(After Keferstein.) a, Pouch for reception of the snout when retracted.
Keferstein.) a, Mouth.
(After Keferstein.) disk or shield.
(From Keferstein.) B, Helicophanta brevipes.
(From Keferstein, after Pfeiffer.) C, Testacella haliotidea.
(From Keferstein.) D, Anion ater, the great black slug.
(From Keferstein.) a, Shell in A, B, C, shell-sac (closed) in D; b, orifice leading into the subpallial chamber (lung).
(After Keferstein.) b, The mouth.
Keferstein, " Untersuchungen fiber niedere Seethiere," Zeitschr.
4 Thus it is to Thompson (1830), and not to Burmeister (1834), as erroneously stated by Keferstein, that the merit of this discovery belongs.
P. Woodward, a model of clear systematic exposition, and the exhaustive treatise on the Malacozoa or Weichthiere by Professor Keferstein of Gottingen, published as part of Bronn's Klassen and Ordnungen des Thier-Reichs.