312 Bulletin Vanderbilt Marine Mtiseum, Vol. VII 



coarsely nodose ; between these ridges there are finer, intermedi- 

 ate, spiral striae, also microscopic spiral lines. The aperture is 

 about one-half as long as the spire, a wide oval, abruptly acute- 

 angled at the upper and lower ends ; the canal is wide, deep, ter- 

 minating externally in a shallow notch, marginally thickened ; the 

 outer lip is semi-circular, sloping inward, widely fluted, margin- 

 ally crenulate, consisting of about fifteen narrowed areas alter- 

 nating with sixteen wider spaces, the narrowed groove-like areas 

 being chestnut brown ; the inner lip is porcellanous, thicker on the 

 outside of the canal; the pillar is broad, transversely furrowed 

 with numerous plaits which increase in strength, from lowermost 

 to uppermost, which is separated by a smooth space from the 

 upper angle of the aperture. The operculum is obliquely oblong- 

 ovate, thick, of horn-colour, with growth lines indicated by the 

 irregular imbrication of the deposit. 



References: Lister, M., Conch., t. 960, fig. 13. 

 Triton nodiferum, Lamarck, J. B., Anim. sans Vert., 1822, t. IX, 

 p. 178, No. 2. — Reeve, L., Conch. Icon. Triton No. 9, t. 3, f. 9. 



Triton nodiferiLs, Martini, F. H. W., und Chemnitz, J. H., Syst. 

 Conch. Cabinet, 1878, Moll Gastr. Purpuracea Bd. II, p. 177, 

 pi. 51. — Dautzenberg, p., et Fischer, H., Res. Campagnes 

 Sci. du Prince de Monaco, 1906, Fasc. XXXII, Mollusques, 

 p. 32. 



Class: PELECYPODA 



Order: FILTER ANCHIA 



Family: ARCIDAE 



Genus: ARC A Linne 



Subgenus: Navicula de Blainville 



Area (Navicula) avellana Lamarck 



i 



Plates 121 and 122 



Type : Lamarck's type of avellana came from the Islands of 

 Saint Peter and Saint Francis, on the south coast of Australia, 

 while his type of retzisa came from Timor. Both of these types 

 are deposited in the Paris Museum. 



