TASMANIAN LAND SHELLS. 



9. — Helix ( ) Hamiltoni — Cox. 



Cox, Pro. Zool. Soc, 1867. 



Mon., 1868, p. 32, pi. vii., fig. 2-2a. 



Legrand, Col. for Mon., sp. 4. 



Shell iimbilicated, sub-discoid, convexly depressed, thin, very closely 

 and sub-arcuately ribbed, interstices with extremely fine thread-like 

 lines, crossed by extremely minnte spiral ones, giving the shell, under 

 the lens, a linearly granular appearance, not shining, pale reddish horny ; 

 spire small, scarcely projecting, sometimes flat, suture impressed ; 

 whorls 5, rapidly increasing, flatly convex, last somewhat inflated, 

 roundly convex, not descending in front, moderately flattened at the 

 mouth above ; base with the striae smaller ; umbilicus perspective, 

 nearly equalling one-fifth of the diameter ; aperture diagonal, lunately- 

 oval ; peristome simple, thin, straight, margins approaching ; columellar 

 margin above moderately dilated and reflected. 



Diameter, greatest 0*70, least 0*50 ; height 0-20 of an inch. 



Habitat. — Macquarie Harbor, Port Davey, Black Kiver, Circular 

 Head, on the ground in moist places, among accumulations 

 of decaying herbage, and under fallen trees. 



Specimens from the last-mentioned locality are much larger than 

 those from either Port Davey or Macquarie Harbour, the margin of the 

 aperture is also a little expanded. I have but little doubt but that it 

 will be eventually shown that the present form with H. StepJiensi^ H. 

 plexus, H. Langleyana, H. Kingi, H. Du Cani, and H. Savesi are but 

 variations of one generally distributed form reaching a degree of develop- 

 ment according to the influence of local circumstances, and that the 

 differences are simply varietal and not specific. 



10. — Helix ( ) Stephensi — Cox, 



Legrand, Col. for Mon., species 6, pi. ii., fig. 6. 

 H. Pascoei — Brazier. 



H. Milligani — Brazier. 

 H. Floodi — Brazier. 



H. scrupulus — Cox. 

 H. coepta — Cox. 



Legi'and, Col. for Mon., species 65. 

 Pro. Zool. Soc, 1872. 



Legrand, Col. for Mon., species 69. 

 Pro. Zool. Soc, 1872. 



Legrand, Col. for Mon., species 70. 

 Pro. Zool. Soc, 1872. 



Legrand, Col. for Mon., species 76. 



Legrand, Col. for Mon., sp. 41, pi. ii., fig. 2, 



Shell with a deep, open, rather narrow, umbilicus ; depressly- 

 orbicular, thin, transparent, of a dull brown-yellow colour; spire scarcely 



c 



