CHAP, vi.] DEEP-SEA DREDGING. 



chief of which was a new crinoid belonging to the 

 genus Bourguetticrinus of D'Orbigny ; it may even 

 be the species named by him J3. liotessieri, which 

 occurs fossil in a recent formation in Guadaloupe, 

 but of which only small pieces of the stem are 

 known. I obtained half-a-dozen specimens between 

 230 and 300 fathoms, unfortunately more or less 

 injured by the dredge. The deepest cast made was 

 in 517 fathoms ; it gave a very handsome Mopsca 

 and some annelids." 



The results of the ' Lightning ' cruise in 1868, in 

 which dredging was successfully carried clown to 

 650 fathoms, have already been recorded. 



In the summer of 1870, Mr. Marshall Hall, F.G.S., 

 with an interest in science which is unfortunately 

 rare among yachtsmen, devoted his yacht ' Norna ' 

 to deep-sea dredging work during a cruise along 

 the coasts of Portugal and Spain. If we may judge 

 by several preliminary sketches which have from 

 time to time appeared at the hands of Mr. Saville 

 Kent, the collections made during this expedition 

 must have been extensive and valuable. 2 



The last researches in order of time are those con 

 ducted on board H.M.S. 'Porcupine' in 1869 and 



1870. With the use of a Government surveying 

 ship well found in all necessary appliances every 

 thing was in our favour, and, as has been already 

 told, dredging was carried down to 2,435 fathoms ; 



1 American Journal of Science, vol. xcvi. p. 413. 



2 Zoological Kesults of the 1870 Dredging Expedition of the Yacht 

 * Norna ' off the coasts of Spain and Portugal, communicated to the 

 Biological Section of the British Association, Edinburgh, August ^, 



1871. Nature, vol. iv. p. 456. 



