— 230 — 



toma incrassatum, expansum atque reflexum, superne sinua- 

 lum, ad sinulum attenuatum, sub sinulum angulatum, deinde 

 bidentatum, dentibus recedentibus, superus minor, margo 

 dexlra dentem immersum prœbens, margo basalis bidcntata, 

 dens exterior major ; plica parietalis média valida, fîexuosa 

 et longe intrans. 



Color testse perpallide succineus. 



Altit. 5 mm. ; diam. major 40 mm., minor 7 mm. 



Var. minor 



Diam. major 6 mm., minor 4 mm.; ait. 3.5 mm. 

 Habitat : Phong-Tho (Col 1 Messager). 



Streptaxis d^edaleus nov. sp. 



Testamediocris.angusteperforata. Anfractus 6: embrgonales 

 duo Isecigati, sequentes costulali, costulis imprcssis ad partem 

 basalem anticam anfractus ultimi evanidis ; anfractus ulti- 

 mus antrorsum devians, deinde ad aperturam perpaulum 

 molliterque ascendens, post labrum triscrobiculatus. Aper- 

 tura trigonalis, angulo externo rotundato ; peristoma subcon- 

 tinuum, incrassatum et reflexum, superne sinulum rotun- 

 datum pauloque recedentem efformans. Labrum crassum 

 tridentatum : dens superus minor, sub angulo infero sinuii 

 positus, dens médius a marginc recedens, bifidalus, dens infe- 

 rior debilis, in angulo externo aperturœ profunde immersus, 

 subbifissus, margo basalis dente unico crasso munita ; plica 

 parietalis supera elevata, incrassata, peristomatem continuans 

 sinulum rotundatum circumdat ac deinde depressa in aper- 

 turam profunde intrans, annulum efpngit et antrorsum 

 elapsa, sub callum sinuii desinit. Umbilicus comœformis, 

 striatus, haud profunde perforatus. 



Colot sordide albus . 



Altit. 3, diam. major 6, min. 4 mm. 



