HALIOTIS. 119 



striped with scarlet, and in the specimen before me the closed per- 

 forations are scarlet ; spire pink. Surface having numerous unequal 

 spiral threads, decussated by distinct, close growth-stria?, as in H. 

 rosacea; there are also inconspicuous short folds radiating from 

 the suture on the earlier portion of the body-whorl, and just outside 

 of the median spiral depression on the body. Inside bright silvery, 

 with green and red reflections, the nacre having spiral folds. Col- 

 umellar plate flat but rather narrow, obliquely subtruncate at base. 

 Cavity of spire visible. Peforations 6, nearly circular, separated by 

 spaces about as wide as the*" holes. 



Length 42, width 29, convexity 8 mill. 



Australia. 



H. cocco-radiata Reeve, Conch. Icon., f. 46 (1846). — Wein- 

 kauff, Conchyl. Cab., t. 23, f 3, 4. 



The decussated sculpture, scarlet markings, etc., are characteristic. 

 The cavity of the spire is wholly visible, not concealed as it is in H. 

 rosacea ; and the columellar plate is rather narrow. The figure of 

 the interior of this species (fig. 16) has been united with the exterior 

 view of H. cruenta by the artist. The smaller size separates the 

 sjiecies from H. ncevosa, which is closely allied. 



H. lauta Reeve. PL 3, fig. 8. 



Shell ovate, anteriorly attenuated, undately swollen, spirally 

 ridged, ridges very fine, close-set, decussated with minute stria, per- 

 forations rather large, five open. Irregularly marbled with red and 

 yellowish-white. (Reeve.) 



Swan River, Australia. 



H. lauta Reeve, Conch. Icon., t. 17, f. 68, 1846. 



Group of H. excavata. 



H. excavata stands in that neutral borderland which forms a sort 

 of Alsace and Loraine between Haliotis proper and Padollus. 

 Like the group of H. ncevosa, which also occupies this debatable ter- 

 ritory, the H. excavata has been from time to time annexed to one 

 or the other group, according to the fancy of systematists mapping 

 these regions. 



H. excavata Lamarck. PL 9, fig. 51 ; pi. 49, fig. 23. 



Shell nearly circular in outline, elevated, somewhat turbinate, the 

 distance of apex from margin between one-third and one-fourth the 

 greater diameter of the shell. Body-whorl rounded, convex above; 



