1901.] MOLLUSKS FROM TIIE PERSIAN GFLF. 367 



ElSSOFNA AMBIGFA Gould. 



I. Bombay. Old record. 



Eeported from both Aden and Ceylon. There are no typical 

 specimens in the Indian Museum, Calcutta, from our area (<■/. 

 G. Nevill, Hand-list of Mollusca, Calcutta, 1885, p. 73.) Of the 

 var. perpusilla Nevill, examples occur from P.O. Henjam I., and 

 I. Bombay, collected by Mr.' W. T. Blanford. 



Rissoina micans A. Ad. 



P.G. Tumb I., Kishm I., and Mutef (TT. T. Blanford in 

 G. Nevill, Hand-list). Gulf of Oman, lat. 26° 23' X., long. 56° 

 53' E. ; also lat. 24° 44' N., long. 55° 56' E. 205 fathoms. 

 Var. perstriatula Nevill. 

 P.G. Tumb I. (TF. T. Blanford, 1. c). 

 Bissofna sceptrum-regis, sp. n. (Plate XXII. fig. 11.) 

 R. testa suhperforata, pen j radii, nitida, solida, albescente ; anfrac- 

 tibtts 121, quorum 3| apicales, mamillati, parvi, vitrei, ceteris 

 nitentibus. hcrissimis, longitudinaliter recticostatis, costis lm<ibus, 

 ad guturas impressis, tumidulis, ultimo anfractu infra medium 

 costis evanidis, deinde ad basim spiraliter sex vet septem lirato ; 

 apertnra rotundo-ovata ; labro incrassato, ad basim paullum 

 effuso ; columella simplice, nitida. 

 Long. 9*50, lat. 2 mm. 



Hab. Gulf of Oman, lat. 24^ 05' X., long. 57° 35' E. 205 

 fathoms. 



One of the most interesting of the abyssal species dredged at 

 over the 100-fathoms line. It is quite unlike any Rissoid known 

 to us, and there is nothing approaching it in the National Collec- 

 tion, or depicted in any monograph of the family. Prom the 

 figure of B. neviUana Weink., from Hongkong, a rapprochement 

 is. we fancy, discernible, and for the present, at all events, would 

 place it among the Eurissoince, near that species. 



It is a solid, shining, smooth, hardly perforate, attenuately slender, 

 whitish cinereous shell, with very faint, almost imperceptible 

 ochreous tinge below the sutures ; the 3| apical whorls are small, 

 shining, vitreous, the next rapidly increasing proportionately in 

 size, and then with but gradual increase to the body-whorl. All 

 these whorls are longitudinally smoothly costatr, the 10 ribs of 

 th<- body-whorl vanishing below the middle, which is thence to the 

 base six or seven times spirally Urate. The mouth is oval ; outer 

 lip thickened, only slightly effuse towards the base ; columella 

 simple, white. 



ki—"j\\ (Bissoijna) distans Anton ( = canaliculata .Sclav.). 



1. Bombay (Ai» rcrombie). 



Rissoina (Bissolin \ ) i' w ii vsiuM \ Melv. 



P.G. Bushixe. 



1. Karachi Bombay (Ab«rcrornbie). 

 The few nl)~. eighl on the body-whorl, and smooth interstices 



