found G7t the coast of Northumberland and of Durham. 237 



tion from the nature of the object it grows upon*," there is a 

 probability that it may be a variety of this species. It is nine 

 inches long, branched, flattened, dense and incompressible, at- 

 tached to a specimen of Fusus islandicus, and of a dirty light brown 

 colour. Only one side, which is slightly convex, has orifices; 

 these, as in Halichondria ficus, are " very few, small and scat- 

 tered :" the opposite side is flat, and has evidently rested on the 

 ground; at least it is impossible to conceive that the Fusus 

 islandicus could support so large and heavy a sponge in an erect 

 position. It was brought up by the lines from deep water off 

 the coast of Northumberland. 



Retepora BEANiANAf, nobis. 



Specific Character. — Coral white, cup-shaped when young, after- 

 wards irregularly and deeply folded ; adhering to foreign bodies 

 by a very short stalk ; with meshes and interstices similar to 

 those of a perforated strainer. Meshes longitudinally oval, 

 a little narrower than the interstices, and somewhat quincun- 

 cially arranged. Inner surface of the coral celliferous. Cells 

 (polypidoms) tubular, and arranged in linear series, of which 

 from four to six occupy the width of an interstice. Cell- 

 apertures in quincunx order, which is only slightly broken by 

 the meshes : upper lip with an intumescence having a medio- 

 longitudinal fissure : under lip with a central tubular process 

 having a round terminal opening : sides, each with a long 

 slender hollow spine. Front wall of the cells transversely con- 

 vex, and with one or two foramina of the same diameter as the 

 tubular processes. Outer surface of the coral marked with ir- 

 regularly flexuose and anastomosing lines running somewhat 

 longitudinally. Polyps of a red colour. 



Dr. Johnston and others have considered this coral to be iden- 

 tical with the Mediterranean Retepora cellulosa, but after an ex- 

 amination of the characters of each, I have been led to conclude 

 that they are distinct species. In the Mediterranean coral the 

 interstices of the celliferous surface are furnished with strong 

 hook-shaped processes curving upwards — generally two on each 

 side of a mesh, but nothing of the kind is seen in the Bri- 

 tish species ; and the under lip of the cell-apertures is not pro- 

 vided like the latter with a tubular process. Further, Retepora 



the North Sea for the trough separating the coasts of Northumberland and 

 Durham from the Dogger and Great Fisher banks seldom exceeds eighty 

 fathoms. 



* Dr. Johnston's British Sponges, 8ic, p. 146. 



t I feel much pleasure in naming this coral after Mr. Bean, who was the 

 first to discover it in the British seas (vide Loudon's Magazine of Natural 

 History, vol. vii. pp. 638 and 639). 



