PORIFEEA OF THE L.M.B.C. DISTRICT. 217 



of Anglesey. The first specimen was got in Penrhos Bay, 

 from a depth of about ten fathoms. More material was 

 taken off Towyn (twelve fathoms), and lastly off Khos- 

 colyn Beacon (twelve fathoms) the dredge brought up a 

 specimen larger than any sponge ever found in our district, 

 and probably not exceeded in size by any sponge ever col- 

 lected on the British coast. It measures horizontally 31 

 cm. by 20 cm., and vertically 12 cm. The figure on PL 

 XII. represents the specimen in not quite one-half natural 

 size. I drew it from a photograph wliich Mr. Benjamin 

 Davies (Physical Laboratories, University College, Liver- 

 pool) had kindly taken from the specimen after it had been 

 in spirit for some time. Those members of our expedition- 

 who attempted to photograph it on board of the " Hyaena" 

 were less successful. 



The colour of the largest and of most of the smaller 

 specimens, when alive, was ochreous-yellow. But the 

 first specimen which we got from Penrhos Bay, was dis- 

 tinctly sulphur-yellow. The oscula are large and well 

 marked. They have the shape of slits, and measure from 

 2 by 1 mm. to 8 by 3 mm. Two of them are seen in the 

 figure upon one of the smaller lobes. A row of oscula on 

 the upper edge of the largest lobe could not be represented 

 in the figure. The pore-areas form extremely numerous 

 and well-marked circular patches (2 mm. in diameter) on 

 the extremity of very short papillae, just projecting beyond 

 the level of the sponge. In the " sinuous" form of Cliona 

 celatd those little papillae with their pore-areas are generally 

 the only things which are visible inside of or projecting 

 from the smal circular holes of the inhabited and perfor- 

 ated shell. 



The spicules are tylostyli. They measure 0315 mm. by 

 0-008 mm. A few of them were smaller, down to 0-225 by 

 0'003 mm. A vertical section through the sponge shows 



