235 



Hyal^ea inermis. T. ovato-globosa, postice angustata, com- 

 pressa et truncata, angulis posticis emarginatis, antice rotundata : 

 apertura augusta, transversa, labro haud porrecto. Animal alis 

 transversis angustis ad anguluin posticum emarginatis instruction. 

 Long. | ; lat. % : alt. f poll. 



From a figure by Mr. Dana ; locality not mentioned. 



Hyal^ea femorata. T. sub-cordata ; augulis posticis productis, 

 arcuatis et cornua subrecta, prrelonga, retroversa gerentibus. Animal 

 alis transversis trapezoidalibus munitum. Length of shell and animal, 

 also of alar expansion, lj inch. 



Obtained in the equatorial Atlantic. 



Described from a figure by Mr. Dana. It is remarkable for its 

 long and corpulent appendages. 



Cleodora exacuta. T. pellucida, triangularis, subtus concava, 

 supra per-convexa, antice rotundata, postice valde acuminata, lateri- 

 bus concaviter arcuatis. Animal cervice longo et alis divergentibus 

 oblongo-ovalibus instructum. Long. 1 poll. ; lat. f longitudinis. Found 

 by Mr. Dana, in lat. 44° N., long. 154° W., off the mouth of Columbia 

 River. 



Resembles a West India species which has the sides more deeply 

 concave, and the lateral angles prolonged into spines. 



Cleodora [Creseis] munda. T. elongato conica, modice recurva, 

 subcompressa, ad apicem rosacea : apertura rotundato-elliptica. Ani- 

 mal alis fere transversis late coadunatis, oblique triangularibus, sub- 

 arcuatis, instructum. Long. % poll. Found in the equatorial 

 Atlantic, and figured by Mr. Dana. 



Possibly C. virgula Rang. 



Cleodora [Creseis] placid a. T. elongato-conica, vix reflexa : 

 apertura circularis. Animal alis oblongis obliquis, angustis, Curtis, 

 instructum. Long. | poll. ; apertura? diam. ^ poll. Obtained in the 

 equatorial Atlantic, and figured by Mr. Dana. 



More obtusely conical than any described species, and the alar 

 expansions are small. 



Cleodora [Creseis] falcata. T. elongato-conica, valde re- 

 curva : apertura circularis. Animal alis flabellatis, obliquis, subar- 

 cuatis, iridescentibus munitum. Long. £ poll. Taken by Mr. Dana, 

 between Oregon and the East Indies. 



The extraordinary curve of the shell, as well as the peculiar form 

 of the wings, are the prominent characteristics. 



Atlanta primitia. T. nautiloidea, rotundato-ovata, compressa, 

 dextrorsum umbilieata, carina lata sensim angustata cincta : spira 

 anfr. 3 : apertura angusta, elliptica, angulis acutis ; labro arcuato 



