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Show 126 ZOOLOGICAL COLLECTIONS MA.DE DURING [Jan. 4, HENIERA FORTIOR, Schmidt? (Plate XI. fig. 3.) Beniera fortiori O. Schmidt, Spong. atl. Geb. p. 40. A poorly preserved spirit-specimen, which has lost most of the dermal membrane and much of the internal sarcode. Examined. In spirit and by mounting in balsam. External Characters. Form massive, irregular, subglobose, attached by a short pedicel about one fourth as broad as the greatest diameter of the Sponge. Texture very elastic. Colour semitrans-parent dirty white; surface in present state chiefly regularly and minutely hirsute. Minute Surface-characters. "Where the dermal membrane is present, this consists of a very thin brownish-yellow lamina, resting on the ends of the primary skeleton-columns, and formed by a skeleton network of 1- to 2-serial lines of fine acerate spicules, lying in a fine fibre, with meshes of 1| to 2 spicules' lengths in width, crossing each other at acute angles, the intervals being more or less occupied by fine and stouter acerates lying in the almost transparent, slightly granular sarcode which fills them. "Where this membrane is absent, the ends of the skeleton-columns project as fine pencils. Vents 1 apparently represented by 4 or 5 roundish apertures, of about 1 millim. diameter each, situated on a somewhat concave lateral surface ; they appear to lead directly inwards. Pores 1 apparently scattered or aggregated in twos, oval; largest diameter '045 millim. Main Skeleton. Composed, in the older parts, of Chalinoid fibre, containing only about half its hulk of horny matter ; in the younger parts a margin of this material is but rarely seen to surround the spicular axis; possibly this is partly due to imperfect preservation. Colour absent, or of the faintish possible tinge of yellow. Primary fibres contain a 2- to 4-, generally 3-serial axis of moderately stout, short acerate spicula; they run from the centre to the surface, meeting the latter approximately at right angles, and are distant from each other by 2 to 4 spicule-lengths. Secondary fibres at right angles to the primaries, usually composed of a double series of identical spicules ; occur at intervals of 2 to 3 spicule-lengths. Skeleton-spicules. Of one form-short stout acerate, slightly and gradually bent, or with a slight angle, tapering gradually to the points; size "13935 millim. long by '0094 broad. Flesh- and Dermal Spicules. O f one form-short slender acerate, slightly and gradually bent, tapering gradually to points; size of average largest "10135 millim. long by -0038 broad, in the case of the dermal, "1077 long by "006334 broad, in the case of the flesh-spicules, which latter are probably merely young skeleton-forms. Hab. Elizabeth Island, Straits of Magellan (eastern portion), sandy bottom, 6 fathoms. Chalina granti, Bowerbank, strongly resembles this Sponge in its chief essential characters; the main differences between the two are those of degree rather than of kind. Thus the skeleton-spicule measures "133 by "01056 millim., and is of the same type of acerate, though, as the measurements show, it is, although shorter, actually |