Mr. A. Adams on neio Species of Pelagic Mollusca. 403 



que increment! instructis ; suturis profundis ; apertnra ovata, an- 

 tics Tix producta ; labio rectiusculo, margine subreflexo ; labro 

 integro, regulariter arcuato. 



Hah. China Sea, off Formosa. 



In this species the whorls are more convex than in R. turrita, 

 V. d. Busch, which it most nearly resembles, and the straight, 

 elongate inner lip has the free margin somewhat reflexed ; the 

 aperture, moreover, is produced anteriorly, and the whorls are 

 transversely striated. The nucleus is small and pointed, and the 

 nucleolar whorls ai-e quite pellucid. 



The capture of this species was effected by my friend Lieut. 

 Bullock, of the ' Dove,^ Tender to the ' Actseon,' to whom I am 

 largely indebted for specimens and for the observation of parti- 

 cular localities. It may possibly be the same species as that 

 observed by Mr. Benson on his voyage to India, of which he 

 has made mention in his paper on lanthina in the ' Annals ;' 

 and to him, as a token of respect for his accuracy and enthusiasm, 

 I have dedicated it. 



Genus Ianthina, Bolten. 



lanthina [lodina) megastoma, A. Adams. 



I. testa helicophantoidea, turbinato-depressa, umbilicata, violacea, 

 superne pallida ; nucleo magno, obliquo, decumbente ; anfractibus 

 normalibus \\, rapide crescentibus, longitudinaliter sulcatis, ultimo 

 ample, ad peripheriam obtusim angulato ; apertura subtrigonali, 

 magna, patula, antice producta, subeffusa ; labio recto, antice vix 

 everso ; labro margine in medio excavato. 



Hab. Indian Ocean. 



This is a very beautiful but rather small species, not quite so 

 large as /. exigua, Lam., and resembling in form the genus 

 Helicophanta or Eurycratera. The nucleus is large, of two 

 whorls, and decumbent ; the shell is depressed and obtusely 

 carinate at the periphery, and the aperture wide, expandecl, 

 somewhat triangular and effuse anteriorly. Two adult and two 

 young specimens were obtained in the towing-net during our 

 passage across the Indian Ocean. It belongs to the subgenus 

 lodina of Morch. 



Genus Bellerophina, D'Orbigny. 



Bellerophina recens, A. Adams. 



B. testa parva, nautiliformi, globulosa, involuta, tenui, albida, roseo 

 tincta, umbilicata, subsymmetrica, concentrice crenato-sulcata ; 

 apertura angusta, transversa, semilunar! ; labro margine integro, 

 simplici. 



Hab. Indian Ocean. 



26* 



