A HISTORY OF SUSSEX 



43. Isodictya mammeata, Bowerbank.* 

 Hastings. 



44. Isodictya simu/ans, 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. Isodictya dichotoma, Bowerbank.* 

 Hastings. 



46. Isodictya fucorum, Bowerbank.* 

 Hastings. 



47. Isodictya rugosa, Bowerbank.* 

 Hastings. 



48. Isodictya 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 eegagropila, Bowerbank.* 

 Hastings. 



51. Desmacidon coptosa, Bowerbank.* 

 Hastings. 



52. Desmacidon rotalis, Bowerbank.* 

 Hastings. 



53. Rapbyrus grtffithsii, 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 occu/ata, 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 grad/enta, 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. 



CCELENTERA 

 HYDROZOA 

 HYDROIDA 



ATHECATA 

 CLAVID.*: 



1. Clava multicornisj 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^E 



2. Hydractinia ecbinata, 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 

 ccenosarcal 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. 



7 6 



3- Coryne van-benedenii, Hincks. 



Polypite small, club-shaped, with knob- 



