS.Few of the great zoological regions comprise four divisions sostrongly contrasted as these, or which present so many interestingproblems. We have first the Austro-Malay Islands, an equatorialforest-region teeming with varied and beautiful forms of lifenext we have Australia itself, an island-continent with its satellite