188 
THE VOYAGE OF H.M.S. CHALLENGEE. 
Spicules. — I. Megascleres. 1. Oxea, fusiform, 0'875 by 0‘028 mm. 2. Oi'thotnsene, 
rhabdome 0 6 2 5 by 0 '017 3 mm., cladi 018 mm. long. 
II. Microscleres. 3. Spheraster, 0 05 mm. in diameter, the conical actines traversed 
by an axial fibre. 4. Chiaster, witb slender, hair-like, truncate actines, confined to the 
choanosome, 0’015 mm. in diameter. 5. Orthodragma, also confined to the choano- 
some, 0158 mm. in length. 
Colour . — White externally, ochreous-yellow within. Size, 75 mm. in width by 
37'5 mm. in thickness. 
Habitat. — Galle, Ceylon. 
Aurora reticulata (Carter). 
Stelletta reticulata, Carter, Ann. and Mag. Nat. Hist.,ser. 5, vol. xi. p. 352, pi. xiv. fig. 4, 1883. 
Sponge somewhat globular, lobate ; oscules on the prominent part of the lobes ; 
surface uniformly reticulate ; cortex, 0'26 mm. thick. 
Spicules. — I. Megascleres. 1. Oxea, fusiform, 0'902 by 0 0243 mm. 2. Orthotrisene, 
rhabdome 0‘56 by 0‘027 mm., cladi 0‘069 mm. long. 
II. Microscleres. 3. Spheraster, with truncated actines, minutely spined at the ends, 
0’032 mm. in diameter. 4. Chiaster, 0‘008 mm. in diameter. 
Habitat . — Unknown. 
Subfamily 3. Sanidasterina. 
Genus 12. Ancorina, 0. Schmidt. 
Sanidasterose Stellettidse with a well-developed cortex which is not produced into 
tubular outgrowths. 
Ancorina cerebrum, 0. Schmidt. 
Ancorina cerebrum, 0. Schmidt, Spong. Adriat. Meeres, p. 51, pi. iii. fig. 28, 1862. 
Ancorina verruca, 0. Schmidt, op. cit., p. 52, pi. iii. fig. 29, 1862. 
Sponge. — Large, globose, lobate, with a folded surface like that of a human brain. 
Cortex 1'79 to 3'0 mm. thick, outer layer collenchymatous, containing oval cells with 
thin walls and spherical pigment granules, about 0‘048 mm. in diameter, excavated by 
intercortical cavities, from 0‘36 to 0’72 mm. in thickness ; inner layer fibrous, from I’l to 
2 ‘6 mm. in thickness. 
Spicules. — I. Megascleres. 1. Oxea 3'0 by 0‘0516 mm. (c), to 3‘0 by 0‘058 mm. {v). 
2. Dichotrisene, rhabdome 3’4 by 0’6 mm. (c), to 3‘25 by 0'039 [v), protocladus 0'064 mm., 
deuterocladus 0‘0774 mm. long. 3. Anatrisene, rhabdome 3’4 by 0-026 mm., cladi 
O’l mm., chord 0*15 mm. long. 
