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Show 1873.] DR. J. S. BOWERBANK ON THE SPONGIADcE. 325 there are a few of the tuberculated subcylindrical spicula that are abundant on the dermal membrane. DICTYOCYLINDRUS SETOSUS, Bowerbank. (Plate XXX.) Sponge fan-shaped, branching dichotomously, pedicel short; surface setose; setae long and very numerous, usually simple, sometimes branching dichotomously, projected ascendingly, composed of numerous stout acerate spicula disposed in parallel lines. Oscula and pores inconspicuous. Dermal membrane pellucid, spiculous ; spicula acerate, like those of the setae, few, dispersed. Skeleton- spicula of the axis cylindrical, long, somewhat slender, and more or less flexuous. Interstitial membranes abundantly spiculous ; spicula acerate, the same as those of the setae, occasionally reticulating. Colour, in the dried state, ochreous yellow. Hab. Bere Regis, Devonshire (Mr. John Quekett). Museum Royal College of Surgeons. Catalogue of Porifera, part i. 1860, p. 118, B. 117. Examined in the dried state. The sponge is 5*| inches high and 6 inches broad. It is of a thick and somewhat irregular fan-shape, and the whole of the sponge, excepting the short pedicel, is thickly covered with setae, which are frequently as long as the diameter of the branch, and nearly equal in diameter throughout their whole length; they terminate rather obtusely, occasionally dividing dichotomously near the distal termination. The spicula of which they are composed are about half the length and twice the diameter of those of the skeleton-axis. Where the spaces between the branching setae are somewhat wide, the interstitial structures frequently assume very much the aspect of a Halichondroid reticulation ; but towards the terminations of the setse their spicula are dispersed on the interstitial membranes in tbe same manner as those of the dermal membrane. I am strongly of opinion that the habitat assigned to D. setosus in the ' Catalogue of Porifera,' part i. 1860, p. 118, B. 117, is erroneous, and that the sponge there described is not a British species; and I believe that the habitat " Bere Regis " should have been applied to a specimen of Dictyocylindrus hispidus which Mr. Quekett informed me he had found on the coast of Devonshire. I saw specimens of that species in his possession, and I have one in m y collection which he then presented to me. In accordance with these facts, I have, in my description of D. hispidus, vol. ii. p. 108, Monograph of British Spongiadae, given his authority for the coast of Devonshire as a habitat of the species. It is most probable that the habitat " Bere Regis" should have been applied to the sponge B. 118, p. 119, of the Catalogue, which seems from the description to be a specimen of D. hispidus, Bow., or Halichondria hispidus, Johnston. When I described and named the sponge D. setosus at the Museum of the Royal College of Surgeons, Mr. Quekett told me that the locality was unknown, and I entered it so in m y MS. description ; and he took notes regarding it from my description of it |