No. 443-] 



ORGANIC REMAINS. 



795 



A good arrangement is to have a porcelain vessel fitted with 

 two sieves, the upper one with meshes of about 2 mm. and the 

 lower 1.5 mm. The sieves are placed about 5 cm. apart, and 

 two currents of water, the velocity of which can be regulated by 

 cocks, should be used, one under each net. Figure 2 shows a 

 contrivance made on these principles and used by the writer 

 with good success. The residue of the slumming need not be 

 examined, if portions of the sample have been reserved for micro- 

 scopic examinations for spores, pollen, alg^e, bryozoa, molluscs, 

 rhizopods, cirripeds and other Crustacea, fragments of echino- 



