4 Dr. P. V. Carpenter on new Forms of MuUushs 



r!ia2;onaliter parum producta ; margialbus subquadraiigulatiin ro« 

 tuudatis ; umbonibus proininenti'DUs, valde antice intortis ; tota 

 siiperficie iit in C. decussata scalpta, costulis crebris radiantibus 

 sequidistantibus, hie et illic aliis intercalatis ; lirulis concen- 

 tricis decassantibus : intus margine dorsa'i brevissimo, arcuato, 

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

 mina definiente, sito ; lamina cardinal! sub umbonibus intus por- 

 recta, dentibus validis instructa ; marginibus internis omnino cre- 

 natis ; cicatr. adduct. snbaequalibus, ventraliter sitis. Long, "l. 

 Lit. -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 Pinnseformis, extus prismatioa, intus subnacrea : ligamentura 

 sohdum : umbones extantes, terminales, intus concavi. 



10. Bryophila setosa. 



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

 ;iacreo, exquisite tincta : t. juniore planata, semirotundata, dor- 

 saliter recta, pequilaterali, conspicne 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 ejjidermide subspongiosa 

 vBstita, radiis setarum subdistantibus, marginibus eleganter ])ecti- 

 natis : intus ligamento solido dorsaliter producto ; limbo pallii 

 sequaliter prope margineu) decurrente ; cicatr. adduct. submediana, 

 inconspicua ; postice hiante ; antice propter byssum tenuem si- 

 nuata. Long. "13, lat. '2, alt. •! poll. 



Like a minute Pinna, or a transverse Margaritiphora without 

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

 Aviculids in being viviparous, like some other minute bivalves. 



IL ? Atys casta. 



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

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

 columella paulum intorta, efFusa ; umbilico antico minimo ; 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 1 20°) ; rufo-fusca, olivaceo 

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



* Bpiov, sea-moss J (piXos, loving. 



212 



