Dall Diagnoses of New Species of MblZusks. 173 



(between the sutures) by from four to six spiral subequal threads, of which 

 those on the periphery are somewhat more prominent, and all are slightly 

 nodulous where they over-ride the riblets; on the base there are about 

 15 of these threads with somewhat wider interspaces; aperture rather 

 narrow, outer lip sharp, flexuous, the anal sulcus wide and shallow, half 

 way between the suture and the periphery; pillar lip smooth, canal 

 rather long, straight, and open. Length of shell, 10.5; of last whorl, 6.0; 

 max. liameter of shell, 3.0 mm. 



The sculpture of this shell recalls "Drillia" cancellata Carpenter of the 

 northern fauna, but this species is smaller, more slender and more deli 

 cately ornamented and there seems to be no operculum. The type is No. 

 109,303, U. S. National Museum. 



Mitra lowei sp. nov. 



Shell of a warm yellow-brown with a whitish apex; nucleus subtrochi- 

 form, smooth, solid, of about three conical whorls; subsequent whorls 

 (in the type specimen) about four, rapidly increasing in diameter; those 

 which immediately succeed the nucleus marginated in front of the 

 suture by two or three fine spiral grooves, the interspaces of which stand 

 up like threads, but these gradually become less pronounced and hardly 

 noticeable on the fourth whorl where the sculpture becomes on the peri 

 phery fine, very inconspicuous, and widely separated grooves, only 

 noticeable under a lens, but minutely punctate; they become somewhat 

 stronger on the base and canal; aperture rather wide and semi-lunate; 

 pillar with three nearly horizontal plaits; the canal very short and wide. 

 Length of shell, 5.5; of last whorl, 4.5; diameter 2.5 mm. 



This species is of the type of M. falgurita Reeve, but of markedly dif 

 ferent proportions, the nucleus is very distinct from that of the type of 

 M, barbadensiit. etc. The only specimen seen is clearly immature, but it 

 is not the young of any of the species known to inhabit the coast and is 

 sufficiently characteristic to be easily recognized. The type is No. 109,- 

 305, U. S. National Museum. 



Mitra dolorosa sp. nov. 



Shell smooth, slender, solid, acute; whorls six without the nucleus 

 (which has been lost); the apical whorls show a few (5-7) punctate spiral 

 grooves, which diminish with growth to two or one, and become obsolete 

 on the last whorl; the surface is covered with an olivaceous periostracum; 

 there is in front of the suture a broad ill-defined white band, which does 

 not reach to the periphery; the anterior part of the whorl is dark oliva 

 ceous brown; aperture long and wide, canal hardly differentiated, outer 

 lip thin, not lirate; inner lip smooth, with a mere glaze on the body, the 

 pillar solid, with three rather oblique plaits, diminishing forward, th 



