PARTULA, RAIATEA AND TAHAA. 229 



former direction 'has slightly overlapped the southern range of 

 P. thalia, and hybrids between the two species are quite com- 

 mon. To the southward it ranges about one mile, where it 

 extends a short distance up a valley which is the home of 

 P. citrina." (Garrett) . 



Partula garrettii PEASE, Proc. Zool. Soc., 1864, p. 672; 

 1871, p. 473. PPEIFFER, Man. Hel., vi, p. 158. SCHMELTZ, 

 Cat. Mus. Godeff., v, p. 207. HARTMAN, Cat. Part., p. 10; 

 Obs. Gen. Part., Bull. Mus. Comp. Zool., ix, p. 182. GARRETT, 

 Journ. A. N. S. P., ix, 1884, p. 56, pi. 3, f. 48. Partula 

 gonocheila SCHMELTZ (not of Pfeiffer), Cat. Mus. Godeff., 

 v, p. 92. 



Differs from the related P. thalia and P. nistica by its 

 less inflated form, extremely narrow or closed umbilicus, less 

 expanded lip and strongly developed columellar sinuosity. 

 Garrett remarks that "Its principal characters are its small 

 size, contracted aperture, rounded or angulated peristome 

 and nodulous columella, which latter is, as it were, pushed in 

 towards the aperture. The parietal region is very rarely 

 toothed. It is whitish or pale yellowish horn-color, rarely 

 fulvous or light brown, and sometimes the apex is purple- 

 brown. A variety with a brown base and sutural band is not 

 infrequent." 



Fig. 15 represents one of Pease's original lot. Fig. 19 

 is somewhat intermediate between garretti and rustica. It 

 has the columella and almost closed umbilicus of garretti, but 

 a somewhat fuller shape and a minute parietal tooth. 



31. P. UMBILICATA Pease. PI. 21, figs. 11, 12, 13, 14. 



The shell is globoscly ovate, solid, rather dull openly um- 

 bilicate, roundly angulate at the umbilicus, very delicately 

 striated spirally. Whorls 4!/o, convex, the last swollen. 

 Aperture rounded-oval, toothed. Lip internally thickened, 

 obliquely flat. The columella has a somewhat tooth-like cal- 

 lus, and is angular at the base. Color, yellowish or brown- 

 ish horn-color, faintly streaked with darker, the apex gener- 

 ally reddish-brown or dark purple ; seldom wholly dark chest- 



