88 JOURNAL, BOMBAY NATURAL HISTORY SOCIETY, Vol. XVI. 



peripheriara et circa regionem umbilicarem laeviore, costulis ad basim fere 



evanidis ; apertura oblique ovali, intus alba, labro paullum incraesato. 

 Alt. 150, diam. 4 mm. 



Hab. Persian Gulf, near Fao. Likewise off Bunder Abbas, 5 fathoms, mud 

 bottom. 



A most exquisite species, beautifully cancellate and sculptured, though more 

 or less smooth below the periphery and around the narrow but deep umbilicus. 

 The whorls are all channelled at the sutures, this with a lens being very distinct 

 at the apex. 



The nearest ally is, perhaps, C. eburneum, Nevill (Journ. As. Soc. Bengal, xliv. 

 part 2, p. 101, pi. viii. figs. 21,22), which is, however, alarger shell, with coarser 

 sculpture proportionately. 



CYCLOSTREMA ANNELLARIUM*, sp, n. (PI. A. fig. 5.) 



C. testa parva, discoidali, profunde umbilicata, supra plana, alba, solidula ; 

 anfractibus tribus, quorum ultimus magnopere aliis exsuperans, rotundatus, 

 undique costi3 longitudinalibus circularibus, numero ad quinque et viginti, 

 praeditus, interstitiis pulchre striatis ; apertura rotundata, labro continuo, 

 crassiusculo. 

 Alt. 1, diam. 2mm. 

 Hab. Gulf of Oman, lat. 2-4° 58' N., long. 56° 54' E., 156 fathoms. 

 Exceedingly small, but well marked, being deeply umbilicate, flattened above, 

 three-whorled, the last whorl large, provided with about twenty-four rounded 

 longitudinal ribs. We know no species exactly comparable, C. conicum, Boog 

 Watson, being, perhaps, the nearest, from Pernambuco (' Challenger ' Ex- 

 pedition).; but this, as its name implies, is conical in form. The interstices 

 between the ribs are, as in C. conicum, beautifully spirally striate. 



CYCLOSTREMA PROMINULUM, sp. n. (PI. A. fig. 6.) 



C. testa depresso-discoidali, delicata, alba, minutissima, profunde umbilicata ; 

 anfractibus quatuor, quorum duo apicales perlaeves, subvitrei, caeteris duobus 

 spiraliter undique multiliratis ; liris laevibus, simul ac interstitiis, ultimo 

 permagno, ad peripheriam acuticarinato ; carina prorainente, deinde ad 

 basim lateribus obliquis, basi tumidula ; apertura rotunda, labro tenui. 



Alt. 1, diam. 2 mm. 

 Hab. Gulf of Oman, lat. 24° 58' N., long. 56° 54' E., 156 fathoms. 

 A very minute species, deeply umbilicate, white, with the surface uniformly 



multilirate, the lira at the periphery being metamorphosed into a strong, very 



prominent, and acute keel. 



CYCLOSTREMA EUCHILOPTERON f, sp. n. (PI. A. fig. 7.) 



C. testa parva, profunde umbilicata, albo-lactea, subpellucida, tenui, nitidi- 

 uscula, discoidali ; anfractibus quatuor, apicali vitreo, laevi, omnibus, prajter 



* Anncllus, a smallerine. 

 •j-su, x £,Xof » "fipov, from the winged process iu connexion with the lip. 



