60 



Descriptions of some Nkv/ Species of 

 Marine Mollusca from South Australia 

 AND Victoria. 



By Professor Ralph Tate, F.L.S., F.G.S. 



[Read October 2nd, 1888.] 

 Plate XI. 



Teredo fragilis, sj>ec. nov. Plate xi., figs, i-^a — 13^. 



Tube fragile, slender, simple, constricted at frequent intervals, 

 but not sejDtated internally ; siphonal end incompletely divided 

 leng-thwise. The shell olfers no distinctive character. 



Animal with united siphons, furnished with two small shelly 

 •clavate pallets, the stalk much attenuated, the enlarged somewhat 

 •compressed upper portion crowned with a cartilaginous crust, 

 which has a projecting horn at each end. 



Dimensions. — Length, 65 ; diameter of circular aperture, 4 -25 

 millimetres. 



Locality. — Burrowing with the grain of the wood of the wharf- 

 piles at Port Adelaide. 



Coelodon patulus, spec. nov. Plate xi., fig. i. 



Shell thin, pellucid-white, compressed, inequilateral, inequi- 

 valve ; right A^alve slightly convex, left valve flat in the dorsal 

 region, concave ventrally. Anterior side short, subacutely 

 rounded ; posterior side prolonged, patulously extended ventrally, 

 truncated. Post-dorsal line nearly straight, or slightly incurved, 

 bounded by a slightly depressed linear-lanceolate area. Umbo 

 depressed, rather acute, situated in the anterior one-fifth. Sur- 

 face distinctly concentrically wrinkled. 



Dimensions. — Antero-posterior diameter, 16-5; dorso-ventral 

 diameter, 9-5 ; sectional diameter of both valves, 1 millimetre. 



Localities. — Dredged in life from 10 fathoms at Wool Bay, St. 

 Vincent Gulf (McDougall and Matthews) ; dead shells dredged 

 from deep water, Investigator Straits (South Australian Museum). 



If Pandora trilineata, Reeve, from Ceylon, be a Coelodon, the 

 present shell may have to be referred to it, as the only external 

 •differential characters are a slightly ditferent shape (a straighter 

 hinge line and a more acute posterior margin) and the absence of 

 .a nodulose dorsal rib. 



Mactra Matthewsi, spec. nov. Plate xi., fig. 4. 

 Shell ovately trigonal, nearly equilateral, subtruncated behind, 

 'Obtusely rounded in front. The post-dorsal margin is straight 



