NO. 1863. M0LLUSK8 OF THE GENUS ALVAXIA—BARTSCH. 343 



may be a pathologic expression due to the injury received. I am 

 unable to refer it positively to any of the known species and therefore 

 retain it m its present position. 



ALVANIA ALASKANA Dall. 



Plate 30, fig. 1. 



Alvania castaneaMoLh'ER, var-alaskanaBALh, Proc. U. S. Nat. Mus., vol. 9, 1886, 

 p. 307, pi. 4, fig. 9. 



Shell very elongate-ovate, white. Nuclear whorls one and one- 

 half, strongly rounded, very finely papillose. Post-nuclear whorls 

 strongly rounded, appressed at the summit, marked by fairly strong, 

 spiral cords, of which three occur upon the first whorl, so arranged 

 that the first below the summit marks the anterior termination of the 

 posterior third between the sutures; the other two divide the space 

 anterior to this into equal parts. The spaces separating these cords 

 are a little narrower than the cords. On the second whorl an addi- 

 tional cord makes its appearance halfway between the summit and the 

 first spiral cord on the preceding whorl, thus dividing the space be- 

 tween the sutures into five equal portions. The penultimate whorl 

 has the same spiral sculpture as its predecessor, but m addition tliis 

 whorl shows the peripheral spiral cord a little posterior to the suture. 

 In addition to these spiral cords, the whorls are marked by numerous 

 very fine, spiral striations, which are apparent on the cords and in the 

 grooves that separate them. The axial sculpture is reduced to very 

 feeble riblets, which are closely spaced and rather irregularly dis- 

 tributed. Suture very strongly constricted. Periphery of the last 

 whorl well rounded. Base rather short, umbilicated, marked by 

 six low, rounded, spiral cords which are situated on the posterior two- 

 thirds of the base and numerous fine, closely spaced, spiral striations. 

 Aperture subcircular; poterior angle obtuse; outer lip thin, showing 

 the external sculpture within; inner lip slender, curved, reflected, but 

 free from the base; parietal wall covered with a thick callus which 

 renders the peritreme complete. 



Cat. No. 213686, U.S.N.M., contains the two cotypes collected by 

 Doctor Dall at Nunivak Island, Alaska. One of these has 3^ post- 

 nuclear whorls and measures: Length 2.9 mm., diameter 1.5 mm., 

 the other has the same number of post-nuclear turns but has lost the 

 nucleus and measures: Length 2.8 mm., diameter 1.5 mm. I have 

 figured the last specimen. 



ALVANIA MONTEREYENSIS, new species. 



Plate 30, fig. 2. 



Shell elongate-conic, yello^\^sh white. Nuclear whorls IJ, well 

 rounded, marked by about 8 very slender, spiral lirations, of wliich 

 the 3 near the summit are weaker than the rest. Post-nuclear whorls 



