MOLLUSCA OF THE * CHALLENGES EXPEDITION. \)6 



to retain it for the Australian group of Trochida?, whose brilliant 

 colours distinguish them from the Margaritas. There is a Marga- 

 rita tasmanica of Tenison Wood, from Bass Straits, which, from 

 his description, seems to present some features of resemblance to 

 this species ; but he says of it that the upper part of the whorls 

 is not angulated. Than T. angulatus, A. Ad., this Port Philip 

 species is much larger and higher. It approaches most nearly 

 to T. bellula, Aug. ; but that is larger, with the same number of 

 whorls, has a transparently white apex, has the shoulder below 

 the apex not flat nor drooping outwards, but gouged out as a 

 concave depression, the last whorl is more spread out, and the 

 base is without colour, the umbilicus is wider and less deep, 

 and the spiral which defines it is stronger, while there are no 

 other spirals within it ; the whole surface of the shell, too, is 

 smooth, with a few strong clean-cut impressed spirals, instead of 

 being closely and minutely fretted with spirals all over. 



20. Teochus (Solaeiella) lampeus, n. sp. 



July 29, 1874. Levuka, Fiji. 12 fms. 



Shell. — Depressedly conoidal, angulated at the periphery, 

 rounded on the base, umbilicated, polished, finely sculptured, 

 solid. Sculpture. The glossy surface is closely fretted with fine, 

 curved, oblique, longitudinal scratches, crossed by very similar 

 but slightly stronger and more equal spirals ; these both are 

 stronger near the suture, and feebler on the base, where, indeed, 

 the spirals almost disappear. Colour pellucid pale yellowish 

 white, with many narrow, opaque, pure white spirals, which 

 are flecked with fine zigzag brown longitudinal lines, aggregated in 

 spots, and most abundant near the suture. The strongest opaque 

 spiral is at the periphery, and on it are minute linear interrup- 

 tions of the fundamental colour, and very regularly recurring 

 little brown spots, which are about half the width of their inter- 

 spaces. On the base the brown spots are very few and minute. 

 There is very little iridescence anywhere. Spire low. Apex 

 minute and projecting. Whorls 6, depressed, equally curved, 

 slightly angulated at the periphery, more flattened on the base 

 than above, of regular, but rather rapid increase. Suture slightly 

 depressed. Mouth small, round. Outer lip thin and perfectly 

 simple. Inner lip porcellanous, thick and flat, projecting in a 

 minute ear across the umbilicus, and having toward the point of 

 the pillar a broad backward bevel, cut out of the thickness of 

 the shell round the umbilicus. Umbilicus, a shallow open depres- 



