156 U.S. NATIONAL MUSEUM BULLETIN 2 72 



the type species of which was established by de Laubenfels (1936) 

 as S. brownii Bowerbank. 



Drulia brownii (Bowerbank), D. geayi (Gravier), D. cristata 

 (Weltner), and D. batesii (Bowerbank), even though poorly rep- 

 resented in the material for this study, will be dealt with below. 

 However, no attempt can be made at the present to document their 

 intrageneric relationship which cannot be resolved without access 

 to additional data. D. rusbyi (Potts), relegated to varietal rank by 

 Gee (1931e), and D. brownii tuberculata (Potts) have not yet been 

 examined by the present authors. 



Drulia brownii (Bowerbank, 1863) 



Plate 15, figukes 1-3, 7 



Spongilla brownii Bowerbank, 1863, p. 457. 

 Drulia brownii Gray, 1867, p. 552. — Penney, 1960, p. 39. 



Parmula brownii Carter, 1881a, p. 99. — Potts, 1887, p. 257. — Weltner, 1895, 

 p. 114.— Arndt, 1930b, p. 48.— Schroder, 1932a, p. 161.— Gee, 1932c, p. 35. 



Material. — Slides of type (BM) and syntype (ZMB); material 

 and slides from Brazil (N. Gist Gee no. 54687). 



Description. — Sponge forming nodulose, subspherical to spherical 

 growths, usually embracing submerged branches of trees; surface 

 coarsely reticulate and hispid, due to projection of thornlike spicule 

 fibers through dermal membrane. Skeleton consisting of thick and 

 strong radial spicule fibers, arising almost perpendicularly from base, 

 and of somewhat slimmer transverse fibers; both forming an open 

 but very firm and compact network of wide meshes. Consistency of 

 dry sponge very rigid to extremely hard. 



Megascleres rather stout and cylindrical to broadly fusiform amphi- 

 oxea with abruptly pointed tips, of two distinct lengths, entirely 

 smooth; length range of longer series 300-400 /x, of shorter 210-290 ju; 

 width range of longer series 28-32 n, of shorter 22-28 ju. 



Microscleres not very abundant in symplasm, or in the vicinity of 

 gemmules; they are thin and sharply pointed amphioxea, almost 

 straight or only feebly curved, covered with smaller spines at their 

 tips and Avith larger erect spines in their central portion; length 

 range 45-70 //, width range 3-5 n. 



Gemmoscleres typically parmuliform, rotide with internal conical 

 depression and with slightly recurved margins, in lateral view dis- 

 tinctly umbonate; margins ranging in shape from almost circular to 

 irregular, diameter of rotule 25-28 /z. 



Gemmules enclosed in cages of the smaller series of megascleres, 

 spherical, and very large; ranging in diameter 580-700 ix', pneumatic 

 coat comparatively thin and granular; parmuliform gemmoscleres 

 embedded in this layer strictly radially, with their rotules resting on 



