322 BULLETIN 100, UNITED STATES NATIONAL MUSEUM. 



way) through the sterrastral layer. Scattered scantily through 

 choanosome. 



5. Oxyaster. (a) Small form (pi. 47, fig. 8, b) about 8 [x total 

 diameter. Centrum well developed. Rays slender, fairly numerous ; 

 ray length about one-third diameter of the whole spicule. Com- 

 mon in ectosome and choanosome; lining cortical canals, except in 

 the uppermost part of canal, (b) Larger form (pi. 47, fig. 8, c), 

 16-28 [jl total diameter. Rays frequently about 12 in number, long 

 and slender, in the larger spicules roughened. Centrum small. 

 Common in choanosome. The two types intergrade, as indeed do 

 the spherasters and the small oxyasters. 



Holotype.— Cat. No. 21295, U.S.N.M. 



Genus GEODINELLA Lendenfeld (1903). 



Qeodinella Lendenfeld, 1903, p. 117; 1910, p. 205. 



With reduced triaenes arranged radially in the periphery of the 

 sponge and occurring also in the interior. Clads of triaenes re- 

 duced to two or one or none, the spicule appearing as diaene, 

 monaene, or style (tylostyle) ; even when present the clads are de- 

 generate in size, often very degenerate. 



The genus was established for Geodiaf cylindrica Thiele (1898) 

 from Sagami Bay, Japan. Lendenfeld in his first definition (1903, 

 p. 117) described it as a genus in which the triaenes lie in the in- 

 terior, arranged in longitudinal bundles constituting an axial 

 skeleton ; with spheroidal or ellipsoidal sterrasters ; and in which the 

 dermal microsclere is an elongated euaster, somewhat streptaster- 

 like. With the discovery of a second species, Lendenfeld found it 

 necessary to emphasize points other than those which he had first 

 picked out. His second diagnosis reads : " Without regular triaenes. 

 The tetraxon megascleres are monaene or diaene teloclads with re- 

 duced clads, and occur not only in the superficial part of the sponge 

 but also in the interior." 



GEODINELLA SPHERASTROSA, new species. 



Plate 38, fig. 3 ; plate 47, figs. 4, 5, 6, 7. 



A fragmentary specimen from station D5312, apparently about 

 one-half of a sponge that was more or less spheroidal or thick 

 cushion-shaped, with a horizontal diameter of about 37 mm. What I 

 interpret as the upper and the latero-inferior surfaces have different 

 curvatures and are separated by a margin which is rounded and 

 vague (pi. 38, fig. 3, right). The upper surface (pi. 38, fig. 3, left) 

 bears low rounded oscular elevations, 2.5 mm. in diameter, each 

 pierced with a central, very small, osculum; the largest of the oscula 

 0.5 mm. in diameter ; interval between neighboring oscular elevations 



