On the characters of Astele, a new division in the family of Trochinae, or Trochiform shells; together with the description of another species of the same family

In no department of nature is the adaptation of our systems to the advanced state of knowledge become more imperative than in the elucidation of the Testaceous Molluscae. The number of species discovered since the days of Linnaeus are probably as 1 to 60, and every day fresh novelties are coming to light, requiring new divisions, new names, and new alterations in our system to make these novelties intelligible.