HELIX-CHLORITTS. 263 



that Trachia has already been monographed in the MANUAL (vol. 

 IV) by Mr. Tryon, and I do not wish to duplicate species once 

 treated. 



H. SPINEI Cox. PI. 52, figs. 90, 91, 92. 



Shell openly nmbilicated, discoid, flattened on the top, yellowish- 

 brown, covered with coarse, long bristles in regular rows ; whorls 5, 

 gradually increasing, rounded, last descending in front, suture deep 

 and narrow; aperture diagonal, rounded; peristome simple, lip 

 everted, columellar margin not dilated. (Co.r.) 



Alt. 0'23, greater diain. 0*55, lesser 0*44 inch. 



Port Curtis, Queensland, Australia. 



H. hystrix Cox, Monogr. Austr. L. Sh. p. 48, t. 17, f. 5, 5a, 5b, 

 (preoc.). H. spinel Cox, L c., p. 111. 



Differs from its allies in being more discoidal and bristled. 



H. PORTERI Cox. PI. 58, figs. 23, 24. 



Shell depressed-globose, half-covered umbilicate, thin, dark red- 

 dish-chestnut ; surface densely beset with very short, delicate hairs, 

 the scars of which are seen as minute granules in regular oblique 

 rows on the earlier whorls of the spire. Whorls 4*. 



The form is depressed, spire low-conoidal, apex obtuse, planorboid ; 

 whorls, especially the earlier, very convex, separated by deep sutures; 

 last whorl somewhat compressed above and below, but not carinated, 

 its latter half decidedly swollen, abruptly descending in front, and 

 narrowly constricted just behind the lip. Aperture very oblique, 

 transversely oval, dark within ; peristome thin, narrowly expanded, 

 white or nearly so, the columella dilated in a triangular plate, 

 partly or nearly concealing the umbilicus. 



Alt. 12, greater diam. 16, lesser 14* mill. 



Upper Clarence River at Guy Faux; Upper Richmond River at 

 Cowlong ; Upper Nerang Creek, Queenland. 



H.porteri Cox, P. Z. S. 1866, p. 373; Monogr. Austr. L. Sh., p. 

 48. HEDLEY, Proc. Roy. Soc. Queensl. 1889, p. 249, plate xv 

 (anatomy.) 



Allied to H. brevipila but much larger, the earlier whorls more 

 distinctly granulated. It has about the size and color of H. man- 

 sueta, but differs in being hairy and less widely umbilicated. 



