88 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 8J mill. 



Habitat unknown. 



H. bistriata Gmel. in Linne, Syst. Nat. xiii, p. 3689. — Wein- 

 kauff, Conchyl. 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 stria? all over. 



Group of H. stomatia'formis. 



This comprises a number of small shells, — the smallest of the genus 

 — distributed from Japan to New Caledonia and eastward to the 

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

 the sculpture consists of sharply-cut sjfiral 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 stomatia'formis. 



