28 



GUIDE TO THE COKAL GALLERY. 



High Case 



III. 



Table Case 



2 A, B. 



f\/v 



vv. 



1 



Fig. 8. Case III. ?>) comes from Japan. Specimens of the 



two species have been photographed together for 

 comparison. 



The fine specimen of Walteria JeiicJcarti, from 

 Sagami Bay, Japan (Fig. 9 ; and Case III. 3), 

 consists of a long hollow thick- walled tube rising 

 from a solid base, and with solid pinnate branches 

 arising from the tube at right angles ; the oval 

 sharp-edged openings in the wall of the tube are 

 oscules. The little elevations on the surface of 

 the branches are caused by a commensal zoophyte. 

 Rhahdocalyptvs victor (Fig. 10) and specimen in 

 Case III. 3, from the same locality as the previous 

 species, forms a deep thin-walled vase of felt-like 

 texture. 



The Ijeautiful Lace Sponge, Semferella schnltzei 

 (specimens in Case III. 1, and Table Case 2b), 

 has a straight or curved conico-cylindrical body 

 terminating below in a massive root-tuft. The 

 surface shows a delicate gauze-like network, the 

 dermal membrane (Fig. 11), and also long bands 

 and patches of coarser pattern ; the latter are sieve- 

 plates covering the oscules. In place of a simple 

 central cavity with one terminal oscule and sieve- 

 plate, as in Venus' Flower-Basket, there is a main 

 central cavity giving off lateral branching tubes, 

 the surface-openings of which are covered with the 

 sieve-plates ; accordingly currents enter the fine 

 gauze-like areas and leave by the coarser sieve- 

 plate areas. 



Hijalonema sieboldU, or the Glass-rope Sponge 



(Figs. 8, 12) and specimen in Case III. 3, comes 



from Japan, closely allied species, however, being 



widely distributed. When the glass ropes (without 



the upper portion of the sponge) first arrived in 



Europe, they were supposed to be either artificial 



productions or the axial coxe of Gorgonid Corals. 



The twisted strand or glass rope is a root-tuft 



composed of immensely long spicules, which root 



the sponge in the mud, and which, at the upper 



end, project like a spike into the interior of the 



y sponge-body. Some of the long spicules end in a 



Lower end of a spi- toothed disk, and are provided along their length 

 cule of the glass 

 rope maguified. 

 a, axial canals of 

 five aborted rays. 



a 



