1, 2, 3 & 4— Varieties of Haliomma. Haliomma Humboldtii (?) of Ehrenberg, from Cambridge, Barbados, numerous and variable. Although there are sometimes indications of spines radiating from the centre, as in Stylodictya, yet the points round the edge appear to be merely "marginal appendages."—Diameters, including spines, from .0077 to .0085. 5 & 6— Muller describes these as stages of growth of the
Haliomma, where the outer web is spinning itself over and round the central nucleus, and the siliceous rafters or supports extending like a framework from the nucleus to the exterior covering. Page 21 ';' " Thalassicollen Polycystinen, &c., des Mittelmeeres."
7 & 8— Spines or Spicules in Barbados deposit.
