knoWP-^^V^<^^^^of Spongilla. 97 



covered with perpendicular spines, which are longest about 

 the centre (fig. 9, w). Statoblast elliptical, flask-shaped; 

 aperture terminal (fig. 9,^) ; crust thick, composed of granu- 

 lar microcell-substance (fig. 9, d) charged with ineequibirotu- 

 late spicules (fig. 9, e) consisting of a straight shaft, inflated 

 near the small end, and passing by trumpet-like expansion 

 into the large disk, sparsely spined (fig. 9, h) ; disk circular, 

 smooth, with even margin (fig. 9, z), small end consisting of 

 a circular convex head, regularly denticulated on the margin 

 with eight or more conical processes, which are slightly in- 

 clined towards the shaft (fig. 9, h, I) ; arranged perpendicularly, 

 so that the disk rests on the chitinous coat and the head forms 

 part of the surface of the statoblast (fig. 9, e). 



hoc. River Amazons. On a leaf sent to me by Dr. Dickie 

 in 1878. 



3. Tuhella reticulata. (PI. VI. fig. 8 a-w, and fig. 16.) 

 Spongilla reticulata, Bk., No. 20, p. 17, pi. xxxviii. fig. 9. 



Elliptical, or fusiform when growing round the immersed 

 small brandies of trees. Structure extremely rigid^ reticulate, 

 terminating in thorn-like processes on the surface. Colour 

 light sea-green when growing in clear water. Skeleton-spicules 

 curved or bent, cylindrical or subfusiform, rounded at the 

 ends, absolutely smooth or sparsely spiniferous (PI. VI. fig. 8,???, 

 and fig. 16), becoming more so towards the statoblasts, where 

 they are not more than half the size, thickly spined, and in 

 this shape form a distinct capsular layer around each of those 

 organs (fig. 8, Z, ii). Statoblast elliptical, ovoid (fig. 8) ; 

 aperture terminal (fig. 8,/) ; crust composed of granular 

 microcell-substance (fig. 8, d) charged with ineequibirotulate 

 spicules (fig. 8, e) consisting of a straiglit shaft passing by 

 tnimpet-like expansion into the large disk, with two or more 

 spines about the centre, and furnished with a ring-like inflation 

 towards the disk (fig. 8, h) ; disk circular, smooth, with even 

 margin, which is somewhat recurved (fig. 8, i), small end 

 consisting of a circular umbonate head regularly denticulated 

 on the margin with 6-8 conical processes, which are slightly 

 inclined inwards or towards the shaft (tig. 8, h) ; arranged 

 perpendicularly, so that the disk rests on the chitinous coat, 

 and the head or small end forms part of the surface of the 

 statoblast (fig. 8, e). 



Loc. lliver Amazons. 



Ohs. The skeletal structure of this species, although of the 

 same rigid nature and general character as that of Parmula 

 Batesii and P. Broionii, to be hereafter mentioned, is more 

 reticulated and not nearly so coarse as in the latter. 



