Report on the zoological collections made in the Indo-Pacific Ocean ...

412 COLLECTIONS FROM MELANESLV.wide apart, vertical to surface, 3 to 8 spicules broad ; secondariesat less intervals, 3 to 6 spicules broad ; the interstices occupied bymuch irregular 1- or 2- serial network. Dermal skeleton of stoutspiculo-fibre, similar to that of main skeleton ; the spicules 3- to8-serial, forming a network of subrectangular meshes, '4 to •? millim.wide, enclosing detached or loosely aggregated spicules. Sarcode verypale yellowish brown, slightly granular. Spicules smooth acerate,slightly and gradually curved, tapering to sharp points from aboutthree diameters from ends (varieties occur having one end taperingmoreor less to a blunt rounded extremity, or with one end roundedand as stout as the middle of the spicule, thus becoming trulyacuatc) ; size '2 by •0127 millim.Bah. Port Darwin, 7 fms. ; bottom sand.This species is perhaps allied to Reniera aquceduchts. It differsfrom that species in the anastomosing and externally spinous tubesand in the superior diameter of the spicule, which does not exceed•0095 millim. in that species. The specimen forms a low hedge-likeseries of anastomosing tubes, which are almost horizontal at theirlower ends ; maximum height of colony 55 millim. (2Jl inches),It has a remarkablemaximum lateral extent 100 millim. (4 inches).external resemblance to a form of the Chalinid, Tuba ac^qjulcensis,Carter.46. Pellina aliformis. (Plate XXXIX. fig. ;Plate XLI. fig. «-.)Erect, with slender pedicle ; expanding into one or more wing-likelobes, 4 to 6 millim. thick, 14 to 20 millim. in greatest width ; thefree edges looking upwards and downwards respectively and the apexdirected horizontally. Surface more or less roughened (especiallyon the flat surface of the lobes) by the conuli, about •G millim.apart, which enclose the ends of the primary skeleton-fibres ; themargins of the lobes, and sometimes their sides, are covered by aglabrous semitransparent membrane. Vents few, suboval, 2 millim.in greatest diameter, with thin membranous margins, generallyplaced on the edges of the lobes; their cavity oblique, entered bynumerous excretory canals. Texture in spirit brittle, slightlyelastic ; colour very pale brown.Main skeleton— spiculo-fibres loose, no perceptible horny unitingsubstance ;primary fibres approximately vertical to surface, '6 to•85 millim. apart, 8 to 10 spicules broad ; secondary fibres atvarious angles to primaries, at some distance apart, about 5 spiculesbroad. Dermal skeleton thick, formed of very loose spicular tractsof various sizes, crossing each other at various angles, leaving smallspaces between them. Sarcode rather granular, pale brown. Spiculessmooth acerate, slightly curved, tapering to sharp points from nearcentre ; size ^5 by ^025 millim.JIab. Port Darwin, 8-12 fms. ; bottom sand and mud.lleprescntcd by one whole specimen and one fragment, in spirit.The former 33 millim. high by about the same wide, and formed