STAIIROCALYPTUS GL AB ER. 



209 



fig. 3. They are both of an ovoid shape, growing side by side 

 on a dead Clionelasma calyx. One is 38 mm. and the other 32 

 ram. hio'h. The hitter shows an oscnhnn of G mm. dia. Fine 

 and long prostal needles, springing ont isolatedly and directed 

 ontwards and upwards, are present in moderate numbers. They 

 occur more especially in the upper half of the body. Some of them 

 may be 14 mm. long. From the constant absence of pentactinic 

 prostalia and from the peculiarly cavernous appearance of the 

 wall, I find it easy to distinguish the young of this species from 

 those of certain other discoctasterophorous species, such as Rhab- 

 docalyptus victor (PI. XIX., fig. 17) and B. capillatus (PI. 

 XXII., fig. 3-5). 



One more specimen (text-fig. 7) requires special mention as 

 being highly remarkable in more tlian one respect. The sponge- 

 body (64 mm. long and 27 mm. by 37 mm. broad 

 in the middle) presents the appearance of run- 

 ning out basally into a root- tu ft consisting of a 

 number of strong needle-like spicules, instead of 

 being firmly fixed to a hard substratum as in 

 all other specimens of the species. F. E. Schulze 

 (Chall. Kep., p. 41) conceived the idea that with 

 difiei'ing conditions of the sea-bottom, it was 

 possible for one and the same species to produce 

 Text-fig. 7. a root-tuft in one case and not in another. This 

 s. giaher growing on assumptlou of F. E. Schulze's I at first thought 



basal spicules of Hya- 



lonema sp. (S. M. No. had becu actually realized in the case under 

 Ma'; isofaToat^de Consideration ; but this proved to be simply an 

 Okinosé). illusion, for by microscopic observations it could 



clearly be demonstrated that the tufted spicules at the basal end 

 of the specimen do not belong to that sponge and are nothing 



