UMBONIUM. 451 



f. 6. SOWERBY, Thes. Conch, v, p. 135, t. 472, f. 6-8 ; in Conch. 

 Icon, xx, f. 6. Rotella vestiaria SOWB., Thes. Conch, v, p. 135, 

 f. 1-5 ; in Conch. Icon. f. 12. Rotella rosea LAM., /. c., No. 2. 

 Globulus vestiarius Linn., PHILIPPI, Conchyl. Cab., p. 45, t. 7, f. 

 1-10. G. elegans Beck, PHIL., I. c., p. 46, t. 7, f. 16-20. Um- 

 bonium depressum A. ADAMS, P. Z. S. 1853, p. 188. Rotella 

 depressa Ad., SOWERBY in Conch. Icon., f. 2. Globulus australis 

 PHILIPPI, Conchyl. Cab., p. 48, t. 7, f. 21-23. Globulus parvulus 

 Anton, PHILIPPI, Conchyl. Cab., p. 48, t. 7, f. 11, 12. 



An excessively variable form. Sometimes the spire is scarcely 

 more convex than the base, though always conical. Usually it is 

 more elevated. U. depressum Ad. (pi. 58, figs. 24, 25) is a depressed 

 form. The colors are indescribably variable, usually very vivid. 

 The following are the more usual patterns : 



(1) Uniform white, rose-color, fawn or flesh-color, or slaty- 

 blackish. (2) Marked with close, zigzag radiating lines or stripes 

 above, the base white or colored like the lines. (3) Radiately lineo- 

 late, the lines interrupted by spiral zones of rose or white. (4) 

 Finely mottled above, with a peripheral zone of large spots, or a 

 white-edged girdle of red. 



There are any number of modifications and combinations of these 

 patterns. I am unable to separate U. elegans from U. vestiarium, 

 even varietally. 



U. CALLOSUM Sowerby. PL 59, fig. 36. 



Shell depressed, solid, outer lip thin ; white or yellowish, finely 

 marbled all over with black, gray or ashen, sometimes with a series 

 of white blotches at the periphery ; basal callus white, yellow, 

 reddish or black. Surface polished, smooth ; spire low, conical, 

 acute ; whorls 6-7, slightly convex, separated by simple, linear 

 sutures ; last, whorl very rapidly widening, large, dilated, flat on the 

 base, except for the large circular callus, which is excessively heavy 

 and convex ; aperture oval-truncate. Alt. 8, diam. 13 mill. 



Indian Ocean. 



Rotella callosa SOWERBY, Thes. Conch, v, p. 135, t. 472, f. 26 

 (1887, date of title-page). 



The texture is like U. vestiarium ; the last whorl is very wide, and 

 the umbilical callus far heavier, more convex, than in any other 

 known species ; 6 specimens are before me, bearing the rather 

 indefinite habitat given above. 



