4 Dr. P. P. Carpenter on new Forms of Mollusks 



diagonaliter parum producta ; marginibus subquadrangulatim ro- 

 tundatis ; umbonibus prominentibus, valde antice intortis ; tota 

 superficie ut ia C. decussata sculpta, costulis crebris radiantibus 

 sequidistantibus, hie et illic aliis intercalatis ; lirulis concen- 

 tricis decussantibus : intus margine dorsali brevissimo, arcuato, 

 dentato ; ligamento curtissimo, in fossa omnino interna, celata, la- 

 mina definiente, sito ; lamina cardinali sub umbonibus intus por- 

 recta, dentibus validis instructa ; marginibus internis omnino cre- 

 natis ; cicatr. adduct. subsequalibus, ventraliter sitis. Long. *1, 

 Int. -12, alt. -09 poll. 



Located provisionally in Crenella from its likeness to C. de- 

 cussata, but with peculiarities of hinge and adductors which 

 approach Nuculina on one side and Cardilia on another. 



Genus BRYOPHILA*. 



Animal Aviculidseum, viviparum : inter algas, etc., habitans. 

 Testa Pinnaeformis, extus prismatica, intus subnacrea : ligamentura 

 solidum : umbones extantes, terminates, intus concavi. 



10. Bryophila setosa. 



B. testa parva, regulari ; cinerea, salmoneo sen chocolateo, intus sub- 

 jiacreo, exquisite tincta : t. juniore planata, semirotundata, dor- 

 saliter recta, eequilaterali, conspicue punctata : t. adolescente sub- 

 diaphana : t. adulta solidiore ; umbonibus rectis, terminalibus, 

 intus alte excavatis ; marg. dorsali breviore, recto ; antico recto ; 

 ventrali et postico late rotundatis : extus epidermide subspongiosa 

 v?stita, radiis setarum subdistantibus, marginibus eleganter pecti- 

 natis : intus ligamento solido dorsaliter producto ; limbo pallii 

 eequaliter prope marginem decurrente ; cicatr. adduct. subrnediana, 

 inconspicua ; postice hiante ; antice propter byssum tenuem si- 

 nuata. Long. -13, lat. '2, alt. '1 poll. 



Like a minute Pinna, or a transverse Maryaritiphora without 

 eary, or an Isognomon without pits. Differs from the other 

 Aviculids in being viviparous, like some other minute bivalves. 



11. tAtys casta. 



tA. testa elongata, tenui, subdiaphana, albida; antrorsum paulum 

 tumidiore ; spira celata, lacunata, (t. adultse) baud urnbilicata ; 

 columella paulum intorta, effusa ; umbilico antico minirno ; labro 

 postice producto, obtuse angulato ; tota superficie subtiiiter spira- 

 liter striatula. Long. *4, lat. -18 poll. 



On the confines of the genus, related to Cylichna. 



12. Ischnochiton parallelus. 



I. testa ovata, subelevata (ad angulum 120); rufo-fusca, olivaceo 

 tincta ; valvis latis, marginibus parum rotundatis, interstitiis par- 



* Epvov, sea-moss; <pi\os, loving. 



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