TRICHODINA. 189 



strongly colored, and while larger, it has one whorl less; the 

 columella is less arched, being almost straight. Some in- 

 dividuals, more slender than the types, are 33 mm. long, 11 

 wide (Morel.). 



Sa. Var. olivacea n. var. PL 57, figs. 25, 26. 



In the specimens before me the cuticle is decidedly oliva- 

 ceous or chestnut- green, the surface of the shell exposed by 

 its loss being white. It is glossy, faintly striate, the striae 

 slightly stronger below the suture; the terminal cone is more 

 strongly striate and the second and third whorls are crenu- 

 late below the suture (pi. 57, fig. 26). The last whorl has 

 no indication of an angle, or change of sculpture or color at 

 the periphery, such as occurs in many allied forms. The 

 aperture is oblique, the outer lip blunt, black-edged. The 

 columella is obliquely truncate, and there is a heavy colu- 

 mellar and parietal callous. The shell is thick, solid and 

 opaque. 



Length 31, diam. 10.6 mm. ; length of eperture 10.6 mm. 



Length 30, diam. 10.4 mm. ; length of aperture 11 mm. 



Great Comoro Island. 



9. T. CORNEA (Morelet). PI. 57, figs. 21, 22, 23. 



Shell imperforate, subfusiform-turrited, rather solid, deli- 

 cately striate, sometimes granulate; diaphanous, glossy, oily- 

 <corneous. Spire elongate, the apex rather acute, suture im- 

 pressed. Whorls 9, slightly 'convex, the last about one-third 

 the total length, tapering at the base. Aperture slightly 

 oblique, acutely semioval, milk-white inside; peristome sim- 

 ple, unexpanded, the columellar margin arcuate, obliquely 

 truncate. Length 28 to 32, diam. 9 mm. (Morel). 



Comoro Is.; Anjouan (Bewsher, type loc.) ; Great Comoro 

 (Humblot). 



Achatina cornea MOREL., Journ. de Conchyl. 1877, p. 335, 

 pi. 13, f . 9 ; 1885, p. 289. Homorus c., KOBELT, C. Cab. p. 95. 



The initial half whorl is smooth, raised, and forms the 

 rather acute apex ; then close, fine, regular and arcuate riblets 

 set in, continuing for about two whorls, where they become 



