EditorialMactra concentrica, Print, Mactra is a genus of medium-sized marine bivalve mollusks or clams, commonly known as trough shells or duck clams. Mactra is the type genus within the family Mactridae.
EditorialSerrated tortoise or Kalahari tent tortoise, Psammobates oculiferus (Testudo serrata), and diamondback terrapin, Malaclemys terrapin (concentric tortoise, Testudo concentrica). Handcoloured copperplate engraving by Heath after an illustration by George...