52 PROCEEDINGS OF THE NATIONAL MUSEUM vol.89 



HALIOTIS RUFESCENS HATTORII, new subspecies 



Plate 8, Figures 4-6 



Shell small, oval, rather flat, spire depressed, with a slight auricle 

 where the outer lip joins the preceding whorl at the summit. The 

 color of the first half of the shell is blue, slightly variegated with red. 

 The last half is banded with zones of red and bluish white. The sculp- 

 ture consists of irregular lines of growth and indications of axial wav- 

 ing. The spiral sculpture consists of low, flattened threads, which are 

 not quite so wide as the spaces that separate them. These, in combina- 

 tion with the incremental lines, give the surface a somewhat clothlike 

 texture. The siphonal angle bears moderately elevated craters, the 

 last four of which are open. Between this siphonal line and the edge 

 of the aperture the shell is rounded and marked like the surface 

 posterior to the siphonal line. The entire outer surface has a waxy 

 appearance. The interior is pearl-gray with iridescent tints, the 

 outer edge of the outer lip being pale reddish. The right edge of the 

 aperture is slightly crenulated; the left edge is rather broadly ex- 

 panded and flattened, sloping outward, the shelf being about the same 

 width on the parietal wall. Muscle scar poorly differentiated. 



The type, U.S.N.M. No. 535761, was collected by Mr. Hattori, an 

 abalone diver, near Santa Barbara, for whom I take pleasure in 

 naming the form. Wlien placed on the aperture it yields the follow- 

 ing measurements: Height, 18 mm.; greater diameter, 100 mm.; 

 lesser diameter, 74 mm. 



This subspecies can be differentiated easily from typical Haliot'is 

 rufesceTis Tujescens by its very flat shape, the very poorly elevated 

 spiral threads, the waxy surface, and by lacking the elevated tumid 

 area between the siphonal line and the edge of the aperture. From 

 H. rufescens walallejisis it is easily distinguished by its much broader 

 shape and feebler sculpture. 



HALIOTIS PONDEROSA C. B. Adams 



Plate 7 



1848. Haliotis ponderosa C. P>. Adams, Amer. Jonrn. Sci. and Arts, ser. 2, vol. 

 6, pp. 138-139. 



Shell large, very heavy, strongly inflated, spire well elevated. The 

 exterior is brownish red, rough, and somewhat worn. It shows 

 irregularly developed and distributed, weakly irregularly nodulose 

 axial ridges and very rough incremental lines, as well as indications 

 of spiral cords. Anterior to the line of siphonal craters, the last four 

 of which are open, the shell is moderately elevated and strongly 

 rounded. On the early part of the last turn it has a broad, feebly 



