88 THE PROCEEDINGS OF THE LINNEAN SOCIETY 



ovate. But the width of the oval varies considerably. In the 

 three specimens selected from St. Leonards, near Launceston, 

 figs. 2 a, b, and c ; one (fig. 2 a,) is almost globose ; 2 b, is less 

 so, while 2 c, is lengthened oval, much more attenuated at the 

 apex than any other except fig. 5 b, a specimen from Both well.* 

 This globular habit is not due to age, for in fig. 6 a, we have a 

 full grown form from Ringarooma, which is even still more 

 globose and tumid. In fig. 4, a specimen from Macquarie 

 Harbor, t we have a globose form yet again differing from the 

 preceding, and with a very obtuse spire. I have placed three 

 shells side by side in the plate, namely fig. 3 a, 4, and 3 b, in 

 order to show the contrast of the variation in shape. Figs. 3 a, 

 and b, are from Port DaveyJ, and fig. 4, as already stated, from 

 Macquarie Harbor. In figs. 7 a, b, and c, we have other 

 specimens from Macquarie Harbor, which equally vary in size 

 and shape. I draw attention also to the form of the apex, which 

 is very obtuse in fig. 4, 6 a and b ; moderately so in 2 a and b, 

 3 a, 5 a, 7 b, and almost acute in 2 c, 7 c, 5 b. The form of 

 the aperture is equally varied ; in 2 a, 6 b, 7 a and b, and 4 it is 

 subquadrate, while in 5 b, it is narrowly pyriform, in 2 b, 3 a, 

 and 3 b, a little wider but of the same shape. In fig. 5 a, the 

 last whorl is produced so as to make the form oblique. The 

 columella is also extremely variable. In 2 a, it is very much bent, 

 contorted, and truncate, while the inner lip is reflected, giving 

 rise to a false umbilicus. This reflexion of the lip is seen also to 

 a smaller extent in fig. 2 b, but no trace of it remains in fig. 2 c, 

 where the pillar is twisted almost to a plait. In figs. 3 a and b, 

 from Port Davey, there is no perceptible reflexion of the columella. 

 When the animal is taken fresh out of the shell, the whole 

 of the aperture and part of the columella has a kind of silky 

 enamel, which is quite transparent, and allows the coloring of the 

 shell to be seen very clearly. But if the shell becomes dead, this 

 enamel alters to an opaque chalk white, and quite conceals the 

 color of the aperture, though it must be a lining of the most 



• About 50 miles north of Hobart, and St. Leonards is about 120 miles, 

 t Formerly a convict station on the west coast, but now uninhabited. 

 X On the extreme south west of the island, now only occupied by a few timber sawyers 

 and splitters. 



