Geographische Verbreitung, Reisen. 193 



part of the American Continent, and about the same distance from Samoa on 

 the South. The group extends from North- West to South-East about 350 miles. 

 To the North-West of it is a long chain of small low islands and reefs, extend- 

 ing over several hundred miles, and some at least of which (e. g. Laysan) have 

 zoological affinities with the Hawaiian Islands proper. These latter are exceed- 

 ingly mountainous, rising to elevations of nearly 14000 feet in Hawaii, 10000 

 feet in Maui, and to lesser elevations in the other islands. The first section of 

 Perkins' essay briefly describes their remarkable physical features, and their 

 topography is also illustrated by photographs of relief-maps, which show the 

 enormous amount of erosion that has occurred. The second section deals with 

 "general aspects of the flora and fauna". The littoral flora is *poor, but 

 the littoral fauna is less so, and does contain some endemic forms, though many 

 of its species are not strictly littoral, but also ränge inland. Above the coast, on 

 the leeward side especially, is a zone of arid lower slopes, much of which has been 

 greatly altered by human agency, but which still has a certain number of endemic 

 plants and animals, though the latter are probably but a remnant of a once large 

 and important section of the fauna. Above this dry area the belt of continuous 

 forest is reached at elevations varying from about 1200 — 3000 feet. This is 

 Tiow by far the most interesting part of the islands, being composed to a very 

 large extent of endemic plants (^about 757o of ^^^e species are endemic), and 

 being the habitat of the vast majori ty of the known endemic animals. Some 

 types of this forest are illustrated in several beautiful plates. It varies greatly 

 in its composition in different islands. The numerical proportions of the plants 

 composing it vary much, and it also differs greatly on the windward and leew- 

 ard sides and in different localities of the same island. In its natural state it is 

 extremely dense, but over large areas it has been greatly altered or even totally 

 destroyed, chiefly by the ravages of imported cattle. Cattle have been known 

 to reduce the densest forest to open timbered land covered with foreign grasses 

 vvithin 15 years. Above the forest on the highest mountains are open and drier 

 regions, which of tenhave a peculiar fauna of endemic insects ; but it is note- 

 worthy that certain xerophilous insects found on the arid lower slopes, below the 

 forest and rain-belt, may also reappear in these dry regions above the forest. 

 Perkins speaks of the close attachment of many insects to particular plants, 

 noticing, for instance, the fact that the small crickets of the genus Paratrigoni- 

 dium affect each their own species of fern. Also in writing of the rain-soaked 

 woods on the windward sides of the islands, he remarks on the wonderfully 

 perfect condition in which extremely delicate moths are found during the fre- 

 quent torrential downpours, and on the activity of some larger Lepidoptera even 

 during the heaviest showers. In the section devoted to the summary of his 

 wanderings and methods of collecting, something may be gieaned of Per- 

 kins' hardships in these rain-sodden forests, into which he bore alone his tent 

 and provisions and in which he camped alone for periods as long as food and 

 equipment lasted. 



One of the most striking features of the endemic fauna is the inconspi- 

 cuousness of the forms which compose it. With the exception of a few 

 brilliantly coloured birds and of one handsome butterfly (Fi/rameis tammeamea), 

 the species are almost all very inconspicuous. Very many of them are very small 

 and obscure forms of hidden life and extremely special habits. These facts led 

 earlier investigators to exaggerate very greatly the rarity of species and of in- 

 dividuals. Perkins does not think the number of really rare species is greater 

 ihan elsewhere over an equal area of land, while the abundance of individuals of 



Zentralblatt f. Zoologie, allgem. u. experim. Biologie. Bd. 4. 13 



