8S HALIOTIS. 



threads; crossed by a few radiating folds marking the positions of 

 former peristomes, holes five. 



The shell is oval, both sides curved ; quite depressed and flat, 

 with a wide superficial spiral depression around the middle of the 

 upper surface. The entire surface has spiral cords and stria?. The 

 sculpture has a clear-cut appearance, as if engraved. The area be- 

 tween the row of holes and the columellar margin is wider than 

 usual ; it has a strong spiral cord midway, above which it is con- 

 cave, and below which it is convex. In the middle of the concave 

 portion there is another strong spiral. The color in the typical 

 form is a clear light green, becoming reddish on the spire, and hav- 

 ing a pink area on the part of the body- whorl adjacent to the spire. 

 Inside silvery, very bright and somewhat iridescent. Columellar 

 plate narrow, obliquely truncated. Cavity of spire small. 



Length 47, width 32, convexity 8* mill. 



Habitat unknown. 



H. bistriata GMEL. in Linne, Syst. Nat. xiii, p. 3689. WEIN- 

 KAUFF, Conchy 1. Cab., p. 9, t. 3, f. 1. 



This is the true bistriata of Gmelin, agreeing exactly with the fig- 

 ure of Martini to which he refers. I do not know whether the H. 

 bistriata of Reeve and of Sowerby (see pi. 4, figs. 11, 12) is the same 

 but think it likely. A specimen before me, drawn on pi. 48, figs. 

 14-16, agrees with the figure in Chemnitz in a surprisingly minute 

 manner. Another is flecked and speckled all over with brownish- 

 orange on a pink-white and pale green ground. It is very delicate 

 and pretty in coloration, and may be known by its flatness, the wide 

 bi-striate area below the holes, and rather narrow columellar plate. 

 The spirals are minutely granose. on the spire ; and some shells have 

 very close fine distinct growth strise all over. 



Group of H. stomaticeformis. 



This comprises a number of small shells, the smallest of the gen us 

 distributed from Japan to New Caledonia and eastward to the 

 Viti Islands. The spire is somewhat raised, frequently notably so ; 

 the sculpture consists of sharply-cut spiral cords and more or less 

 prominent radiating folds ; the holes are few in number and more or 

 less tubular. It may be doubted whether all of the species here 

 admitted are valid. 



H. squamata, a larger species than the others, and with numerous 

 perforations, seems to group with the stomaticeformis. 



