328 SOLARIELLA. 



This species has a close general resemblance to Margarita obscura, 

 Couth., but that is smaller, of slower increase, has. an open umbilicus, 

 is very dull in color, and has much fewer spirals, besides which the 

 whole minute system of spirals is different ; the tubercled spiral, in 

 particular, is the second, not the first, as here, and is not close to the 

 suture. Than Margarita loculosa Gould, which it resembles in its 

 style of spirals, this is more discoidal, and is especially more 

 tabulated below the suture ; the angulation here is on the upper, 

 not on the lower part of the whorl and in that the infra-sutural 

 thread is not beaded. ( Watson.} 



Tr. (Margarita) dnopherus WATSON, Journ. Linn. Soc. Lond. xiv, 

 p. 711 ; Challenger Rep., Gasterop., p. 90, t. 5, f. 3. 



S. AZORENSIS Watson. PL 66, figs. 4, 5. 



Animal dark in color. Operculum rather strong, dark horn- 

 color, of very many narrow whorls, which on the outside are 

 flanged with a thin, narrow, overlying border. 



Shell small, strong, but not thick, conoidal, high, with rounded 

 contours, slightly angulated, scalar, sculptured, whitish, with a 

 slightly flattened base and a small umbilicus. Sculpture: spirals 

 there are very many close, unequal, irregular small furrows, which 

 are feebler on the base and strongest near the suture, which is 

 margined below by a narrow smooth line around the top of the 

 whorl. In the center of the base is an umbilical depression with 

 spiral threads in the bottom, and within this is a strong white 

 porcelaneous spiral cord, which almost closes the umbilicus. Longi- 

 tudinals the top of the whorls is gathered into broad rounded 

 oblique puckers, which die out before reaching the suture or the 

 base. Besides these, the whole surface, spiral furrows and all, is 

 sharply scratched with very close and numerous lines of growth. 

 Color yellowish translucent white, with a dull all pervading nacre- 

 ous gleam. The strong cord which fills the umbilicus is white, as 

 is also the apex. Spire high, scalar, the separate whorls being a 

 good deal sunk into one another, as well as flattened below the 

 suture. Apex small, rounded, the minute embryonic 1} whorls 

 barely projecting. Whorls 6, of regular increase. Slightly flattened 

 below the suture rounded on the contour, barely contracted round 

 their base ; the last is faintly angulated at the periphery, and not 

 much rounded on the base. Suture strongly marked by the con- 

 traction of the whorl above and the margination below. Mouth 



