132 



HELCIONISCUS. 



border. The large central area is either cream-colored with a dis- 

 tinct dark laciniate outline, or is of an umber-brown, lighter in the 

 depth. From each angle of the anterior head-segment of the central 

 callus, a narrow dark band radiates, passing through the dark zone 

 which surrounds the muscle-scar. 



Length 100, breadth 85, alt. 40 mill. (no. of riblets 53.) 

 Length 90, breadth 75, alt. 40 mill. (no. of riblets 50.) 

 Length 88, breadth 77, alt. 40 mill. (no. of riblets 48.) 



Bonin Is., north of Japan. 



Patella (Helcioniscus) boninensis PILSBRY, The Nautilus, Nov- 

 ember, 1891, p. 79. 



This magnificent limpet approaches the P. nigrisquamata of Reeve, 

 but may be readily distinguished by its much larger central callus 

 inside, the two diverging brown streaks mentioned in the description, 

 etc. The two forms are moreover widely separated geographically. 



The specimens were seen and purchased by Mr. Frederick 

 Stearns, of Detroit, Michigan, at the Third National Exhibition at 

 Tokyo, 1890. They are called in Japanese, Yome-gai-sara, "Bride- 

 cup shells." 



H. STEARNSII Pilsbry. PI. 48, figs. 16, 17, 18. 



Shell solid, elevated-conical, oval ; apex a little behind the front 

 third of the length; front slope straight or concave, posterior slope 

 convex. Sculptured with about 51 unequal closely nodulose ribs, 

 separated by deep interstices. Surface lusterless, soiled whitish, hav- 

 ing irregular rays of reddish-brown, and speckled with the same on 

 the upper part of the cone. 



Interior bluish-white rayed or mottled with darker by the dark 

 rays of the exterior ; central area strongly defined, reddish-brown 

 with a white stain in the cavity of the apex ; edge of the shell 

 scalloped. The dark rays become vivid deep brown or black at the 

 border, the dark blotches alternating with white. 



Length 41, breadth 31 J, alt. 27 mill. 



Length 38, breadth 29, alt. 21 mill. 



Province of Kii, Japan. 



P. (Helcioniscus') Stearnsii PILSBRY, The Nautilus, Jan., 1891, 

 p. 100. 



This handsome shell is sculptured with closely nodulose ribs, 

 obscurely alternating in size. There are 10 or 11 irregular dark 

 rays on the outside, much broken into spots on the upper part of the 



