rg2i.] A. Robertson : Report on Bryozoa. 47 



26. Membranipora simplex, Busk. 



Nellia simpler. Bu'-k. 1852. pt. 1. p. 19, pi. Ixv, fig. i ; pi. Ixv (bis), fig', y, 



Obtained at Santapilly and at Madras. 



27. Membranipora tehuelcha, D'Orbigny. 



Mcnibninifiova tehuelchci, Robertson, lyoS, p. 265, pi. 15, figs. 16, 17; 

 pi. 16, fig. 18. 



More or less abundant at Puri beach, Orissa coast on bits of 

 \yood, also at station 380 (off Akyab, Burma, i9°8' N., 92°59' E.), 

 said to be dredged at 530 fathoms, but since the specimens were 

 growing on sea weed this is thought to be doubtful. [The weed on 

 which it grew commonh' floats on the surface. N. A.\ 



28. Membranipora tehuelcha var. intertuberculata, Waters. 



M. tehuelclia \ar. iiitertiibercttlata, Waters, 1898, p. 676, pi. 48, figs. I, 2. 



Obtained from two localities, Puri beach, Orissa coast and 

 from tide pools at Kyouk-Phyu, Burma. In the adult stage this 

 variety assumes a most fantastic appearance due to the elevated, 

 folded, spinous walls. The tubercles are often more numerous 

 and fantastic than represented by Waters, mere seasonal or 

 environmental variations, probablj^ of this cosmopolitan species. 



29. Membranipora trifolium var. minor, Hincks. 



Monbrnnipova trifolium \'ar. minor, Hincks, 18S5, ser. 5, vol. 15, p. 

 255, pi. \iii, fig. 7. 



Obtained at Mangalore at 31 fathoms, and at the Andamans ; 

 also off Cej'lon at 703 fathoms, growing on shell. 



30. Membranipora spinostoma, sp. nov. 



Zoarium loosely incrusting a stem. Zocecia irregularly quadr- 

 angular with a broad calcareous border crenulated on the inner 

 margin (fig. 5, A). Aperture membranous, occupying the whole of 

 the front. Operculum, large, with a heavy chitinous rim, opening 

 close to the calcareous border. The spinal adornment of operculum 

 and area constitutes the unique feature of this species. Spines occur 

 in three locations : (i) on the margin of the area ; (2) on the oper- 

 culum ; (3) below and at each extremity of the operculum. Spines 

 on the margin of the area, delicate, finely pointed, varying in 

 number from 12 to 15 placed regularly, to a few at irregular 

 intervals. Spines on the operculum (fig. 5, A, C) heavy, chiti- 

 nous, arranged in two rows, alternate, at least six, usuallj- eight 

 in number, one springing from near the base of the operculum, 

 the other about half way from the base, stiff, longer than the 

 width of the operculum, directed upward or toward and beyond 

 the distal border (C, op.sp.). Two lateral spines at the extremi- 

 ties of the opercular bar invariably present. These grow in 

 sockets and are movable in two directions, upward and downward. 



