I. t. “I. fenestratæ” indole simili, sed magis elongatâ, subnitente, pallide rosacea; vertice nucleoso decliviter immerso, celato; anfr. norm. postice subplanatis, suturis obtusis; costis tumentibus rotundatis circ. vii., suturas et umbilicum minorem versus obsoletis, plus minusve extantibus; interstitiis parvis, irregularibus, haud decussatis; peritremati continuo, labro tenui, secundum costas variantes undulato; labio medio calloso.
Long. 0·23, long. spir. 0·09, lat. 0·16, div. 60°.
Hab. S. Diego, 10 fm.; Sta. Barbara, 20 fm.; Cooper.
The fortunate discovery of some perfect young specimens displays a nucleus so like Odostomia that, despite the resemblance of the shell to Fossarus, which has a tuberoid nucleus, it most probably belongs to Pyramidellidæ.
Genus Rissoina, D’Orbigny.
Rissoina interfossa, Cpr. n. s. State Collection, No. 387, b.
R. t. satis magnâ, crassâ, albâ, satis turritâ, conspicue sculptâ; marginibus spiræ rectis, vertice mamillato; anfr. nucl. ?.. [detritis]; norm. vii. tumidis, angulatis, suturis angulatim impressis; carinis spiralibus validis, in spirâ ii.; alterâ posticâ interdum intercalante; anfr. ultimo duabus quoque peripherialibus, quintâ axim circumeunte; costis radiantibus validis, extantibus, circ. xiv., ad suturas contiguis, liris regularibus spiram ascendentibus, ad intersectiones carinarum nodulosis, ad peripheriam continuis; interstitiis quadratis, alte infossatis; aperturâ ovatâ.
Long. 0·26, long. spir. 0·18, lat. 0·10; div. 28°.
Hab. Catalina Is. 8-10 fm. 4; San Diego 1; Monterey, (var.) Cooper.