MARINE BIOLOGICAL STATION ON PUFFIN ISLAND. 27 



run together with perfect ease by the use of a resistance 

 of about 0*5 of an ohm in the arc-hght circuit. The sub- 

 marine lamps are fitted in strong circular annealed glass 

 protectors, and can be lowered to any required depth in 

 the water by means of a special waterproof flexible cable 

 made of 260 strands of fine copper wire, covered with thick 

 gutta percha and hemp. The arc lamps require from 

 twenty-five to thirty amperes, and the submarine lamps 

 4*5 amperes, so that there is ample power when the whole 

 installation is running. 



This time the two large electric lamps, 3,000 candle-power 

 each, were hoisted up into such a position as to illuminate 

 the deck, and cast a bright light on the water for some 

 distance on each side of the ship. Three submarine incan- 

 descent lamps of 100 candle-power each were then fitted 

 in the mouths of tow-nets, and were let down, two of them 

 to the bottom, at a depth of five fathoms, and the third to 

 a foot or so below the surface of the sea. Each of these 

 nets was put out twice, so that we got four bottom hauls 

 and two surface hauls with the electric light tow-nets. 

 Another tow-net without any lamp was let over the side of 

 the "Hyaena," and lay in the brightly illuminated surface 

 water. AH these nets were stationary, but were kept 

 fairly distended by the tide. At the same time Mr. I. C. 

 Thompson was rowed round and round the ship, dragging 

 an ' ordinary tow-net in the bright area, and this one 

 haul, in addition to many higher Crustacea, yielded Gastro- 

 saccus spinifer, Siriella brooM, and some very interesting 

 varieties oi Atylus swammerdamii, which Mr. A. 0. Walker 

 is now working out, and twenty species of Copepoda, 

 including such rare forms as Pseudocalanus armatus, Ecti- 

 nosoma atlanticum, Zaus spinatus, Laoplionte lamellifera, 

 Dactylopus tenuiremis, B. tisboides, Cijclopina gracilis, 

 Brady a typica, Euterpe gracilis, and quantities of Peltidium 



