HALIOTIS. 1 23 



numerous descending stripes alternately darker and lighter. In- 

 side silvery, sculptured to correspond with the spiral and radiating 

 ribs of the outside, iridescent. Columellar shelf narrow, flat. Per- 

 forations low-tubular, about 6 open. 



Length 47, width 34, convexity 10 mill. 



Length 90, width 70 mill. (Reeve's figure.) 



Australia. 



H. emmce Gray in Reeve, Conchol. Icon., 1. 10, f. 29. — Sowerby, 

 Thes. Conch, v, t. 2, f. 16. — Weinkai-ff, Conchvl. Cab., p. 50, t. 

 22, f. 1, 2. 



The specimen described above and figured on pi. 49, figs. 27-29, 

 is much smaller than that figured by Reeve. The species is inter- 

 mediate between H. parva and H. tricostalis, having the general 

 appearance and color of the first, but agreeing with the last-named 

 in having radiating lamella? or folds. 



H. tricostalis Lamarck. PL 16, figs. 84, 85. 



Shell rounded-oval, depressed, having a strong spiral rib on each 

 side of the row of perforations, and prominent elevated radiating 

 lamella? around the spire ; 5 to 6 open perforations. 



The shell is moderately large but thin, of the depressed, irregularly 

 oval shape common to all Padollus. Color " reddish or variegated 

 olive and green." Surface having a strong rounded ridge inside of 

 the row of elevated tubular holes, and a smaller, nodose ridge outside 

 of it; above finely striated spirally, and with coarse raised lamellae 

 between the spire and the inner spiral rib. Inside it is silvery and 

 very iridescent, with excavations corresponding to the elevations of 

 the outer surface. The columellar plate is narrow, oblicmely trun- 

 cated below. Perforations tubular, 5 or 6 open. 



Length 74, width 53 mill. 



Australia ; Java. 



If. tricostalis Lamarck, Anim. s. Vert, vi, p. 218. — Desii. in 

 Lam., ed. 2, ix, p. 30. — AVeinkauff, Conchylien Cabinet, p. 13, t, 

 5, f. 3, 4. — Padollus rubieundus Montfort, Conch. Syst,, p. 114, 

 115 (very doubtful/). — H. rubieundus Lam., Reeve, Conch. Icon., 

 f. 5. — H. canaliculata Schubert A Wagner, Fortsetz. des Conch. 

 Cab. xii, p. 177, t. 224, f. 3088, 3089.— Padollus tricostalis H. & A. 

 Ad., Genera, p. 443, t. 15, f. 7.— Chenu, Manuel i, f. 2746, 2747. 



Easily known by its three spiral ribs and the radiating lamella? 

 above. 



