,^-_„ 1 - "*Xlu"^»C ~* 



THE SPONGES. 



35 















1880. 



1887. 

 1901. 



Regadrella 0. Schmidt. 



Regadrella phoenix 0. Schmidt, 1880, p. 61 

 Regadrella 0. Schm., Schulzc, 1887, p. 84. 



Ijima, 1901, p. 220. 



Regadrella, sp. 



Plate 9, Fig. 9. 



Station 3380, two fragmentary specimens including only the macerated 



skeletal framework. 



In both specimens the base is preserved with the lower part of the tube 

 wall. The better specimen is figured (slightly above the natural size, owing 

 to an accident in the taking of the photograph). In the other specimen 

 the base is smaller, and less of the wall is included. The base in each is a 

 nearly flat plate with few irregularities. The skeletal strands forming the 

 wall are cemented together at the points of crossing, and the wall as a whole 

 is somewhat flexible and elastic. 



I have had for comparison specimens of B. okinoseana Ijima and JR. phoenix 

 O. Schm. As compared with the former species, and in a less degree as 

 compared with the latter, the " Albatross " specimens are remarkable for the 

 thin character of the parietal strands and the consequent large size of the 

 meshes. As compared with the only other species of Regadrella the whole 

 body of which is known, B. kameyamai Ijima, it would seem from Ijima's 

 description (1901, p. 257) that the parietal strands in my specimens undergo 

 a more extensive fusion. These specimens again differ from the described 

 species of Begaclrella in the greater regularity of arrangement displayed by 

 the skeletal strands. On the gastral surface the obliquely transverse 

 beams, which are very strongly developed, are arranged parallel to one 

 another. Crossing them at about right angles are ascending bundles. The 

 meshes would thus be squarish, but oblique fibres extending both to the 

 right and left cross the meshes usually at the corners, thus giving rounded 

 apertures. The oblique fibres may cross the middle of the mesh in such a 

 way as to obliterate the aperture. The arrangement of the skeletal strands 

 thus approaches the regularity found in Euplectetta. 



The coarser skeletal strands are made up, each, of one or a few large 

 diacts surrounded by very slender diact comitalia, all united by and 

 covered with cement. The principal diacts are 120 ^ or somewhat less in 





■MB 



