TASMANIAN LAND SHELLS. 33 



it is in great abundance on the rocks around the " Nut," gregarious 

 under entangled masses of plants in company with H. ccesus, If. Weldii, 

 and H. pictilis. So plentiful is it that thousands can be literally scraj)ed 

 together from the surface of a single block of rock, on lifting the 

 accumulated mass of plants and leaves. I have not seen any other 

 species in such great numbers as the present and its companion IT. 

 ccesus. There is a New Zealand shell having some resemblance to it, 

 but quite specifically distinct. The nearest Australian that I am 

 acquainted with is Jl. Murrayana, but that species differs in ^several 

 respects. 



Around Launceston and Hobart Town it is smaller and more 

 sparingly met with, although it is anything but rare. In this species 

 the embryonal whorls are striated as the rest of the shell, not smooth as 

 in H. MacDonaldi. i 



50. — Helix ( * ) mimosa. N. Sp. 



Shell small, discoid, openly umbilicated, reddish-brown, irregularly 

 rayed and blotched with pure white, which markings are more conspicuous 

 above than below ; regularly, closely striated throughout with slightly 

 waved, thread-like striae ; spire flat ; suture impressed ; whorls 4J, 

 convex, apical, smooth, the last narrow, rounded, not descending, below 

 striated as above and descending into, the deep, oj)en, perspective 

 umbilicus ; aperture lunate ; margins approximating ; columellar margin 

 neither dilated nor reflected. 



Diameter, greatest 2, least If; height, 1 mil. 



Habitat. — First Basin, near Launceston, among mosses on the 

 branches and trunks of trees j Chudleigh, Gad's Hill. 



A prettily marked flat species of very constant and distinct 

 character. In form it resembles H. Belli (Cox) from New South Wales, 

 but the colouration separates it from that, and in fact all its congeners. 

 It is very rare, and requires careful looking for among the thick 

 mosses. 



51. — Helix ( ) Petterdi — Brazier. 



Legrand, Col. for Mon. , species 67. 

 Pro. Zool. See, 1872. 



H. Agnewi — Cox. 



Legrand, Col. for Mon., sp. 27, pi. i., fig. 8. 



Shell widely umbilicated, depressly-circular, thin, dull brown, very 

 Tninutely striated throughout with lines of growth, having a silky 

 appearance ; spire moderately elevated ; suture very much impressed ; 



p 



