38 AUSTRALIAN LAX'D SHELLS. 



vex, obtuse, suture moderate, margined with a narrow reddish streak ; 

 whorls 5, slowly increasing, slightly convex, last roundly convex ; 

 aperture lunately-rounded ; peristome straight, thin, margins some- 

 what appi'oaching, columellar margin above dilated and reflected. 



Diameter, greatest O'OS ; least 57 ; hnght 0*30 of an inch. 



Habitat. Clarence River, about South Grafton (under bark and logs). 

 Mac Gillie ray. 



A thin horny semi-transparent .shell, like a starved miniature of H. 

 Grayi, and to be placed next to II. aridorum, a much more globose 

 shell, with a deeply impressed suture. The reddish streak along the 

 suture is not always present. 



98. Helix monacha. Pfr. Plate XVIII. Fig. 13, from Pro. 

 Zool. Soc. M.O. 

 Pfr., Pro. Zool. Soc., 1859, p. 25. Plate XLIII. Fig. 7. 



Shell imperforate, globosely-conical, solid, roughly striated and under 

 the lens, minutely granulated, of a chestnut colour ; spire conoidly 

 elevated, rather obtuse; whorls oj, moderately convex, gradually 

 increasing in size, the last slightly descending in front, obsoletepy 

 sub-angled in the middle ; aperture for the most part diagonal, 

 rotundately-lunar, livid within, shining ; peristome flesh coloured, 

 shortly expanded throughout ; margins separated, the columellar 

 margin being expanded at its insertion into a triangular adnate plate. 



Diameter, greatest 108 ; least 0"85 ; height 090 of an inch. 



Habitat. Ash Island, Hunter River ; also Mulgoa, near Penrith, and 

 at the Kurrajong, N.S.W. Cox. 



This species is not abundant, and is apt to be confounded with the 

 smaller specimens of II. coriaria, and the dark specimens of H. 

 Grayi. 



99. Helix MulgOSe. Cox. Plate I. Figs. 3, 7, 7 a. M.C. 



Shell with a deep almost covered umbilicus, thin, light, transparent, 

 horny, turbinately-globose, generally reddish-brown, Fig. 3, but 

 frequently pale olive-green, Fig. 7 ; whorls 6, the last much in- 

 flated, and obsoletely keeled, descending in front; obliquely, rather 

 roughly striated above the obsolete keel, smooth and shining below ; 

 aperture lunately-rounded, light purple within ; peristome very 

 slightly thickened ; lip a little everted, pale bluish- white ; margins 

 approaching, joined by a thin shining callosity; columella white, 

 dilated, almost covering the umbilicus. 



Diameter, greatest 1*05 ; least 0"90 ; height l'OO of an inch. 



Habitat. Mulgoa, near Penrith, N.S.W. Cox. 



At times, after rain, this species is very abundant, otherwise it is not 

 to be found except by digging deeply about the roots of shrubs 

 where it buries itself, and remains for months. There are two very 

 distinct varieties of it one of a reddish-brown colour, the other of a 

 pale olive-green. This species has for years given me much trouble 

 in determining several of the species of the Australian Land Shells ; 

 for a time I considered it as a variety of II. Grayi, but, although 

 extremely like varieties of that species, where no red blotch is found 



