REPORT ON THE TETRACTINELLIDA. 
253 
Remarks. — Measurements of the spicules and cortex were made from type-slides in 
the British Museum. 
Geodia 7'eticulata, Bowerbank. 
Geodia reiiculata, Bowerbank, Proc. Zool. Soc. Bond., p. 300, pi. xlvi. figs. 14-20, 1874. 
Sponge. — Massive, sessile ; surface smooth. 
Spicules. — I. Megascleres. 1. Oxea, 1‘75 by 0 ‘01 9 mm. 2. Orthotrisene, 2 by 
0'0312 mm., cladi 0’2375 mm. long; chord 0’45 mm. 3. Protrisene, cladi 0’25 mm. 
long; chord 0‘12 mm., sagitta 0'206 mm. 4. Anatrisene, cladi 0’144 mm. long; chord 
0‘15 mm., sagitta 0'125 mm. 
II. Microscleres. 5. Sterraster, spherical, small. 6. Oxyaster, centrum absent, 
actines conical, 0'0254 mm. in diameter. 7. Pycnaster, actines bacillary, truncate, 
0’0085 mm. in diameter. 
Colour. — Cream-white (dried). 
Habitat. — Mexico. 
Remarks. — The measurements of the spicules are taken from Bowerbank’s illustration. 
The generic position of the sponge is doubtful ; the groups of oscules are circumscribed by 
a definite margin as in genuine Geodias. 
Geodia (?) ramodigitata, Carter. 
Geodia ramodigitata, Carter, Ann. and Mag. Nat. Hist., ser. 5, vol. vi. p. 133, pi. v. fig. 31, 1880. 
Sponge. — Cylindrical, branching into finger-like processes ; surface covered with 
attached detritus ; oscules in groups or scattered singly ; pores in sieves, generally dis- 
tributed ; cortex, 1‘55 mm. in thickness. 
Spicules. — I. Megascleres. 1. Oxea, 1'77 by 0'056 mm. 2. Orthotrisene , rhabdome 
2’25 by 0'056 mm., chord 0‘338 mm. 3. Pro- and 4. Anatrisenes, cladi 0'056 mm. long. 
II. Microscleres. 5. Sterraster, ellipsoidal, 0T4 byOT12 mm. 6. Somal chiaster, 
0'0043 mm. in diameter. 7. Choanosomal chiaster, actines slender, not tylote, 0'034 
mm. in diameter. 
Colour. — In the dry state, grey. Size, 125 mm. long, greatest diameter 8 mm. 
Habitat. — Gulf of Manaar. 
Section 4. Monotrisena. 
Species possessing but one form of oxea and one form of trisene. Of these species there 
are but two, both incompletely characterised. It is therefore doubtful whether any of 
the Geodise really belong to this section. 
