OF SOFTHERN INDIA. 
17 
V. DISCOPORA, Lamarck, 181G, (sec p. 9). 
1. Discopora obtecta, Sloliczha, PL I, Fig. 12. 
Lis. coloniis extensis, celluUs depressis planisque composiVis, hexagonis, plus mi- 
nusce elongatis, Iccvigatis atque carina elemta communi, medio obsolete sulcata, cir- 
cumdaiis; apertura mediocri, antica, sub-lerminali, transverse semiovata, marginihus 
paululum mcrassatis. Fissoribus elongate ellipticis, tdrinque acute termimmtibus, 
concavis, orificio ovato sid)-mediano instructis. 
The cells iu this species are almost regularly hexagonal, with the upper surface 
entirely flat, but calcareous, and as the aperture is comparatiyely small and sur- 
rounded l)y slightly thickened lips, I tliink it should he referred to the above genus. 
The ridges Avhich separate the cells arc very indistinctly furroAved along the crest, 
indicating the boundaries of each two adjoining cells. The slitters arc large, 
elongately ovate, AA'ith acute terminations, concaA'e aboA^e, and Avith a sub-median 
oval aperture. No ovicells or avicularia have been obseiwed. 
Localities . — Yermanoor and Chokonadapooram, forming rather cxtensiA'e in- 
crusting layers on Oysters. 
Formation . — Arrialoor group. 
VI. MEMBRANIPORA, Blainvilte, 1831, (see p. 10). 
1. Membraxipoba pedata, Stoliezka, PI. II, Figs. 2-3. 
Memb. cellulis depressis, plants, Icevigatis, plus minusve elongate hexagonis, lineis 
impressis separaiis, basi valde contractis, tectis, medio latissimis, jxirte anteriore 
modice angiistatis, nonnumiuam semiovatis ; apertura. fere dimidium longitudinis 
cellularum ocenpante, sub-ovata vel suh-pyriformi, antice paido angustata, marginibus 
declwibis, radiatini breciter striatis. Cellulis antiquis fere regulariter hexagonis, 
scepissime fere omnino convexiuscule tectis, quaque ostio minimo sub-mediano perforata . 
Cells depressed and flat, separated by A'cry fine impressed lines, elongately 
hexagonal, widest in the middle, much more contracted posteriorly than anteriorly. 
The length of the cells is subject to considerable variation, apparently depending 
upon the more or less plain surface which they incrust. The aperture is placed in 
the anterior half, and is OA'atc or somewhat pear-shaped, its upper part being slightly 
contracted ; its margins are finely radiately striated. In a colony the median or 
oldest cells arc generally almost regularly hexagonal, or at least much shorter 
than the yormger cells, and apparently AA'ith age they become enthcly covered AAuth 
a very slightly convex calcareous smooth membrane, perforated about the middle 
by a very small rounded opening, and many cells haA*e besides this another small 
opening in different places of the membrane, but generally sub-marginal. 
Locality . — Niunyoor, forming thin incrusting layers on Oysters. 
Formation.— A-VxidXooY grorip. 
E 
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