REPORT ON THE LAMELLIBRANCHIATA. 275 



Modiola, Lamarck. 

 Modiola barhata (Linnd). 



Mytilus harhatus, Linne, Syst. Nat., erl. 12, p. 1156. 



Blijtilas harhatus, Jeffreys, Brit. Conch., vol. ii. p. 114, vol. v. pi. xxvii. fip. 3. 



Mudiola barhata, Forbes and Hanley, Brit. ]\Ioll., vol. ii. p. 190, pi. xliv. fig. 4. 



Habitat. — Station 2;33a, Kobd, Japan, in 50 fathoms sand. 



The European Mytilus modiolus is ah'eady known as an inhabitant of Japane.se waters, 

 but this is, I believe, the first record of the occurrence of Modiola barhata, another well- 

 knowTi form on manj' parts of the coast of Europe. 



Modiola capax, as figured by Reeve, is very closely related to, if not identical with, 

 this species. 



Modiola glaberrima (Dunker). 



Volsella glaherrima, Dunker, Proc. Zool. See. Lond., 18.56, p. 363. 

 Modiola glaherrima, Reeve, Conch. Icon., vol. x. pi. viii. fig. 48. 

 Perna glaherrima, Angas, Proc. Zool. Soc. Lond., 1867, p. 929. 

 Modiola glaherrima. Smith, Report "Alert" MoUusca, p. 108. 



Habitat. — Port Jackson, Sydney, in G to 15 fathoms. 



This species has not, I believe, been recorded from any other locality than the Sydney 

 district. 



Modiola ivatsoni, n. sp. (PL XVI. figs. 5-5c). 



Testa fragilis, subpellucida, albida, marginem dorsalem versus inferneque viridi tincta, 

 polita, incrementi lineis striata, pone umbones subfortiter corrugata. Valvae in medio 

 convexae, postice conipressaj, latge, areuatas, autice angustatas. Margo dorsi posterior 

 leviter convexus, ventrali medio levissime incurvato. Umbones parvi, approximati, 

 iridescentes. Pagina interna alba, parum nitida. 



This species is very fragile, semitransparent, white, stained with pale olive-green 

 along the dorsal margin, and upon the lower portion of the valves. The valves ai-e 

 moderately convex at the centre and become compressed behind. They are very narrow 

 at the anterior end and sharply rounded, gradually widen posteriorly, and terminate in a 

 broadly arcuate end. The dorsal margin rises considerably behind, and is faintly convex, 

 the ventral, on the contrary, being feebly incurved. 



The sculpture consists of fine concentric lines of gi-owth, and excessively minute 

 radiating lines, not incised striae. In addition to this, the dorsal surface for some distance 

 behind the umbones exhibits several plications or wrinklings. The bealcs are small, 

 incurved, somewhat iridescent, situated at a short distance from the anterior extremity. 



