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

;340 COLLECTIONS FROM MELANESIA,somo small bad specimens ; they are respectively 200 and 220millim. (8 and 9 inches) long, extreme lateral extension in the naturalstate probably about 70 millim. (3 inches). This variety is remarkablefor its varia])ility in external characters, for the great relativelength of the terminal branches, and the early stage at which branchingcommences, and by the ridged character of the face of the Blattkeulespicule ; in most other respects it closely approaches thefollowing variety.Plexaura prselonga, var. cinerea. (Plate XXXVIII. fig. h.)Growth upright, in one plane. Stem long. Branching approximatelydichotomous ; branches few, flexuous : terminal branches 100to 150 millim. (4 to 6 inches) long ; stem and branches cylindrical,approximately of one diameter, viz. aboiit 2*3 millim., throughout.Cortex minutely rough, even, fairly tenacious. Colour in drystate dark dirty grey. Verrucoe small, slightly projecting from thesurface as low mounds, their openings extended in direction of lengthof branch; about 1 millim. distant from each other, equally distributedall over cortex. Axis tough, flexible, glossy dark brown.Cortical spicules (i.) :— Long fnsiform, approximately straight,tapering to sharp points, with scattered, tapering, sharp, simpletubercles ; size -21 to -35 by -07 millim. (ii.) Stout fusiform-cylindrical,curved, rather thickly covered with low compound tubercles,often extended in direction of circumference of spicule, with pointedends ; size about -3 by -12 miUim. (iii.) Irregular tri- to sexradiate,the arms cylindrical, blunt, covered with few and scattered,mostly low and blunt tubercles ; maximum diameter of spicule•18 to -21 millim., thickness of arms -042 to -053 millim. (iv.)Blattkeule, extremely variable, in form ; shaft provided with verystout neck, generally branching into two (occasionally three) stoutarms ; the latter are well covered with compound, rather angulartubercles, the neck and proximal part of foliar portion bearingbroader, more fungiform tubercles ; the foliar portion is flattenedin one plane, and either transversely oblong with four roundedangles, or cordate with sharp lancet-like extremity, or with thelower extremity prolonged into several long teeth ; the edges arethin and always more or less dentate, at any rate at the outerextremity, with small teeth ; the proximal part of the face carries,as already mentioned, a few large, fungoid, compound tuberclesone variety which has the edges much dentate has also a numberof small tubercles extended almost as far outwards as the edges.Size of spicule about -35 long by -35 millim. broad.Ilab. Port Curtis, Queensland, 5-10 fms. ; bottom sand andshells.This variety is represented by a single dry specimen, measuring230 and 180 millim. (9 and 7 inches) in extreme height and diameterrespectively. It differs from var. tyj^ica chiefly in the tubercnlaterather than ridged character of the faces of the "Blatt" of theBlattkeule spicule.