172 Mr. E. A. Smith on Mollusca from the 



Many of the species of the genus Limopsis are very much 

 alike, and it is chiefly on account of difference of locality and 

 form that they have been separated. The present species 

 considerably resembles L. pelagica, Smith, but is not of quite 

 the same form, has thicker, more solid valves, and a coarser, 

 more hairy epidermis. L. Cumingii, A. Adams, is also 

 closely allied. 



All the specimens are more or less coated with a rust-red 

 earthy deposit. 



28. Amussimn Alcocki. (PI. V. figs. 15- 16.) 



Testa fragilis, subdiaphana, albida, plus minus nitens ; valvae com- 

 pressae ; valva dextra fere plana, dilutissime subrosacea, concen- 

 trice striata, marginem versus lamellis tenuissimis ornata, sinistra 

 profundior, albo-pellucida, fere argentea, similiter striata, radi- 

 atimque exilissime lirata et striata, radiis tribus paulo prominen- 

 tibus posterioribus exbibens ; auriculae minimse, subaequales, lineis 

 incrementi, et liris vel striis paucis radiantibus subobsoletis 

 sculptae ; umbones acuti, ad angulum circa 115° convergentes ; 

 pagina interna nitida, liris undecim haud ad marginem extensis 

 (illis valvae dextrae paulo crassioribus) instructa. 



Longit. 40 millim., alt. 41, diam. 8. 



Hab. Laccadive Sea, in 740 fathoms ; also west of Anda- 

 man Islands, lat. 13° 47' 30" N., long. 92° 36' E., in 561 

 fathoms. 



The three slightly raised rays down the posterior side of 

 the left valve are indicated on the inner surface by corre- 

 sponding shallow depressions. 



The largest specimen from the latter of the above localities 

 exhibits rather more concentric lamellation on the left valve 

 than the examples from the Laccadive Sea. 



This species is very closely allied to A. Watsont, Smith, 

 but is not so rounded ; the right valve has more feeble con- 

 centric sculpture, and the radiating lines of the left valve are 

 not so strong. 



29. Amusstum andamantcum. (PI. V. figs. 13, 14.) 



Testa A. Alcocki simillima, sed minus circularis, angulo apicali 

 acutiore, lamellis valvae sinistrae magis prominentibus, lineis radi- 

 antibus fere omnino carentibus, lirisque internis gracilioribus, 

 praecipue illis prope medium valvarum plus minus obsoletis. 



Longit. 25 millim., alt. 33, diam. 6-5. 



Hab. Andaman Sea, in 688-922 fathoms. 



Both in this species and A. Alcocki the straight hinge-line 

 of the right valve is slightly serrated. The umbonal angle 

 in this form is scarcely greater than 90°, and the general out- 



