Page:Transactions of the Linnean Society of London, Volume 8 (1807).djvu/270

250 parts of their structure. The coverings of the Sabella seem to be more of an adventitious nature, and may be considered rather as serving the purposes of habitations, than as being organized integrals of the contained animal. — If these ideas be correct, the genus Sabella does not come within our pro- vince.

III. Some