SOLARIELLA. 323 



smaller than in the last, bordered by two nodulous ribs with a 

 remarkably deep groove between them ; aperture as in the last, but 

 not so distinctly angulated ; shell variously painted with brown on 

 a yellowish-white ground ; one specimen has five distinct brown 

 patches on the upper side of the last whorl, another has more 

 numerous radiating brown streaks ; the base is whitish, and in 

 adults there is a thickening of the inside of the aperture all around, 

 but least on the pillar. 



Alt. 4'5, maj. diam. 5'0. Diam. of aperture, 2'25 ; of umbilicus, 

 1-0 mill. (Dall) 



Off Santa Cruz, 115 fms. ; Off North Carolina Coast, 25-124 fms. 



Margarita maculata DALL, Bull. M. C. Z. ix, p. 43, 1881, not of 

 Searles Wood, 1842. M. lacunella DALL op. tit., p. 102. Solariella 

 lacunella DALL, Blake Gasterop., Bull. M. C. Z. xviii, p. 381, t. 21, 

 f. 1, 1889. 



This species is nearest to Tr. cinctus Phil., but differs in so many 

 details of sculpture that I do not see my way clear to unite them at 

 present. The coloration is variable ; some are clouded with olive 

 and others with pinkish brown. A variety depressa has the spire 

 low and somewhat tabulated by a smooth space betw r een the suture 

 and the spiral ribs. (Dull.) 



S. IRIS Dall. PL 51, figs. 30, 31. 



Shell thin, brilliantly nacreous, inflated, depressed-conical, five 

 whorled ; spire obtuse ; nucleus polished, smooth, very minute ; re- 

 mainder of shell sculptured with fine revolving lines, subequal, 

 about as wide as the interspaces, about eighteen at the beginning of 

 the last whorl ; these are crossed by slight plications, beginning near 

 the suture, becoming nodulous on a single prominent thread a little 

 way from the suture (which is thus made to appear somewhat 

 channelled), becoming faint about the middle of the upper side of 

 the whorl, and entirely disappearing before reaching the periphery ; 

 the revolving lines are fainter on the rounded base; the umbilicus 

 is wide and funnel-shaped, bordered by a strong keel with about 

 twenty-five rounded nodules, the inner walls of the umbilicus with 

 strong revolving lines delicately reticulated by the lines of growth. 

 The whorls are rounded, with no carina at the periphery ; the pillar 

 thin, arched not reflected ; the aperture nearly round, but angulated 

 above by the sutural thread, and below by the umbilical keel ; edges 



