SOUTH AFRICAN MARINE MOLLUSKS. 43 



Family MITRIDAE. 



Genus MITRA Martyn. 



MITRA BATHYRAPHE Sowerby. 



Two, Cat. No. 186736, U.S.N.M., from Port Alfred (Coll. No. 95). 



MITRA CANALICULATA Sowerby. " 



Cat. No. 186734, U.S.N.M., three, from Port Alfred (Coll. No. 93). 

 Cat. No. 272158, U.S.N.M., two from Kowie, South Africa. 



MITRA CAPENSIS Dunker. 



Cat. No. 186733, U.S.N.M., five, from Port Alfred (Coll. No. 92). 

 Cat. No. 272159, U.S.N.M., two from Kowie, South Africa. 



MITRA HELENA, new species. 



Shell small, wax-yellow, with two bands of white, the first of which 

 occupies a little more than the anterior half between the sutures, 

 while the second one, which is about half as wide, occupies the mid- 

 dle of the base. Nuclear whorls decollated. Postnuclear whorls 

 shouldered at the summit, marked by very strong, slightly retractive, 

 axial ribs, of which 16 occur upon the first of the remaining turns, 20 

 on the second, and 16 upon the rest. In addition to the axial ribs, 

 the whorls are crossed by strong spiral cords, of which five occur 

 between the sutures of the first three and seven upon the fourth and 

 last. The spaces inclosed between the axial ribs and spiral cords are 

 deep pits on the posterior half and deep slits on the anterior half 

 between the sutures. Base rendered decidedly sigmoid on the left 

 side by the twisting of the anterior portion; marked by the continu- 

 ations of the axial ribs which extend to the tip of the columella, and 

 10 spiral cords, of which the 6 posterior to the columella are like 

 those on the spire, while the first 2 on the columella are broader and 

 stronger and more rounded, the last two on the anterior end weaker. 

 Suture well impressed. Aperture narrow, channeled anteriorly; 

 posterior angle acute; outer lip marked by 12, slender, spiral lira- 

 tions within; columella provided with four oblique folds, which de- 

 crease regularly in size from the posterior to the anterior; they also 

 become more oblique in the same order. 



The type and another specimen, Cat. No. 272156, U.S.N.M., come 

 from South Africa. The type has 6 whorls remaining and measures: 

 Length, 15 mm.; diameter, 6.6 mm. These specimens came to the 

 United States National Museum, labelled " Mitra daedala, Reeve,'' in 

 a donation by Mr. John B. Henderson, in a collection purchased from 

 Sowerby and Fulton. Mitra daedala of Reeve is a Philippine species, 

 which we have from the islands ; it is much larger than the present 

 species. 



