251 



short principals, each of which bears 2 — 4 slender terminals ending in 

 an inverted bell -like umbel composed of 5 recurved and comparati- 

 vely long teeth (resembling the spicule represented in Schulzens 

 fig. U, PI. LXX, Chall. Report, Vol. XXI]. 



The total absence of proper autodermals indicate that this new 

 genus is to be classed among the Euplectellidae. 



Walteria Leuckarti n. sp. 



A very elegantly shaped species with a flat basal disc, about 

 120 mm in diameter, from which arises a slightly bent stem of the 

 thickness of a thumb to a height of over 790 mm. The stem sends 

 out, at about right angles and in all directions, numerous branches 

 (up to 132 mm in length) , that may bear secondary branches of variable 

 length. Thus the species has a shape not unlike that of a fir-tree de- 

 nuded of leaves. The surface of both the stem and branches shows a 

 number of small openings, the margin of which is more or less ele- 

 vated into a short tube. Such a tube invariably harbours a hydranth 

 of a commensal hydroid colony, as in JV. Flemmingi. The stem, but 

 not the branches, is hollow and possesses here and there large, round 

 or oval, sharp-edged openings, the oscular orifices. 



The principal parenchymals, extensively anchylosed on the stem- 

 wall, are diacts of variable size. These run in general longitudinally 

 in the stem-wall and in the axis of branches. The club-shaped distal 

 ray of sword-shaped hypodermals ends in a conical point and is beset 

 all over with scaly prickles. 



Rosettes are of three kinds: 1) spherical discohexasters (Chall. 

 Report, PL X, fig. 1); 2) large graphihexasters ; and 3) discohexasters 

 of the type of fig. 5, loc. cit. The last mentioned are but of very iso- 

 lated occurrence. It is remarkable that I have never met with flori- 

 comes in this species. 



More than five specimens had been obtained in all. 



Hyalascus sagamiensis n. gen. n. sp. 

 Through Mr. Owston's courtesy I have been able to examine 

 the only specimen, on which I base this new genus and species. It is 

 a comparatively thin-walled (up to 12 mm) sac of the shape of a vase, 

 bulged out at about the upper third of the body. Total length 500 mm; 

 greatest diameter 230 mm. The oscular region is irregularly expanded 

 and presents a thin simple rim without special marginals. The nar- 

 rowed inferior end is torn ofi". Texture of the sponge rather dense and 

 firm, although synapticular fusion of spicules nowhere occurs. On the 

 smooth dermal surface , a number of strands formed by certain sub- 



