MELVILL : GASTROPODA FROM THE PERSIAN GTJLF, ETC. 163 



anfractum apud ultimuni circa 18, ultimo curto, compressulo, apertura 

 subrotunda, labro tenui. Long. 4, lat. 1 mm. 



A well-marked, but hardly common form. There are several other 

 species of this difficult genus and its immediate allies from the same 

 locality, many of which we have elected, at present, to consider forms 

 of such common Turhonillce as T. sororia, terebrina, or basilica, Melv. 

 It is indeed a thankless and almost hopeless task to thoroughly sort 

 out even, much less attempt to classify, a large gathering of such 

 a genus as this ; especially as the fact should not be lost sight of that 

 very probably there are sexual differences to be considered, affecting 

 both form and texture of shell. 



TURBONILLA RECTICOSTATA, n.Sp. PI. X, Fig. 12. 



T. testa eleganter fusiformi, gracili, alba, pai'um nitente, tenui, 

 anfractibus (inclusis apicalibus 2 reversis, globulosis, heterostrophis, 

 subvitreis) 11-12, apud suturas impressis, pauUura gradatulis, undique 

 longitudinaliter costatis, costis rectis, paullum incrassatis, interstitiis 

 omnino Isevibus, ad basim anfractus ultimi evanidis, numero circa 16, 

 apertura ovata, labro tenui, fere continuo, columella obscure plicata. 

 Long. 6, lat. 1-50 mm. 



I think this TurboniUa quite distinct from the larger and coarser 

 T. Candida, H. & A. Adams, which occurs in the Persian Gulf likewise. 

 The apical whorls are more conspicuously reversedly coils in T. recti- 

 costata, the whorls are more gradate, the ribs perfectly straight 

 throughout ; on the upper whorls of Candida they are closer and 

 suboblique, and likewise fewer in number. It is one of the less 

 frequent forms ; seven or eight examples alone have yet come to light. 



MlTCRONALIA OXYTENES,^ n.Sp. PL X, Fig. 13. 



M. testa oblonga, parva, albo-vitrea, nitidissima, polita, anfractibus 7, 

 quorum apicales 3, contract!, angusti, mucronati, semipellucentes, 

 ctBteris latioribus, cylindricis, infra, juxta suturas, spiraliter interne 

 pellucido-zonatis, apertura anguste ovata, labro simplice, tenui, colu- 

 mella obliqua. Long. 3'75, lat. 2 mm. 



The nearest approach I have seen to this species, of which but three 

 or four specimens alone have so far occurred in the above locality, is 

 M. cylindrica, Sowb.,^from Cebu, Philippines, a shell twice the length, 

 more pellucid, and with more arched and flexuose lip. 



Another Mucronalia has been noticed to occur with the foregoing, 

 but in too imperfect a condition to diagnose. 



MiTRA TowNSENDi, n.sp. PI. X, Fig. 14. 



M. testa oblongo- fusiformi, solida, laete castaneo -brunnea, anfrac- 

 tibus 8, quorum apicales duo, cseteris apud suturas paullum impressis, 

 fere rectis, undique spiraliter arete punctatis, punctis minutis, apertura 

 oblonga, intus nitida, brunneo-livescente, labro paullum effuso, colu- 

 mella albo-livida, 5 plicata. Long. 30, lat. 10 mm. 



' o|uTeVrjr, sharply drawn to a point, in allusion to the three apical whorls. 

 * Proc. Mai. Soc, vol. iv (1900), p. 127, pi. xi, fig. 6:. 



