Pacific coast species. 119 



An Oregonian Regiou species, ranging from 46<5 to 40^ latitude. It 

 also lias crossed the Cascade Mountains, ranging south- fig. 86. 

 easterly into the Central Province as far as the Coeur 

 d'Alene Mountains and Salmon River, Idaho. At the 



... , -, - M. devius, var. 



latter localities it is smaller and much less globose, and Mtaiani. 

 has its aperture decidedl}^ tridentate. This form is figured here. It 

 was also described by Mr. Bland as H. Midlani, his tyi)e beiug more 

 globose. I am convinced of the identify of the two forms, but repeat 

 his description and his figures : 



Helix Miillani, Bland. — Shell -witli umbilicus partially covered, globose-depressefl, 

 dark horu-colored, irregularly striated, having a thin epiderniis with inicro- 

 8Coi>ic spiral lines, and tubercles (the latter with hairs?) ; be- 

 neath the epiderniis shining; spire short; whorls 5| to 6, con- 

 vex, the last gibbous above, scarcely descending, the base rather 

 smooth, much constricted at the aperture; aperture subtriangular, 

 oblique, with a short, white, liuguiform, parietal tooth ; peristome 

 white or reddish horu-colored, thickened, expanded, and roundly 

 reflected, with 2 teeth on the margin of the callus, the lower oue 

 lamelliform, the other small, often obsolete, the columelhir mar- 

 gin partially covering the middle-sized, pervious umbilicus. 

 Greater diameter 13J, lesser 11°""; height, 7™"'. 



Jaw (of the Salmon River form) as usual in the genus, with 7 stout 

 ribs. 



The lingual membrane of the same (Terr. Moll., V, Plate VIII, Fig. 

 O) has 23-1-23 teeth, with IG perfect laterals. 



The typical form has tjie same type of dentition as the Salmon River 

 variety. It is figured in Terr. Moll., V, Plate XVI, Fig. S. ^.^^ 



There are 28-1-28 teeth. The thirteenth lateral has its 

 inner cutting cusp split. The jaw has fourteen ribs. The 

 genital system has a small, globular genital bladder on a 

 long, stout duct, which tapers greatly towards the bladder. 

 The penis sac is stout, long, cylindrical, with both vas defer- 

 ens and the retractor muscle entering its apex ; the ovarv is ^'^^ 



' "1/. devius, var. 



long and narrow. There are no accessory organs. (See ^uHani. 

 Bull. Mus. Comp. Zool., V, Fo. 10 Plate X, Fig. G.) 



Some forms of this species were formerly confounded by me with 

 Triodopsis Harfordiana. Such are here figured (Fig. 88). It is from 

 Salmon River. 



The variations of this species show very markedly the unsatisfactory 

 character of our so-called genera. Here we have the typical devius as 

 a Mesodon, though the variety is a true Triodopsis. 



