HELIX-HADRA. 127 



H. semicastanea PER. Zeitschr. f. Mai. 1849, p. 77 ; Monographia iii, 

 p. 222 ; Conchylien Cabinet, t. 56, f. 3-5. REEVE, Conch. Icon., f. 

 1348. HEDLEY, Proc. Roy. Soc. Queensl. v, p. 61. Cox, Mouogr. 

 Austr. Land Shells, p. 56, t. 5, f. 10. H. bipartita var. DESHAYES. 

 H. fumculata PER. P. Z. S. 1854; Monogr. iv, p. 186. REEVE, 

 Conch. Icon., f. 1363. Cox, Monogr. Austr. L. Sh., p. 46, t. 11, f. 15. 



This extremely variable form is, as Dr. Cox says, unquestionably 

 a modified bipartita. A number of the leading forms are shown on 

 plate 35. Many of the smaller specimens are unicolored chocolate- 

 brown all over ; others have a light line at the periphery. H. fun- 

 iculata Pfr. should undoubtedly be included in the synonym. Tryon 

 has followed Pfeiffer in placing it under Dorcasia (see Manual, Vol. 

 Ill, p. 214, pi. 49, fig. 16). This small form is distinctly angulated 

 at the periphery. A specimen before me measures alt. 17, diam. 27 

 mill. 



H. FORSTERIANA Pfeiffer. PI. 21, figs. 50, 51 ; pi. 66, fig. 66. 



Shell depressed, umbilicated, rather thin, microscopically gran- 

 ulated, yellowish-fawn color with brown bauds above and below a 

 light peripheral zone, and a narrow dark margin to the suture ; lip 

 narrowly expanded. 



The form is more depressed than H. semicastanea, and the texture 

 thinner ; the spire is low, scarcely conoidal, a little obtuse at the 

 apex ; the periphery often has the mere suggestion of a keel. The 

 color is pale yellowish ; below and above the peripheral light zone 

 there are rather broad brown bands, fading into the light ground- 

 color on the base and near the narrow sutural band ; the inside of 

 the umbilicus is a little darker than the base. The surface is shin- 

 ing, very densely and regularly granulated, the granulation obsolete 

 or wanting on the base ; whorls 6, slightly convex, slowly widening, 

 the last a little descending in front. Aperture broad lunate, oblique, 

 banded inside ; peristome narrowly expanded, not thickened, dilated 

 and impinging upon the umbilicus at the insertion. 



Alt. 19, diam. 30 mill. 



Barrow, Howick and Percy Islands, Northeast Australia. 



H. Forsteriana PFR., Proc. Zool. Soc. Lond. 1851, p. 254 ; Monogr. 

 iv, p. 174; v, 377; Conchylien Cabinet, p. 373, t. 140, f. 9, 10. 

 'Cox, Monogr. Austr. Land Sh., p. 42, t. 4, f. 8. DOHRN, Mai. Bl. 

 ix, 1862, p. 210 ; and in continuation of Conchyl. Cab., p. 582, t. 

 171, f. 8-12. HEDL.EY, Proc. Roy. Soc. Queensl. v, p. 58, 1888. 

 H. hetcera PER. P. Z. S. 1860, p. 154. 



