STENOTHYRA. 79 



Alt. 6-25, diam. 3 mm. 



Aperture : alt. 2*5, diam. 1*75 mm. 



Hob. Kyoukpong, River Irawady. 



Subfamily STENOTHYRINJE. 



Foot simple; radula of Bithi/nia ; operculum calcareous, spiral. 

 Distribution. S. and E. Asia; N. Australia (Recent): Eocene 

 of Europe (Fossil). 



Genus STENOTHYRA. 



Stenothyra, Benson, A. M. N. H. ser. 2, xvii, 1856, p. 496. 

 Nematura, Benson, J. A. S. B. v, 1836, p. 781 (not of Fischer, 

 genus Orthopt., 1813). 



TYPE, S. delta, Benson ; Gangetic Delta. 



Range. S. & E. Asia ; N.E. Australia. 



Original description. Animal. Caput tentaculis duobus setaceis 

 oculis postice prope bases tentaculorum sessilibus ; proboscide 

 eloDgata, cylindracea, extensili. Pes ovato-oblongus, medio ventri- 

 cosus, postice augustatus, acuminatus, processu brevi filiformi 

 subito desinens ; antice expansus, medio prof unde emarginatus ; 

 ala utroque latere porrecta late angustata, acuminata. 



Testa ovata, ventricosa, a latere cornpressa, ultimo anfractu 

 iusuper aperturam angulato, deflexo. Apertura integra constricta, 

 orbiculari, supra vix angulata ; peritremate acuto leviter intus 

 incrassato. Operculo teuui in spiram plenam convolute. 



158. Stenothyra deltae (Benson). 



Stenothyra delta (Benson), J. A. S. B. v, 1836, p. 781 (as 

 Nematura) ; A. M. N. H. ser. 2, xvii, 1856, p. 499 ; Sowerby, 

 Mag. Nat. Hist. (Charles worth's series) i, 1837 (as Nematura) ; 

 H. & T., C. I. pi. 37, fig. 2. 



Original description : Testa ovato-conica, a lateribus tumida, 

 lutescente, ultimo anfractu ventricoso, majori omnibus oblique 

 minute striatis; spira brevi, apice acuto; umbilico evanescente. 



Air. 6 mm. 



JIab. Ganges Delta. 



Subvar. minor, Nevill, Hand List, pt. 2, p. 43. 



Alt. 4, diam. 2-5 mm. 



Hob. Port Canning (Nevill, Wood-Mason). 



Subvar. minima, Nevill, torn. cit. 



Alt. 2-75, diam. 1-75 mm. 



Hab. Port Canning (Nevill, Wood- Mason). 



