58 NEW SJ'ECIE.s OF TASMANIA^ MOLLUSCA, ETC. 



Marginella obesula, sp. nov. 

 Shell very small, broadly ovate, translucent white, 

 with a distinct, but blunt spire of two whorls. Aperture 

 narrow above, but widening rapidly towards the rounded 

 front. Columella convex ; the first plait, which is a 

 continuation of the front of the shell, is large, strong, 

 and curved. The next above is much smaller and rather 

 close to the first, above are four minute plaits, which reach 

 quite two-thirds up the columella. Outer lip thickened, 

 incurved in the middle, where it is armed with about 

 nine minute teeth. 



Length, 2; breadth, 1.4 mill. 



Types, with six others, from Frederick Henry Bay, 

 one other from Port Arthur. AVhilst this resembles such 

 relatives as M. s]ii)r(^!i(niii , Prit. and Gat., it nevertheless has 

 some good points of difference, and these are emphasised 

 by the ver}^ peculiar animal, which, showing through the 

 translucent shell, exhibits a bright orange colour, curiously 

 netted with white lines, each bordered with black, empty 

 shells show no traces of this peculiar ornamentation, which 

 must belong to the animal. In our other small species 

 the animal usuallv appears black or hornv. 



The habitat is also peculiar. Most of the speci- 

 mens have been taken from roots of the giant kelp, show- 

 ing it to inhabit rocky bottoms. 



PI. XIV., fig. 5. 



Marginella rixgens, sp. nov. 



Shell very simall, broadly pyriform, pure white, semi- 

 transparent, with an exsert, but very small spire of two 

 whorls, which has a tilt towards the right. Aperture 

 broad, esjiecially towards the rounded front. Outer lip 

 solid, shouldered, and much curved above, but straight on 

 its inner side, where it bears about six small denticles rather 

 irregular in size and spacing. Columella convex, but rather 

 straight in its middle part, and carries about six plaits, 

 of Avhich the first i?i a long, u]>ward 5weep from the base; 

 the next two are well developed, those above being much 

 smaller. 



Length, L8 ; breadth, 1.2. 



Type from Kelso, Taniar Heads, collected by the late 

 Aug. Simson ; another exactly similar from the Petterd col- 

 lection, probably from the same locality ; and eight others 

 from 40 fathoms off Thouin Bay, which differ slightly in 

 having more minute denticles on the lip, but are other- 

 wise the same. 



