ART. 20 ADDITIONAL MOLLUSKS FROM ECUADOK BARTSCH 7 



TURBONILLA (PYRGISCUS) TIA, new species 

 Plate 3, fig. 10 



Shell elongate-conic, pale straw-colored, with a broad light zone 

 at the summit and immediately anterior to the periphery, the space 

 between being a trifle darker, practically agreeing with the base in 

 coloration. The type has lost the nucleus and the early postnuclear 

 whorls. The first of the 7^/2 remaining turns has 20 slightly re- 

 tractively curved rather distantly spaced axial ribs. There are also 

 20 on the second and third, 22 upon the fourth, 24 upon the fifth 

 and sixth, and 36 upon the last. Upon this whorl they become rather 

 irregular in development and much more closely spaced than on the 

 earlier turns. On the early whorls the intercostal spaces, which are 

 rather strongly impressed, are about twice as wide as the ribs, while 

 on the last turn they are less than half the width of the ribs. The 

 intercostal spaces are crossed by spiral lines of pits which are of 

 rather irregular strength and spacing; the strongest pit is at the 

 periphery. There are 20 of these incised lines between the summit 

 and the periphery; they are a little closer crowded toward the 

 sui«mit than at the periphery. Suture moderately well impressed. 

 Periphery of the last whorl well rounded. Base moderately long, 

 well rounded, marked by feeble continuations of the axial ribs and 

 by 16 well-incised spiral lines. Aperture moderately large ; po.sterior 

 angle acute; outer lip thin, showing the external sculpture within; 

 inner lip slightly curved and strongly reflected and appressed to 

 the base for about half of its length, and provided with an obsolete 

 fold a little anterior to its insertion; parietal wall covered with a 

 thin callus. 



The type (Cat. No. 363074, U.S.N.M.) measures, length, 6.2 mm.; 

 diameter, 1.8 mm. 



Cat. No. 363075, U.S.N.M., contains another specimen. 



TURBONILLA (PYRGISCUS) INTIA, new species 



Plate 3, fig. 9 



Shell elongate-conic, early whorls bluish-white, the later ones 

 pale brownish-yellow, deepest on the base. The type consists of the 

 last six whorls, the nucleus and the early whorls being lost. These 

 whorls are almost appressed at the summit and rather high between 

 the summit and the periphery. They are marked by low broad 

 rounded retractively slanting axial ribs, of which 22 occur upon 

 the first to third of the remaining turns, 24 upon the fourth, 26 upon 

 the fifth and the last whorl. On the latter they become almost 

 obsolete. The intercostal spaces are narrow, less than half the 

 width of the axial ribs and but poorly impressed. They are crossed 



