144 AMPHIDROMUS, GROUP IV. 



others of stouter contour, of a very pale buff tint, almost white (pi. 

 50, figs. 31, 33, 34). This may be called color var. paUidnlus. Two 

 specimens measure : the stoutest, alt. 44, diam. 26^, longest axis ol 

 aperture 24^ mill.; and the most slender, alt. 46, diam. 25, longest 

 axis of aperture 23^ mill. A dextral specimen of this color-form (fig. 

 31) is more slender, alt. 40, diam. 20, aperture 20 mill. This is the 

 only dextral chlon's I have seen or heard of, and may perhaps be re- 

 garded as an atavistic individual. Another shell (fig. 30) is quite 

 small, and pale lemon-yellow. 



BASILAN. The Steere Expedition also collected examples of 

 chlon's on Basilian island (figs. 32, 35, 36-38), where Semper did 

 not find it. They aie identical in form with Samboanga shells, but 

 vary in color as follows :(a) Color of the typical yellow tint, but 

 rapidly fading to white on the spire, pi. 50, fig. 35. (b) Pile citron 

 or greenish-yellow, the spire white, fig. 37. (c) Similar to color-var. 

 palliduhts, but with a slightly darker sutural border and no white 

 band, (d) Pure white throughout, color-var. purissimus, fig. 32. 

 (e) Pale yellow or rufous, with oblique reddish-brown streaks on the 

 spire or throughout, the suture narrowly marked with the same, 

 color-var. colista, fig. 36. (f) Brilliant rose-pink, with white sub- 

 sutural band and darker sutural line to the apex, color-var. rosa, 

 fig. 38. 



Figure 28 is a copy of Reeve's type figure. Figs. 29-31, 33, 34 

 are from Samboanga, 32, 35. 36-38 from Basilan specimens. 



A. ROESELERI Moellendorff. 



Shell sinistral, half-covered perforate, ovate-conic, solid, trans- 

 versely lightly striatulate, decussated by delicate and close but very dis- 

 tinct spiral lines; satin-like, white. Spire moderately long, with 

 slightly convex sides and obtuse apex. Whorls 6, moderately con- 

 vex. Aperture moderately oblique, subauriform ; peristome rather 

 widely expanded, white-lipped, a little reflexed, columella straight, 

 forming a rather distinct angle with the basal margin, heavily cal- 

 loused, dilated "above, revolute, nearly covering the perforation. Alt. 

 47, diam. 27, aperture 24.5 mill, long, 18 wide (Mlldff.}. 



Sulu Island (I. Roeseter). 



A. roeseleri MOELLENDORFF, Nachrbl. d. D. Malak. Ges. xxvi, p. 

 210 (Dec. 1894), FULTON, Ann. Mag. N. H. (6), xvii, p.. 75. A. 

 maculiferits var., SMITH, Ann. Mag. N. H. (6), xiii, p. 55, pi. 4, f. 

 9, 9a (Jan., 1894). 



