Preface begins: "In this Report sixty-eight species of Myzostomida are enumerated, of which fifty-two appear here for the first time. The Report includes, in addition to the specimens collected by the Challenger Expedition, all the new material which I have been able to gather together since the publication of my Monograph on the genus Myzostoma. I am indebted to the editor of the Challenger publications, as well as to those who have kindly furnished me with collections, for the permission, in the interests of science, to collect all the information into the present memoir. I am specially indebted to Mr. P. Herbert Carpenter, through whom I have received fifty new species. He, at my request, and with a readiness which cannot be too highly appreciated, looked for and sent me, with all the information necessary, the specimens of Myzostoma not only from the Challenger collection of Crinoidea, but also from the many others which he has examined during the past few years."
