OP CONCHOLOGY. 



285 



Shell cap-shaped, much elevated, thick, white, transversely 

 finely ribbed, longitudinally striate ; spire obliquely convolute, 

 free, detached. 



Neritina dispar. Pease. Plate 24, fig. 3. 



Description. — T. globosa, solida, laevigata, nitida ; anfr. su- 

 perne concavis, longitudinaliter, tenuiter et irregulariter striata ; 

 area columellari plana, callosa ; spira vix exserta ; nigra, punc- 

 tis albis angulatis maculata, interdum in seriebus ordinatis, aut 

 rubris fasciata ; aut lineis nigris longitudinalibus, flexuosis no- 

 tata ; columella aperturaque luteo-olivacea. 



Locality. — Insl. Roratonga. 



Shell globose, solid, smooth, shining, whorls concave around 

 the upper part, very finely and irregularly striate longitudinally ; 

 columella area flat and callous ; spire rather exserted ; black, 

 freckled with small angular white dots, sometimes disposed in 

 bands, seldom banded with pink, sometimes marked with fine 

 longitudinal wrinkled black lines ; columella and aperture yellow- 

 ish-olive. 



This species is allied to Oualanensis and lentiginosa. It is 

 smaller than either. From the first it may be distinguished by 

 the spire being exserted and concave beneath, and painted with 

 a smaller pattern. It difi'ers from the last principally in shape, 

 and also color of the aperture. 



Neritina rudis, Pease. Plate 24, fig. 4. 



Description. — T. ovata, crassa, solida, spiraliter confertim 

 striata ; spira depressa ; area columellari laevigata, plana, vix 

 concava, medio denticulata ; labro intus polita ; nigra, alboque 

 fasciata aut maculata, apertura lutescente. 



Dimensions. — Diam. 12, alt. 9 mill. 



Locality. — Ponape. 



Shell ovate, thick, solid ; spire depressed, spirally rather 

 closely striate ; columella area smooth, flat, slightly concave, 

 denticulate on the middle ; outer lip smooth, polished within ; 

 banded or spotted with black and white, aperture pale yellow. 



The above agrees in size and shape with N. pica (Gld., non 

 Chenu). 



Neritina rubida, Pease. Plate 24, fig. 5. 



Description. — T. ovata, rotundato-convexa, tenuiscula, striis 

 incrementis rugulosa ; spira depressa ; area columellari, cinerea, 



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