1873.] DR. J. S. BOWERBANK ON THE SPONGIAD.E. 325 



there are a few of the tuberculated subcylindrical spicula that are so 

 abundant on the dermal membrane. 



Dictyocylindrtjs setosus, Bowerbank. (Plate XXX.) 



Sponge fan-shaped, branching dichotomously, pedicel short ; sur- 

 face setose ; setae long and very numerous, usually simple, some- 

 times 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 Quehett). 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 setse, 

 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 

 setae their spicula are dispersed on the interstitial membranes in the 

 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. 1 18, B. 1 1 7, 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 my collection which 

 he then presented to me. In accordance with these facts, I have, in 

 iny 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 my MS. 

 description ; and he took notes regarding it from my description of it 



