Cyamon Gray 1867

Figure 4.Cyamon amphipolyactinum sp. n., holotype ZMA Por. 22412, A shape (arrow) encrusting a fragment of sandstone (scale 1 cm) B long thin style B1 details of apices of long thin style C short thin style C1 details of apices of short thin style D short thick styles showing size variation D1 detail of head of short thick style E polyactines (three-, four-, five-, and seven-claded) and one amphipolyactine showing size differences E1 detail of bulbous end of lateral cladus F amphipolyactines full-grown and spined (left) next to incipient smooth spicule (right).

Figure 5.Map showing locality off the Mauritanian coast, where Cyamon amphipolyactinum sp. n. and Cyamon arguinense sp. n. were collected during the Netherlands Mauritania II Expedition, June 1988.

Figure 5.Map showing locality off the Mauritanian coast, where Cyamon amphipolyactinum sp. n. and Cyamon arguinense sp. n. were collected during the Netherlands Mauritania II Expedition, June 1988.

Figure 6.Cyamon arguinense sp. n., holotype ZMA Por. 06723, A shape (arrow) encrusting a fragment of sandstone (scale 1 cm) B subtylostyle B1 details of apices of subtylostyle C short thin centrotylote style C1 details of apices and middle part of short thin centrotylote style D polyactines.

Figure 15.Cyamon hamatum sp. n. (Cyamon vickersii sensu Burton and Rao 1932), from S India, A slide BMNH 1931.1.1.19a, labeled ‘Cyamon vickersii (Bow.) Ind. Mus. Coll.’ in Burton’s handwriting B microphoto of section of skeleton made from the slide C characteristic polyactine with recurved hook-like spines on basal cladus and short stubby lateral cladi.