The Australian species of Tosia (Asteroidea)
Abstract
The opinion held by Fisher (1911) that the Australian forms are best kept together in the genus Tosia and the American and European forms relegated to allied genera such as Ceramaster and Plinthaster, appears to be not only the most reasonable solution to the problem, but also the most natural course out of a maze of difficulties. The proposition, however, solves for the present only part of the task for the systematist and, indeed, must be regarded as only an initial step in the reorganization of sea-stars of the Australian seas. A problem yet to be faced is the relationship of Tosia with Pentagonaster, which is not yet clearly understood, but it is felt that, when the question is fully investigated by one with sufficient data, the merging of both genera will be the only alternative.