1866.] MR. \V. T. BLANFORD ON OPISTUOSTOMA. 447 



Fam. Mutelid^. 



6. Spatha baikii, sp. nov. 



S. testa solidula, transversa, ovata, ventricosa, antice angusta, 

 rotundata, postice lata, subrotundata; margine dorsali arcuato; 

 margine ventrah in medio sinuato ; epidermide nigro-fusca ; 

 umbonibus antemedianis, inconspicuis, erosis ; margarita sal- 

 monaceo-purpurea. 

 Long. 120, alt. SO, lat. 45 mill. 

 Hab. River Niger. 



I have named this species after my lamented friend Dr. Baikie, by 

 whom it was collected. It differs from S. rubens, to which it ap- 

 proaches most nearly in form, in being more ventricose, broader and 

 more rounded posteriorly, and in having a greater sinuation of the 

 ventral margin. It is also a larger shell, and the epidermis is of a 

 darker colour. 



Note on Opisthostoma de-Crespignii. 



Since describing the shell of this species, some examples having 

 the animal dried within them have come into my possession ; and 

 by breaking one of them carefully and extracting the animal I have 

 ascertained that it is provided with an exceedingly minute and very 

 thin horny operculum. As, from its helix-like appearauce and very 

 elongated and porrected mouth, it is more singular even than the 

 type of the genus, O. nilgiricum, a figure of it is now given 

 (PI. XXXVIII. fig. 12), none having hitherto been published. 



M. de Crespigny has suggested that this genus may be identical 

 with the fossil Scoliostoma, which, however, has hitherto been re- 

 garded as marine. Its resemblance to the type of Scoliostoma, S. 

 dannenburgi, is very strong ; and if they are not generically the 

 same, the very singular fact must certainly be admitted that a group 

 of recent land-shells exists possessing this peculiar form in common 

 with a group of extinct marine shells. — H. Adams. 



11. On Opisthostoma, H. Blanford, with the Description of 

 a New Species from the Neighbourhood of Bombay, and 

 of the Animal and Operculum. By William T. Blan- 

 ford, Assoc. Roy. Sch. Min., F.O.S. 



(Plate XXXVIII.) 



To the keen search of one of the most indefatigable and success- 

 ful collectors of land shells in India, the Rev. S. Fairbank, is due 

 the very interesting discovery of a second species of the remarkable 

 Cyclostomaceous genus Opisthostoma, the type of which was first 

 found by my brother, Mr. H. F. Blanford, on the Nilgiri hills of 



