384 REPORT 1868. 



Taken in company with Isodictya laclniosa in 170 fathoms, 20-25 

 miles 1ST. by W. of Burrafirth Lighthouse, in 1867, and again in 1868. 

 A very large and thick 'species, growing in flat lobate masses. The 

 largest piece in my collection measures 11 inches long by 6| in its 

 greatest breadth. 



Genus OCEAKAPIA*, Norman, n . g. 



Sponge consisting of a hollow sphere filled with sarcode, surrounded by a 

 hard spongeous crust of a very close and compact nature. From the oppo- 

 site poles of the axis of the spherical or ovate body of the sponge there spring 

 more or less numerous simple or branched fistulaa of great size and length ; 

 these fistulaB are also furnished at their base with prolongations, which, pass- 

 ing inwards into the central cavity of the sponge in the form of cylindrical 

 branching tubes, are bathed in the great sarcodous mass. Skeleton spiculo- 

 fibrous, irregularly reticulated ; fibres polyspiculous, the primary lines, especi- 

 ally of the fistula, of great size. Spicula acerate, stout (Bowerbank, pi. i. 

 fig. 2) and very minute, in the form of half a ring, " simple bihamate " 

 (Bowerbank, pi. v. fig. 109). Dermal membrane reticulate ; rete for the 

 most part unispiculous ; spicula of the same two kinds as those of the 

 skeleton. 



Oceanapia Jeffrey sii (Bow.)=Desmacidon Jeffrey sii, Bow. Brit. Spongiadae, 

 vol. ii. p. 347, Isodictya robusta, ib. id. p. 304. 



In 1861 I dredged a portion of the spherical crust of this sponge, 

 from which the fistulas had been abraded. This having been placed in 

 Dr. Bowerbank's hands, was considered by him to belong to the genus 

 Isodictya, and is described in his work under the name I. robusta. In 

 subsequent expeditions to Shetland I obtained many detached fistuloe, 

 and also portions of the crust, which convinced me that the entire sponge, 

 when found, would prove to be something very different from what had 

 been imagined by Dr. Bowerbank from the type specimen. In 1864 

 some of the fistulaB were forwarded by Mr. Peach to Dr. Bowerbank, 

 who regarded them as a new species of Desmacidon (I). Jeffrey sii}. At 

 length, during the past summer, several perfect specimens of the sponge 

 have been dredged, and it is thus proved to be a remarkable species, 

 jperhaps the most interesting, as it is also one of the largest of British 

 rorifera. 



In form and size the adult sponge most strikingly reminds us of a full- 

 grown swede turnip. Imagine such a turnip to be going to seed, and to 

 have sent up several shoots. Now break these shoots off 4 or 5 inches 

 from the bulb, strip off the leaves as well as the smaller fibrous por- 

 tions of the roots, and scoop out all the interior of the turnip, leaving 

 only the rind, and you will have a very fair idea of Oceanapia. The 

 rind represents the spongeous crust ; the hollow interior is a cup filled 

 with sarcode ; the broken off stems are the cloacaB, which are of about 

 the size and shape of a finger, the smaller specimens having sometimes 

 only one, but the larger as many as a dozen such cloacal fistula of 

 various sizes, which are generally simple, more rarely branched. The 

 roots of the turnip represent other fistular appendages of smaller size 

 than those which spring from the crown, and of more solid and stringy 

 texture. These appear literally to take the place of roots, since in one 

 instance they grasp a pebble with their extremities, and in other cases 



* Oceanus and napus, a turnip. 



