MOLLUSCA OF MICHIGAxN— WALKER, 



519 



ovate; columella more or less truncated; peristome blunt, 

 its margins joined by a callus. 



Animal heliciform, obtuse before, pointed l)ehind; 



mantle subcentral, thin, simple, protected by a shell; 



„. ,., , . , , anal and respiratory orifices on the ri^iht of the mantle 



Fig. lo4. Animal of , ,i • ^ ' r xi i n x- ■£; i i • i 



c. lubrica. (Biniiey.) Under the peristome 01 the shell; generative orince [)ehind 

 the right. eye-peduncle; no locomotive disk; no caudal mucus pore. 



Jaw low, slightly arcuate, wide, with but 

 little attenuated, blunt ends; cutting edge 

 -^^ - with a slightly produced, wide, median pro- 



■^^-^ ^^''^':j 3 jection; anterior surface without ribs, but with 



Fig. 155. Jaw of c. lubrica. (Binne.v) fine Vertical strisc. There is a strong muscular 

 attachment on its upper margin. 



Lingual membrane; centrals with basal plates small and narrow, expand- 

 ing at lower angles, tricuspid; laterals subrectangular, bicuspid, asymmet- 

 rical; marginals low. .wide and multidentate. 



Fig. 156. D:atitio.i of C. lubrica. fB-iiii, y.) 



COCHLICOPA LUBRICA (Muller). 



Shell imperforate, oblong-oval; smoky horn-color, smooth, and 

 shining; wiiorls 5-6; somewhat rounded, the last two-fifths of entire 

 length, rounded at base; apex obtuse; suture somewhat impressed; 

 aperture oval, longitudinal, peristome simple, thickened, often 

 slighth' rufus; columella obtuselv truncated at base. 

 Sfcfx'si Alt.'e.diam. 2imm. 



(Binney.) 



Muller, Verm. Hist., I., 104, (1774). 



W. G. Binnev, Man. Am. Land Shells, 194, fig. 202, 



(1885). 

 Miles, Rep. Geol. Surv. Mich., 236, (1861). 

 subcylindrace. Currier, Shell-bearing Moll. Mich., 6, (1865). 



subcylindracea, DeCamp, Shell-bearing Moll. Mich., 7, (1881). 



Ferussacia siihcylmdrica , Walker, Rev. Moll. Fauna Mich., 17, (1894). 



Helix lubrica, 



Ferussacia suhcylindrica, 



Achatina lubrica, 

 Zua 



Var. MORSEANA Doherty. 



Longer and more slender than the typical form. 

 Alt. 7, diam. 2 mm. 

 Cionella morseana, Doherty, Jour, of Con., I., 342, pi. IV., fig. 2, (1878). 



The typical form is generally distributed all over the state. The variety 

 has thus far been detected only in Ontonagon county. 



Family VALLONIID^. 



Jaw arcuate, lower margin with oi; without a median projection; lingual 

 membrane similar to that of the Pupillidce, central tooth narrower than the 



