MARGARITA. 299 



the pillar below the periphery ; umbilicus rather narrow, with a 

 deep perforation which exposes the inner whorls. 

 Alt. -1, diam. '15 in. (Jeff.) 



Josephine Bank, 340-430 fms. 



T. cancellatus JEFF., P. Z. S. 1883, p. 96, t. 20, f. 4. 

 Dall has expressed the opinion that this species is a Cyclostrema or 

 Adeorbis. 



M. HRYCHJUS Watson. PI. 64, fig. 50. 



Shell globosely depressed, with a small high spire, very thin, 

 rather opaque, rough, dull, and slightly iridescent. Sculpture : The 

 whole surface looks as if a rough epidermis were gathered into close, 

 minute, obliquely longitudinal puckerings, with stronger folds about 

 0*003 in. broad and 0'005 in. apart. These folds tend on the last 

 whorl to disappear, except near the suture and toward the umbilicus. 

 They are crossed by fourteen to sixteen fine round spiral threads, 

 which at the crossing of each fold rise into knots. On the upper 

 surface of the body-whorl they become very faint ; there are four on 

 the penultimate whorl, the first being remote from the upper suture, 

 the last close to the lower suture. Besides these, the surface is 

 microscopically wrinkled spirally. Color a dead slightly grayish- 

 white, which, toward the mouth, especially when wet, is faintly shot 

 with a green and pink iridescence. Spire rather high, the earlier 

 whorls being small and very much twisted out, so as to rise above 

 one another by almost their entire height. The apex is round and 

 blunt, and terminates abruptly, but all the earlier whorls have lost 

 their outer layer. Whorls 5, very round, of very regular but rather 

 rapid increase. Suture deeply and sharply impressed. Mouth 

 rather oblique round, not descending brilliantly iridescent within. 

 Outer lip thin, turning down to meet the pillar-lip and carried across 

 the short junction with the body by a thin nacreous callus, which is 

 continued within, and is, in fact, the completion of the whorl into a 

 a tube. Inner lip slightly thickened, curved, just barely reflected. 

 Umbilicus wide and pervious, exposing all the whorls, and strongly 

 cross-hatched within by the spiral and longitudinal threads. Oper- 

 culum very thin, clear, and bright, with about eight faintly-defined 

 turns, and marked with microscopic concentric lines. 



Alt. '64 in. diam. '87, lesser, '62 in. Penultimate whorl, 0'8.1 

 Mouth, height 0'43, breadth 0'4 in. (Watson.) 



