Three new species of Ascoglossa (Mollusca, Opisthobranchia) from Hong Kong, and a description of the internal anatomy of Costasiella pallida Jensen, 1985. Morton, B.[Ed]. The Marine Flora and Fauna of Hong Kong and Southern China 2. Volume 1. Introduction and taxonomy., Hong Kong University Press, Hong Kong, 1990: i-xxviii, 1-448. Chapter pagination: 419-432. 426 [Zoological Record Volume 127]