TROCHIDAE 



111 



Middle of whorl with a strong, sharp, smooth or beaded, spiral thread. Base 

 of shell smoothish except for one smooth spiral thread near the periphery and 

 one heavily beaded cord bordering the deep, round umbilicus. Entire shell 

 with numerous microscopic incised lines. Very commonly dredged from 35 

 to 150 fathoms, but also recorded from 683 fathoms. 



Solariella peramabilis Carpenter Lovely Pacific Solarelle 



Figure 31b 



Alaska to San Diego, California. 



^ to % inch in length, equally wide, solid, semi-gloss. Aperture circular. 

 Umbilicus fairly wide, round, very deep. Whorls 7, shouldered just below 

 the suture by a flat shelf. Lower % of whorl with numerous weak spiral 

 cords that are smoothish in the last whorl but crossed by numerous axial rib- 

 lets in the early whorls. Color tan with light-mauve stains and mottlings. 

 Interior iridescent. Moderately common from 20 to 339 fathoms. 



Figure 32. a, Gaza ivatsoni Dall (nat. size); b and c, Solariella lacunella Dall 

 X4; d and e, Microgaza rotella Dall X4. All from the Atlantic. 



Genus Microgaza Dall 1881 

 Microgaza rotella Dall Dall's Dwarf Gaza 



Figure 32d, e 



North Carolina to south Florida and the West Indies. 



% inch in diameter, spire flat, surface smooth except for a spiral row of 

 low pimples just below the suture. Whorls about 5. Umbilicus fairly wide, 

 very deep, its squarish edge bearing numerous, neat, rounded creases. Colu- 

 mella straight. Color whitish gray with a beautiful opalescent sheen, espe- 

 cially inside the aperture. Top of whorls colored with chestnut, zebra-like 

 axial stripes. Very commonly brought up in dredging hauls off A4iami from 

 50 to 100 fathoms. The form i?iornata Dall lacks the pimples just below the 

 suture. 



