GASTEROPODA. 



the extremity ; anal siphon longer than in Dentalium, not 

 fissured. 



Distribution, 2 species. China ; Atlantic. 



Fossil, 7 species. Cretaceous-Miocene. Paris ; United States. 



Order II. — Pulmontfera.* 



Family I.— HELiciDiE.t 



Sophina, Benson, 1859. 



Type, S. schistostelis, Bens. 



Shell like Helix ; columella callous, with a basal slit. 



Distribution, 3 species. Moulmein. 



Cylindrella (p. 293). 



Animal -with no buccal plate; the lingual dentition varies 

 considerably in different species; in 0. scceva, Guild., the for- 

 mula is — ^-rr — ; the central plate is small, obtusely pointed, 



the laterals are uncinated, joined two by two, upper edge 

 fringed. 



" C. Goldfussi possesses 4 lamellae on the outer wall of the 

 whorls. The axis of C. turns and of some other Mexican spe- 

 cies is a highly polished tube, the young shells of which must 

 have a wide open umbilicus." — (Bland.) 



Macroceramtjs, Guilding. 



The genus has affinities with Bidimus, Pupa, and Cylindrella. 



Animal with an arcuate and striated buccal jDlate ; lingual 



dentition distinct from that of Cylindrella; in M. signatus, 



27 . 1 . 27 

 Guild. , = — ■ , the central plate is narrow, with an obtuse 



tooth, laterals with one prominent tooth sup- 

 porting two denticles and a small one at the 



Shell with the axis simple as in Bulimus ; 

 in M. amjilus a lamella revolves on the axis 

 within the lower whorls. Fig.i6. 



Distribution, 30 species. The genus belongs Central plate and 



. . laterals of 



to the "West Indian fauna, and has its greatest m. siynatus (Morse), 

 development in Cuba and Haiti. 



Achatina. — Sub-genus, Geostilbia, Crosse, 1867. 



Type, G. Caledonica, Crosse. New Caledonica. 

 * fcee p. 285. t See p. 288. 



41 



