10 Univcrsifi) of California Puhlicafioiis in Zoology [Vol.15 



tlirown over the rail at either side of the boat's stern, depending upon 

 the direction of drift. At a distance of about fifteen feet the next 

 smaller net (8, 9, 10, or 12) is attached to the rope, and fifteen feet 

 from that one the third net (usually no. 20) is likewise attached. The 

 nets are then allowed to drift away imtil the rope becomes taut, when 

 it is made secure. After a haul of the desired duration has been made, 

 the nets are brought on board, carefully washed with surface water 

 to prevent the organisms from adhering to the netting and being 

 thereby carried over into the next haul, and the contents of the bucket 

 are transferee! into containers such a-s pint, quart, or two-quart "sure- 

 seal" fruit jars, or, if the catch is unusually large, into pails. The 

 catch is then preserved by adding formalin enough to make a ten per 

 cent solution, labelled, and temporarily filed in the naturalist's house 

 in racks specially constructed for that purpose. About five minutes 

 are consumed in hauling-in. wa.shing, transfering, preserving, labelling, 

 and filing the catch, and putting the nets out again. 



(b) The Nanseii closing-nets.'' — To operate one of these nets re- 

 quires the combined labor of an engineer, a man to stand by the bells 

 and read the meter, and two sailors to handle the net itself. When 

 the net is ready to be lowered, the ring from which it is suspended 

 is fastened to the trip which has previously been made secure to the 

 cable and the engineer is signalled to lower. When the net has de- 

 scended far enough, .say 100 meters, the net is immediately raised at 

 a uniform rate of approximately 60 cm. per second until, say, the 

 fifty-meter level is reached. The sailors then send the messenger 

 which, striking the trip, closes the net. A vertical haul has thus been 

 made from one hundred to fifty meters, and the net is hoisted on deck 

 as quickly as possible. It is then thoroughlj- washed with water filtered 

 through netting of finer mesh than that of the net, thereby preventing 

 contamination by surface organisms. After washing, the catch is 

 transfered to containers and eared for as in the case of the surface 

 nets and, while one sailor is transfering the catch, the other removes 

 the messenger and adjusts the net for the next haul. About one 

 minute elapses between the time the net reaches the deck and its 

 descent for the next haul. 



From June 19, 1909, when the Nansen nets were first put into 

 commission, to February 17, 1910, when they were first used for 

 vertical hauling, the only cable with which the " Agassiz" was equipped 

 was too large to carry the messengers and trips. An arrangement 



1 For a liescription of this net see Henlman, Seott, ami Dakiu, 1010, p. 337 



