Separate Phylum Research Articles

Submarine examination of the Virgin Rocks area, grand banks, newfoundland: Preliminary Note : Lilly H. D., 1965. Geol. Soc. Amer. Bull., 76 (1): 131–132.

The annelids traditionally included segmented worms, such as the polychaetes, oligochaetes, and leeches. Currently worms previously considered members of separate phyla have been transferred to the Annelida including Pogonophora/Vestimentifera, Echiura, and Sipuncula, called vent worms, spoon worms, and peanut worms, in order. These worms are not obviously segmented, but show traces of segmentation either at one stage of development or in limited body parts. Evidence for reassignments has come mainly through studies of genetic sequences. A consequence is that the Polychaeta is paraphyletic and thus no longer a valid taxon.

Affinities and Interrelationships of the Characeae

Abstract Developmental features of the Characeae are reviewed with reference to speculation on affinities and interrelationships of this group. A phylogenetic scheme is offered in which the Nitelloideae are considered a line distinct from the Charoideae. Nitella, on the basis of the presence of sympodial branching in its laterals and the greater degree of sterilization of its oogonium, is considered more advanced than Chara. Within Chara, ecorticate forms are considered to be derived from corticate forms. It is probable that there is some affinity between the Chaetophorales and the Charophyta, but the distinctive features of charophytes warrant their retention in a separate phylum. In an extension of Goebel's interpretation of the antheridium, the antheridial mother cell is compared to a nodal initial.