156 PERCY SLADEN TRUST EXPEDITION 



108. Holoporella discoidea (Busk). 



Cellepora discoidea, Busk, Report Challenger Exp., x, pt. xxx, p. 197. 



This is a large species like the last but the orifice occupies a smaller poi'tion of the 

 zooecium. There is a colony incrusting in thick layers and one that from an incrusting 

 base sends up some flattened branches. The oral rostrum is sometimes low with a small 

 avicularium and sometimes tall and rounded with a large avicularium, in both cases the 

 beak is serrated. 



There are several avicularia lying flat on the front wall of the zooecium. The usual 

 large vicarious avicularia are spatulate in shape, not lanceolate. The peristome is 

 sometimes a good deal raised all round the orifice, the surface is roughened and the colour 

 is light brown. 



Saya de Malha, 150 fath. 



Cyclostomata. 



109. Crisia conferta, Busk, Brit. Mus, Cat., iii, p. 7. (PI. 8, Fig. 18.) 



These colonies are an inch in height. In an internode there are never more than 

 19 zooecia or more than three branches. There is usually only one branch, but where an 

 ooecium is pi'esent there are usually three, rather near together on the internode, one 

 below and two above the ooecium. The joints between the series of zooecia vary in colour 1 

 from black to pale horn colour. There is a good quantity of this Crisia. , 



Fai'quhar atoll, 150 fath. 



110. Idmonea atlantica, Forbes. Busk, Brit. Mus. Cat., pt. iii, p. 11. 

 Amirante, 15 — 80 fath.; Seychelles, 34 fath.; Cargados, 30 fath. 



111. Idmonea milneana, D'Orb. Busk, Report Challenger Exp., xvii, pt. i, p. 13.- 

 Providence, 55 fath. ; Amirante, 25 — 80 fath; Saya de Malha, 125 fath. 



112. Idmonea serpens (Linn.). Hincks, Brit. Mar. Pol., p. 453. 

 Saya de Malha. 



113. Idmonea radians (Lamk.). Busk, Brit. Mus. Cat., pt. iii, p. 11. 

 Seychelles, 39 fath. ; Amirante, 29 fath. 



114. Hornera 7-obusta, MacGillivray, Prod. Zool. Vict. Dec. xii, p. 72. 



The largest specimen of this form is 1 ^ by 1 inch in size, it is beautifully branched, i 

 but the branches do not anastomose, the peristome is always toothed. 

 Amirante, 35 fath. 



115. Entalophora proboscidea (M. Edwards). Waters, Exped. Antarct. Beige,' 

 1904, Bryozoa, p. 91. 



Amirante, 29 — 35 fath.; Seychelles, 39 fath. 



Thei"e are some bits of colonies that, I believe, belong to this species. 



