SOWEEBY : NEW SHELLS FKOM HONG-KONG. 159 



perforations, the first being a narrow slit about 2 mm. in length, 

 the second and third rather shorter, and the last two only about 

 •75 mm. The second specimen is about 47 mm. long, and has five 

 slits which are narrower than in the first, four of them being of 

 nearly equal length. The third specimen is a young one 28 mm. 

 long, having only two long narrow slits. A fourth specimen has 

 been for many years in the British Museum, unnoticed ; it is nearly 

 as large as my largest, and has four slits. 



It is at present uncertain how these perforations are formed. It 

 may be conjectured that when young there has been an open slit or 

 notch in the anterior margin, as in £marginula, which has been en- 

 closed in the next stage, as in Rmida, a succession being formed and 

 enclosed in subsequent stages. 



The animal is very like that of DentaUum entalis, and the Rev. 

 Prof. Gwatkin has examined the radula, finding it the same as in the 

 typical Bentalium. 



I am not quite certain as to the habitat of this curious Mollusc ; it 

 was not among those dredged by Dr. Hungerford, but I believe the 

 three specimens were found in the neighbourhood of Hong-kong. 



[Since the reading of this paper our President drew my attention 

 to the fact that the Rev. R Boog Watson, in his Report on the 

 Scaphopoda and Gasteropoda of the Challenger, p. 2, pi. i. fig. 1^, 

 noticed something on a very small scale approaching the character 

 here described in the case of a very young specimen of DentaUum 

 capillosum, Jeffreys. He says: "The young specimen from Station 

 78 has at the apex on the convex curve a slit 0"1 in. long, but 

 interrupted by two bridges of the shell which have not been removed 

 when the fissure was made."] 



Family PSAMMOBIID^. 



22. PSAMMOBIA. SIMPLEX, U.Sp. PI. XII. Pig. 21. 



Testa oblongo-ovalis, tenuis, albida, concentrice striata, utrinque 

 rotundata, latere postico obtusissime angulato, striis radiantibus paucis 

 obscurissimis sculpto ; umbones minuti ; ligamentum parvum ; dcntes 

 cardinales minuti. Longit. 9, alt. 5 mm. 



A small whitish species, oi a simple oblong form, concentrically 

 finely striated, with very obscure radiating striae at the posterior end. 



Family TELLINID^. 



23. Tellina Htjngereoedi, n.sp. PI. XII. Fig. 22. 



Testa sub-trigono-ovalis, tenuis, compressa, intus extusque albida, 

 antice latiuscula, postice acuminata, flexuosa, undique concentrice 

 lirata, liris anticis numerosis confertis, tenuissimis, posticis remotius- 

 culis ; margo dorsalis anticus convexiusculus, leviter declivis, posticus 

 leviter incurvatus, declivis ; umbones acuti ; ligamentum parvum ; 

 lunula elongata, angusta, impressa; dentes cardinales breviusculi, 

 acuti, laterales indistincti. Longit. 7, alt. 4-25 mm. 



A little flexuous shell with laminar ridges, which are twice as 

 numerous on the anterior as on the posterior half. 



