KEPORT ON THE TETRACTINELLIDA- 
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2. Orthotrisene, rhabdome tornote or sometimes strongylate ; cladi geniculate. 
Khabdome 1’625 by 0’05 mm., cladi 0’12 mm. long, chord 0’22 mm. 
3. Anatrisene, rhabdome slender ; cladi prolonged backwards a considerable distance. 
II. Microscleres. 4. Ectosomal chiaster, with thick bacillary actines, rounded at the 
ends, very similar to a pycnaster, 0’0156 mm. in diameter. 
5. Choanosomal oxyaster, with few long slender actines and no centrum, frequently 
reduced to a triradiate form ; a single actine 0’0276 mm. in length. 
Colour. — In spirits, light green. 
Habitat. — Off Guernsey (Saville Kent). 
Remarks. — The anatrisenes must be extremely rare or local in their distribution, none 
are to be seen in the preparations which I made from the type specimen in the British 
Museum. The characters of the cortex are not clearly shown in these preparations, but 
it appears to consist chiefly of coUenchyma. 
Stelletta collingsii (Bowerbank). 
Tethea collingsii, Bowerbank, Brit. Spong., vol. iL p. 87, 1866 ; vol. iii. p. 37, pi. xv. 
figs. 1-9, 1874; and vol, iv. p. 44, 1882. 
Collingsia sarniensis, Gray, Proc. Zool. Soc. Bond., p. 541, 1867. 
Tethea schmidtii, Bowerbank, Brit. Spong., vol. ii. p. 89, 1866 ; vol. iii. p. 38, pi. xv. figs. 
10-16, 1874; and vol. iv. p. 44, 1882. 
Collingsia schmidtii, Gray, Proc. Zool. Soc. Bond., p. 541, 1867. 
Sponge. — Massive, sessile ; oscules and pores (?) ; cortex thick (?). 
Spicules. — I. Megascleres. 1. Oxea, I '96 by 0’032 (s) to 2‘44 by 0'0434 mm. (c), 
2. Orthotrisene; rhabdome 1’27 by 0'0478 mm, (s) to 1’6 by 0‘055 mm. (c) ; 
cladome, chord 0*23 [s) to 0'175 mm. (c). 
II, Microscleres. 3. Ectosomal chiaster, actines variable in number, usually four, 
tylote terminally; 0'0158 mm. in total diameter. 
4. Choanosomal oxyasters, two varieties, both with conical sharply-pointed actines. 
In the one the actines are large and few, 0'02 mm. long ; in the other small and 
numerous, O'Ol mm. long. 
Colour. — In the fresh state somewhat green externally, light grey within ; when 
dried, dull ochre-yellow. 
Habitat. — The English Channel, Guernsey, Sark, Herne, Torbay ; and Westport 
Bay, county Mayo, 
Observations. — The letters “ (c) ” and “ (s),” given after the above measurements, 
indicate the specimens from which they were taken ; “ (c) ” stands for Stelletta [Tethea) 
collingsi from Sark, “(s)” for Stelletta [Tethea) schmidtii. The dimensions of the 
spicules in specimens of Stelletta [Tethea) collingsii from Mayo differ from the foregoing. 
(zool. chall. exp. — PART Lxiii. — 1887.) Err 24 
