BULLETIN 39, UNITED STATES NATIONAL MUSEUM. [32] 



it over tlie edge of the boat, it is usually well to look into the mouth of 

 the dredge to see if any very delicate specimens are there. When the 

 dredge is emptied these would naturally be under everything else, and 

 it would be better to take them out, if present, before emptying the 

 dredge. The dredge can be emptied directly into the tub in the boat 

 if it contains material which needs to be carefully examined. If, on the 

 other hand, the contents are chiefly mud, it will be convenient to move 

 it up and down in the water outside of the boat, and thus wash away 

 a iDortion at least of the mud before taking it in. The dredger should 

 take a note of the depth of the water in which the haul was made, which 

 must necessarily be averaged; of the kind of bottom — muddy, sandy, 

 gravelly, or weedy — and of the date. The writer has found it conven- 

 ient to go out supplied with a number of nested wooden tubs, such as 

 are sold for household purposes. The contents of the dredge after 

 each haul can be put into a tub by itself. After all of the tubs are 

 filled, it will be well to examine the contents in order to avoid carrying 

 around useless material. If the dredger is near shore the most con- 

 venient way is to pull to the beach, provided there is no surf. Being 

 provided with a wire sieve, of about a quarter -inch mesh, mud and fine 

 gravel can be screened and the contents lolaced in jars, tin pails, or 

 other receptacles, with the memorandum of the haul, so that no mis- 

 takes shall afterward be made in regard to the locality. 



The proper method of using the sieve is to fill one of the tubs with 

 water, then place some of the mud upon the sieve, which should be 

 about one-half submerged, so that water will enter it to about one-half 

 the height of the rim of the sieve, yet not so deep that the contents of 

 the sieve can be washed over the rim. By using a rotarj^ motion it wil^ 

 soon be found very easy to wash a considerable quantity of mud in a 

 .short time. In washing, the dredger will observe whether there are 

 small shells or other objects so small as to go through the meshes. In 

 case he finds this to be so, after he has washed out a certain quantity 

 of mud, he can pour off gently the muddy water in the tub, and replace 

 it by clean water, and by doing this repeatedly before the mud has 

 time to settle he will find the small shells tolerably clean at the bottom 

 of the tub. If foraminifera or other microscopic objects are desired, 

 it will be necessary to i^reserve some of the mud, either in a wet or dry 

 condition, for examination at home. If the contents of the dredge are 

 not muddy, much less trouble is necessaiy in handling them. The 

 richest bottom is usually gravelly, and this can be washed in the dredge 

 itself before it is taken into the boat. Usually it will pay the dredger 

 to take his tub of gravel home and examine it at leisure, since the 

 necessary care can rarely be given in the midst of the operations of 

 -dredging. If, as sometimes happens, the dredge comes up nearly filled 

 with pieces of kelp, or rolls of seaweed, these should not be hastily 

 thrown overboard, since many animals live in and upon the fronds of 

 weeds, and a careful examination will almost always repay the dredger 



