HELCIONISCUS. 143 



posed, which are transparent when held up to the light, those near 

 the margin elongated. Aperture ovate, the margin slightly irre- 

 gular ; interior a very dark claret-color, with brilliant silky and 

 golden reflections, and yellow spots, corresponding to those of the ex- 

 terior ; central spatula dull buff-color. (Old.) 



Length H, breadth li, alt. I inch. 



Auckland Is. (Gld.) ; Campbell and Macquarie Is. (Button.) 



P. illuminata GLD., Proc. Bost. Soc. N. H. ii, p. 149, (1846) ; 

 Exped. Moll. & Sh., p. 340, atlas f. 441. HTJTTON, Trans. K Z. 

 Inst. xv, t. 16, f. c (dentition). Patinella illuminata HUTTON, Proc. 

 Linn. Soc. N. S. Wales, ix, p. 376. ? Patella terroris FILHOL, Compt. 

 Rend, xci, (1880.) 



* * * 



Australian species. 



H. LIMBATA Philippi. PI. 71, figs. 53, 54, 55, 56 ; pi. 17, figs. 28, 



29. 



Shell solid, oval, the apex near the front third ; sculptured with 

 from 21 to 31 broad rounded ribs. Brown or reddish, the intervals 

 between the ribs brown-striped. Apex eroded. Edge scalloped by 

 the ribs. 



Inside whitish, tinted with flesh-color or lilac, the central callus 

 generally opaque-white mixed with bluish, becoming olive toward 

 its edges. There is a distinct yellow or brown border, within which 

 the stripes of the exterior make a ring of vivid blotches, these stripes 

 being also, at times, visible through the tinted lining of the shell. 



Length 47, breadth 41, alt. 20 mill. 



Length 59, breadth 52, alt. 29 mill. 



Port Lincoln, S. Australia ; Tasmania. 



P. limbata PHIL., Abbild. u. Beschreib., iii, p. 71, Patella t. 3, f. 

 2. REEVE, Conch. Icon. f. 29. ANGAS, P. Z. S. 1865, p. 185. 

 TENISON- WOODS, Proc. Roy. Soc. Tasm. 1876, p. 48 (animal). 



A large, solid species. The broad, rounded ribs, narrow inter- 

 stices striped with brown, and distinct internal border are charac- 

 teristic marks of this species. The eroded apex is usually stained 

 with bluish. The number of ribs is excessively variable, sometimes 

 as many as 37 being developed. 



H. LATISTRIGATA AngaS. 



Shell very similar to P. limbala, but more elongated ; liver-colored, 

 rayed with a few very broad brown-black stripes. Ornamented with 



