Haeckel
Radial tubes cylindrical, straight, of nearly equal breadth throughout their entire length, somewhat inflated in the proximal basal end, smooth throughout the greater part of their length, but in the distal part dentate, with numerous (10 to 40) small pointed teeth, which are curved outwards, and shorter than the thickness of the tube. A. scolymantha is the commonest aulacanthid, and perhaps the commonest phaeodarian, species. Length of tubes: 0.5-1.0 mm.