On the Echinoidea of the 'Porcupine' Deep-Sea Dredging-Expeditions
Report to the Hydrographer of the Admiralty on the Voyage of the 'Challenger' from the Falkland Islands to Monte Video, and a Position in Lat. 32 degrees 24$^{\prime}$ S., Long. 13 degrees 5$^{\prime}$ W