8 PROCEEDINGS OF THE NATIONAL. MUSEUM Vol.70 



as far anterior to the periphery as it does upon the base. Nuclear 

 whorls decollated. Postnuclear whorls rather inflated, appressed at 

 the summit, slightly rounded near the summit and the periphery and 

 somewhat flattened in the middle, marked by very strong, slightly 

 protractively curved, rounded axial ribs, of which 16 occur upon the 

 first four of the remaining turns, and 18 upon the rest. The inter- 

 costal spaces, which are about as broad as the ribs, are deeply im- 

 pressed. In addition to the strong axial ribs, the whorls are marked 

 by fine incremental lines which are apparent in both intercostal 

 spaces and on the ribs ; they are also marked by rather strong, closely 

 spaced spiral striations. Suture strongly impressed, constricting the 

 whorls. Periphery angulated. Base short, slightly inflated, well 

 rounded, marked by the very feeble continuations of the axial ribs, 

 which evanesce shortly after passing the periphery, numerous lines 

 of growth, and closely spaced, strong spiral striations. Aperture 

 rather large, broadly oval, posterior angle obtuse; outer lip thin, 

 showing the external markings as well as the color bands within; 

 columella slender, slightly curved, and slightly reflected over the 

 base to which it is appressed for the posterior half of its length. 



The type. Cat. No. 362144, U.S.N.M., comes from Shuyak Strait, 

 Afognak Island, Alaska. It has six and one-half whorls, and meas- 

 ures, length, 6.3 mm. ; diameter, 2.4 mm. 



This species is nearest related to Turhonilla {Pyrgolatiipros) new- 

 comhei Dall and Bartsch, which is known from British Columbia and 

 Washington. It differs from the latter in being in every way more 

 robust and in having the whorls more inflated. 



TURBONILLA (PYRGOLAMPROS) MIDDENDORFFI, new species 



Plate 2, fig. 2 



Shell elongate-conic, flesh colored, excepting a broad band of 

 bright chestnut brown which extends over the periphery and con- 

 siderably anterior and posterior to this. Nuclear whorls two and one- 

 half, forming a depressed helicoid spire, the axis of which is almost 

 at right angles to that of the succeeding turns, in the first of which 

 the nuclear spire is about one-sixth immersed. Postnuclear whorls 

 rather high, appressed at the summit, marked by broad, low, rather 

 closely spaced, almost vertical axial ribs, which are very feebly ex- 

 pressed on the early turns. Of these ribs there are 18 on the third, 

 20 on the fourth and fifth, 22 on the sixth, and 24 on the last whorl. 

 The spaces separating the ribs are only about one-half as wide as 

 the ribs. In addition to the axial sculpture the whorls are marked 

 by numerous, closely spaced, spiral striations. Suture moderately 

 constricted. Periphery of the last whorl somewhat inflated. Base 

 moderately long, inflated, marked by the feeble continuations of 



