274 MINOLIA-CIRCULUS. 



but that is flatter and has a much wider umbilicus. The name is 

 derived from the white spots which fleck the shell. 



T. (Solariella) albugo Watson, Journ. Linn. Soc. Lend, xv, p. 

 94 ; Challenger Gasteropoda, p. 75, t. 6, f. 8. 



Unfigured Species of Minolia. 



Solariella undata Sowerby. Testa subdepressa, umbilico ro- 

 tuudo usque ad apicem perforata, margaritacea, pallide rubescente, 

 spiraliter tenuiter lirata, supra prope suturam angulata ; medio 

 anfractuum carina rotundato-angulata, angulis distanter rubro 

 maculatis ; iuterstitiis rubro undato-lineatis. (SowB., P. Z. S. 1870, 

 p. 251). 



Agulhas Bank, S. Africa. (J/us. Taylor.') 



Genus CIRCULUS Jeff"reys, 1865. 

 Circulus Jeffreys, Brit. Conch., iii, p. 315; Proc. Zool. Soc. 

 1883, p. 94. — Fischer (as subgenus of Gibbula), Man. de Conchyl., 

 p. 824. 



Jeff'reys's diagnosis of this group is as follows : Shell coin-shaped 

 or forming a circular compressed disk, slightly nacreous or pearly ; 

 mouth quadrangular, with a discontinuous peristome ; umbilicus very 

 wide ; operculum multispiral as in other genera of Trochida^. The 

 animal is unknown. 



C. STRIATUS Philippi. PL QQ, figs. 11, 12, 13. 



Shell minute, discoidal, depressed above, broadly umbilicated 

 beneath, subtransparent, quite solid, white ; surface shining ; spire 

 depressed, composed of 4 to 5 convex whorls, traversed spirally by 

 sharp narrow line, 7-9 in number on the upper part of the last whorl, 

 half as many on the penultimate whorl, two or three on the next, the 

 two upper whorls smooth ; the inter-liral spaces delicately obliquely 

 marked by growth strise. The lowest ridge is placed just under the 

 periphery, and is sometimes more prominent than the rest ; suture 

 impressed ; whorls cylindrical, gradually enlarging, the last broadly 

 concave beneath, and smooth save for slight radiating lines of 

 growth ; aperture oblique, rounded-quadrangular ; peristome not 

 continuous ; columella arcuate, subreflexed at the umbilicus ; outer 

 lip slightly sinuous above ; umbilicus broad, deep, showing all the 

 whorls. Alt. '8, diam. 2*5 mill. 



Mediterranean and Adriatic Seas; Atlantic Ocean, England to 

 Morocco. 



