DE. W. BAIRD ON NEW TUBICOLOUS ANNELIDES. 17 



in the seas of the West Indies. In the collection of Annelides 

 belonging to the British Museum we possess several additional 

 species, found inhabiting coral in other parts of the world. One 

 of these was found on a coral reef in the Arabian Gulf, and, 

 in the structure of the operculum, &c., materially differs from all 

 that have been previously described. The following is its de- 

 scription : — 



5. Ctmospiea teicoenis, Baird. (PI. II. fig. 1, operculum.) 

 Branchiae in spiras quinque convolutae. Operculum magnum, cornibus 



tribus dentatis armatum. 



The branchiae are disposed in five whorls. The filaments are 

 densely plumose on one side and are of moderate length. The 

 operculigerous filament is thick and fleshy. The operculum is 

 large, nearly flat on the upper surface, and is armed with three 

 stout, irregularly-toothed horns. The collar is large and fleshy. 

 The spines of the thoracic segments are stout, rather short, and 

 yellowish-coloured. The abdominal portion of the body is about 

 2 inches long, smooth on the ventral surface with the exception 

 of a few longitudinal strong striae, and strongly and densely 

 striated across on the dorsal surface. The tube in which this 

 annelide dwells is large, nearly as thick as a man's little finger, 

 but so covered with coral deposit that it is very difficult to 

 ascertain its form. We possess in the British Museum only two 

 specimens of this animal, one of them being partly contained in a 

 fragment of its tube. The mouth of this tube seems to be nearly 

 round ; but the rest of it is so covered with madrepore, in a mass 

 of which it had apparently burrowed, that nothing more can be 

 seen of its structure. 



The whole animal is fully 3 inches long, tapered somewhat 

 towards the tail, and about the centre of the body is nearly 4 lines 

 in diameter. 



Hah. Djedda, in coral reef. From the Collection of Mr. Met- 

 calf. (Brit. Mus.) 



6. Ctmospira brachtcera, Baird. (PI. II. fig. 2, operculum.) 

 Brancliije in spiras quinque convolutae. Operculum magnum, cornibus 



duobus brevissimis irregulariter dentatis armatum. 



Amongst the numerous objects of natural history collected 

 during the surveying-voyage of H. M.S. 'Fly' by Mr. Jukes, 

 Naturalist to the Expedition, and transmitted by him to the 

 British Museum, are two specimens from Swain's Eeefs, on the 

 east coast of Australia, of the " animals of tubes that bore into 



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