Io6 MOELLENDOkKF : LAND SHELLS OP CAROLINE ISLANDS. 



Diam. 1 6, alt. 9 "5 mm. 

 ,, 16, ,, io"5 mm. 



Diam. 1475, alt. 9"5 mm. 

 ,, 1 5 '5' >> 10 mm. 

 ,, 157, ,, II mm. 



Helix alia, Pease, Am. Journ. Conch., 1868, iv, p. 153, t. 12, f. i. — 

 Pfr., Mon. Hel., vii, p. 69. — 7V. a/fa, Pse., P.Z.S., 1871, 

 p. 474. — Tryon, Man. Conch., iii, p. 73, t. 14, f. 91. 

 Hah. — Ponape (Pease, Etscheid, Kubary). 



Pease's description and figure were evidently based on an imperfect 

 specimen, not fully grown. He gives the dimensions as io"9 mm., with 

 only 6 whorls, and does not describe the peristome. I received adult 

 examples in great numbers and have thought it advisable to publish 

 a new diagnosis. By the absence of perforation, the sigmoid shape 

 of the basal margin of the peristome, and the elevated conical spire, 

 somewhat resembles certain species o{ Dendrotroclius {Trorhonanina, 

 auctt.), but there can be no doubt that it belongs to the group of Tro- 

 cliomorpha kwsft'ri and must be referred to the same genus as that 

 species. Unfortunately I have not received living examples of either. 

 10.— Trochomorpha (Nigritella) nigritella (Pfr ). 

 T. modice sed pcrvie umbilicata, conoideo-depressa, solidiuscula, 

 plicato-striatula, et lineis spiralibus rugulosis microscopice decussata, 

 aut concolor atrofusca aut basi fusca, taenia angusta infra, altera 

 latione supra peripheriam flavesccntibus ornata. Spira conoidea 

 lateribus convexis, plus minusve elevata. Anfr. 6 convexiusculi, 

 sutura submarginata crenulata disjunct!, ultimus acute carinatus, basi 

 convexiusculus, ad umbilicum declivis. Apertura maxime obliqua, 

 securiformis, peristoma simplex, margine supero antrorsum arcuato, 

 valde deflexo, infero bene curvato, sublabiato, reflexo. 

 Diam. i4"5, alt. 8 mm. 



13 „ 8-5 mm. 

 Helix niijritella, Pfr., in Phil. Icon., ii, 9, p. 4, t. 6, f. 8 — Chemn., 

 ed. ii, Helix no. 602, t. 94, figs, i — 4. — Mon. Hel., i, p. 

 205. — Tr. nigritella, Pease, J. de Conchyl., 1870, xviii, p. 

 400. — P.Z.S., 1871, p. 457 (cum var. oppressa). — Tryon, 

 Man. Conch., iii, p. 78, t. 15, figs. 35—37- 

 Hah. — Ponape (Hochstetter, Pease, Etscheid, Kubary). 

 The variety oppressa, Pse., is merely one of the many individual 

 forms of this variable species. There are more or less elevated 

 variations both of the plain brown and of the banded forms. The 

 convexity of the base changes occasionally to flatness. 



10a.— Tpoehomoppha nigritella subsp. eontigua, Pease. 

 Spira plerumque magis elevata, anfr. 6 — 7 minus convexi, ultimus 

 basi planulatus aut subconcavus. 



