from the Persian Gulf, &c. 143 



A very delicate pellucid Eulimo'id, as the specific name 

 chosen denotes. It indeed seems fatuous to be now com- 

 pelled to group the members of this genus of ivory whiteness 

 and delicacy under a name so ill-chosen, and suggestive of 

 Cimmerian darkness ! 



Mucronalia aethria*, sp. n. (PI. IV. fig. 10.) 



M. testa parva, perlsevi, diaphana, nitidissima, oblongo-fusiformi ; 

 anfractibus ad 12, quorum apicales 2 sirapliciter heterostrophi, 

 his 3 proxirais attenuato-caudatis, ceteris ad suturas vix im- 

 pressis, leniter accrescentibus, ultimo longitudine tres approxi 

 matos anfractus a3quante ; peristomate tenui, columella obliqua, 

 apertura ovato-oblonga. 



Long. 5, lat. 1*50 mm. 



Hab. Persian Gulf, Henjam Island, 40 fathoms, 1906. 



This Mucronalia is a plain, extremely smooth and shining 

 little species, hardly impressed suturally, the upper whorls 

 much narrowed and slightly caudate, while the nuclei are 

 heterostrophe. Three other species are found in these seas, 

 as follows : — 



M. bizonula, Melv. Proc. Malac. Soc. vii. 1906, p. 73, 

 pi. vii. fig. 8. — A minute twice-banded species, found in the 

 Gulf of Oman at 156 fathoms and since recorded by Mr. O. 

 lledley f from Mast Head Reef, Queensland, 17-20 fathoms. 



M. lepida, Melv. ibid. p. 72, pi. viii. fig. 31. — An ovate, 

 small form from the same locality. Entirely white and semi- 

 pellucent. 



M. o.vytenes, Melv. ibid. vi. 1904, p. 163, pi. x. fig. 13. — 

 Larger than the last in all its parts. Also from the Gulf of 

 Oman, dredged from deep water. 



Turbonilla exilispira \, sp. n. (PL IV. fig. 12.) 



T. testa alba, minuta, perattenuata, semipellucente ; anfractibus 13, 

 quorum 3 apicales, valide heterostrophi, cseteris angustis, ad 

 suturas impressis, arete oblique costulatis, costulis ad basin 

 evanidis, interstitiis hevibus, ultimo vix latiore ; peristomate 

 recto, tenui, apertura squarrosula, columella recta. 



Long. 4, lat. *75 mm. 



Hab. Karachi. 



Almost as narrow as T. anguatissima §, Melv., from the 



* alQpios, clear, bright. 



t Proc. Linn. Soc. N.S.W. 1907, vol. xxxii. p. 50o. 



j Exilxs, spira, with slender spire. 



§ Proc. Malac. Soc. vol. vi. 11)0), p. 55, pi. v. fig. 13. 



