On the rare Abyssal Octopod Melanoteuthis beebei (sp. n.): a Contribution to the Phytogeny of the Octopoda.
- 1The abyssal Octopod Xelanoteubhis beebei from the Eastern Pacific is a new species differing in several important featnres from 111. lzcceias (N. Atlantic), the only other speeies of the genus.
- 2It possesses certain characters not found in the Octopoda but characteristic of the Decapodn; and i t also displays certain features which ally it with the Cirrate and Iiicirrate Octopods.
- 3Melwnoteuthis (and probably the other members of the Vampyromorphze) is the most primitive Octopod. Though referable to the Octopoda, it exhibik very clearly-marker1 affinity with the Decapoda and can be associated with neither the Cirromorphn nor the, Incirrate Octopods.
- 4It is propxed to subdivide the Octopodn. into three suborders -the Vampyrornorphn, Cirromorpha, and Tnciri. ata, whicli seem to represent three markedly divergent evolutionary tendencies.
- 5The structure of Melanotetcthis renders it highly probable that the Octopoda diverged from the Decqoda after the latter had acquired pedunculate suckers and a funnel-valve, but before t h e central nervous system underwent condensation and (See footnote, p. 469.)