- 427 - 



bus circa 18 exarata, mediana laevis, postica costellis radianti' 

 bus densissimis subundulatis sculpta. — Long. 12 Mm. 



Modiola discors Gould luv Mass. p. 130 F. 80, nec L. 



Mytilus conugatus Stiujpson New Englaud p. l2. — (Mod ) iTOuld 

 et Binney p 193, F. 491. Sars Norv. p. 30 T. 19, F. 2. 



Hab. oceanum arcticum. 



7. Modiolaria cuneata Jeffreys. T. transversa, 

 tenuicula, subhyalina, epidermide tenerrima aureo-Iutescente 

 induta, extus subcarinata, (carina ab apice ad rostrum decur- 

 rente), antice et transversim striata, postice striis radiantibus, 

 prope marginem dorsalem validioribus eleganter decussata; 

 apicibus minutis subterniinalibus ; latere antico arcuato ; margine 

 ventrali subhorizontali ; latere postico acute rostrato; pagina 

 interna valvarum pulchre inargaritacea, striata; margine dorsali 

 crenato — Long. 13, lat. 6 Mm. Fischer. 



Modiolaria cnneata Jeffreys Aun. Mag. (5) VI p. 315. ~ Fiscber 

 J. C. XXX p. 53. Locard Cat p. 496. 

 Hab. in abyssis sinus biscayensis. 



8. 'PModioIaria subclavata Libassi. T. ovata, antice 

 rotundata, postice declivis, marginibus dorsi et ventri subparal- 

 lelis; carina obtusa ab umbonibus porrectis utrinque decurrente 

 notata, antice granulato-striata, epidermide corneapostice pilosa 

 induta. — Long. 6 Mm. Reeve. 



Modiola subclavata Libassi Atti Pan. III 1859 p. 13 F. 7. — Jeff- 

 reys Pr. Z. S. 1879 p 568. — Locard Cat. p. 496. 



Lithodonuis semigranatns Reeve Conch. ic. sp. 28a. 

 Hab. mare lusitanicum usque ad Britanniam. 



4. Genus Orenella Brown. 



T. ovata vel rhomboidea, cancellata vel decussata, umbo- 

 nibus anticis, rectis; ligamentum parvum; cardo intus utrinque 

 dente crenulato munitus, linea cardinali crenulata. 



1. Crenella decussata Montagu. T. minuta, tumi- 

 dissima, oblique ovata, antice brevior, marginibus undique ar- 

 cuatis, umbonibus tumidis et prominentibus margini antico 

 incumbentibus ; epidermis llavescenti-fusca, nitida; striis tenuis- 

 simis elevatis radiantibus et concentricis subtiliter decussata; 

 linea cardinalis brevis, leviter crenulata. — Long. 5-6 Mm. 



Mytilus decussatus Montagu Test. Br. Suppl. p. 69. — (Cr ) Forbes 

 et Hanley II p. 2l0 T. 14, F. 2. — Jetfreys Br. Conch. II p. 133 

 T. 28, F. 6. — Sars Norv. p 31 T. 3, F. 4. — Nec de Kay. 



Modiola cicercula Moller Ind. p. 19. 

 Hab. mare arcticum et atlanticum boreale. 



2. Crenella rhombea Berkeley. T. oblique rhoin- 

 boidea, gibbosa, solidula, leviter iridescens, costellis radiantibus 

 60-70 lirisque concentricis 12—15 sculpta, sub epidermide 

 enui decidua lutescente margaritaceo-alba; margo anterior ob- 



