1905.] NATURAL SCIENCES OF PHILADELPHIA. 



cvlindric in each whoi-1, and in the last encircled by a callous corf or 

 lamella, extending horizontally upon the reflexed columellar lip. Type 



A. discus. , ,. .f • * r^oi.,, 



A. di.cm P. and V. Oahu. A. hcl,alonn,s Anc. Oahu. 



A.dato(Pfi-.)P-andV. Lanai. .1. r« hykes. Oahu. 

 Amastra<HeUoama5tra)dis«u. n..p. PL XXXVIII. fiB=. 1. 2, 3- 

 "thin and tra,.ile. openly nmbilicate. flat, ^'™™. --^ 'j^^'^^ 

 the periphery carinate, the keel obtuse. Uniform dull brown. Whorls 

 r 1 the fii-st hardly convex, marked with faint growth-lmes, 

 r^ th 1 fl"«/marked with oblique growth-lines its outer 

 ire disfmctly mm-sined. corf-like. The next whorl ,s slightly convex, 

 St rpXherll corf or margin, and has rather rude wrinkle stria>^ 

 T X wdiorl becomes more swollen above in part rising *ove the 

 level of the preceding whorls, and is rather rudely wrinkled The angu 

 W -trilten is on a level with the flat spire. The umbilicus is deep 

 t d s b vh, dric. The aperture is oblique, wider than high outer and 

 b a mar ins thin and simple, columellar margin di ated, bearing an 

 ac rte sublori^-mtal white lamella. Alt. 3.4, diam. 10 miiL 



Waianae, Oahu. Types No. .58,158, A. N. S. P., received from D. D. 



'^ Tto'curious snail differs from .1. alMa by its flat spire, irregular 

 gil th and larger umbilicus. It is much more depressed than 4. hehc. 



jonnis Anc, with fewer whorls. „ „ „ - vnl XIV n 159 



Amastra rex Sykes (Ann. and Mag. N H., Se . 7- Vo' . ^IV^P^ S^, 

 10041 is a larger species with peripheral appendages as in Pterodv>cus 

 ! i; It Teems'to have a much smaller umbilicus than A. c;««s, 

 but neither the description nor figure are clear on this point. 



^ N lofo rpfr ?^ P & V PI. XXXVIII, figs. 4. 5, 6. 

 Amastra(Hehcamastra)alat (H. )P^^. Hawaiiensis, MoUusca, p. 355 



Aviastra {Knumn) (data i tr., ^> iveb, rau 



(no description). .^r-a ^ q-? 



? Helix alata Pfr., P. Z. S., 1856, p. 33. 



Shell thin umbilicate, biconvex, the base more convex than the spu-e 

 pe™ an-te. B'rown, nearly lusterless. mods 4 the firs 

 penpneiy obliquely striate, with 



rp^fplTr^t^a!^^^^^^^^^ 



7Z convex near the periphery but without a margimng coid Last 

 wtel ba"dy convex, sloping above, densely marked with growth-st™ 

 Ton ite later portion with some coa.^e oblique wrinkles, convex be- 

 nlh Umbcu" rather narrow and tubular. Aperture wider than 

 hS tire dilated columellar lip bearing an acute, subhon.ontal lamella. 

 Alt. 4.3, diam. 8.2 mm. 

 37 



