separate from the marl. We have even added water to the sample in the 

 plastic bag so as to ensure that it would remain wet until it was washed. 



Thorough sampling of a deposit involves collecting from a meas- 

 ured section. In a deposit several feet thick, this means finding a place 

 where the deposit has been cut or sliced through by a drainage ditch, 

 road cut, or excavation and taking out a series of layers of the material, 

 each layer 1 foot by 1 foot by 2 inches thick. It also means labeling the 

 material from each layer and placing it in a separate plastic bag as it comes 

 out of the cut. Likewise, the nature and appearance of each layer should 

 be recorded in a field note book for later reference. Once the sample is 

 collected, it may either be worked up by the collector or turned over to a 

 specialist for sorting, identification, and interpretation. The latter means 

 that the collector misses half the fun and profit from his work, so he is 

 strongly urged to go on to the next two steps which can be easily learned, 

 with some help from a specialist. 



Each sample should be thoroughly soaked in water, overnight or even 

 longer. If the material sticks together and to the shells, the sample should 

 be boiled for a while in water; the movement of the boiling water helps 

 to break up some samples. To separate shells from marl and silts, we have 

 tried all of the following: boiling in water, with and without detergents; 

 agitating in a Ro-Tap machine which shakes the sample through a series 

 of sieves; and exposing the sample to water running through a shower 

 nozzle. Some samples break up as soon as they are soaked in water; others 

 have resisted all treatment and have been sieved, the next step in the 

 process, with various amounts of mud and peat still sticking to the shells. 



The next step is to run the sample through a series of sieves of various 

 mesh sizes so as to get rid of the mud and retain the shells. For this, we 

 prefer large sieves, 8 or 10 inches in diameter, but smaller sieves will do. 

 We have used all sorts of combinations of mesh sizes to ensure retaining 

 the smallest of the land and freshwater snails and ostracodes which are 

 abundant in some lake deposits. 



Next, the samples should be dried by being spread out on several layers 

 of newspapers and left in open air at least overnight. Twelve to 18 hours is 

 enough in heated buildings in winter or on a dry day in summer but a 

 longer time may be required during hot, damp spells in summer. 



Once the samples are dry, they can be boxed, labeled and stored for 

 later study. For this we have used ice cream or cottage cheese cardboard 

 containers of 1 pint and half pint capacity, but any kind of container that 

 will hold such quantities of material will do. The problem is to get enough 

 containers to hold a multitude of samples. If the samples are small, a 

 quarter cup or so, empty flip-top cigarette boxes can be used, but quantities 

 of them must be saved over a period of time to ensure a sufficient supply. 

 Our smoker friends have come to the rescue here and supplied us with 

 literally thousands of empty cigarette boxes over the years; we use them 

 to store both unsorted samples and identified specimens. 



No description of sorting processes need be given here as shell collectors 



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