HELIX-CHAROPA. 99 



transparent ; strongly plaited, plaits directed forwards on the upper 

 surface, and a little undulated, descending; about 30 in the tenth 

 of an inch (12 per mm.). The ribs are irregularly developed and 

 distant. Spire slightly elevated. Whorls 5 to 5t, narrowly rolled 

 up, very slowly increasing, rounded, the last very slightly descend- 

 ing. Suture not deep; aperture rotundly lunar, but little excava- 

 ted by the penultimate whorl, slightly oblique. Upper margin 

 advancing. Margins straight, convergent, acute ; columellar mar- 

 gin nearly vertically descending. The parietal wall inside a little 

 callous, white. Umbilicus broad, perspective, showing all the 

 whorls, about one-third of the diameter. 



Diam. 3, height 1*5 mill. (Suter.} 



Hastwell, Forty-mile Bush, North Island, New Zealand; under 

 rotten logs and dead leaves. Very scarce. 



This variety is distinguished from P. infecta by the slightly ele- 

 vated spire, the faint indistinct markings ; it is narrower ribbed, the 

 ribs being irregular in distance and development; there is one-half 

 to one whorl less, and the diameter of the shell is smaller. (Sut.~) 



Var. ALPESTRIS Suter. 



The shell of this variety differs from P. infecta Rv. by its different 

 color, it being cinereous-rufous with only a few pale-horny streaks. 

 The ribs are stouter and more distant, about 18 in the tenth of an 

 inch (7 per mill.). The whorls number only 4* to 5; they are 

 somewhat broader, less rounded, and the suture, in consequence, 

 less impressed. The peristome has no callosity inside. 



(Sut., Tr. N. Z. Inst. 1890, p. 88.) 



White Horse Hill, Hooker Valley, S. IsL, New Zealand. 



P. COLENSOI Suter. PI. 19, figs. 16, 17, 18. 



Shell discoidal, yellowish-grey, zigzag streaks of dark brown flow- 

 ing sometimes together, rather solid, transparent, faintly shining; 

 with strong plaits, directed forwards on the upper surface, slightly 

 undulating on the side ; the interstices striated with growth-lines. 

 Ribs about- 20 in the tenth of an inch (8 per mm.). Spire flat. 

 Whorls 5, narrow, slowly increasing, rounded, the last not descend- 

 ing, tapering. Suture deep. Aperture slightly oblique, rotundly 

 lunar little excavated by the penultimate whorl, margins convergent. 

 Umbilicus broad, perspective, showing all the whorls, about one-third 

 of the diameter. Diameter, 0'16 in. (4'25 mill.) ; height, 0*09 in. 

 (2-25 mill.) (Sut.) 



