84 Eev. T. Hincks's Contributions towards 



Perhaps one of the most characteristic features of the species 

 is the glossy smoothness and whiteness of the zoarium. 



Membranipora villosa, n. sp. (PI. X. fig. 8.) 



Zocecia membrano-calcareous, elongate, rectangular, dis- 

 posed in lines, with a membranous front wall, margins thin ; 

 inner surface of the cell-wall crenate ; two acuminate spines, 

 one on each side at the top, and frequently a broad, membra- 

 nous, strap-like process between them, usually a smaller spine 

 on each side a little below the top ; front wall covered with 

 delicate spinules. Avicularia none. Ocecium (?). 



Loc. California, incrusting weed {Miss Jelly). 



This species is remarkable for the profusion of spinous 

 processes with which it is furnished. The zocecia seem to be 

 very slightly calcareous ; and the spines are simply membra- 

 naceous, and, when dried, are more or less shrivelled and bent. 

 In the centre of the upper margin there is often one of the 

 broad, strap-like spines which are so characteristic of the 

 species ; they run to a point above, and in the dry state are 

 flattened and present a bright and glossy surface. 



The front wall is rather thickly covered with slender sharply- 

 pointed spinules. 



a'. Cell prolonged below the aperture. 



Membranipora dtstorta, n. sp. (PI. X. fig. 7.) 



Zoo?cia ovate or subturbinate, prolonged below the aperture, 

 quincuncial, disposed with great regularity ; walls white and 

 rather silvery, covered with minute perforations ; aperture 

 oval, occupying about three fourths of the front of the cell, 

 with membranous covering, surrounded by a smooth, thick- 

 ened, and somewhat sinuated rim, bearing three spines, two a 

 little below the top, which almost meet across the area, and 

 one near the bottom on the outer side, calcareous towards the 

 base, with membranaceous extremities ; the zocecia as if heeled 

 over towards the inner side, so that the aperture appears some- 

 what distorted, the lower extremity pointing inwards and in 

 contact with the wall of the neighbouring cell ; at the top of 

 each cell a smooth semicircular space, slightly hollowed, en- 

 closed by a narrow edging, forming a kind of alcove. Avicu- 

 laria none. Ocecium (?). Zoarium branched j branches of 

 varying width. 



Loc. Ceylon, on weed (Miss Jelly). 



This is a remarkably beautiful species, and I have hesitated 

 to give it a name which might seem to imply the contrary. 

 Of course it merely refers to the curious twist of the cells, 



