120 A MANUAL OF AMERICAN LAND SHELLS, 



AOLiAIA, Albers. 



Animal heliciform, as in Patula; mantle subcentral. 



Shell umbilicate, orbicularly convex, striatulate, banded; wborls 

 4^-C, the last deeply deflexed in front; aperture lunate-ovate, very 

 oblique ; peristome thickened, expansively retlexed, white, its margins 

 approaching, that of the columellar dilated, reflexed, free, partially 

 covering the umbilicus. 



Within our limits this genus is found only in the Pacific Eegion. A 

 few Mexican and South American species are also known. 



Jaw thick, high, arched, ends but little attenuated, blunt; cutting 

 Fig. s9. edge without median projection; anterior surface with 

 stout, separated ribs, denticulating either margin, from 5 

 to 9 in A. infumata (Fig. 89), about 6 in Jidelis. The other 

 American species, H. Hillebrandi, I have not examined. 

 ^"'^ mate"'"'^"' Lingual membrane long and narrow. That of Hille- 

 hrandi not examined, those of infumata and Jidelis agreeing in 

 their general characters. The centrals have a base of attachment 

 longer than wide, with incurved lower margin and expanded lower 

 lateral angles; upper margin broadly reflected ; reflection short, stout, 

 with no side cusps or cutting points, but a very stout, short median 

 cusp, bearing a short cutting point. Laterals like the central'!, but 

 asymmetrical by the base of attachment wanting the inner, lower lateral 

 expansion ; it is, however, unusually developed on its inner side mar- 

 gin ; first marginals differing from the laterals by the equaling of the 

 reflection and base of attachment, the lesser development of the cusp, 

 and greater development of the cuttiug point, which is bluntly bifid, 

 the inner division the smaller. On some of the first marginals of infu- 

 mata there is a small side cutting point. Marginals low, wide, the re- 

 flection equaling the base of attachment, and bearing one loug, oblique, 

 wide, bifid cutting i)oint, the inner division the smaller, and one or two 

 short, sharp, side cutting points. There is great variation in the cut- 

 tiug points. 



A comparison of the two figures in Terr. Moll., V, will show a longer 

 base of attachment in Jidelis, with a line of re- enforcement or duplication 

 to its upper margin. As with all species, there is much variation in 

 the length of the cutting point in centrals and laterals, and their 

 arrangement and development in the marginals. 



Of the dentition of the other species of Aglaia foreign to our limits 



