Mr. Jeffreys on an undescribed Peculiarity in Teredo. 289 



diating beards. The tentacles are long and tapering, semi- 

 opake, white, with about five or six rather distant black rings. 

 The eyes are placed at the ends of stoat elongated peduncles, 

 the right free, the left attached to the pseudo-siphon ; the eyes, 

 at the apex of a white bulb, are of a dark brown colour, with a 

 small round black pupil. The white peduncles are stained with 

 dark brown just below the bulb. The funnel-shaped organ on 

 the left side is semipellucid, and furnished inside with numerous 

 opake white papillae; the edge is fringed, and adorned with 

 black dots. The neck-lappet on the right side is large, and 

 folded on itself, forming a conspicuous anal siphon flecked with 

 opake white, but sufficiently pellucid to allow the passage of the 

 faeces to be distinctly seen through the walls of the tube. This 

 organ is sometimes thrown up upon the back of the shell. 



The mantle, as might have been surmised from the polished 

 nature of the surface of the shell, is reflected over the front edge 

 of the outer lip, forming a narrow black rim, and, when touched, 

 is immediately retracted. The portion of shell covered by the 

 mantle is seen void of colour or markings on the perfect adult 

 shell. In cabinets the shell is rarely perfect, on account of 

 the thin, brittle nature of this part. The lateral membrane of 

 the foot is provided with four tentacular filaments, the two 

 posterior rather closer together than the two anterior. 



The foot is voluminous, with flat thin margins ; it is semi- 

 pellucid, and the operculum is placed on the dorsal surface, close 

 to the shell ; the hind part of the foot extends in the form of a 

 tail far beyond the operculum, and is triangular, flat above, and 

 angular at the sides, two dark lines meeting behind in a point 

 behind the flat area. The sole is greyish, with a median opake 

 white patch at the fore part, and with numerous very fine 

 radiating pencilled lines on each side ; a dark-grey median streak 

 extends from the white blotch as far as the end of the tail, and 

 in the middle part are one or two slender dark transverse lines. 



Any further observations on the anatomy and dentition I 

 must for the present reserve. 



Wei-hae-Wei, Shan Tung, China, 

 April 15, 1860. 



XL. — Notice of an undescribed Peculiarity in Teredo. 

 By J. Gwyn Jeffreys, Esq., F.R.S. 



On my return last week from the Continent, through Holland, 

 1 had the pleasure of meeting Dr. Verloren at Utrecht, and of 

 examining living specimens of Teredo marina which he had kept 

 in a glass jar for about ten months. They appeared to have be- 

 come habituated to the loudest noise ; and even when the jar was 



