General Methods of Collecting, 

 Maintaining, and Rearing 



Marine Invertebrates in the Laboratory 



j 



Paul S. Galtsoff, U. S. Bureau of Fisheries 



COLLECTING 



THE selection of the equipment for collecting marine animals is gov- 

 erned by various considerations, of which the character of the bot- 

 tom, depth of water, number of specimens the investigator desires to 

 obtain, the purpose of collecting, and the animal which he seeks, are of 



Gin 



Fig. i. — The dip net. 



paramount importance. The following account describes the instru- 

 ments which may be needed by an individual collector who desires to 

 bring live material to his laboratory. The description of the method of 

 collecting large numbers of specimens for museums and supply houses, as 

 well as the account of the various oceanographic instruments used in a 

 quantitative study of ocean life are beyond the scope of this book. The 

 reader interested in this matter is referred to such books as: Murray 

 and Hjort (1912); Johnstone (1908); Bulletin No. 85, Oceanography, 

 of the National Research Council (1932) ; numerous publications of the 

 Conseil Permanent pour I' Exploration de la Mer ; Wissenschajtliche 

 Meeresuntersuchungen (abt. Helgoland and abt. Kiel), and to the de- 

 scriptions of equipment given in the reports of various oceanographic 

 expeditions. 



The dip net. The dip net (Fig. 1) is the handiest and most indis- 

 pensable piece of equipment that can be used for many purposes and 

 under a great variety of conditions. It consists of a conical net bag at- 

 tached to a stout ring made of galvanized iron or preferably of brass and 



