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 A HISTORY OF SUSSEX 43. hodictya mammeata, Bowerbank.* Hastings. 44. hodictya simulans, Johnston. Sponge rather low and straggling, branch- ing, the branches cylindrical or slightly com- pressed and anastomosing. Oscula distinct and upon one side only of the branches. Texture, fine ; colour, ash-grey to brown. From moderately shallow water; somewhat rare. Hastings. 45. hodictya dichotoma, Bowerbank.* Hastings. 46. hodictya fucorum, Bowerbank.* Hastings. 47. hodictya rugoia, Bowerbank.* Hastings. 48. hodictya obscura, Bowerbank.* Hastings. 49. Desmacidon fruticosa, Bowerbank. Sponge extensive, low, spreading, coarse in texture, grey, and giving off short wide fun- nel-like branches with wide terminal orifice, which also extends partly down the side. Growing rather insecurely upon two or three stones. From the Diamond Ground ; some- what rare. Hastings. 50. Desmacidon agagropila^ Bowerbank.* Hastings. 51. Desmacidon coptosa, Bowerbank.* Hastings. 52. Desmacidon rotalis, Bowerbank.* Hastings. 53. Raphyrus griffithsii, Bowerbank. Sponge bark brown, forming rounded masses upon stones, etc., the whole surface being closely pitted. From moderately deep water; somewhat rare. Hastings. 54. Chalina occulata, Bowerbank. Sponge with a pedicel. Branches close and compact, and given off somewhat in the same plane. In a general way the oscula are ar- ranged upon two opposite sides of the branches, but this order is by no means constant. A fine specimen measures 12 inches high. From the Diamond Ground ; common. Hastings. 55. Chalina montaguii, Bowerbank.* Hastings. 56. Chalina gracilenta, Bowerbank.* Hastings. 57. Dysidea fragilis, Bowerbank. Sponge forming somewhat shapeless or lobed masses, growing upon rock, etc. The fibres are cored with sand grains, and the sponge when dried is extremely fragile. Spicules are practically absent in this genus. Trawled in moderately shallow water ; not uncommon. Hastings. 58. Dysidea coriacea, Bowerbank.* Hastings. CGELENTERA HYDROZOA HTDROIDA Athecata ChAvinm 1. Clava multicornis, Forskal. Polypite naked, spindle-shaped, semi- opaque white ; tentacles many and long, distributed irregularly over the body ; gono- phores round and borne below the tentacles. Upon shells and under stones at low water. Colonies small ; somewhat rare. Hastings. Hydractiniid^ 2. Hydractinia echinata, Fleming. Colonies incrusting various shells occupied by the hermit crab, more particularly those of the whelk, natica and nassa ; also noted upon claw of lobster. This zoophyte is peculiar for the special- ization of its members and the form of its polypary. The alimentary polypite is naked, columnar, tapering downwards, and with a single circlet of tentacles. The pink gonophores are borne on modified polypites, giving to the colony when very prolific a delicate rose colour. There are two other kinds of Zooids, one forming coils and ostensibly a modified polypite and the other long and very contractile with bilobed * head.' The functions of these two members are problematical. Sections of the crust show superimposed reticulating galleries formed of chitine and traversed by coenosarcal threads. Comparison may be made with advantage with sections of the polyparies of Coppinia arcta, Antennularia ramosa and other species. Very common upon the shore in warm weather ; upon the approach however of cold weather the crab retires to deeper water. Hastings. Corynidj^ 3. Coryne van-benedenii, Hincks. Polypite small, club-shaped, with knob- 76