178 HELIX-HADRA. 



Not known except by the original description. Pfeiffer and Tap- 

 parone-Canefri place it in Camcena, but it is more likely, if found, 

 to prove a Hadra. 



Subsection XANTHOMELON Von Martens, 1861. 



Xantliomelon MART, in ALBERS, Die Heliceen, 2te Ausgabe p. 174 

 (as sect, of Cochlostyla) , type, H. pomum Pfr. VON MARTENS, Mal- 

 akozoologische Blatter, xvi, p. 77, 1869. Galaxias (in part) Cox, 

 Moiiogr. Austr. L. Sh. 



A group of globular shells, especially characteristic of north and 

 northeast Australia. They are connected with the typical manifes- 

 tations of Hadra by such species as H. bitceniata, etc. The anatomy 

 is similar to that of Hadra and Spliwrospira. 



The species are characteristic mainly of central and north Aus- 

 tralia, comparatively arid regions in which the Sphcerospira and Ba- 

 dite? sections of Hadra are but sparingly or not at all represented. 



H. POMUM Pfeiffer. PI. 38, figs. 73, 74. 



Shell nearly covered umbilicate, globose, yellow, often reddish on 

 the spire ; not spirally striated ; whorls 4i to 5 ; lip pure white, 

 narrowly expanded all around, broad and flattened at the columella. 



The shell is globular, a little depressed, pure white under the epi- 

 dermis, which is yellow, a little tinged with olive. Surface shining, 

 having oblique growth-wrinkles, and little indentations or dents in 

 places ; on the spire granulated more or less distinctly. Spire low ; 

 apex obtuse ; suture rather deeply impressed. Whorls convex, the 

 last subglobular, descending in front, a little constricted just behind 

 the lip. Aperture oblique, round-lunate, white within; lip narrow- 

 ly expanded, a little thickened within, the columella dilated into a 

 broad flat plate which partly or almost wholly conceals the umbili- 

 cus ; columellar edge bearing a blade-like callus. 



Alt. 36, greater diarn. 38, lesser 34 mill. 



Arnhem Land, North Australia. 



H. pomum PFR., Synibolse ii, p. 37 ; Conchylien Cab. p. 318, t. 55, 

 f. 11-13; Monogr. i, p. 320. PHILLIPPI, Abbild. i, t. 2, f. 8. 

 REEVE, Conch. Icon. f. 362. Cox, Mon. Austr. L. Sh. p. 40, t. 4, f. 

 7. TATE, Trans. R. S. S. Austr. v, p. 49. H. urvillei Hombr. & 

 Jacq., Voy. Pole Sud, Moll., t. 3, f. 1-3. H. pseudomeadei BRAZIER 

 in Harcus' S. Austr. Hand-book (name only). And in all proba- 

 bility, H. splueroidea LE GUILLOU, Revue Zoologique, p. 188, May, 

 1845. 



