DK. AV. BAIRD ON NEW TUBIOOLOUS ANNELIDES. 13 



tremity or mouth wheu the tube raises itself up from the shell 

 upon which it creeps, is corrugated transversely (the striae of 

 growth?), and is marked with a large, distinct canal or furrow, 

 running along the dorsal surface throughout its whole length. 



Of the three specimens we possess, one, the largest, is at- 

 tached to part of the shell of Haliotis australis, another to a frag- 

 ment of a species of Mactra^ and the third is coiled round a 

 species of Eleiiclms. 



They were all collected in New Zealand by Lieut.-Col. Bolton, 

 E.E., to whom I have dedicated the species. 



Grenus Placostegus *, Philippi. 



2. Placostegus cariniperus. Gray (sp.), Baird. 



Numerous specimens of this species of Annelide were brought at 

 diiferent times from New Zealand, and deposited in the national 

 collection, by the late lamented Dr. Andrew Sinclair, R.N., 

 Lieut.-Col. Bolton, R.E., the late Captain Sir Everard Home, 

 Bart., and His Excellency Grovernor Sir G-eorge Grrey. 



The tube or shell was briefly described by Dr. Grray in 1843, 

 in the ' Eauna of New Zealand' appended to Dr. Dieifenbach's 

 ' Travels in New Zealand.' As only the operculum was known at 

 that time to Dr. Grray, and as that resembles very much in form 

 the operculum of the molluscous genus of shells " Vermetus,''' he 

 described it under the name of Vermetus cariniferus. A similar, 

 and, I believe, the identical species has since that time been 

 described and the animal figured by Schmarda, in his ' Neue 

 wirbellose Thiere,' 1861, under the name of Placostegus ccertdeus. 

 My chief object in this brief notice is to give a few more parti- 

 culars with regard to this species, to correct the synonymy, and 

 to restore the specific name attached to it originally by Dr. Grray. 

 I wish also particularly to bring before the notice of the Society 

 the fact that the animal gives out a beautiful dye or colour. The 

 specimens which were the subjects of my examination had been 

 for a number of years in the British Museum, some having been 

 placed there in 1845, and others in 1847. Notwithstanding their 

 having been so long dry, when softened in water, taken out of 

 the tubes, and placed in spirits of wine, they imparted to the 



* The genus Placostegus was constituted by Philippi to contain those species 

 of Serpida which have a calcareous opercukim (approaching very nearly in form 

 to that of some of the Gasteropodous MoUusca) in the shape of a shallow disk, 

 entire at the margin. 



