A SHOKT HISTORY OF THE INVESTIGATIONS 9 



'Lightning' were the curious Echinoderm, Brisinga 

 coronata, previously discovered by Sars, and the 

 Hexactinellid sponges, Holtenia and Hyalonema, the 

 Crinoids Rhizocrinus and Antedon celticus, and the 

 Pennatulid Baihyptilum Carpenteri, not to mention 

 numerous Foraminifera new to science. 



In the spring of the following year, 1869, the 

 Lords Commissioners of the Admiralty despatched 

 the surveying vessel ' Porcupine ' to carry on the work 

 commenced by the ' Lightning.' 



The first cruise was on the west coast of Ireland, 

 the second cruise to the Bay of Biscay, where dredg- 

 ing was satisfactorily carried on to a depth of 2,435 

 fathoms, and the third in the Channel between Faeroe 

 and Scotland. 



The dredging in 2,435 fathoms was quite successful, 

 and the dredge contained several Mollusca, including 

 new species of Dentalium, Pecten, Dacrydium, &c., 

 numerous Crustacea and a few Annelids and Gephyrea, 

 besides Echinoderma and Protozoa. A satisfactory 

 dredging was also made in 1,207 fathoms. 



The third cruise was also successful and brought 

 many new species to light, including the Porocidaris 

 purpurata, and a remarkable heart urchin, Pourtalesia 

 Jeffrey si. 



