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 A HISTORY OF NORFOLK thin, calcareous border. Zooecia tubular, in radiating lines, crowded, without any radiating intervals. Yarmouth, on Sabellaria tubes (Harmer). ENTOPROCTA 25. Pedkellina cernua (Pallas). Colonies consisting of clusters of whitish cup-shaped zooids, laterally compressed, sur- mounted by a crown of tentacles, and attached by stout, tapering, spiny stalks to a creeping stolon. The zooids, when disturbed, sway themselves about with much vigour. Yar- mouth, on Vesicularia (Harmer). 26. Loxosoma phascolosomatum, Vogt. Resembling the preceding, but the zooids are in groups of separate individuals, not con- nected by a stolon. Tentacular crown placed obliquely ; stalk long, smooth, flexible. On tail end of Phascolosoma (P.). VIII. ECHINODERMA {Star-fishes, Sea-urchins, etc) Nomenclature : Bell, British Museum Catalogue, 1892. 1. Asterias rubens, Linn. The common red cross-fish or * five-fingers.' Cromer (Geldart). 2. Solaster papposus (Fabr.), The red 'sun-star'; arms 12 to 15. Cromer (P. ; Geldart). 3. Ophiura albida, Forbes. The smaller 'sand-star.' Disc and arms smooth, scaly. Inter-radial plates (on the lower surface) shield-shaped, almost as broad as long. Common under stones at Runton (Geldart). 4. Ophiopholis aculeata (Linn.). Upper surface of disc ornamented with small, irregular plates, separated by tracts of minute blunt spines or granules. Upper plates of the arms ovate, surrounded by small acces- sory plates. Off Cromer, fairly common (P.). 5. Ophiothrix fragilis (O. F. Muller). The common ' brittle-star.' Disc covered with spines in the intervals between the long triangular radial shields. Arms very flexible with long spines. Yarmouth (Harmer). 6. Echinus miliaris, Linn. The shallow-water urchin. Shell more or less depressed above and distinctly pentangular. Rimton (Geldart), Yarmouth (Harmer). 7. Echinus esculentus, Linn. The edible urchin. Shell almost spherical. Off-shore only, except after gales when it may be cast ashore (Geldart). IX. TUNICATA {Sea-Squirts or Ascidians) 1. Ascidiella virginea (O. F. MUller). Body irregularly quadrangular, compressed, the two siphons forming the upper angles. Test smooth, transparent, colourless, showing the brilliant crimson and white colouration of the skin beneath. Length about 2 inches. Adherent by the base to stones or shells. Off Yarmouth (P.). 2. Ascidiella aspersa (O. F. MUller). Body ovate, compressed, nearly twice as long as broad ; apertures near together, ter- minal. Test semi-transparent, rough with conical papillae, especially near the siphons. Length, 2-3 inches. Adherent by the base and part of the left side to stones, shells, and Fucus, in shallow water. Off Cromer (P.). 3. Cynthia {Microcosmus) claudicans, Sav. Body erect, irregularly conical or ellipsoidal, the mouth terminal, the cloacal pore about the middle of the dorsal side ; both apertures 4- lipped, on pyramidal siphons. Test leathery, opaque, brownish, wrinkled, beset with fine prominences which agglutinate sand particles. Branchial folds 8 or 9 on each side. Off Cromer (P.). 4. Cynthia {Polycarpa) comata. Alder. Body globular, lying free in sand, to which it binds itself by numerous long branched adhesive threads. Apertures 4-lipped, on quadrangular siphons, lying close together in a groove which closes over them during re- traction. Branchial folds 4 on each side. Off Cromer (P.). In external appearance and habits this species resembles Molgula {Eugyra) glutinans, Moll., which is recorded from the Silver Pit, and is distinguishable by the 6-lipped mouth and the absence of branchial folds. 5. Molgula ampulloides^ ■3S. Beneden. Body barrel-shaped, i inch long ; apertures terminal on short siphons, the mouth 6-lipped, the cloaca 4-lipped. Inhabits fine sand, to which the animal binds itself by fine adhesive threads. Branchial folds, 6 pairs. Off Cromer (P.). 86