APPENDIX 521 



cone, and is easily transferred therefrom to a beaker of clean 

 water by everting the cone on the tip of one's finger and 

 washing it off in the beaker. 



If a more expensive net is allowable, a plankton towing 

 net a yard long of silk bolting cloth, that may be drawn from 

 the end of a long pole, will gather the material faster and 

 will be better for use in open water, but not for use in the 

 little openings along the shores. 



2. A few small strainers of different mesh, for sorting 

 organisms according to size. 



3 . Some sort of concentrating apparatus for getting the 

 organisms together so that a number of specimens may be 

 obtained with each drop of water taken up with a pipette. 

 An excellent one may be made as follows : Fold a piece of 

 fine-meshed cloth (bolting cloth, preferably) filter paper- 

 fashion, and place it in a small funnel. Set the funnel in a 

 jar level full of water with a mouth wide enough so that the 

 point of the cloth in the funnel will be immersed half an 

 inch. Set the jar in a larger vessel to catch the overflow, 

 and then pour the water containing the organisms into the 

 funnel until the desired concentration has been reached. A 

 rubber hand bulb on a glass tube will be of assistance in 

 transferring. Some such apparatus will be useful for 

 gathering the material needed for studies 10, n, 15, 16, 20, 

 46 and 49. 



Collecting of the larger organisms will require a dip net of 

 the ordinary shallow sort, so shaped that things can be 

 examined outspread upon it as lifted from the water. Dip 

 nets will be most useful for gathering the material needed in 

 studies 37, 41, 43, 48, 49, 53 to 58, and 62. Here, also, a 

 collecting seine will be more efficient for collecting larger 

 organisms in open water. 



A cyanide bottle for collecting insects is easily made from 

 any wide mouthed bottle by placing some cyanide of 



