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 MARINE ZOOLOGY gi. Diastopora sarniensis, Norman. Forming encrusting patches upon shells and rocks. The zooecia radiate from a centre, the anterior ends curving upwards and being free. The apertures are elliptical and alternate, and in many cases closed, except as regards a small tubular orifice which projects from the operculum. There is a plain white basal border surrounding the colony. Common from deep water. Hastings. 92. Diastopora sub-orbicularis. Colonies forming circular crusts upon dead shells. The zooecia radiate from a centre, the apertures being elliptical, alter- nate, and only occasionally raised. Zooecia and opercula minutely perforated. From deep water ; not very common. Hastings. LiCHENOPORIDiE 93. Lichenopora hispida, Fleming. This species forms little mounds consist- ing of tubular zooecia arranged radially, the free ends projecting beyond the common matrix ; the apertures are thrown into several sharp points. Colonies also occur in compound form of greater extent, the surface appearing dimpled. There is a wide border of the basal layer displayed around the colonies. Very common upon shells from deep water. Hastings. CTENOSrOMATA Al,CYONIDIIDiT 94. Alcyonidiutn ge/atinosum, Linnaeus. Colonies consisting of zooids embedded in irregularly lobed masses of a gelatinous matrix. Specimens from deep water are often very large and intricately lobed. Colonies are smooth and of a light buff or brown-green colour. Common. Hastings. 95. Alcyonidium hirsutum, Fleming. In occasional years this species is found covering weed at low tide in profuse masses. The surface of colonies is mammilated and the colour a bufF-brown. Hastings. 96. Alcyonidium parasiticum, Fleming. Forming inconsiderable colonies upon coralline stems ; colour, grey-brown. When the zooids are withdrawn the surface is thrown somewhat into wrinkles. From the coralline zone ; not common. Hast- ings. 97. Alcyonidium mytili, Dalyell.* Flustrellid^ 98. Flustrella hispida, Fabriciu Somewhat Hasting Hastings. VESICULARIIDi* 99. Vesicularia spinosa, Linnaeus. This species forms erect, horny, branch- ing growths of fine texture, and when dry resembles in colour and appearance so many strands of tow. The main stems are bent in zig-zag manner, giving off branches at each bend, but they are concealed by a number of finer, climbing tubes which also branch. The zooecia are ovately cylindri- cal and are arranged uniserially and equi- distantly upon the branches. Not uncommon from moderate to deep water. Hastings. 100. Amathea londigera, Linnaeus. Forms little intricate masses, consisting of horny, branching stems bearing at regular intervals linear groups of about eight zooecia, resembling in imagination so many little sacks stacked together. The stems repeatedly divide, the division taking place immediately after each group of zooecia Upon weed, etc., from moderately deep water. Not uncommon. Hastings. 10 1. Bowerbankia imbricata, Adams.t Brighton. 102. Bowerbankia pustulosa, Ellis and So- lander. Little shrub-like growths of about i^ inches in height. Zoarium horny, brown in the lower parts, and branching at an angle of about 30°. The zooecia are ovately cylindrical and occur in biserial and slightly spiral order at the end of each branch, or immediately before re-branching takes place. Upon trawled rock ; rare. Hastings. 103. Farrella repens, Farre.* Hastings. Farrella repens var. elongata.* Hastings. BuSKIIDit 104. Buskia nitens. Alder.* Hastings. Cylindrceciidje 105. Anguine Ha palmata^ Van Beneden. Occurring in pendent, mud-coloured clusters upon rocks at low tide. Length from 3 to 4 inches. The stems, with their short and palmate branches, are rather cat- kin-like. The zooecia are long and tubular, 93