80 
Tas. LXXXVII. ACIONA SCALARIS. 
A. testa albida costis superne subreflexis ; interstitiis glabris. 
Turbo scalaris. Linn. Syst. Nat. xii. 1237. — Mart. Conch. A, 
t. 152, f. 1426. 
De rechte Wendeltrap. Rumph. Amb. rarit. tab. AQ, fig. a. 
Scalaria conica. Lam. Syst. des Anim: sans Vert. 88. 
Scalarus scalatus. De Mont. Conch. Syst. 2, 295. 
Habitat in Amboina. 
COMMON WENDLETRAP. 
Shell whitish, with the ribs slightly reflexed above ; the in- 
termediate spaces smooth. 
This shell was formerly esteemed as a valuable rarity, 
and was to be found in but few cabinets. It is nowa 
common shell; yet very great prices are often given for 
large and perfect specimens. 
The Museum of Mr. Bullock contains the largest known 
specimen of this elegant species, which was purchased at a 
sale for twenty-seven pounds ; but it is now estimated as 
worth more than double that sum. 
It is commonly called the true Wendletrap, and is also 
known to collectors by the name of royal stair-case shell. 
