< 1897.) The Origin of the Galapagos Islands, 867 
Ortmann makes the following remarks: “The distribution 
nof the Trapeziide is very simple but characteristic, and agrees 
-very well with the limitations of the modern geographical 
regions of animals... Wherever in the whole Indo-Pacific area 
coral reefs are found, there are also Trapeziidæ.- Most of the 
species and subspecies extend over the whole Indo-Pacific 
region, from the Red Sea and East Africa to the Loo Choo 
-and Sandwich Islands, to Queensland in Australia and to the 
- Paumotu Islands [and even the west coast of Central America]. 
Some forms, according to the present data, seem to be a little 
- more limited, for instance, Trapezia ferruginea dentata has not 
yet been recorded from the Indian, but is found from the Sulu 
‘Sea eastwards; Trapezia ferruginea areolata is known eastward 
from Ceylon; Trapezia digitalis bella only from the Paumatu 
- Archipelago. It is quite possible, however, that these forms 
will be discovered later in those places where they at present 
have not yet been found. Some species (Trapezia digitata 
speciosa and Quadrella coronata) have been found only in few 
-isolated places, but these places are so far distant from each 
- other, that we can assume with certainty their general distri- 
bution, even if they might be rare forms. 
At the west coast of America it is not possible to distinguish 
-any well characterized. peculiar species; the four species men- 
tioned from this region are also found.in the Indo-Pacific 
“region. Therefore, we must conclude, that the west American 
Region received these species from the Indo-Pacific. How 
these forms were able to pass the barrier of the open Pacific 
Ocean, can only be. guessed. Migration along. the North 
- Pacific. shore line is impossible, the Trapeziide being exclu- 
5 sively tropical forms; the conditions of former geological times 
can not be considered, since this family, as will be’seen im- 
: mediately, is of very recent age. Only onesupposition remains, 
` that the. Trapeziide possess means of migration in free swim- 
Ming planctonic larvae, which enable them to reach inside the 
tropics, the western coast of America from the Pacific Islands. 
| This, however, remains a simple supposition ;. we know noth- 
-ing whatever about the propagation and ee: of the 
Trapeziide and about their eventual larve. 
